Vera Rubin: A Life 9780674259386

Citation preview

VERA RUBIN

VERA RUBIN

a life JACQUELINE MIT TON SIMON MIT TON

B E LKNAP PRESS OF HARVARD U NIVE RSIT Y PRESS

Cambridge, Mas­sa­chu­setts & London, ­England 

2021

 Copyright © 2021 by Jacqueline Mitton and Simon Mitton all r ights r eserved Printed in the United States of Amer­i­ca First printing Jacket design: Graciela Galup Jacket art: Courtesy Carnegie Institution for Science, Department of Terrestrial Magnetism Archives. Photograph by A X Photo Studio, Poughkeepsie, NY 9780674259362 (EPUB) 9780674259386 (PDF) The Library of Congress has cataloged the printed edition as follows: Names: Mitton, Jacqueline, author. | Mitton, Simon, 1946– author. Title: Vera Rubin : a life / Jacqueline Mitton and Simon Mitton. Description: Cambridge, Mas­sa­chu­setts : Belknap Press of Harvard   University Press, 2021. | Includes bibliographical references and index. Identifiers: LCCN 2020032833 | ISBN 9780674919198 (cloth) Subjects: LCSH: Rubin, Vera C., 1928–2016. | Astronomers—­   United States—­Biography. | ­Women astronomers—­United States—­   Biography. | Dark ­matter (Astronomy) Classification: LCC QB34.5 .M58 2021 | DDC 520.92 [B]—­dc23 LC rec­ord available at https://­lccn​.­loc​.­gov​/­2020032833

 This book is dedicated to Vera Rubin’s ­family:

her sons, David, Karl, and Allan her ­sister, Ruth her grandchildren and great-­grandchildren

and also to the memory of

Bob Rubin (1926–2008) and

Judy Young (1952–2014)

Contents Foreword

ix

Introduction

1

1 The Lure of the Stars

5

2 An Aspiring Astronomer

27

3 Cornell and the Rotating Universe

46

4 Georgetown, Gamow, and Galaxies

63

5 A Professional Astronomer at Last

86

6 The Call of the Dome

106

7 The Delight of Discovery

129

8 Adventures in Andromeda

152

9 Bright Light on Dark ­Matter

176

1 0 The Dynamic Universe

193

11 Speaking Out for ­Women

208

12 Wonderful Life

232

Appendix: Awards, Honors, and Appointments

253

Notes

257

Acknowl­edgments

297

Index

30 1

Foreword

V

era Rubin achieved many “firsts,” the latest being that she is the first ­woman to have a major observatory named ­after her—­and also “­after” in the other sense of posthumously. Three and a half years ­after she died, the Large Synoptic Survey Telescope project, being built in Chile, has been renamed The Vera C. Rubin Observatory. It is a huge telescope and ­will break new ground, as Vera Rubin did in her lifetime. She had a long and highly productive life, mostly based in Washington, DC, at the Car­ne­gie Institution for Science’s Department of Terrestrial Magnetism, retiring fi­nally at age eighty-­four. For me, she was a trailblazer in two ways: detecting the presence of dark ­matter through the way galaxies rotate; and arguing for the recognition and inclusion of ­women in astronomy. Dark ­matter, although invisible, is as it turns out a major component of the universe. We ­were unaware of its existence ­until we ­were forced by Vera, and then also some radio astronomers, to accept that something invisible was affecting the way galaxies rotate, especially in their outer regions. The implications ­were so dramatic that she had trou­ble, initially, in getting her observational data accepted. The existence of dark m ­ atter was forced upon her (and all of us) by her careful observations of the motion of stars in carefully selected galaxies. Her observational work on the rotation of galaxies has been held in high esteem, and her data is still regarded as outstanding. As well as being a biography, this book gives an authoritative account of the development of astrophysics over the last seventy years, and in par­tic­ u­lar the development of extragalactic astronomy. Th ­ ere is useful historical context, with the authors describing significant (with hindsight) papers that had ­little impact when first published. Thumbnail sketches of other impor­ tant astronomers she met or worked with add texture to the story. My strongest memory of Vera ­will be of her kindness, and her genuine interest in what one was ­doing professionally. My next memory of her is her

x F o r e w o r d

tenacity. She did not have it easy, largely ­because she was a ­woman and a wife and m ­ other. She was forever juggling commitments while clinging (sometimes precariously) to her chosen profession, observational astronomy. And the third memory is what she did to advance the position of ­women in science. She was modest, kindly, determined (when she needed to be), generous and encouraging, astute, thoughtful, and persuasive. All this is brought out wonderfully in this biography. At the start of her ­career, Martin Schwarzschild showed her, in her own words, “humanity and gentleness,” and she would do this herself, especially to other female astronomers. Given that she was of the generation that she was, and that she had four ­children, it is remarkable that she had any c­ areer at all. Her desire to stay intellectually active while rearing ­children resonates. Much credit must go to her husband, Bob. How fortunate that he worked in an area (scientific research) where he had some flexibility and was able (as well as willing) to be supportive in deed as well as in word. He was a pioneer as much as she was. Jocelyn Bell Burnell Oxford, June 2020

INTRODUCTION

O

n January 6, 2020, the 235th Meeting of the American Astronomical Society (AAS) in Honolulu received the official announcement that the Vera C. Rubin Observatory Designation Act had become Public Law number 116–97 in the United States.1 The Act decreed that a major new proj­ect ­under construction in Chile “­shall be known and designated as the ‘Vera C. Rubin Observatory.’ ”2 Never before had a national astronomical observatory been named to honor a ­woman. So why did Vera Rubin merit this notable distinction? In December 1950, a young and inexperienced Vera Rubin had attended her first AAS meeting, in Haverford, Pennsylvania, to pre­sent some controversial conclusions from her master’s thesis. Most of her audience on that occasion w ­ ere highly critical of the work of the unknown twenty-­two-­ year-­old, who had not even started to study for a doctorate. Sixty-­nine years ­later, however, at this 2020 meeting, Rubin is universally acknowledged as one of the most influential female astronomers of her generation, whose life is worthy of commemoration with an unpre­ce­dented accolade. ­A fter her death at the age of eighty-­eight, on December 25, 2016, the Division on ­Dynamical Astronomy (DDA) of the AAS lost no time in naming its recently created Early ­Career Prize to honor Vera Rubin, a remarkable individual who contributed to a transformation in astrophysics and championed the status of ­women in science. The DDA described its decision as “particularly fitting since she was not only an extraordinary scientist, but also well known for her kindness ­towards and encouragement of young scientists.”3 The official redesignation of what was formerly known as the Large Synoptic Survey Telescope (LSST) proj­ect, confirmed into law by the president of the United States on December 20, 2019, was an even more impressive tribute.4 Congress recognized that “Dr. Rubin and her collaborators used their observations, in conjunction with the work by ­earlier astronomers on

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the rotation of stars in spiral galaxies, to provide some of the best evidence for the existence of dark m ­ atter.” Not only that, “Dr. Rubin was an out­ spoken advocate for the equal treatment and repre­sen­ta­tion of ­women in science, and she served as a mentor, supporter, and role model to many ­women astronomers throughout her life.” With t­ hese statements, Congress encapsulated the two intertwining strands that made Vera “a national trea­ sure,” as Matthew Scott, president of the Car­ne­gie Institution for Science (2014–2017), called her soon a­ fter her death.5 Rubin is remembered first and foremost for her pioneering, long-­term studies of spiral galaxies. Her stunning and unexpected discoveries helped to convince astronomers that dark ­matter is a real entity and, further, that it exists in vast quantities. Rubin never claimed that she had “discovered dark ­matter” as a concept, although ­others have mistakenly attributed discovery to her. Cosmologist Fritz Zwicky, writing in 1933, is credited as the first person to suggest ­there could be such a ­thing, ­because known astrophysics could provide no explanation for his observations of how galaxies are moving within their clusters.6 However, few ­people paid attention to Zwicky at the time, and the idea lay more or less fallow for almost forty years. From the mid nineteen-­sixties, Rubin and her colleague Kent Ford de­cided to investigate a dif­fer­ent kind of motion: how the stars and gas clouds belonging to an individual galaxy revolve around the galaxy’s center. They had no intention of searching for dark ­matter but, to her surprise, Rubin found compelling evidence that galaxies are immersed in vast halos of it. In fact, it emerged that some ten times more of this mysterious invisible stuff exists than all the particles of ordinary m ­ atter in stars and gas clouds put together. Rubin was a meticulous observer and pro­cessed her data with the utmost attention to detail, so eventually the truth dawned. Even the most skeptical of critics could not deny the credibility of the observational results she and Ford published, and what ­t hese facts implied, especially in the face of developments in theoretical astrophysics and radio astronomy happening at about the same time. What­ever it is, dark m ­ atter interacts with the ordinary, familiar kind of ­matter via the force of gravity while—at least for the time being—­remaining stubbornly obscure and undetectable by any other means. And yet it is a major component of the cosmos, central to our understanding of the nature, origin, and evolution of the universe. Although Rubin’s research on galaxies branched into other topics, her scientific reputation was principally

I N T ROD U C T I O N 

3

built on her work relating to the debate about dark m ­ atter. Her painstaking studies of the rotation of galaxies made a significant contribution to what had been, up u ­ ntil that time, the most persuasive observational evidence for dark ­matter. An astronomer may justly deserve recognition solely “for significant contributions to the realization that the universe is more complex and mysterious than had been ­imagined,” as the wording of Rubin’s citation for the National Medal of Science put it, but her impact on science, society, and the lives of many individuals was felt far more widely. She forged her early ­career in the face of numerous hurdles, at a time when a ­woman was a rarity in astronomy, or in any branch of science for that m ­ atter. She and her husband, Bob, also a research scientist, raised four ­children while she followed her gradu­ate studies close to home then gradually established herself as a professional astronomer, albeit rather tentatively at first. Hers was an unconventional background but Rubin had the combination of ability, motivation, and character it took to succeed. As she made headway with her own ambition to succeed as an astronomer, Rubin became increasingly exasperated by the multitude of barriers holding ­women back from rewarding scientific ­careers and de­cided to do all in her power to demolish ­these obstacles. She was no longer willing to stand by, watching w ­ omen forced to accept the status quo while working around it as best they could. Rubin was determined to be instrumental in bringing about change. Rubin’s ­daughter Judy, who also became an astronomer, recalled a phrase her ­mother often repeated: “Actions speak louder than words.”7 Rubin lived by t­ hose words, not only speaking out but also proactively lobbying and cajoling, challenging what she saw as sexist language, putting ­women’s names forward as committee members, advisors, reviewers, and meeting organizers, and nominating w ­ omen for honors and awards. All this she did with imagination and good humor, even when she was angered by the need for such special efforts. In her incredibly busy life, Rubin always found the time to do what­ever she could to change ­things where she perceived injustice, or simply to lend encouragement and a helping hand to younger colleagues or students, especially ­women. Her warm personality, generous spirit, and sheer enthusiasm for astronomy won her the gratitude and admiration of the aspiring astronomers who encountered her. Deidre Hunter, a long-­standing colleague, described her as remarkable in her determination, stubbornness, and sense of

4

V ER A R U B I N

fairness, all characteristics that served her well as a tenacious trailblazer who was unrelenting in promoting equality of opportunity and diversity in science.8 Rubin’s leadership in this cause, which was so close to her heart, was memorialized in 2018 when the University of California at Santa Cruz established its Vera Rubin Presidential Chair for Diversity in Astronomy. Many heartfelt tributes have been paid to Rubin by ­people whose lives she touched directly, typically praising her personal qualities as well as her professional prowess. To Alicia Aarnio, for example, she was a “wonderful ­human being and a brilliant scientist.” Rebecca Oppenheimer recalls her as “Such a lovely, modest, encouraging person, while being a fantastic and quite radical researcher.” Julia Nicodemus considers Rubin “ “A hero on so many levels—as a feminist, as a brilliant scholar, as someone who had apparently found work / life balance and a pioneering ­woman in science.” And Scott Trager simply declares her “One of a kind.”9 Vera Rubin earned a prominent place in the history of astrophysics through her findings on dark m ­ atter. As Paul Dabbar, the US Department of Energy’s undersecretary for science, affirmed on the naming of the Vera C. Rubin Observatory, “Dr. Rubin’s life and singular achievements as a scientist remain a model for all ­those seeking to satisfy humanity’s unceasing curiosity about our universe.”10 At the same time, she openly demonstrated that first-­class scientific achievement is compatible with a full and happy ­family life. While tough and obstinate in her fight to make opportunities for w ­ omen in science equal to t­hose open to men, she was a sympathetic and caring friend, colleague, and mentor who gave unstintingly of her time to ­others. Rubin’s curiosity about the universe was what began her own lifelong passion. As an inquisitive eleven-­year-­old, she was seduced by what she found in the night sky and was soon consumed with the idea of devoting herself entirely to astronomy. She became determined to follow her dream however difficult or improbable her journey might appear. Her progression from a childhood fascination with the stars to a stellar ­career makes a compelling story. We begin that story on a cold December night in 1939.

CHAPTER 1

THE LURE OF THE STARS

T

he year was 1939, the place a residential district on the northern side of Washington, DC. The December night air was cool and crisp ­under a clear sky and ­there was a light frost on the ground. On the other side of the Atlantic Ocean, the greatest armed conflict in history was beginning to unfold. Six million Jewish p ­ eople would perish. For now, most Americans ­were oblivious to the Nazis’ expansionist and genocidal ambitions. All was peaceful in the modest row ­house in Tuckerman Street NW, where the Cooper girls w ­ ere growing up in a close-­k nit Jewish f­amily. Vera Cooper and her elder s­ ister, Ruth, shared one of the three bedrooms. Their large bed pushed against the north-­facing win­dow occupied much of the space in the small room. The f­ amily had moved in a few weeks ago and thirteen-­year-­old Ruth had bagged the side of the bed away from the win­dow. Vera, two years younger, was left with the win­dow side. And that was how she became fascinated with the stars.1 Naturally curious and observant, Vera gazed out the win­dow and discovered a captivating celestial show. Although most of the district’s feeble old gas lamps had been replaced by electric ones, their glow was not strong enough to swamp the brighter constellations. On cloudless nights such as this one, as long as ­there was not too much moonlight, the sky was studded with stars. Taking a peek at dif­fer­ent times of night, careful not to disturb her s­ ister, Vera had made what was to her a remarkable discovery: the stars move. As planet Earth rotates daily, the ­whole of the starry heavens seems to wheel overhead. Vera’s win­dow faced ­toward the northern pivotal point of this motion, marked by Polaris, the Pole Star. On one par­tic­u­lar late eve­ning, the third brightest star in the northern sky, brilliant yellow Capella, stood high in her sights. Lower down and farther to the west, the distinctive W-­shape of the constellation Cassiopeia

6

V ER A R U B I N

hung upside down. Round to the east lay Castor and Pollux, the two brightest stars in the constellation Gemini, named for the mythological twins. Apart from Polaris, the faint stars of the ­Little Dipper are always hard to discern, and the Big Dipper had not risen yet. Vera would learn, however, that if she woke again ­later in the night this distinctive pattern of seven stars could be high enough to clear the city skyline. She observed over the next few weeks that the starry view framed by her win­dow at any par­tic­u­lar time gradually changed from night to night. At this hour three months ­later, the Big Dipper dominated her pa­norama of the heavens where Capella had previously shone. ­Later, she would understand why. Each day, our planet Earth makes a ­little pro­gress in its yearly orbit around the Sun, so, each night, she looked out through space at the backdrop of distant stars from a slightly dif­fer­ent a­ ngle. This one eve­ning, though, something unexpected grabbed her attention. For a few seconds, it was as if a bright star streaked through the sky from the east. As she marveled over what she had seen and continued to watch, another blazing trail flashed into view. This was exciting! She recognized them as “shooting stars,” or meteors. They w ­ ere grains of cosmic dust crashing into Earth’s atmosphere at many miles a second. Heated to incandescence, they vaporized in a final few moments of glory. She wondered where they came from: w ­ ere the directions scattered randomly, or w ­ ere they somehow connected? It would be in­ter­est­ing to mark out their tracks on a star map, and she resolved to do so. She would have to memorize what she saw during the night, and then make a drawing of her observations the following morning. She could not possibly turn on the light. It would disturb her ­sister and, in any case, her parents would object to lights g­ oing on late in the night. It ­wasn’t ­because they disapproved of her burgeoning interest in astronomy and her nocturnal activities. On the contrary, they enthusiastically encouraged her scientific ventures. An interest in science and mathe­matics was nothing unusual in the Cooper ­house­hold as Vera’s ­father, Pete Cooper, was an electrical engineer. His early experiences, though, had been hard. Now that he and his wife, Rose, with the help of their extended families, had come through t­ hose difficult times and ­were more secure, their priority was to support their own ­daughters, what­ever their interests and ambitions. Pete was born in 1897 into a Jewish ­family in the province of Vilna in Lithuania, which was ­under the control of the Rus­sian Empire at that time. As a child, his name was Pesach Kobchefski. The fortunes of the Jewish com-

T h e L u r e o f t h e S ta r s 

7

munity in Vilna had waxed and waned over the centuries but, more often than not, Jews ­were viciously repressed and harsh restrictions put on their activities. When Pesach came into the world, anti-­Jewish feelings ­were ­running as high as they ever had. Only 10 ­percent of school places w ­ ere open to Jewish ­children even though 40 ­percent of the population of the city of Vilnius was Jewish.2 As a consequence, Pesach’s early education was ­limited to what he could learn at the Hebrew school, which taught him Hebrew writing and the Torah’s five books of Moses.3 Vera’s grandparents raised young Pesach and his siblings in a modest but not uncomfortable apartment heated by a huge stove. Mr. Kobchefski had transformed the largest room into a workshop where he made leather gloves. At the beginning of the twentieth c­ entury, business was getting difficult as the Rus­sian Empire disintegrated. More and more often, he found he had exchanged his gloves for worthless checks that came back from the bank marked “insufficient funds.” In the end, he could no longer afford the leather to continue making them.4 In 1903, a wave of anti-­Jewish riots broke out in the south of Rus­sia. One of the worst incidents happened in Bessarabia (modern-­day Moldova). Mobs shouting “Kill the Jews” slaughtered forty-­eight victims and injured hundreds more amid scenes of unspeakable horror.5 Worse was to come in the Rus­sian Revolution that began in January 1905, leading to mass protests and strikes. Life became intolerable. Mr. Kobchefski did not want his f­ amily to bear the daily diet of fear, desperation, and humiliation any longer. Th ­ ere was an alternative: emigration. Thousands of Lithuanian Jews had already left. But where should the Kobchefskis go? For a glove-­maker one destination made most sense: Gloversville in the United States. His brother-­in-­law had already taken the radical step of leaving his homeland b­ ehind for this thriving town in upper New York state, where the prospect of refuge, freedom, and a new life awaited. Largely thanks to the skill and industry of Jewish immigrants, Gloversville had rapidly become the center of the American glove-­making industry.6 Officially, the Rus­sian authorities banned emigration. In practice, though, it w ­ asn’t too difficult or dangerous to arrange a passage out of the country. An under­ground network of agents ran a fairly efficient operation, aided and abetted by locals and corrupt border officials. ­These agents liaised with steamship companies and fixed up the long train journeys to the ports in Germany, the Netherlands, and Belgium.7

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In 1905, Vera’s grand­father joined a mass migration when he crossed the Atlantic alone, bound for Gloversville. He promised his wife he would send for her and the ­children as soon as he could earn the money for their passage and find a place for them all to live. It was a ­little over a year before he was ready to receive them. While he had traveled in steerage class, paying the cheapest pos­si­ble fare, he was determined to save his wife and c­ hildren from enduring the same awful conditions. For his ­family, he procured second-­class tickets from an agent in Gloversville, who sold them on credit and allowed his customers to pay him back in installments. So Mrs. Kobchefski closed the door of their apartment in Vilna for the last time and set out with Pesach and her three other c­ hildren on a journey of five thousand miles to join her husband and her ­brother.8 The first stage of Pesach’s journey to his new life was aboard a steam train that chugged slowly across Poland and Germany. At last, the ­family reached the port of Antwerp in Belgium, where they embarked on the SS Kroonland.9 The Kroonland plied the Atlantic between New York and Antwerp for the Red Star Line. She was a relatively new vessel, built in Philadelphia and launched in 1902, and at the time was one of the largest ocean liners ever built in the United States. For the next eight or nine days, the ­family squashed into a small cabin. At mealtimes, they sat at one of the long t­ ables in the second-­class dining room, hung with tapestries and furnished in mahogany.10 On arrival in New York, passengers holding third-­class tickets w ­ ere taken to the famous federal immigration center on Ellis Island, where they ­were put through a grueling inspection. As second-­class ticket holders, the Kobchefskis escaped this ordeal.11 They stayed on the ship overnight, and the next morning, Mrs. Kobchefski’s ­brother arrived to accompany them to Gloversville.12 Eight-­year-­old Pesach’s new home was a second-­floor apartment with the luxuries of gas lights, a bath, and stoves in the kitchen and parlor. School was a ­couple of blocks away. Unable to speak En­glish, he was put in the kinder­ garten at first, but within about three years he had caught up with c­ hildren his own age. Along with thousands of other immigrants fearful of being stigmatized, Vera’s grandparents changed their f­ amily name. Pesach officially became Philip Cooper, though he was always “Pete” to f­amily and friends. In 1915, Pete’s parents moved to Philadelphia to open a leather goods shop. By then, he had just one year to go in high school, so he stayed

T h e L u r e o f t h e S ta r s 

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­behind, lodging with friends. Graduating as one of the top two students of the year, he was awarded two quarter-­eagle gold coins (face value $2.50), which many years l­ater he would pass along as ­family heirlooms to Vera and Ruth.13 The boy who would become Vera Rubin’s f­ather showed a real aptitude for mathe­matics and science at school. ­Later, he would foster in Vera the same enjoyment of working with figures and mathematical puzzles, challenging her and Ruth with number games he in­ven­ted to relieve the tedium of long automobile journeys. He won a scholarship to Union College in New York, but unfortunately it would not cover his living expenses. He opted instead to sign up at the University of Pennsylvania so he could live at home.14 Pete was awarded his degree in electrical engineering in 1920. Tempting as it was to stay on at university, his sense of duty told him he owed it to his ­family to get a job. Major industrial concerns sent man­ag­ers to the school who vied with each other to snap up the new gradu­ates in electrical engineering. The Bell Telephone Com­pany captured Pete with an offer of $1,200 a year to work for them in Philadelphia.15 Around the ­middle of June 1920, Pete reported for duty at the office block where he was to be based. He had barely been ­there a day when he had a chance encounter with a young w ­ oman he recognized, Rose Applebaum. They had recently met at a party and it turned out they ­were working for the same employer. Four years ­later, Rose would become Pete’s wife.16 Rose, too, was a child of Jewish immigrants; her parents had fled to the United States to escape persecution in the Rus­sian Empire. At the age of about sixteen, Rose’s m ­ other (Vera’s maternal grand­mother) had traveled alone from Bessarabia to join friends and ­family in Philadelphia. In her ­later years, this remarkable old lady would enthrall her grandchildren with the story of her journey. Sailing steerage class, she nearly starved b­ ecause she w ­ ouldn’t eat anything ­unless she could be sure it was kosher. She was saved only by the kindness of an officer who brought her fruit. In Philadelphia she met and subsequently married a tailor from the same part of the Rus­sian empire as herself. Rose, the second of four ­children, was born in 1900. Rose attended South Philadelphia High School for Girls and from ­there she went to work in the Bell Telephone Com­pany’s offices. She was employed to calculate the cost of installing telephone lines, taking account of the length of the route. Like the majority of young w ­ omen back then, she expected it to be no more than a way of filling in time before she found a husband.

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Pete and Rose started to see each other regularly but they ­were careful to be discrete, especially at work. Bell Telephone strongly discouraged romantic liaisons between employees working in the same offices. Added to that, Pete’s ­mother urged him not to get too serious u ­ ntil his elder s­ister had made a suitable match, to avoid embarrassment for the f­ amily and any risk of damaging her chances. Such social conventions mattered a ­great deal in Pete’s ­mother’s eyes. So he and Rose kept their blossoming romance quiet—­until July 1923, that is, and the office picnic.17 The picnic was at a farm about ten miles north of Philadelphia. The office buzzed with gossip about who would be ­going with whom. Pete refused to be drawn on the subject. He had a surprise lined up and he intended to do t­ hings in style. To shouts and cheers, he arrived driving the magnificent seven-­seater Studebaker his parents had just purchased. Rose was beside him, resplendent in a large straw hat. The secret was out. The awkward prob­lem of Pete’s s­ ister’s marital status was resolved a­ fter her wedding took place in January 1924. With that obstacle out of the way, Pete and Rose ­were married in March, just a ­couple of months ­later, and Rose resigned from her job.18 While they w ­ ere waiting for the h ­ ouse they had bought at Chestnut Hill in northwest Philadelphia to be altered to their liking, the newlyweds lodged with Rose’s m ­ other. In the summer of 1924, they moved into their h ­ ouse and threw a celebratory party for their friends from Bell Telephone. One of the gifts they received was a chiming clock. Sixty-­five years l­ater, Vera would confess to her ninety-­t wo-­year-­old ­father that, as a young child, she had secretly opened the front of that chiming clock and pushed the hands a ­little ahead of the correct time ­because she was afraid of being late for kindergarten.19 For about five years, Pete and Rose enjoyed a comfortable life in the leafy residential area where they had set up ­house. Friends often paid visits and they started a ­family. Ruth was born in 1926 and Vera in 1928. But then, Pete became dissatisfied and bored with his job. He left Bell Telephone and set up a small laundry supply business with his brother-­in-­law, Philip. He ­couldn’t have chosen a worse moment to start a business. In 1929, the Wall Street stock market crash heralded the start of the catastrophic worldwide economic depression of the 1930s. Practically every­one felt the effects, including Vera’s f­ amily. By 1933, the unemployment rate in the United States had soared to more than 20 ­percent overall and more than 30 ­percent if farm

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11

workers are not included. Many ­people w ­ ere scraping by on part-­time and low-­paid work.20 Pete was struggling to make ends meet. His business began to fail, and what ­little he could earn ­wasn’t enough to keep up the payments on the h ­ ouse. The fateful day arrived when Vera’s impoverished parents had to face the heartbreaking real­ity that they had no option but to leave their home. They found refuge with Rose’s b­ rother, Philip, and his wife for a while. A ­ fter Pete’s ­father passed away in 1934, Pete persuaded a reluctant Rose to move the ­family to his m ­ other’s home. Predictably, the relationship between mother-­ in-­law and daughter-­in-­law was prickly. ­There was ample physical space, but no freedom for Ruth and Vera to behave like normal kids. Rose ­couldn’t help but feel they ­were imposing on her mother-­in-­law. To make ­things worse, the laundry supply business collapsed completely. Rose helped out a bit in the f­ amily leather goods shop and Pete looked for work—­anything to bring in some money. It was the most unhappy time of their married life. Yet somehow they pulled together to protect Ruth and Vera from the real­ity of the nightmare that they and the ­whole country ­were living through. As far as Vera was concerned, ­there was very ­little about her early childhood home life that was in any way remarkable. She grew up, as she put it, “amid a cheery scatter of grandparents, aunts, ­uncles and cousins.” From her perspective, life in the Cooper ­house­hold was pleasantly harmonious—­and musical. Their home was often filled with the sound of her ­mother’s singing; Rose was gifted with an exceptional voice. Pete had given her a baby g­ rand piano as an engagement gift, and both Ruth and Vera went for piano lessons when they w ­ ere old enough.21 They played together but also sometimes squabbled, as siblings do. Their f­ ather, with time on his hands when he was short of work, built them an elaborate doll­house in the style of a colonial mansion, complete with handcrafted furniture, electric lights, and a working radio. It gave the two girls many hours of plea­sure.22 In contrast with her home life, Vera’s first experience of school was not very agreeable. It was even traumatic at times. None of Vera’s l­imited memories of ­those early years at school ­were happy. Discipline was strict and Vera strongly disliked the old-­fashioned schoolrooms with their uncomfortably rigid desks fixed to the floor. As a left-­hander, she had a prob­lem writing neatly enough to satisfy her exacting teachers. A “horrible, horrible” teacher insisted she write with her right hand when she was in the third grade. The same teacher assigned the c­ hildren on one occasion to clip a certain article

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in a Philadelphia newspaper and bring it to the next day’s class. But the Cooper ­family took a dif­fer­ent daily paper and Vera’s parents refused to make a special purchase to satisfy this demand. Vera worried herself sick, so frightened was she of the teacher. By the time Vera was six years old, in 1934, the US economy was starting to improve and job prospects w ­ ere better. Franklin D. Roo­se­velt, the Demo­ cratic governor of New York, swept to power with a landslide victory in the presidential election of November 1932, promising the p ­ eople of the United States a “new deal.” He defeated the Republican incumbent, President Herbert Hoover, with a rec­ord 57 ­percent share of the popu­lar vote, carry­ing forty-­t wo of the forty-­eight states. He went on to be reelected in 1936. On May 6, 1935, Roo­se­velt issued an executive order to establish the Works Pro­ gress Administration (WPA). Its aim was to create jobs for t­ hose eligible to work by undertaking public infrastructure proj­ects large and small. Ultimately, the WPA provided employment for around three-­and-­a-­half million workers. Many jobs w ­ ere created in the public ser­vice and billions of dollars w ­ ere poured into schemes such as building new roads, bridges, schools, and hospitals. Thanks to this initiative, Vera’s ­father found employment. Initially he worked at the Philadelphia Hospital for M ­ ental Diseases, known as the ­Byberry asylum, an institution notorious for its appalling conditions and abuse of m ­ ental patients.23 When the asylum ran out of cash for the wages, Pete found a position as a civilian electrical engineer at the naval shipyard. But ­there, too, the cash flow for his paycheck ran dry and, for want of anything better, he turned his hand to selling insurance.24 When Pete’s friends and f­ amily had taken out as many insurance policies as they could possibly need it became harder to find new clients. Then Pete’s luck turned: while walking down the street one day in spring 1938 he ran into a friend who worked for a civil engineering business. His firm needed someone right away, he said, for a construction contract at the Selinsgrove State Colony for Epileptics in central Pennsylvania. Rose agreed with Pete that he must take the job, even though it was over 150 miles from Philadelphia. They also agreed, however, that it would not be good for Ruth and Vera to start at a new school partway through the school year. So Pete lodged in Selinsgrove during the week, and bought a second­hand Studebaker coupe for $75 so he could drive back to Philadelphia ­every weekend.25

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At that time, coupes and roadsters often had a fold-­down rumble seat fitted inside the trunk, allowing for one adult or two c­ hildren to r­ ide comfortably in the open air. Vera thought a rumble seat would be ­great fun, so she was rather dismayed that her ­father’s car ­didn’t have one. Pete, ever the indulgent parent, transformed the car to match her vision. He rehinged the trunk lid and scoured a junkyard full of wrecks for a seat that would fit inside. Vera absolutely adored the sensation of breezing along out in the cool air: she eagerly noted the miles she and her friends clocked in the improvised rumble seat.26 When the school semester ended, the ­whole ­family moved into a furnished ­house in Selinsgrove that Pete rented from a professor who was spending some time away in Chicago. It was a lovely, memorable summer. Fresh vegetables grew in abundance in the large garden. They had a dog, a cat, and two pet rabbits. On weekends, the place rang with laughter and conversation when friends from Philadelphia descended on them. Rose would often cook a large joint of meat to cater for the ­house party: on Fridays, Ruth and Vera ­were charged with the responsibility of collecting the order Rose had placed with a kosher butcher. Parceled up in dry ice, the meat made a fifty-­ mile journey from the butcher’s shop to Selinsgrove on a public bus. At the bus stop, the Cooper girls paid the driver then trundled the much-­traveled joint to the h ­ ouse in a dolls’ pram.27 Vera grew up with very few books around her outside of school. In the home her ­family shared with her grand­mother from when she was about five years old, ­there ­were no ­children’s books. So it was like discovering unimagined trea­sure when the two girls chanced upon a multi-­volume ­children’s encyclopedia in the attic of the h ­ ouse in Selinsgrove. Almost certainly it was one of the many editions of The Book of Knowledge, first published in E ­ ngland in 1910 ­under the title The ­Children’s Encyclopaedia edited by Arthur Mee. ­These volumes w ­ ere a goldmine of information and entertainment for a child who was full of questions about the world around her and enjoyed making ­things. At the end of the summer, confronted with the dubious prospect of returning to her mother-­in-­law’s h ­ ouse­hold in Philadelphia, Rose dug in her heels. She w ­ ouldn’t go back. Pete knew they could stay in Selinsgrove for a bit longer, but he would soon need a new job. He applied to the rapidly expanding Civil Ser­vice and in the fall was offered a position in Washington, DC.

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The timing was perfect. Pete had had an unwelcome visit at work from a ­union official. Unbeknownst to him, the u ­ nion was in control of hiring workers at the construction com­pany, yet somehow Pete had been brought on without ­going through the usual pro­cess. He was oblivious to the workings of the system, which forced workers to pay kickbacks to the corrupt po­liti­cal machine in Pennsylvania for the privilege of having a job. He was presented with a bill for all he was alleged to owe since he had started working with the firm, and an ultimatum: pay up in ten days or lose his job.28 Pete, fuming a­ fter the u ­ nion steward’s visit, was irritated l­ater that day to see a c­ ouple of tele­grams arrive. He was always taking tele­gram deliveries in connection with his work and was in no mood to deal with them right then. But presently he noticed that one was addressed not to “Chief Engineer” as usual but to Mr. Philip Cooper by name. In fact, both tele­grams ­were offers of employment from Washington. What luck! He had his answer for the ­union man: he would quit before he could be sacked. Pete de­cided to take a job designing the electrical work at a laboratory being built in the Washington suburbs for the Department of Agriculture. In early September, the f­ amily packed what was theirs from the summer home into the old Studebaker with its rumble seat and headed back to Philadelphia to make the big move to Washington. What w ­ ouldn’t fit inside the car was tied to the outside. Pete’s plan was for Rose and the girls to lodge with Rose’s ­mother ­until he found a suitable place for the ­family to live in Washington. In the meantime, Pete’s own temporary lodging would be in a Jewish boarding ­house on ­Fourteenth Street. He begged Rose to stay in Philadelphia ­because privately he was anxious, knowing ­there was another hurdle to overcome before the job was truly his. With his high blood pressure, would he pass the medical examination? What would he do in Washington, he asked himself, with a ­family to look ­after and no job? But Rose was adamant. She was coming to Washington. She arrived t­ here a few days ­after he did and together they trudged the streets looking for accommodation, but what ­little t­here was available to rent was mostly beyond their means. Vera’s f­ather was one of many thousands of Americans flocking to Washington to take up newly created government posts. The district’s population was expanding dramatically, schools w ­ ere bursting at the seams, and 29 the streets w ­ ere full of traffic. About ten ­o’clock one night, as they ­were despondently making their way back to the boarding ­house, they passed an apartment building on Fuller

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Street, near the Polish Embassy, with a vacancy sign outside. “Knock at the man­ag­er’s door,” it said. They did so, apologizing for calling so late and explaining their predicament. They w ­ ere shown an apartment on the first floor. ­There was a living room, a dining room, a kitchen, and a bathroom. Although it had only one bedroom, ­there was an enclosed porch that could serve as a room for the girls. They clinched the deal on the spot.30 Rose returned to Philadelphia to make preparations for the move. A week l­ater, she called to say she would be arriving with the ­children the next day. Pete still tried to put her off for a while, but to no avail. The following eve­ning he returned to the apartment to find it occupied by Rose, Ruth, Vera, and their furniture. Thankfully, Pete passed the medical exam. He and Rose would not leave Washington u ­ ntil they retired and moved to Florida in 1970.31 The Coopers stayed in the l­ittle apartment for a year. Vera, enrolled in the fifth grade at H. D. Cooke Elementary School, in the Adams Morgan school district, could scarcely believe the contrast in teaching style between the strict establishment she had left ­behind in Philadelphia and her new school. For a start, the t­ables and chairs w ­ eren’t bolted to the floor. The ­children could arrange them to suit dif­fer­ent activities. School could be enjoyable, Vera discovered, and she loved it t­here—­especially cutting and pasting and making ­things. One difference, however, was quite shocking for the young Cooper girls. Unlike Philadelphians—­living in the cradle of In­ de­pen­dence and the American Enlightenment—­Washingtonians believed in racial segregation. In Philadelphia the girls had classmates of all colors, but ­here, for the first time, they encountered separate schools and distinct seating on public transport.32 For all the adjustment required for life in Washington, Pete liked his new job. Three million dollars’ worth of electrical work had been commissioned for the laboratory, and Pete was rapidly promoted to head up the electrical team. At last he and Rose ­were feeling more prosperous and secure. In 1939, the ­family moved to the ­house in Tuckerman Street, where Ruth and Vera had a proper bedroom to sleep in and another room to use as a den. And when Pete could no longer patch up the old jalopy, he replaced it with a Pierce-­A rrow six-­seater sedan, a luxurious car much favored by Hollywood stars and tycoons. Pete had located one that was six years old and had enormous mileage on the odometer, but remained in good condition. The naval officer who owned it had priced it for quick sale, and Pete was delighted to oblige.33

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The sense of well-­being the Cooper f­ amily enjoyed was, alas, short-­lived. By early 1941, a somber realization had overtaken the country that the United States would inevitably be drawn into the war in Eu­rope. Preparations for war took pre­ce­dence over agricultural labs, and so the building work came to a halt. The US Army Signal Corps asked for Pete to be transferred to them ­because of his experience working at Bell Telephone, and he was duly moved. On December 7, 1941, the Japa­nese attack on Pearl Harbor caused the United States to declare war on Japan, Germany, and Italy. Pete remained with the Signal Corps ­until the war ended in 1945.34 The same years saw Vera move up from elementary school to Paul Ju­nior High School—by which point she had discovered the stars. They ­were utterly compelling for her, calling her. As she l­ater recalled, t­ here was “nothing so in­ter­est­ing in life as watching the stars e­ very night.”35 The idea that she could be an astronomer—­able to study them for the rest of her life—­began to take shape in her mind. She had to find out as much about stars as she could. Once hooked on the subject, Vera turned to the astronomy books in the public library to satisfy her curiosity. Naively she i­magined that if she read enough books she would “understand it all.”36 The books designed simply to map the night sky and help readers identify constellations w ­ ere of very ­little interest to Vera b­ ecause they told her nothing about the stars themselves. The visual experience of watching the real night sky was dif­fer­ent, though. Two remarkable phenomena that took place in 1940 to 1941, when she was twelve to thirteen years old, made a long-­ lasting impression on Vera.37 The first was an exceptional alignment of Jupiter and Saturn, both brilliant to the naked eye. The two planets closed in on each other, then parted again on three separate occasions between August 1940 and February 1941, like partners in a slow, stately dance. Such a series of close encounters between Jupiter and Saturn takes place, on average, only once e­ very 120 years, ­because Earth, Jupiter, and Saturn must be lined up on the same side of the Sun in a par­tic­u­lar way. At the time, Vera was not aware that she was watching a rare event, but in fact it had not happened since 1683 (the year 1821 having been a near miss). On August 8 and October 11, 1940, and on February 16, 1941, the two planets w ­ ere about twice the Moon’s dia­meter apart. Vera would have the chance to see another such sequence, in 1980 to 1981; the next w ­ ill not occur u ­ ntil the year 2223.38,39

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The second event that stuck in Vera’s memory occurred on the night of September 18–19, 1941, when Earth’s magnetic field was massively disrupted during one of the most intense geomagnetic storms known to have battered the planet. An exceptional group of sunspots had developed, large enough to be vis­i­ble to the naked eye. The Sun’s rotation had brought them to the center of the Sun’s face as seen from Earth when the region flared up and directed a blast of electrically charged particles ­toward Earth. When the cloud arrived some twenty hours ­later, the colossal disturbance to Earth’s normally rather steady magnetic field had dramatic consequences. Brilliant auroras lit up the sky as far south as Florida. It was a clear moonless night and Washington was treated to a fantastic display of rays and rippling curtains in hues of pink, green and lavender. Pete and Rose took their ­daughters to view the spectacle from Hains Point in the East Potomac Park, overlooking the confluence of the Potomac and Anacostia rivers in southwest Washington. Transformers groaned and vibrated as electrical power grids experienced uncontrollable surges. Radio interference and blackouts w ­ ere reported around the world. Amer­i­ca was not yet at war but, in Eu­rope and at sea, the warring sides took advantage of a night sky lit up as bright as day. As the cover of darkness was torn away, the Nazis torpedoed an Allied convoy in the north Atlantic and bombed Leningrad. Meanwhile, the British lost no time in bombing a German supply base in the Baltic Sea.40 Seeing ­these celestial won­ders fueled Vera’s desire to be an astronomer, but it was the stars and the galaxies to which they belong that would become her preoccupation. Astronomers had realized the vast scale and extent of the universe beyond our own galaxy by the 1930s. The Milky Way, they had found, is a disk of stars rotating, not around the Sun, but around a distant central hub in the direction of the constellation Sagittarius. Spiral nebulae, such as the ­Great Nebula in Andromeda, are not glowing gas clouds within the Milky Way as once thought, but separate galaxies at unimaginable distances beyond the Milky Way. Even harder to grasp was the concept that our universe is expanding. Clusters of galaxies are rushing apart as the fabric of space and time itself expands. The theoretical framework of Albert Einstein’s new theory of gravity (1915) fitted convincingly with groundbreaking observations by astronomers such as Vesto Slipher, Milton Humason, and Edwin Hubble to establish that the universe is expanding. The study of the universe as a w ­ hole on a g­ rand scale, which we now call cosmology, was

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developing as a novel and mind-­bending branch of astronomy. And it all needed explaining in everyday language to the public at large: to ­people like Vera. The British physicist Sir James Jeans was one of the writers most successful at satisfying the demand for plain-­language descriptions of the latest developments in astronomy. A ­ fter a brilliant academic c­ areer, spent mostly at the University of Cambridge, he retired in 1929 at fifty-­one, and turned to writing popu­lar books. Vera borrowed them from the library—­books with titles such as The Universe Around Us, Through Space and Time and Stars in their Courses. She would have read Jeans explaining, “As soon as we know the speeds with which the stars move round the hub [of a galaxy], we can weigh the system of stars, just as we could weigh the sun when we knew how the planets moved around it.” 41 She could not have i­magined that some thirty years ­later she herself would be weighing galaxies in this manner, and with startling results. Sir Arthur Eddington was another ­great British astrophysicist and mathematician with a talent for popu­lar writing. He was on Vera’s reading list, too. In his short 1933 book The Expanding Universe, he tackled concepts difficult to visualize, such as the curvature of space. Challenging ideas like this ­were the ones that ­really intrigued Vera.42,43 Almost certainly Vera would also have been impressed by Edwin ­Hubble’s 1936 book, The Realm of the Nebulae.44 It was based on a series of public lectures he gave at Yale University in 1935 and in it he summarized three pieces of landmark research he had himself published between 1925 and 1929. Hubble showed beyond doubt that the newly mea­sured distances of two prominent spiral nebulae placed them far outside the bounds of the Milky Way, devised a system to categorize galaxies according to their shape, and established that the speeds of receding galaxies are in direct proportion to their distance. To achieve ­these breakthroughs, Hubble had used the largest telescope in the world at the time, the 100-­inch reflector at Mount Wilson Observatory in California. Apart from reading, ­there ­were other activities that fed Vera’s ambition to “understand it all.” When she was about fourteen or fifteen, she wanted to go to the monthly meetings of an amateur astronomers’ club in Washington. Concerned about his adolescent d ­ aughter traveling alone in the eve­ ning, but not wanting to discourage her, Vera’s ­father accompanied her to ­these gatherings. They ­were memorable eve­nings out for Vera: she came face

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to face with famous astronomers for the first time. Harlow Shapley and Donald Menzel are two names she ­later recalled, ­people she would come to regard as colleagues. Shapley, a distinguished figure in his late fifties when Vera attended his talk, was director of the Harvard College Observatory. In 1919, he had correctly deduced that the Milky Way is much larger than had previously been supposed, and that its center is thousands of light years from the Sun, based on his painstaking observational program to map out in space the locations of the numerous globular star clusters in our Galaxy. The younger Menzel, also from Harvard, was at the time Vera heard him speak using his skills in mathe­matics and physics as a Navy lieutenant commander, working in intelligence during the Second World War. He went on to succeed Shapley as Director at Harvard College Observatory in 1952. Among professionals, Menzel was known for his studies of the Sun and gaseous nebulae, as well as being an engaging communicator and popu­lar writer. At the age of about fifteen, Vera de­cided to make her own telescope. L ­ ater, in hindsight, she mused that it was “­really a total flop, but was sort of fun.” 45 The improvised tube came ­free from a shop that sold rolls of linoleum floor covering. Vera fetched it from downtown by public transport. No one who saw her on the bus that day could possibly have guessed why a young girl would be lugging this cumbersome cardboard tube. A modest objective lens some two or three inches across came from a scientific supplier. Unsurprisingly, when mounted on the flimsy wooden tripod that Vera and her ­father had managed to concoct, the homemade telescope w ­ asn’t very stable, and it certainly w ­ asn’t equipped with a motor for tracking the rotation of the sky. Vera was disappointed with her first attempts at photographing the Moon. The prints w ­ ere hopelessly blurred. She was rewarded with more pleasing results, however, when she abandoned the telescope and simply left her camera facing north with its shutter open for a c­ ouple of hours! The movement of the stars around the sky that had so captivated her attention several years ­earlier, she could now capture permanently on film. She was very proud of ­these efforts. She carefully taped onto black ­album pages her blurred, overexposed images of the Moon, alongside pictures of arcing star trails and of the homemade telescope. ­These mementos of her first attempts at astronomical photography would remain with her throughout her life. Vera, with her ­sister and parents, frequently traveled to Philadelphia to visit the grandparents, aunts, u ­ ncles, and cousins they had left b­ ehind. The four-­hour drives could be tedious, but t­ here ­were always Pete’s number games

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Fig. 1.1 Vera Rubin aged fourteen years with her homemade telescope. (DTM, Car­n e­gie Institution of Washington)

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Fig. 1.2 Star trails around the north celestial pole photographed by Vera Rubin in October 1943, when she was fifteen years old. (Rubin ­f amily)

to c­ ounter the boredom. Vera once spent the trip working out for herself the solution to the mathematical puzzle of how many dif­fer­ent vehicle license plates can be made with three numbers and two letters. Despite the long journeys, she looked forward to her visits to Philadelphia, not only ­because she would see her ­family but b­ ecause it was the home of the Franklin Institute. As a ten-­year-­old she had fallen in love with the Institute’s science museum and she often went back ­there with a cousin. The museum had opened

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in 1934, billed as a “Wonderland of Science,” and it featured pioneering interactive exhibits.46 Two of ­these particularly fascinated Vera. One was an arrangement of inverted hollow cones, suspended from the ceiling by chains. The cones ­were filled with sand, which drizzled out of a hole at the cone’s tip. When the cones ­were set swinging like pendulums, they gradually made smaller and smaller oscillations, and the sand trickling from them created intricate curved patterns on the floor beneath. Vera said she “could have spent a day in front of ­those,” but she also wanted to make time for the amazing arrangement of mirrors and lights set up as a walk-in kaleidoscope. At home, Vera commandeered her m ­ other’s cake-­icing equipment—­a con­ve­nient aluminum tube with a screw-on piece at one end—to make her own kaleidoscope. The new museum incorporated something of special interest to the wouldbe astronomer: the Fels Planetarium. It was only the second public planetarium installed in the United States, ­after the Adler Planetarium in Chicago. Sitting inside the darkened dome for a conducted tour of the sky must have been totally magical for a girl already seduced by the stars. Instead of having to keep awake all night to see the parade of constellations, she could see their wheeling sweep through the sky play out overhead in a ­matter of minutes. The auditorium had five hundred seats arranged in concentric circles around the Zeiss projector at its center. Even the entrance lobby, with its walls lavishly clad in travertine, was im­mensely impressive. Photo­graphs from Yerkes and Mount Wilson observatories ­were on display and a real-­ time image of the Sun was projected onto a screen from an instrument on the roof above. Just before entering the main door to the auditorium Vera would have passed a large orrery inside a glass globe five feet across. It was a working model featuring all the planets out to Neptune accompanied by their known moons. Still more astronomical exhibits and a public observatory equipped with a twenty-­four-­inch reflecting telescope occupied an upper floor.47 It’s no won­der Vera was a frequent visitor to the planetarium. On one occasion, before g­ oing into the show, she purchased a picture postcard of the Moon. She addressed the card to her ­sister and added a few lines to say she was sitting in the planetarium waiting for the show to start and listening to Gersh­win’s “Rhapsody in Blue.” In 1986, Vera returned to the Fels Planetarium as a celebrity to give a talk. The postcard, preserved in the collection she and her ­sister had made, served as a perfect introduction to her illustrated lecture.

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Fig. 1.3 Vera Rubin (left) and her older ­sister, Ruth, as teen­agers, c. 1945. (DTM, Car­n e­gie Institution of Washington)

While Vera remembered the way the Franklin Institute presented science as engaging and exciting, she could never say the same about her high school experience of science. Socially, Vera got on well at high school: it was “fun” and she found the classes “easy.” 48 She had friends, went on dates with boys, and enjoyed editing the school yearbook. At the same time, she felt she was dif­fer­ent from most of her fellow students, having less interest in the usual teenage preoccupations. Staying at home and reading was often a more attractive proposition than ­going out to a dance or a movie. The school was a short walk from where she lived. Its classical frontage, a ­grand pediment spanning a row of imposing columns all crowned with a cupola, still f­aces up Tuckerman Street NW from its site on the opposite side of Fifth Street. It had not long been open, having been built b­ ecause a rapid increase in Washington’s population had led to overcrowding at the nearby Roo­se­velt High School.49 The local citizens ­were not impressed with the initial plans the Board of Education put forward in 1937. They protested that the proposed two-­story brick building with a flat roof would look more

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like a factory than place of learning. They ­were united in wanting the school that graced their neighborhood to match the architectural grandeur of ­Roo­se­velt High’s columned portico and tower.50 The Board of Education capitulated and the design was changed.51 Even so, the local p ­ eople ­were 52 divided on what the school should be called. The name Calvin Coo­lidge High carried the day over the uninspired temporary name of Northern High. Coo­lidge, the thirtieth US president had held office between 1923 and 1929, and was one of only a few former presidents who had no school in the district named in his honor. The new school bearing his name opened its doors to the first students in 1940. Although Vera was passionate about science, her relationship with her physics teacher at Coo­lidge High was l­ittle short of disastrous. It may have been partly her own fault, she l­ater acknowledged. Although she and Ruth ­were close, Vera felt she was in the shadow of her older s­ ister, who had done well at school and got on with the teachers. The in­de­pen­dence and determination that w ­ ere so much part of Vera’s personality w ­ ere already evident, and she expressed her individuality by deliberately behaving differently. She rebelled against comparisons and any expectations the teachers had of her. Importantly, for the first time in her life, Vera also encountered sex discrimination and the real­ity of being female in a traditionally male-­dominated culture. Vera remembered the physics class as being “a big macho boys’ club” and the physics labs as “a nightmare.” As a girl, she felt like a misfit and an outsider. The main responsibility for that state of affairs she laid firmly at the door of the man who taught them. He did not seem to know how to include the few girls in the class, so he chose to ignore them.53 Her sense of alienation began on her very first day. ­There was a discussion about what scientific investigation is and what it means to be a scientist—­something that would have been close to Vera’s heart even back then. But the way the teacher illustrated one of his themes rankled with Vera, and she ­wouldn’t forget it. Some discoveries, the teacher said, took insight and brilliance. He quoted examples, all featuring men. Other scientists who made impor­tant discoveries, he asserted, relied more on diligence and hard work than brilliance. His one example was Marie Curie. Vera’s reading of this was that he considered men superior to ­women when it came to science—­even to a ­woman who had won two Nobel prizes. Vera often felt angry with this teacher ­because of his attitude, and she rarely spoke.54 He never knew of her interest in astronomy. Rather, it was

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her En­glish teacher who knew that astronomy inspired Vera. Whenever Vera needed to produce a piece of creative writing, she drew on her passion for astronomy. An En­glish term paper in her final year, for example, began with this setting of the context: “Near the center of one of the innumerable galaxies of the heavens is a small star. Viewed from the outside of the galaxy and judged by its con­spic­u­ous brightness and size, it is not unusual.”55 It ­wasn’t only in physics that Vera encountered discrimination. Th ­ ere seemed to be an assumption that the classes in mechanical drawing would be attended only by boys, so Vera ­wasn’t sure girls w ­ ere allowed sign up for them. Nevertheless, she wanted to learn. And why ­shouldn’t she? At home, Vera enjoyed making t­ hings. When she was fourteen, she spent hours during her Christmas vacation making a model of a Ferris wheel with toothpicks and airplane glue, and followed up with a prizewinning account of what she had done for the young readers’ section in the local newspaper.56 The mechanical drawing classes w ­ ere taught in what Vera described as “the boys’ wing of the school” where the workshop facilities for technical subjects and the boys’ gym w ­ ere located. We d ­ on’t know ­whether she had to take any special action to be admitted to the classes, only that she talked a girlfriend into joining her and the two of them went together. It was clear that Vera was maturing into the kind of young ­woman who would neither let being female ste­reo­t ype her nor be daunted by any obstacles that stood between her and achieving her ambitions. If physics classes ­were a nightmare, mathe­matics went like a dream. Even at the end of her ­career, Vera ranked Mr. Lee D. Gilbert as the best math teacher she had ever come across. He excelled at communicating his enthusiasm for mathe­matics and, above all, he had a remarkable knack for getting his students to think logically and explain ideas. “Talk as if the ­people listening to you are blind and draw as if they are deaf” was his mantra when he called students to the blackboard. He liked to amuse them with curious ­little mnemonics, which appealed to Vera’s fascination with numbers for their own sake. To remember that the square root of 3 is 1.7321, for example, he told students to think of George Washington, born in 1732—­and ­because ­there was only one of him, to put a 1 on the end. Vera never forgot that. At one stage, Pete tried to talk his d ­ aughter into being a mathematician, fearing she could never make a ­career out of something as specialized as astronomy. But, much as she loved mathe­matics, for Vera it could never be an end in

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itself or have any practical purpose more valuable than as a tool to solve astronomical prob­lems. For most of Vera’s last four years at school, Amer­i­ca was at war. Nearly all the young men graduating from high school went straight into the ser­ vice. Vera found a weekend and holiday job in the office of the Selective Ser­ vice System. This agency, headed by Major General Lewis B. Hershey, was responsible for managing the draft, which Roo­se­velt had instituted in 1940. Vera’s job was filing. With almost fifty million men between the ages of eigh­ teen and sixty-­four registered as eligible for conscription in accordance with the law, t­ here was a g­ reat deal of filing to be done, and teen­agers as young as fifteen ­were recruited to do it. Vera appreciated the few dollars a day she earned in pocket money but detested the mindless work. The tedium was almost unbearable. Her m ­ other tried to cast it as a good experience to see what it was like for someone to have to do a job they d ­ idn’t like. That argument fell on deaf ears. In the summer of 1945, a­ fter Vera had graduated from Coo­lidge High, she sometimes took the bus downtown with her f­ ather. One par­tic­u­lar day always stood out for her ­later as her most dramatic memory of that war­time period. It was August 7 and the news was flooded with just one story. The United States had dropped an atomic bomb on Hiroshima the previous day. On August 15, Japan surrendered. World War II was fi­nally at an end throughout the world. Vera was seventeen years old, preparing to go to college and live away from home for the first time.

CHAPTER 2

AN ASPIRING ASTRONOMER

O

ne day during Vera’s se­nior year at Coo­lidge High, Rose appeared clutching an impor­tant letter that had just arrived. Inside the sealed envelope was news of a decision they had been anxiously awaiting ­because it would determine Vera’s f­ uture. It was good news: Vera had been awarded a scholarship to study at Vassar College, a ­women’s liberal arts college in Poughkeepsie, a small city on the Hudson River, seventy-­five miles north of New York City. Despite her low opinion of her physics teacher, Vera could not resist the satisfaction of telling him about her success. His parting words to her ­were tepid encouragement: “You should do okay as long as you stay away from science.”1 It was the last exchange they ever had. Fortunately for science, Vera had not the slightest intention of heeding his misguided advice. Securing the scholarship was vitally impor­tant. As she thought about what to study and where, Vera was adamant that she wanted to attend a college that taught astronomy at the undergraduate level. It had to be astronomy, not physics. Her high school physics teacher had succeeded in making that very word anathema to Vera. Any mention of physics instantly reactivated the power­f ul negative emotions that had overwhelmed her in his lessons. Since t­ here was nowhere in Washington offering astronomy, all options for the ­future astronomer would mean living away from home. Both board and tuition would have to be provided since the Cooper ­family did not have the money to pay for Vera’s college education. Swarthmore College and the University of Pennsylvania had made it onto Vera’s short list as well as Vassar. Swarthmore, a coeducational liberal arts college in Pennsylvania, had a well-­established department of astronomy led by Peter van de Kamp. Vera had not thought to contact the astronomy department directly and simply filed an ordinary application. Her interview at Swarthmore started on the wrong foot, then went from bad to worse. Vera

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Fig. 2.1 Photo­graph sent by Vera Rubin with her application to Vassar College in 1945. (DTM, Car­n e­g ie Institution of Washington)

was not surprised to be rejected. The female interviewer did not take Vera’s scientific interest in astronomy seriously. When Vera mentioned painting as one of her hobbies, her interviewer seized upon it and asked w ­ hether she had considered a ­career painting astronomical scenes. The suggestion was so laughable it became a ­family joke recounted even many years l­ater. Vera was accepted both by her ­father’s alma mater in Philadelphia, the University of Pennsylvania, and by Vassar College. A ­couple who ­were close friends of the ­family—­Goldie Back, who had been Rose’s schoolmate, and her mathematician husband Michael Goldberg—­had recently been to a meeting of the American Mathematical Society at Vassar. The ­couple interacted a fair amount with the Coopers and their d ­ aughters. Vera admired them and their academic way of life. It impressed her that the Goldbergs had been to Vassar, if only for a meeting. And Vera also knew that, when Vassar College was founded in 1865, its first professor of astronomy had been a ­woman—­Maria Mitchell. Maria Mitchell (1818–1889) was the first American ­woman to make astronomy her profession, and also a pioneer of ­women’s education. Born and brought up on the small island of Nantucket, once the whaling capital of the world, she became a competent mathematician and a skilled observer ­under the tutelage of her ­father, William Mitchell, although she had no formal post-­secondary education. In 1848, while scanning the sky with her small telescope, Maria discovered a comet. No other American had success-

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fully claimed priority as the first person to spot a previously unknown comet through a telescope. Some years e­ arlier, the King of Denmark had instituted an award of gold medals for such discoveries, subject to certain rules being followed for informing the relevant authorities. The President of Harvard College, Edward Everett, was a friend of William Mitchell and he was keen for one of the Danish medals to come to the United States, believing it would raise the international status of American astronomy. He believed that, if he played his cards correctly, a medal might be secured for Maria, even though the rules had not been followed strictly. His campaign to promote Maria’s claim succeeded. She received the royal medal and was suddenly catapulted to celebrity status as one of the most famous ­women in the United States. Shortly afterwards, Mitchell was appointed to her first paid appointment d ­ oing astronomical work: each year calculating t­ ables of the predicted position of Venus for the newly established American Nautical Almanac, which was published annually.2 When the brewing magnate Matthew Vassar de­cided to spend a substantial part of his fortune on establishing a college for w ­ omen, he set out to recruit Maria Mitchell to the academic staff as its professor of astronomy. Vassar held her in high regard, giving her the accolade of “foremost w ­ oman of our land.” Some of the trustees ­were strongly opposed to appointing ­women to the faculty even though the college’s aim was to provide a “thorough, liberal education” to young ­women. They ­were ultimately overruled, however, and Maria was appointed in 1865, a few months before the college welcomed its first students. The offer came as a surprise to Mitchell, who had never i­ magined herself in such a position, but Vassar’s efforts to provide her with the best pos­si­ble facilities for her astronomical work won her over. The observatory was a large and impressive building housing a twelve-­inch refracting telescope and vari­ous other instruments, and would also serve as a residence for Mitchell and her aging widowed ­father.3,4 Maria’s teaching methods ­were a mixture of practical work and thorough grounding in mathematical methods. She believed in setting high standards and involving her students in discussion and meaningful scientific activity rather than lecturing to them.5 ­A fter Maria’s retirement in 1888, a succession of ­women observatory directors carried on the traditions she had established. One of her star pupils, Mary Watson Whitney (1847–1921), succeeded her and built on her former professor’s teaching style. Whitney in turn was followed in 1915 by one of

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her own students, Caroline Furness. When Furness died in 1936, the post went to Maud Makemson (1891–1977). She was director of the observatory and had been made a full professor when Vera entered Vassar College in 1945. Makemson was to be Vera’s principal teacher and a formative influence on her. Makemson had graduated from the University of California in 1925 at the age of thirty-­three, having been attracted to astronomy ­after an ­earlier ­career as a journalist. Berkeley awarded her a doctorate in 1930, and in 1932 she joined Furness at Vassar as assistant professor. She was a strong candidate to take over the observatory directorship. Henry Norris Russell, professor of astronomy at Prince­ton, advised the fifth president of Vassar, Henry Noble MacCracken, that Makemson was a safe appointment. He added that she was more likely to stay at Vassar than male contenders for the position ­because, as a w ­ oman, she would not receive more tempting offers from 6 elsewhere. Makemson’s expertise lay in two totally dif­fer­ent areas of astronomy. At first, she had concentrated on the mathematical theory ­behind calculating orbits. Her doctoral thesis concerned the orbit of Comet Gale, discovered in 1927, and she published a number of notes on the orbits of minor planets, including 1312 Vassar, which was discovered in 1933.7 She had suggested the name herself to honor the college ­after computing its orbit.8 Subsequently, Makemson’s main interest changed. She became fascinated by “archeoastronomy,” curious to understand how, in the past, ­people of dif­fer­ent cultures had tried to understand astronomical phenomena. In 1935, supported by Vassar College, she went to Hawaii to study Polynesian astronomy, and in 1941–1942 she was awarded a Guggenheim Fellowship to study Mayan astronomy. When Vera applied to Vassar in 1945, it was less than sixty years since Maria Mitchell herself had been teaching t­ here, and no other college could match the unbroken tradition of ­women holding the highest faculty positions in astronomy. It was a place where the concept of ­women astronomers was normal and had been from the beginning; Vera could be sure she would be able to study astronomy throughout her time at Vassar. Further, the college guarded its reputation as a place where students could follow a flexible curriculum and w ­ ere encouraged to think in­de­pen­dently. In January 1946, Vassar’s president told alumnae assembled for an annual luncheon in New York, “­There must be consent of the student to her own education.” Courses

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of study must not be prescribed but must be chosen by the student. “If a ­woman is old enough to decide whom to marry she is old enough to decide what to study.”9 Vassar’s approach to learning, pioneered in the early days by Mitchell and other founding faculty members, had not changed.10 That ethos promised Vera an environment where she could flourish. In the end, it was the practicalities of the scholarship offer that clinched the m ­ atter of which college she would attend. In 1891, the Vassar Students Aid Society had set up a Washington branch to raise scholarship funds for local students. By the 1940s, the scholarship program had been incorporated into the activities of the Vassar Club of Washington, DC, and it was thanks to the efforts of local Vassar alumnae that Vera could pursue her ambition.11 Vera traveled to the Madeira School, a top-­flight private high school for girls in McLean, ­Virginia, about eight miles northwest of DC to be grilled by its headmistress and founder, the formidable Lucy Madeira Wing (1873–1960). Miss Madeira was a Vassar alumna (1896) and charged with interviewing the scholarship candidates on behalf of the club. On the day of the interview, in mid-­February 1945, Vera left Coo­lidge High School early. It was raining and, as she crossed the street, she looked up. She saw a pro­cession of half-­a-­dozen cars coming down the road. It must be someone impor­tant, she thought, and to satisfy her curiosity she de­cided to wait. She stood in the rain getting wetter and wetter ­until, as the cars passed, she recognized the president, Franklin D. Roo­se­velt, sitting beside one of the ­drivers. When he glanced out at the bedraggled Vera, he laughed. Roo­se­velt, it turned out, was on his way back to the White House from the Yalta Conference, where he had met with Joseph Stalin and Winston Churchill to discuss the f­ uture of Eu­rope as the war entered its final stages.12 Vera must have made herself presentable enough before the interview ­because Miss Madeira was sufficiently impressed to recommend her for an alumnae scholarship. The award to Vera paid a ­little over half the annual cost of $1,250 for board and tuition. The college itself topped up that award with a further one of around $200. It was enough to enable Vera to accept the offer of a place. When Vera arrived at Vassar in September 1945, every­thing was still on a war­time footing. It was only about a month ­after V-­J Day and it would take time for a new peacetime order to diffuse through the college. The student newspaper, the Vassar Chronicle, recognized that victory did not signal a return to the prewar social order but would herald a period of change.

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Capturing the mood on the campus, it declared, “The war is over. We’ve won our chance to build a new world. Cars, cigarettes and maids may return to Vassar, but we cannot return to pre-­war attitudes and ideas. We’ve got to work for that new world. Naturally, no one expects us to do the job single-­ handed. But each of us h ­ ere at Vassar needs to hang on to the conviction that college training is still directed ­toward a definite and serious end.”13 Since 1942, Vassar had implemented numerous mea­sures to save resources and to focus on the needs of the war effort. Cleaners and dining hall serving staff had departed to more essential jobs. An exact con­temporary of Vera’s (Anne MacKay), who also entered Vassar in 1945, wrote fifty-­five years ­later, “It was the end of World War II, so we all worked, swept corridors, cleaned bathrooms, waited on t­ ables and sat at the message center.”14 Curriculum changes had been introduced to offer teaching in subjects potentially of practical use in war­time, such as language translation skills, a physics course with focus on radio applications, and a meteorology course provided by the Department of Astronomy. The most significant development to affect Vera, however, was the decision in 1943 to offer an accelerated BA degree (or AB as it is formally called at Vassar) program lasting three years instead of the usual four.15 Many colleges had done this, with a view to conserving resources and more rapidly producing gradu­ates, who w ­ ere urgently needed in the workforce. Teaching took place over three terms each year, totaling forty weeks, rather than the usual two semesters totaling thirty weeks, and students ­were expected to work longer hours. The “a” and “b” terms ran for fifteen weeks from September through late December, and from January through mid-­ April. Then the academic year was extended by a ten-­week term (the c-­term), which followed a short recess ­after the b-­term. With the ending of the war, Vassar embarked on a comprehensive review of its curriculum but changes ­were not fi­nally introduced ­until the 1947–1948 academic year. No snap decision was made to end the accelerated program. The freshmen admitted in 1945, including Vera, ­were offered the choice of enrolling for e­ ither three or four years. Vera went for the shorter option. It promised to be less expensive overall, but no less rigorous or comprehensive. Term began on September 1. The opening of the year was marked with a formal Convocation, traditional rituals, pro­cessions and marches, and the singing of class songs. The Vassar Chronicle reported that freshmen ­were greeted at Taylor Gate by a white-­robed reception committee, received

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appointment slips for their interviews with the Dean, w ­ ere taken on a tour of the library, and had their photo­graphs taken for the college rec­ords. The president and his wife hosted after­noon teas on the lawn in front of their h ­ ouse. Home for Vera became a room in Cushing House, a residence hall built in 1927, its architecture based on a sixteenth-­c entury En­g lish cottage style. Rooms ­were simply furnished with a divan bed, a chest of drawers with a mirror, a writing ­t able, a desk chair, and a Windsor-­style armchair.16 Vera quickly settled into college life. The supportive atmosphere was a welcome change from the sometimes dismal and discouraging experiences she had endured in school. She was happy studying u ­ nder outstanding teachers alongside other young ­women who, like her, ­were keen to learn. She made friends, socialized, and took advantage of all Vassar had to offer. Within days of arriving she was signed up as a reporter on Miscellany News, one of the student newspapers, and she was assigned a room where she could practice the piano.17,18 Her con­temporary, Anne MacKay, remembered the feeling they all experienced: “We w ­ ere in love with the beautiful campus and the professors ­were excellent and exciting. . . . ​We wore sweaters, cut-­off jeans and men’s shirts—­but skirts ­were obligatory for dinner. . . . ​We had to deal with many rules about curfew, boys and alcohol.”19 Perhaps e­ ager to experience the freedoms they did have, and feeling at loose ends on one of the first weekends, Vera and three or four of her friends took to their bicycles and made the eight-­mile trip to Val-­K ill, the home of Eleanor Roo­se­velt. On arrival, their youthful enthusiasm emboldened them to knock on the door. To their surprise, they ­were let into the ­house, if only to be told that Mrs. Roo­se­velt was not at home. Vera admitted that they had made no plans for what to say if they actually met the distinguished former First Lady. Recollecting the exploit years ­later, she could scarcely believe they had been so audacious.20 The copy of Vera’s transcript preserved in the college files rec­ords all the courses that Vera took at Vassar, and the documents she submitted in 1948 with her application to Cornell University Gradu­ate School include summaries of what was covered in her astronomy, physics, and mathe­matics classes.21 Even though t­ here was no need for her to declare a major formally ­until her se­nior year, she made her intentions clear from the start. In her first year she enrolled for all the astronomy courses she could while shrinking from any physics. Her memory of the latter, as it was taught at Coo­lidge

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Fig. 2.2 A page from Vera Rubin’s photo a ­ lbum on which she taped a photo­g raph she took of the observatory during her first term at Vassar College in 1945. (Rubin ­f amily)

High, was all too fresh. She did not regard taking physics in her first year as essential to support her astronomical ambitions. She preferred mathe­matics and opted for analytic geometry and calculus. Between t­hese courses and the ones required of all freshmen in En­glish and a second language—­for Vera that was French—­physics could wait. Maud Makemson taught the freshman astronomy class, which ran on Mondays, Wednesdays, and Fridays for two terms. Vera worked her way through the course textbook, Astronomy, by William T. Skilling and Robert S. Richardson. Published in 1939, this introductory volume covered elementary

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celestial mechanics, the Sun and the solar system, dynamical properties of stars, and, in a single final chapter, the entirety of what was then known about “galactic and extra-­galactic nebulae.” When it first appeared in print, one con­ temporary reviewer’s opinion was that it “used language too s­imple and nontechnical for the readers for whom the book was written” and instead was “well adapted for the student who desires a knowledge of astronomy for its cultural value.”22 Vera found Makemson’s classes, however, quite technical, suggesting that the professor challenged her students beyond the level of their textbook. Vera remembered her mentor as “a very thorough teacher” who made a ­great effort to get to know her students and demanded high-­quality work.”23 ­There ­were practical exercises, too, on one eve­ning each week, weather permitting. The freshmen used a three-­inch brass telescope dating from around 1900 to make ­simple sketches of astronomical objects. It was the first opportunity Vera had to use a telescope other than her s­imple homemade one. She carefully preserved the notebook in which she made her drawings, including one of the Orion Nebula in white chalk on black paper, her sketches of lunar craters and Saturn with moons, and her colored diagram of the solar spectrum.24 From her second term, Vera became one of Makemson’s paid assistants, topping up her precarious finances by undertaking duties such as being “clock winder, paper grader, and telescope helper.”25 Once a week, Vera attended Maud Makemson’s first-­year class on the History of Astronomy up to 1900. Vera found the lectures truly inspirational and they added a new dimension to her interest in astronomy. As the text for this course, Makemson had chosen A Source Book in Astronomy, edited by Harlow Shapley and Helen E. Howarth, in which students encountered se­lections and extracts from the a­ ctual books and papers of the astronomers who made history.26 Photo­graphs of Makemson in her office at Vassar Observatory—­formerly Maria Mitchell’s drawing room—­picture her with terrestrial and celestial globes in the background.27 When one old globe was about to be discarded, Maud offered it to Vera.28 She accepted the gift, marking the start of a passionate interest in celestial globes and atlases that Vera would hold for the rest of her life. In March 1946, Vassar faculty de­cided to admit, as non-­residential students, men returning from war ser­vice who w ­ ere suitably qualified. The decision recognized the unfortunate shortage of college places for men across the country, given the glut of veterans whose education had been put on hold. Vassar’s charter did not allow it to grant degrees to men, but arrangements

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­ ere made for the credits they earned at Vassar to be transferred to other w institutions. O. Howard Winn was among the 152 men who studied at Vassar between 1946 and 1950. He had returned to Poughkeepsie from the Western Pacific in 1946. Although he could have taken up his deferred place at Dartmouth College, ­there was no dormitory space ­there, so his ­mother and ­sister, both Vassar alumnae, urged him to live at home and study at Vassar. In 2011, he wrote warmly about the “­great w ­ omen and g­ reat teachers” who had changed his life, including “Maud Makemson, in Astronomy, who gave me a job as a lab assistant (and found an interest in Astronomy and the Mayan Calendar perfectly compatible with an interest in creative writing).”29 Howard and Vera served their assistantships with Makemson at the same time. As the year’s end approached, Vera needed to get a job for the summer. When she went home for the spring break, she thought she had found one at the US Naval Observatory. She was even told what she would be ­doing and where she would be sitting. A ­ fter that break, however, she received a letter with the unwelcome news that ­there was no job at the Observatory ­after all. Vera’s ­father set about d ­ oing what he could to find her an acceptable alternative. Vera’s s­ ister had previously had a summer job in the library at the US Naval Research Laboratory (NRL), so Pete Cooper called to see ­whether t­ here might be something for Vera. Th ­ ere was. By the time she arrived home for the summer, the new job was waiting for her. The connection with NRL turned out to be fruitful for Vera. In three successive summers, she was given employment ­there. Although Vera’s job in the summer of 1946 had nothing to do with astronomy, it gave her useful experience of experimental science involving mea­ sure­ments and she found it “incredibly g­ reat fun.” She was placed with a research group in applied psy­chol­ogy. The proj­ect involved mea­sur­ing how quickly dif­fer­ent individuals physically reacted to a rapidly changing situation. ­There was a device to test reaction time and Vera had to interpret its output—­lines produced on a moving paper tape—as well as serve as test subject herself. When Vera returned to college, her requirements in French and En­glish ­were fulfilled. So she opted to take courses in ­music and philosophy while continuing with astronomy and mathe­matics. Her philosophy teacher was a spirited young man in his early thirties named Lewis S. Feuer, newly appointed as associate professor following his discharge from the army. He

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wrote prolifically through his long c­ areer and gained a considerable reputation for his diverse and wide-­ranging scholarship, particularly in the philosophy and sociology of science. A tribute written in 2012, the centenary of his birth, described him as possessing “not only a sophisticated theoretical intelligence but also an encyclopedic mind for historical and biographical detail, both of which w ­ ere always on display—­exhibited effortlessly and without ostentation—in his classes and public lectures.”30 Feuer was instrumental in kindling Vera’s lifelong interest in the history and philosophy of science.31 ­A fter a chance encounter with him in 1994, she nostalgically spoke of him as “my closest friend, ultimately, on the Vassar faculty.” Vera also found on her return for the second year that the astronomy courses w ­ ere being taught not by Professor Makemson but by Katherine Prescott Tinker, an instructor in astronomy. Tinker had been awarded a doctorate in celestial mechanics in 1933 by the University of California, Berkeley. As part of a coordinated international effort to determine the Sun’s distance as accurately as pos­si­ble, she had observed the near-­Earth asteroid Eros at Lick Observatory when it was especially close to Earth in 1931. Vera had previously been unaware of her, although according to the Miscellany News she had given a talk on “The History of the US Weather Bureau” in March 1944, the year she was appointed to the staff at Vassar. Although somewhat disappointed at the change, Vera did not complain about Dr. Tinker’s teaching. In fact, b­ ecause she did not have to account for herself to the rather formidable Makemson, she felt less inhibited about informally getting to know the seven-­and-­half-­inch refractor to which she had f­ree access. Made by the famed telescope manufacturer Warner and Swasey, with optics by John Brashear, it had been in the private observatory of Worcester Reed Warner, the com­pany founder, but was donated to Vassar College by his w ­ idow and installed t­ here in 1941. Vera found large glass photo­ graphic plates and chemicals in the darkroom. She “sort of made herself at home,” as she l­ater recalled. Was this what it might feel like to be an astronomer? Vera was photographed posing at this telescope, which continues to be used by students to this day.32 During the academic year, Vera plowed through two classic textbooks. One was Astronomy, by Henry Norris Russell, Raymond Smith Dugan, and John Quincy Stewart, first published in 1927. This book broke new ground as the first college text in En­glish to introduce the concept of astrophysics. With two revised editions, it remained the standard reference for college

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Fig. 2.3 Vera Rubin posing at the eyepiece of the telescope at Vassar College Observatory in 1948. (DTM, Car­n e­gie Institution of Washington)

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astronomy for around twenty years.33 It was complemented by William Smart’s ­Spherical Astronomy.34 In mathe­matics, Vera continued with analytic geometry and calculus but, ­going into 1947 and her next term, it was time to confront her estranged relationship with physics. She was almost halfway through her college courses and she needed credits in physics. She elected to take a course called Light, and another called Introduction to Atomic Structure, in hopes of stimulating her interest. Evidently that did not happen, given that even fifty years l­ater, in an oral history interview, the words “I ­don’t think I like physics” spilled out, like the confession of a lifelong guilty secret. Topics relating to light, spectra, and optics w ­ ere an exception, however, that she was prepared to concede. Since she aspired to be an astronomer and to use telescopes, knowledge of ­these subjects r­ eally was essential. At the beginning of March 1947, Vassar College hosted the first Eastern Colleges Science Conference, an event that has taken place annually ever since. The brainchild of a student who was president of the Science Club, it revived and extended the scope of the New York State Student Scientific Conferences which had taken place from 1940 to 1942 but then been discontinued b­ ecause of the war. The aim was to encourage undergraduate research and the exchange of ideas among the participating colleges.35 The theme of the first conference was “Science, Philosophy, and Society.” Several prominent academics ­were invited to give addresses, and twenty students had fifteen minutes each to pre­sent papers. Vera was one of five students from Vassar selected as a speaker. Although Vera’s pre­sen­ta­tion was based on the research of ­others, it was, in effect, her first scientific paper. The abstract, along with t­ hose of all the student papers, was published in the Yale Scientific Magazine, a scientific journal run by students of Yale University.36 The conference and the paper must have been of considerable significance to Vera b­ ecause she always kept the program, annotated with comments in her handwriting, and the fragile manuscript of her paper. Her talk was entitled “The Effect of Titanium Oxide on the Observations of an M-­t ype, Long Period Variable.” It was about the well-­k nown variable star, Mira. Listening to the talks of the other students was an early lesson for Vera in how to pre­sent a scientific paper, and she wrote down what she thought of her fellow speakers. “Too long and involved,” she complained about one on geology and geography. Observations of a partial solar eclipse w ­ ere

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“so-so.” A paper on welding was “OK but not in­ter­est­ing.” “Cartesians,” by a fellow Vassar student, she described as “Fun”—­a word that crops up time and time again when Vera is talking enthusiastically about science she enjoys. But her highest accolade was reserved for a paper called “The Solar Motion with Re­spect to the Red Stars.” It was “Marvelous!” From the moment Vera became aware of the stars from her bedroom win­dow, their movement through space would be a constant source of fascination for her. Two of the distinguished invited speakers w ­ ere phi­los­op ­ hers of science, Philipp Frank and Carl Hempel. Frank, who was Austrian, and Hempel, who was German, had fled from Eu­rope to the United States in the 1930s seeing the rise of Nazi influence. Both ­were associated with the “Vienna Circle” of phi­los­op ­ hers and scientists, so called b­ ecause of their meetings held at the University of Vienna u ­ ntil 1936. Both espoused a movement in philosophy known as logical empiricism. Hempel’s talk on the “nature of scientific explanation” clearly engaged Vera’s mind judging by the notes she scribbled on the program. “NO SCIENTIFIC QUESTION IS INCAPABLE OF (AT LEAST THEORETICAL) SOLUTION,” she wrote in bold capitals. At around this time—it is not clear ­whether during the conference or on a separate occasion—­the charismatic young physicist Richard Feynman paid a visit to Vassar and made an unforgettable impression on Vera. Although only twenty-­eight years old, he was already a well-­known and revered figure. Some fifty years l­ater, a poll of 130 of the world’s leading physicists would rank Feynman as one of the ten greatest physicists of all time.37 At the time of his visit to Vassar, he was a member of the physics faculty at Cornell University. ­Little did Vera imagine that, within two years, she would be studying quantum mechanics with him and he would be her official advisor for her studies in physics. When the academic year ended, Vera returned to Washington to live at home for the summer and to work again at NRL. It was an incredibly exciting place to be at that time. A research group ­there led by the physicist Richard Tousey had just made scientific history and Vera was ­going to be working in his lab. On October 10, 1946, they had gathered the first successful astronomical observations from beyond Earth’s atmosphere by blasting an instrument into space on a rocket. A second successful rocket flight followed on March 7, 1947. It was carry­ing a spectrograph, designed to photo­graph a part of the Sun’s ultraviolet spectrum that is invisible from the ground due to the absorbing properties of ozone and oxygen.

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At the end of the war, Amer­i­ca had yet to develop rockets of its own that could launch a significant payload above the atmosphere, but Germany already had that capability in the form of its V-2 rockets. On May 3, 1945, the genius engineer ­behind the German rocket program, Wernher von Braun, who had fled to Austria with his remaining technical staff, surrendered to the American army. They w ­ ere secretly moved to Fort Bliss on September 20, 1945, along with a hundred unused V-2 rockets and a supply of parts. Missiles built to carry warheads could equally be used to open up new frontiers in peaceful scientific research. Discovering more about the Sun was one new target. Among the prob­lems Tousey had to solve was how to funnel a narrow beam of sunlight into his spectrograph when the rocket was spinning and tumbling. His solution was to use a tiny transparent bead that would act like a fish-­eye lens, with a huge field of view. Glass would not do since it blocks ultraviolet radiation, just as the atmosphere does, so the beads w ­ ere made from a brittle crystalline material transparent to ultraviolet light: lithium fluoride. Among other assignments, Vera was given some of ­these beads and the task of investigating their optical properties. This exercise, she was sure, was not essential to the main proj­ect, but hopefully her findings would be useful supplementary information. In another proj­ect, Vera climbed up to the roof of the building to mea­sure the polarization of the light coming from the sky at dif­fer­ent a­ ngles and at dif­fer­ent times of day. That summer of 1947 at NRL was the best of the three Vera spent t­ here. “Just ­great,” was her verdict—­“incredible fun.” And ­there w ­ ere short-­term benefits for her. Vassar awarded her two credits t­oward her degree and, in the spring of 1948, Vera was able to pre­sent a paper on what she learned at NRL at the second Eastern Colleges Science Conference, which was held at Union College in Schenectady, New York. Fellow students learned about “Solar Spectroscopy from the V-2 Rocket” from her.38 The long-­term benefit to her training as an astronomer was her exposure to an entirely new field of astronomical investigation: rocket science, which allowed astronomers to survey the universe in the ultraviolet and X-­rays for the first time. In­ter­est­ing science made Vera very happy, but something ­else lifted the spirits of the nineteen-­year-­old that summer, too: she had been introduced to Bob Rubin and was falling in love. Bob’s parents w ­ ere neighbors of the Coopers in Trenton Terrace. Shortly ­after Vera went to college, her parents had moved from the rented h ­ ouse in Tuckerman Street where she grew up. The owner had put it up for sale and the Coopers could not afford to

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purchase it. Although scaled-­back building during the Depression and then the war had left Washington with a serious shortage of housing, the Coopers ­were fortunate. Vera had a friend whose wealthy f­amily had recently invested in an apartment complex development in southeast Washington called Trenton Terrace. The Coopers ­were offered a tenancy ­there. When newly built, this complex of 214 apartments was in an attractive setting and had a communal spirit all of its own. Twenty buildings of three-­ stories, with flat roofs, ­were arranged on a hillside. From many of the upper stories, t­ here w ­ ere views that seemed almost rural, across trees, an embankment thick with shrubs, and a brook. Karl Gerber, the developer ­behind Trenton Terrace, came from a ­family of Rus­sian Jewish immigrants who had settled on the east coast of the United States at the turn of the ­century, as Vera’s grandparents had done. Many friends and connections of the Gerber ­family from the Jewish community ­were among the early tenants, the Rubins among them. By the 1950s, Trenton Terrace would gain something of a reputation as a hotbed of left-­wing politics—­since Karl Gerber’s ­sister and brother-­in-­law, who managed the complex, ­were active Communists—­but the community was simply “one big happy ­family” for many who lived ­there. “Hallways and sidewalks w ­ ere only two of the many informal meeting spots,” reminisced one former resident. “The garden court out back was our town square.”39 In one such meeting place, in the early summer of 1947, Vera’s m ­ other and Bob’s ­mother fell to talking and introduced themselves. The conversation came around to something like “I have a d ­ aughter at Vassar,” and a response of “Oh—­I have a son at Cornell.” Soon ­after, Vera was back home and Rose Cooper invited the Rubin f­ amily over for the eve­ning. When Bob was introduced and Vera learned that he was a student at Cornell, her mind went immediately to one thought: “Do you know Richard Feynman?” Of course he did. ­Here in her own home she was meeting someone who was actually studying ­under the hero of her scientific dreams. That alone instantly made Bob attractive, but the rapport was mutual and more substantial. They continued to meet while they ­were both living at home in Trenton Terrace. Bob had a daily twelve-­mile commute to his summer job at the University of Mary­land, but before long he began making a special effort to meet Vera where she got off her bus. All too soon, the vacation was over. Vera went back to Vassar and Bob returned to Cornell. They ­were separated by two hundred miles. But their

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friendship had been no mere summer fling. The promises to keep in touch ­were genuine. On weekends, Bob hitched a lift or found some other way to make it to Vassar, by hook or by crook, to visit Vera. She had known very soon a­ fter their first encounter that she had met someone with whom she would happily spend the rest of her life. She and Bob ­were very much in love. At Thanksgiving in the fall of 1947, they announced their engagement, less than five months ­after they first met. Th ­ ere was a new passion in Vera’s life as power­ful as her desire to be an astronomer. Vera had done well in her second year. Shortly ­a fter she returned, she found her name was included on the Dean’s List of forty honor students in the class of 1948.40 Courses in art appreciation and po­liti­cal science ­were new territory for her in her senior-­year curriculum while she continued with ­music, alongside her studies in physics, mathe­matics, and of course astronomy. In early January, Maud Makemson wrote a glowing reference for Vera in support of her application for the position of gradu­ate assistant in the astronomy department at Cornell University: Miss Cooper has majored in astronomy at Vassar and at the same time has attained to advanced courses in mathe­matics and physics. Last year she acted as assistant in the eve­ning laboratory and observing classes, and this year she has been helping me with the time signals, the cata­loguing of exchange publications, correcting observing notebooks, making models for laboratory use, and in many other ways. I rely upon her as I would on a gradu­ate assistant, and I have indeed found her to be more intelligent, quicker, more in­de­pen­ dent and more reliable than some gradu­ate assistants I have had. At the same time it is a joy to have her around the observatory as she is always happy and good-­natured ­under all circumstances.41

This high praise notwithstanding, Vera’s relationship with Maude Makemson became strained in her final months as a student at Vassar, almost to breaking point. Makemson might have feared that the avowed ambitions of her protégée—­the only astronomy major in the class of ’48—­would come to nothing now that she was getting married, even though she was applying to gradu­ate school. Statistically, it was the most likely outcome at the time, even for Vassar gradu­ates who w ­ ere being educated to go out and change the world. W ­ omen generally expected to marry as soon as they came out of college, and for most ­women that meant forgetting any ­career ambitions they might have entertained. But Maud underestimated Vera’s

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determination. Nor did she know Bob. She could not envisage how a ­woman might “have it all”: a happy marriage, a f­amily, and a successful academic ­career. Maud had been married herself and had a son, but her astronomical ­career had blossomed only a­ fter her divorce. What­ever Vera’s f­uture prospects, however, it was the pre­sent that most concerned Makemson: she would not have liked seeing Vera distracted by Bob’s visits and not working as hard as she should. In her last term, Vera was the only student taking Makemson’s advanced course in celestial mechanics and she found herself in one-­to-­one situations where the strain between the two of them could hardly be contained. If Vera got something wrong, Makemson accused her of not working hard enough. Being forced to attempt mathematical derivations at the blackboard, which she frequently got wrong, was like torture. With her confidence already undermined, the relationship plunged to an all-­time low when Vera took her se­nior exam. A lone candidate, Vera sat in the examination room, faced with a series of tough prob­lems in celestial mechanics. She d ­ idn’t have to do them on the blackboard, but it was nearly as bad. Makemson, who was supervising her, walked by from time to time. This exam was impor­tant, and Vera felt the pressure. Then she encountered one question that stumped her. Was she being stupid when ­doing well ­really counted? Makemson saw her struggling with a prob­lem she should have found easy to solve. It is not hard to imagine the emotional reactions on both their parts when Makemson realized that the fault was her own: she had made an error in setting the prob­lem. She terminated the exam early and Vera was awarded an A. Vera and Maud Makemson ­were ­later reconciled and became good friends. When Makemson retired from Vassar in 1957, she wrote to Vera “on the millionth chance” that she would consider taking over Vassar College Observatory. “­There is no one whom I would rather see in charge of the department,” she put in her letter. “You are one of the won­ders of the world, raising such a darling f­amily, getting degrees and carry­ing on your interest in astronomy.” 42 Not a word ever passed between them afterwards about what happened in that difficult period at Vassar. Despite the tensions in her relationship with Makemson, Vera successfully completed all her senior-­year courses and a se­nior thesis on the star Gamma Cassiopeiae. By the end of just two senior-­year terms, she had ac-

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cumulated enough credits and high enough marks to allay her professor’s fears and gradu­ate as a Phi Beta Kappa inductee.43 Commencement weekend cele­brations began on Friday, May 14, with a banquet for the se­niors. Even the damp weather could not quell Vera’s excitement.44 The week before, Miscellany News had described the atmosphere and anticipated colorfully what was in store.45 “The trunks have been sent up from the storerooms,” wrote the reporter, “and elated se­niors are taking banners down from the walls, packing cherished mementoes, and closing notebooks with e­ ager finality.” ­Family and friends arrived Saturday to take part in vari­ous fun events, including a fathers-­versus-­daughters baseball game. In the eve­ning ­there was a choir concert in the chapel. Sunday’s program consisted of a ser­vice in the chapel attended by the se­niors in academic dress, a reception given by the president, and an eve­ning student play “with plenty of songs and laughter.” The climax of the weekend was the conferring of degrees in the chapel on Monday morning. Flagbearers headed the pro­cession of students, faculty members, and speakers. A student carry­ing a long-­stemmed American Beauty ­rose marshaled into order the 175 graduating se­niors from the class of ’48. Mark A. McCloskey, a Vassar trustee, gave the address. He was director of community education for the city of New York’s board of education and a recent recipient of the Presidential Medal for Merit.46 With all the ceremonials over and the benediction pronounced, Vera left the chapel, sheepskin diploma in hand, as a Vassar gradu­ate. Not quite twenty years old, she was about to be married and was heading into an exciting new phase of her life. Vera knew, however, that her diploma was not a passport into professional astronomy. Since arriving at Vassar, she had been plagued by self-­doubt, constantly wondering how she might chart a path into the ­career she felt was calling her irresistibly.47 The question ­Will I ever r­ eally be an astronomer? just w ­ ouldn’t go away and she could not imagine a f­ uture in which the answer was No.

CHAPTER 3

CORNELL AND THE ROTATING UNIVERSE

V

era and Bob’s wedding was on June 25, 1948. They had originally planned to marry in August but, when they ­were offered a rent-­free apartment in Washington for a few weeks and learned it would be available for the ­whole summer, they told their parents that they wanted to bring the date forward. This was a bombshell for Rose and Pete. Rose fretted that friends and neighbors might suspect Vera was pregnant. Pete was confounded by the practical prob­lems: planning was already well advanced, with the reception booked, deposits paid, and invitations printed. But once they had recovered from the initial shock, they warmly consented. Vera had another obstacle to clear. She was about to commence her third summer stint at the Naval Research Laboratory (NRL) on July 1. Initially, her request to defer for a week was rejected, but hearts softened when she explained that she was getting married. The honeymoon was delayed u ­ ntil they took a vacation on Block Island, about thirteen miles off the mainland of Rhode Island. Bob had come across this quiet hideaway with its sandy beaches and nature reserves during his war­time ser­vice in the Navy. At NRL, Vera was again placed with Richard Tousey’s group, where she had been the previous year. The work available was dif­fer­ent this time, however, and not as in­ter­est­ing to her. Now a gradu­ate, she was employed with the job title “physicist” and allocated an assignment involving FM radio in the context of naval communication. Given Vera’s interests, it is not surprising that the job did not turn out well. She was oppressed by a sense of not knowing enough to understand what she was supposed to be ­doing, and subsequently could recall very ­little about it. This was not Vera’s idea of fun!1 Still, it was a job: she was paid and the weeks passed quickly. She and Bob ­were together, and she was looking forward to being at gradu­ate school studying for a master’s degree.

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Fig. 3.1 Vera and Bob Rubin on their wedding day in June 1948. (Ruth Burg)

The previous November, before they officially announced their engagement while home for the Thanksgiving holiday, Bob and Vera had written to each other’s parents. Two identical letters ­were dispatched on November 8. They had been “poor correspondents,” they said apologetically, but now they ­were bursting to give the news of their intention to marry. In numbered lists, they set out their plans for the immediate f­ uture with answers to the kinds of questions that any parents of a c­ ouple of young students might ask u ­ nder such circumstances. What would they live on? Would Vera be sacrificing her chances to continue her education? Might it be more sensible to wait a ­couple

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Fig. 3.2 Bob Rubin in naval uniform, c. 1948. (Rubin ­f amily)

of years? They wrote confidently and enthusiastically, in no doubt that their devoted families would do every­thing they could to support them. Amidst addressing all sorts of practicalities, they interjected touchingly, “We are both terribly excited and happy about the ­whole t­ hing.”2 As a Navy veteran, Bob’s financial position was reasonably secure while he was a student. In 1944, a­ fter one year on a scholarship studying chemistry at Johns Hopkins University, he had enlisted in the US Navy and the Navy had de­cided he was a suitable candidate for its “V-12 program.” This scheme was created in 1943, in collaboration with vari­ous colleges and universities, to educate the large number of naval officers needed in war­time. Bob was sent to Cornell University to study chemical engineering in an accelerated bachelor’s degree program. As a V-12 student, he was paid $50 a month, required to wear a uniform, and put through rigorous physical training.3 As the war drew ­toward its conclusion, Bob was commissioned as an officer, although he had no wish to remain in the Navy in peacetime.

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­Under the Ser­vicemen’s Readjustment Act of June 1944, popularly known as the “GI Bill,” Bob could take advantage of a range of benefits, including having tuition and living expenses covered to continue with college studies interrupted by the war. This is what he did by electing to stay at Cornell. By 1946, he had gained enough credits to complete his work as an undergraduate. Initially he was registered for gradu­ate studies in the School of Chemical Engineering. That was problematic for Bob, who wanted to focus on his real interests in physical chemistry, physics, and mathe­matics, rather than engineering. In the spring of 1947, he transferred to the School of Arts and Sciences. In the fall term in 1947, he secured an assistantship, which he would eventually hold right through to the spring of 1951. Bob wanted to register for a PhD then, but he encountered an unexpected hiccup. Before his AB degree could be formally conferred, he was obliged to pass a course in German. He was fi­nally awarded his degree on June 16, 1948, just a few days before he and Vera w ­ ere married.4 The student c­ ouple expected they could manage financially. Vera felt confident she would get a paid appointment as a teaching assistant, while Bob banked on his entitlements u ­ nder the GI Bill, plus his pay as a teaching assistant in chemistry. Although the package added up, ­t here was still the issue of Vera’s continuing education. She had made a formal application for gradu­ate studies at Harvard University, in one of the most prestigious astronomy departments in the United States, then u ­ nder the chairmanship of Donald Menzel. Harvard was the obvious first choice for Vera. By contrast, the tiny astronomy department at Cornell was virtually unknown and had no rec­ord in research. Now, though, she needed to balance her priorities. Being apart from Bob and trying to maintain a long-­distance relationship between Cornell and Harvard would have been emotionally unbearable as well as hopelessly impracticable. One of them had to change their plans, and t­ here was l­ittle logic in Bob disrupting his studies yet again. He had e­ very expectation that he would be accepted formally as a doctoral student by the Gradu­ate School at Cornell as soon as the language requirement had been sorted out, and that he would be credited with the gradu­ate work he had already done as a “non-­candidate.” He estimated that he could complete his thesis with around two further years of work at Cornell. Vera could undertake gradu­ate work ­there. She had even been to see Professor R. William Shaw, who ran what astronomy t­ here was at Cornell, and had come

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away believing she would get a teaching assistantship in astronomy. She was brimming with optimism. ­There ­really was no question in Vera’s mind that Cornell was the right choice for her, so they rationalized the decision for the benefit of their parents with a list of compensations to set against any disadvantages for Vera. In par­tic­u­lar, living expenses would be much less and, unlike at Harvard, a teaching assistantship at Cornell would cover her tuition fees. They preferred not to be living in the midst of a large city and declared “nearby” New York as “much more beautiful than the Boston area.” Fi­nally, in case their parents needed any further softening up, they added that “­We’ll also have much more time to write home that way.” Vera wrote to Menzel to withdraw her application for Harvard’s gradu­ate school and a scholarship, explaining that she was getting married and ­going to Cornell. In due course the formal, typed acknowledgement came back. Menzel had added a handwritten postscript across the foot of the letter: “That’s the trou­ble with you gals!—­Get a good one ready for work—­and bang!— ­Off they go.—(I do not mean this unkindly, but merely as an expression of frustrated experience.)”5 Although not very delicately put, and undoubtedly somewhat offensive to Vera, this outburst of frustration was a fair reflection of what was typically happening at the time. On November 24, Vera submitted her application for admission to the Gradu­ate School at Cornell. She gave her reason for wanting to pursue gradu­ate studies as “to better equip myself for a research or teaching position in the field of Astronomy.” Monica Healea, professor of physics at Vassar, supported her application, describing Vera as “an excellent student with initiative and in­de­pen­dence” who was “in e­ very way a desirable candidate for gradu­ate school.” Healea recommended her unreservedly despite her studies in physics having been “somewhat irregular.” 6 Vera was accepted to study for a master’s degree. Unfortunately, almost as soon as she arrived at Cornell, Vera took an intense dislike to the chairman of the minuscule astronomy department, Professor Shaw. A very private and serious individual, he was not the kind of person with whom she could have an easygoing working relationship.7 A photo­graph of him, taken in 1942 and now in the Cornell archives, depicts the thirty-­eight-­year-­old Shaw as dapper in a three-­piece suit and captures his formal manner. His short dark hair is neatly sleeked back and he wears steel-­rimmed spectacles. His neutral expression is carefully composed.8

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Shortly ­after Vera arrived, he suggested to her that she might be better off studying something other than astronomy, as astronomers ­weren’t needed. Perhaps it was an awkward attempt to offer well-­meaning advice, but to ­Vera’s ears it sounded as if he ­were trying to get rid of her. She was not the kind of person to be put off that easily. With the same resilience of character that carried her through physics at school, she dismissed Shaw as someone who simply d ­ idn’t understand her. She would nevertheless need to get along with him somehow ­because she was reliant on her job as his teaching assistant. Shaw, for his part, must have thought quite highly of Vera; in his first report on her pro­gress, in the fall of 1948, he described her as a “superior student.”9 Although the astronomy department at Cornell had no reputation for research, several hundred students w ­ ere taking elementary courses each year. The department had its origins in civil engineering. Estevan Fuertes, the first professor of civil engineering, built the first observatory between 1876 and 1882. It ­housed the instruments used to instruct engineering students how to determine time and position by observing the stars. The current Fuertes Observatory on the northern side of the university campus was completed in 1917. A twelve-­inch telescope constructed by the firm Warner and Swasey, with optics by the John A. Brashear Com­pany, was installed in 1922 and it’s still ­there. The building, designed to accommodate an office, a classroom, and other facilities, has remained much as it always was.10 In 1933, astronomy, embodied by a single faculty member, Professor Samuel L. Boothroyd, moved out of civil engineering to become a department in the College of Arts and Sciences. Office space was found in the physics department. The department doubled its complement of faculty from one to two in 1939 when Shaw was appointed assistant professor, a promotion from his position as instructor in the physics department, where he taught spectroscopy. He took over as chair of the department and director of the Fuertes Observatory on Boothroyd’s retirement in 1942.11 Shaw’s main preoccupation, like Boothroyd’s before him, was teaching, at which he excelled. In 1942, Shaw and Boothroyd wrote a Manual of Astronomy, which at first was printed privately at Cornell for students to use, then published in 1947.12 It was a complete guide to all the observational and laboratory exercises in elementary astronomy that students w ­ ere required to do, and Shaw revised it twice more a­ fter publication, in 1958 and 1967. Vera became very familiar with this manual as she was placed in charge of the laboratory work in Introductory Astronomy.13

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Vera’s pre­de­ces­sor as teaching assistant had been an undergraduate, Joyce Marrison, who completed her BA degree and left Cornell in 1948. No doubt, Shaw would have anticipated the forthcoming vacancy when Vera first presented herself back in the fall of 1947. Marrison was off to Harvard where she had been awarded an Edward C. Pickering Fellowship.14 This program, to assist w ­ omen who wanted to pursue studies in astronomy at Harvard, had been endowed in 1916 by the Maria Mitchell Association in honor of the then director of Harvard College Observatory, who had been a pioneer in employing ­women. It is likely that Vera had originally hoped to secure one of ­these fellowships, before her change of plan. As if to prove Menzel’s generalized complaint to Vera about w ­ omen students, at Harvard, Marrison met and married Gordon Newkirk, a fellow student. When he moved to the University of Michigan in 1950, she went, too, and according to Newkirk she left astronomy two or three years afterward without completing her doctorate.15 In 1948, when Vera succeeded Marrison at Cornell, the teaching of physics and astronomy at Cornell was still in the pro­cess of recovering from war­ time disruption. Key faculty members in physics had temporarily left their regular research to undertake work for the military, and Cornell had taken on a substantial V-12 training program, teaching subjects such as navigation to naval recruits. With the war over, physics sprang back to life. Many of the teaching and research staff returned, and new upcoming talent joined the department—­including Richard Feynman.16 In astronomy, Dr. Martha E. Stahr (who would become Dr. Martha Stahr Carpenter ­after her marriage in 1951) had joined the department as assistant professor at the beginning of 1947.17 She was the first female faculty member to be appointed in Cornell’s College of Arts and Sciences. Stahr was immediately designated as the astronomer to work with the electrical engineering department on a new observational radio astronomy proj­ect that made use of a former army radar dish. This first venture by an American university into radio astronomy followed the trend ­adopted by physicists in Britain and the Netherlands, to repurpose radar technology for astronomical purposes. At Cornell, however, this pioneering research was beset with delays and administrative prob­lems. Overcome with frustration, Stahr began work on an all-­consuming personal proj­ect that she could carry out on her own. Her aim was to compile a complete bibliography of the science and engineering lit­er­a­ture relevant to radio astronomy.18

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Stahr was a ­woman a­ fter Vera’s own heart. Her interest in astronomy had begun when she was fourteen years old. A ­ fter school, she went to Hood College in Mary­land, where her f­ ather was president. Within a year, as she put it, “it suddenly dawned on me that I could actually become an astronomer.” So she transferred to Wellesley College, where she could major in the subject. Like Vera, she yearned for a telescope: she ground and polished her own mirror and built one that she used to observe variable stars. As Vera would ­later experience, Stahr encountered prob­lems when she wanted to use a large, professional telescope—­t he thirty-­six-­inch refractor at Lick Observatory. ­There ­were questions about w ­ hether “a ­woman could h ­ andle it.” In response to t­ hese, “I just went up ­t here,” she ­later recounted. “The man was ­t here ­doing all he could to ­handle it and it ­wasn’t before long that I was ­doing it with him.” Making good use of observations at Lick, she completed her PhD in 1945.19 It seems, though, that Martha Stahr did not converse with Vera about her own early experiences. ­There was no big age difference between them—­ only eight years—­but they never formed a social relationship. Perhaps that was ­because Vera was newly married and wanted to be with Bob, rather than due to any reservation on Stahr’s part. As Vera put it, “I just went in and did my work and left.” Professionally, however, the relationship worked well. Martha was a good teacher and, as Vera’s master’s thesis advisor, she was supportive and always accessible. When she was not teaching she could invariably be found in her office, working on her bibliography. Twenty-­three years ­later, Vera, who by then had become more distinguished than Stahr, recommended her former teacher for tenure at the University of V ­ irginia. “She continually made me want to learn and gave me the confidence that I could learn on my own. A real talent in a teacher,” Vera told the chair of the department.20 Although the four-­person astronomy department at Cornell was insignificant, the opposite was true of the large physics department where Vera attended many of her classes. It boasted three physicists of international repute: Richard Feynman and Hans Bethe, who ­were both ­future Nobel laureates, and Philip Morrison. Richard Feynman was the undisputed star, and the official physics advisor to both Vera and Bob. Along with his brilliance (he won the 1965 Nobel Prize in Physics for his work in quantum electrodynamics) he was always the showman, a performer with a colorful character and a loud, boisterous manner.21 Vera’s hours as an astronomy lab

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assistant clashed with the class times for first-­year gradu­ate students in physics, so Feynman suggested she enroll in his quantum mechanics course. She jumped at the opportunity: Bob happened to be taking that course at the same time. Despite the celebrity and encouragement of her teachers, Vera was still not strongly attracted to physics. Being the only student in the class who had not majored in physics, she felt like an outsider. The physics she had ­under her b­ elt from Vassar had not prepared her for the demands of Feynman’s lectures on physics. Bob stepped in as Vera’s most impor­tant guide and teacher. She talked to him all the time, not only for close emotional support but also as a valued scientific colleague. He was, she acknowledged, “a much better physicist” than she was. By contrast, classes in astronomy had ­great appeal for Vera. Although she had a low opinion of Professor Shaw, she conceded that his course on “astrochemistry,” mainly about his primary interest of spectroscopy, was quite good. But above all, Martha Stahr’s three classes called The Galaxy, Advanced Galactic Structure, and External Galaxies had lasting impact. For her own doctorate, Stahr had investigated the dynamics of our Milky Way galaxy by mea­sur­ing the speeds with which certain stars located well above or below the disk of the Galaxy appear to be receding from the solar system. Stahr’s impressive grasp of galactic dynamics stimulated even more strongly Vera’s long-­standing fascination with star movements.22 As a young girl, Vera had observed how Earth’s rotation makes constellations of stars seem to sweep around the sky daily. What she could not detect was any shift in the relative positions of the stars. That’s ­because constellation patterns do not change noticeably, even in the course of a lifetime; only high-­precision mea­sure­ments made over a long period reveal that stars ­really are creeping across the sky. They go so slowly that the distance they cover, if detectable at all, is mea­sured in seconds of arc per year. When combined with a star’s distance, this “proper motion” translates into a real speed through space, in kilo­meters per second. But that is still not the full story. Any star is very likely to have an ele­ment of movement ­toward us or away from us, as well as across our line of sight. That “radial” component of its motion shows up clearly in a star’s spectrum as a systematic blue shift or red shift. In princi­ple, an astronomer can find the true speed and direction of travel of a star in space by mea­sur­ing, its distance, its proper motion and its radial velocity. In practice, it was a long and difficult pro­cess over

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de­cades for astronomers to collect accurate data of this kind on a large number of stars. Despite ­these prob­lems, the evidence that the Milky Way galaxy revolves about a center some thirty thousand light years away from the Sun, in the direction of the constellation Sagittarius, gradually built up from the beginning of the twentieth c­ entury. Prominent among ­those who contributed to this research on the internal motion of the Galaxy was the Dutch astronomer Jan Oort, who would l­ater become Vera’s close friend and colleague. In 1927, Oort had used relatively ­simple mathe­matics to describe the basic characteristics of how the Galaxy is turning in the Sun’s locality.23 Importantly, all the quantities in his formulas are properties of stars that can actually be mea­sured. Vera taught herself how Oort’s analy­sis worked. When she started her gradu­ate studies, however, astronomers still lacked indisputable evidence that the Milky Way ­really was a spiral galaxy. It was suspected to be spiral b­ ecause astronomers surmised that the Milky Way was prob­ably a close cousin of its nearest large spiral neighbor, the Andromeda Galaxy. It took ­until 1951 to ­settle the m ­ atter.24 The work of Oort (and ­others) revealed that individual stars in the Galaxy, along with gas clouds and star clusters, stream around the center of the Galaxy following their own orbits, although at dif­fer­ent rates according to how far they are from the heart of the Milky Way. To complicate m ­ atters, on top of the general streaming, stars often wander around in their own locality and some follow orbits that defy the general streaming altogether. But with data on enough stars, the overall streaming trend stands out above all the random mavericks and rogue stars. Deciphering how a galaxy is rotating when you live inside it is a challenge, but it can be done. When Vera needed a topic for her master’s thesis, she was taken by the idea that techniques similar to t­ hose Oort had applied to detect the rotation of the Milky Way could be used to see if galaxies share a streaming motion as they revolve around some remote hub in the universe. It was an in­ter­est­ing question to ask in princi­ple. In 1946, George Gamow—­who several years ­later became Vera’s doctoral advisor—­had published a short article in the prestigious science journal Nature headed with a two-­word question: “Rotating Universe?”25 Gamow wondered why ­every kind of entity in the universe appears to be rotating. The rotation of stars and planets can be explained by the fact that they formed from nebulae that w ­ ere already spinning, but this tendency for galaxies to rotate must have been inherited

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from somewhere. Where? Maybe, he speculated, “all ­matter in the vis­i­ble universe is in a state of general rotation around some center located far beyond the reach of our telescopes.” Was the ­whole universe born spinning? If galaxies are part of some vast, rotating supersystem, a study of their radial velocities could in princi­ple provide the evidence. Gamow quoted the “so-­ called Oort-­effect” seen in the observed motions of nearby stars due to the rotation of the Milky Way and he suggested that “careful observations of mean radial velocities of galaxies located in dif­fer­ent regions of the sky should reveal similar periodicity.” Vera l­ater maintained that she simply could not remember w ­ hether or not this note in Nature gave her the idea for her thesis. It is certainly plausible that it was the spark that set her thinking, and Gérard de Vaucouleurs, with whom she corresponded frequently in the 1950s thought it probable that it was, but neither Vera’s recollections nor anything written nearer the time tells us for certain.26 She recalled only that Bob drew her attention to it. Although her advisor, Martha Stahr, went along with the idea and supported Vera as best she could, it was not pos­si­ble for Vera as a student to undertake her own observing program with a large enough professional telescope. And in any case, the planning timescale for arranging such observations was much too short. Vera’s thesis proj­ect therefore had to be on a topic that she could investigate with published data already obtained by ­others. Knowledge of the speeds and distances of galaxies was still very sparse in 1949. Vera thought, however, that ­there might be sufficient data at least to give it a try, by developing her method and seeing what it produced. For that she needed radial velocities determined from the red or blue shifts of galaxy spectra. Th ­ ese she took from a ­table published in 1933, as ­there was nothing more up-­to-­date available. It gave her a total sample of 108 galaxies.27 By the late 1940s, redshift surveys had been in pro­gress for years at the Mount Wilson Observatory and at Lick Observatory, but the results had not been made public. A request made on Vera’s behalf by Martha Stahr for access to unpublished mea­sure­ments produced only a response that the data would be “published soon.”28 As it turned out, the paper containing the data did not materialize ­until 1956.29 For in­de­pen­dent distance estimates, Vera ­adopted the simplistic approach of calculating them from the overall apparent brightness of each galaxy. To have any chance of detecting rotation, Vera first needed to subtract the substantial contribution to the motion of each galaxy made by the gen-

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eral expansion of the universe. She found, as expected, that some of the residual velocities ­were directed t­ oward the Milky Way (negative values) and some away from it (positive values). Representing each of the galaxies by a plus or a minus symbol accordingly, she then searched for a pattern in the way the symbols ­were distributed over the sky. As part of her analy­sis, she also needed to identify a reference plane where galaxies are most concentrated—an equivalent of the plane of the Milky Way where most stars congregate. Although she worked with very ­limited data, Vera extracted answers to the questions she asked. Her master’s thesis was entitled “Evidence for a Rotating Universe as Determined from an Analy­sis of Radial Velocities of External Galaxies.” For a student of ­limited experience, who had no contact with astronomers outside her own tiny department, it was a bold proposition. In the spring of 1950, Shaw’s report about Vera was a ­simple statement: “Excellent pro­gress on a very original thesis.”30 Vera’s oral examination for the master’s degree was scheduled for June 1950. The committee consisted of Professors Shaw, Stahr, and Feynman. ­A fter reading Vera’s thesis before the oral took place, Shaw spoke to her about it. He had two comments. He told her that “data” was plural: she had wrongly treated it as singular and would need to correct the error throughout. More significantly, he told her bluntly that her work was “sloppy” (or something to that effect) and that she ­didn’t pay enough attention to the details. Then, ­after the put-­down, he surprised her by saying that, ­later in the year, a paper on her work might nevertheless be presented orally at the December meeting of the American Astronomical Society (AAS), which would be in Haverford, near Philadelphia. If momentarily Vera thought Shaw was being positive and supportive ­toward her, what came next shocked her. Vera was expecting her first child in October or November. Of course, Shaw added, she w ­ ouldn’t be able to go to the meeting, as a new ­mother—­and, in any case, she was not a member of the AAS. He would therefore submit the paper, and not with Vera as author (as she understood it) but in his own name! With ­great presence of mind Vera spoke up: “Oh, I can go.” Exactly how the trip would be achieved she would have to work out l­ater, but one way or another she was in no doubt that she would make it happen. She had her ­family to turn to. What was in Shaw’s mind remains a mystery. Did he r­ eally want to encourage Vera, or did he think he could use her imaginative proj­ect to promote himself and the Cornell department? Was he just old-­fashioned in his attitudes? What­ever was ­behind his suggestion, having made it he

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could not then prevent her from ­going in person to deliver the paper when Martha Stahr, as an AAS member, submitted it on Vera’s behalf. It proved to be a memorable and formative event. The oral examination did not take place in June as planned. Without a word to Vera, Feynman took off for summer travels the week before. A new date in October was eventually scheduled, with Philip Morrison taking the place of Feynman. Meanwhile, with her coursework completed, Vera had no reason to be at the university and she was no longer being paid as an assistant. She and Bob moved to Trumansburg, about twelve miles northwest of Ithaca. One of Vera’s u ­ ncles had set up a leather business t­ here, and they ­were able to save money by lodging with him. Vera had l­ittle to do but prepare for her oral examination and her ten-­minute talk at the AAS meeting—­and to think about what the ­future might hold for her. Her wish to have a ­family was soon to be fulfilled, but she still had a question constantly on her mind: ­Will I ever ­really be an astronomer? She passed the examination on October 2, and eight weeks ­later, on November 28, her son David was born. The remaining milestone in this eventful year was the AAS talk she was to give just one month l­ ater, on December 28. Vera had never been to such a meeting. She had not interacted with any of the prominent ­people in the world of professional astronomy and had ­little idea of what to expect. She was still only twenty-­t wo years old. All the same, she felt a degree of confidence. She prepared very carefully, memorizing what she intended to say, and made slides of seven diagrams. Instead of her long thesis title, she de­cided on something snappier for the short paper: “Rotation of the Universe.” The practical arrangements for getting to the meeting and caring for baby David required meticulous planning, which concerned Vera almost as much as preparing her paper. By a stroke of luck, this par­tic­u­lar meeting was at Haverford College in Pennsylvania, only ten miles from her grand­mother’s home in Philadelphia. But Trumansburg is 250 miles from Philadelphia, and Bob and Vera had no car. As always, the f­amily rallied round and found a solution. Vera’s ­father would provide the chauffeur ser­vices. Vera, Bob, and baby David could stay at her grand­mother’s h ­ ouse. And Vera’s m ­ other and aunt would care for David while Vera went to give her talk, allowing Bob to accompany her. A few days before the meeting, Pete and Rose Cooper drove from Washington to Trumansburg. Then with Vera, Bob, and their first grand­

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child in the back of the car, they set out for Philadelphia on what would prove to be a nightmarish journey. The route took them over the Pocono Mountains, an upland area extending across the north of Pennsylvania. And it snowed. Pete felt as if he had aged twenty years by the time the five of them arrived. The wintry weather was bad enough to be one of the main topics of conversation among the astronomers gathering at Haverford College.31 The two-­day meeting started on the morning of December 28, when Vera was scheduled to give her talk. The day before, Vera’s ­mother and aunt took her shopping. They judged—­correctly—­that a new dress would boost her self-­confidence. At Haverford College, meanwhile, meeting attendees w ­ ere arriving and the early birds ­were entertained with a planetarium demonstration during the after­noon. The AAS Council met at 7 pm. One of its jobs was to approve the list of scientific papers to be presented over the next ­couple of days. It was normally just a ­matter of “rubber stamping.” But this time ­there was a question over one of the papers—­Vera’s. It was only forty years ­later that someone pre­sent at that council meeting (Frank Kerr) revealed to Vera that the council had debated at length ­whether her paper should be accepted onto the program. Hers was one of only two papers among the entire forty-­nine submitted on a subject concerning galaxies beyond the Milky Way. And ­here was a young, unknown student from nowhere, claiming she had evidence that the locally observed universe was rotating about a remote center of motion. What an audacious claim! What­ever the reservations of some of its members, the council acted liberally by deciding that Vera should give her ten-­minute pre­sen­ta­tion. The morning of December 28, Vera’s ­father drove her and Bob to Haverford College in time for her scheduled slot. During the ten-­mile journey, Vera continually went over in her mind what she would say. The scientific sessions w ­ ere taking place in a large lecture room in the Haverford Union Building. One of the AAS vice presidents, Dirk Brouwer, was presiding.32,33 At the front of the room ­there was a low-­rise platform. Vera stepped up, went to the lectern on the left, and faced her audience. She was confronted by around 130 ­faces, mainly male, entirely of p ­ eople considerably older than her. They sat in rows of sixteen with an aisle down the center.34 The assembly in front of Vera represented “the establishment” of American professional astronomy. She could not identify a single individual by sight. Undaunted, she launched in and gave the talk as she had rehearsed it.

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From her Cornell experience, Vera was accustomed to tough questioning by world-­class professors, but she was hardly prepared for the criticism she now faced. In her words, the discussion that followed her pre­sen­ta­tion was “rather acrimonious.” The graphical methods she used w ­ ere not rigorous enough, complained her critics—­and why had she not quantified the likely errors in her results? Out of the blue, a small man with a high-­pitched voice piped up. His tone was more kindly. “This is a very in­ter­est­ing ­thing to have attempted. The data may not be quite good enough and so forth, but it was in­ter­est­ing.” Vera did not know that the man who had leapt to her defense was Martin Schwarzschild. Since 1947, Schwarzschild had been a professor at Prince­ton University, where he would go on to have a distinguished ­career, mainly as a theorist.35 Brouwer fi­nally ­stopped the discussion on Vera’s paper by calling for a coffee break. Before she could slip away, he caught up with her. He was the editor of The Astronomical Journal, where abstracts of papers presented at the meeting w ­ ere published. “I’m sorry,” he said, “we c­ an’t publish an abstract entitled ‘Rotation of the universe’ so I ­will call it ‘Differential rotation of the inner metagalaxy.’ ” The term “metagalaxy,” introduced in the 1930s, was widely used at that time to mean the general population of galaxies in the universe. Brouwer ­didn’t ask Vera’s opinion about the title and t­here was no discussion. “Fine, thank you,” was all Vera could say. And she left without even ­going for coffee. By this time, her primary concern had switched to how baby David was ­doing. As for the paper, despite the negative comments, overall she thought that she had delivered it well and she felt quite satisfied as she walked out. That eve­ning, Harlow Shapley, one of the most distinguished astronomers in the United States, gave a keynote lecture on “The Inner Metagalaxy.” Vera was not entitled to attend since she was not yet a member of the AAS, but she would surely have found it compelling, given the subject of her own paper. Despite her early departure from the meeting, however, she had left an impression. Her debut on the astronomical stage provoked a flurry of interest and stuck for a long time in the minds of many who heard her. Somewhere in the audience ­there was a reporter from the Washington Post who ­couldn’t believe his luck: something r­ eally newsworthy had turned up at an other­wise rather run-­of-­t he-­mill meeting. He diligently took notes, trying to capture both the essence of what Vera was saying and the atmo-

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sphere of the meeting. On December 31, the newspaper ran the story ­under a headline that would become a r­ unning joke in the f­ amily: “Young M ­ other Figures Center of Creation by Star Motions.” It described her pre­sen­ta­tion as “so daring that most astronomers think her theories are not yet pos­si­ble,” taking care to caution that astronomers in the audience “­were not complimentary. They politely and per­sis­tently questioned her figures, b­ ecause ­there are not enough sure observations to substantiate them. She replied that it is worthwhile to try.” By the next day, January 1, 1951, the Washington Post had caught up with the fact that Vera was from a Washington ­family. A followup piece, “Student Whose Theory Amazed Astronomers is D. C. Resident,” included a photo­graph of her at the telescope from her Vassar days. For Vera it was “unexpected but fun” to be the focus of media attention, but it was the science and the impact her appearance at the meeting would have on her ­career that she r­ eally cared about. Around three weeks ­after the meeting, Schwarzschild sent Vera a very polite letter, asking for more details of her analy­sis.36 Photocopiers ­were still a technology of the f­uture and Vera had no spare copy of her manuscript. What copies she possessed had been sent off in the hope that one of the principal American journals would accept it for publication. So she replied explaining the situation and offering some additional information about what she had done.37 In due course, the manuscripts came back from the journals, whose referees ­were as critical as her live audience had been. Her paper was rejected by both The Astrophysical Journal and The Astronomical Journal. The abstract remains the only published rec­ord of her talk.38 Schwarzschild ­wasn’t the only astronomer who took Vera seriously. Another of ­those who had heard her speak was the director of the University of Arizona’s Steward Observatory, Edwin Carpenter. He wrote to Vera soon ­after he got back to Arizona, explaining that he, too, was interested in the large-­scale structure of the distribution of galaxies.39 ­A fter the abstract was published in April 1951, she also heard from two astronomers who had not been at the meeting. One was the Soviet astrophysicist Kirill Orogodnikov, a professor at Leningrad State University. He wrote from the USSR to tell Vera that he had been working along similar lines. The other was a young French astronomer working at Mount Stromlo Observatory in Australia: Gérard de Vaucouleurs. His letter was the start of what Vera called “a relentless, questioning correspondence that forced me to learn more and to face prob­lems whose troublesome existence had not

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previously both­ered me.” 40 Eight years in the f­uture, Vera would find herself collaborating with Gérard as his research assistant. More than a year l­ater, ­after Vera had enrolled to study for her PhD at Georgetown University, Schwarzschild had not forgotten about her. On hearing through George Gamow, who was by then Vera’s thesis advisor, that her paper on the rotation of the inner metagalaxy had run into difficulties with journal referees, he asked again for a copy—­and this time he got it. He had said he would try and help her to get it published, but on August 20, 1952, he wrote to Vera suggesting that her best course of action was to concentrate on her PhD thesis work. “The main purpose of your rotation work must have been to pointedly draw the attention of astronomers to this impor­ tant prob­lem and to make yourself a first stab at it,” he wrote. “Both you have successfully done by your pre­sen­ta­tion at the Haverford meeting and by the publication of the abstract.” He offered further words of encouragement: “That the technique of your analy­sis has not quite stood up u ­ nder the critical eyes of some of the referees should not surprise or discourage you in the least. The topic you had selected for your first work is exceedingly fascinating and impor­tant indeed, but it is also exceedingly tricky and it ­will take quite a lot of experience with this type of uncertain statistical data before one’s methods ­will take care of all the ifs and buts.” 41 Schwarzschild himself would prove to be a g­ reat scientist, and h ­ ere he recognized in Vera’s earliest endeavors the qualities of curiosity, imagination, and courage that would underpin the ­whole of her scientific c­ areer. Vera never forgot Schwarzschild’s kindness. In 1986, she chanced upon that 1952 letter while searching for something ­else in her attic. She wrote to thank him again, thirty-­four years on. “Your concern for young astronomers has been a remarkable role model for many of us. I hope that somehow Astronomers ­will learn to retain some of their humanity and gentleness, even as the work gets more and more competitive. You have shown that it can be done.” 42

CHAPTER 4

GEORGETOWN, GAMOW, AND GALAXIES

A

t the start of 1951, Vera’s pro­gress ­toward achieving her c­ areer ambitions had shuddered to a halt. Within days of the AAS meeting in Haverford, she was sure of what she had already r­ eally known in her heart: to be considered a true professional in astronomy, she would need a doctorate. Yet as ­things stood, reentering gradu­ate school seemed impracticable, l­ittle more than a hazy dream in a far-­off, uncertain f­ uture. She and Bob had de­cided to let m ­ atters drift along for now and to wait for what might unfold in the ­future. Bob would need ­until the summer of 1951 to complete his thesis. Then he would need a job. Who could foresee where they might be in a year’s time? Meanwhile, Vera had a new son to care for. Being a m ­ other was a joy, and she and Bob ­were already looking forward to having more ­children. Surely she would be busy enough with young Davy for the time being.1 Bob passed his final PhD examination in June 1951 and a number of job offers followed. One of them, from the Applied Physics Laboratory (APL), appealed particularly to both Bob and Vera. This research establishment, affiliated with Johns Hopkins University, was located in the Washington area where Vera’s parents lived. Having the c­ hildren’s grandparents nearby to help would give Vera the best chance of resuming her gradu­ate work in due course. It also appealed to Bob to join such a prestigious institution; APL employed some of the brightest young physicists around. The ­matter was settled. One of the consequences of this decision for Vera was her first professional encounter with George Gamow, which ultimately led to his becoming her thesis advisor. Understanding how the encounter came about, and the nature of the professional relationship that developed between Gamow and the young Vera, starts with knowing some of the story of APL and background of Gamow’s ­career. At that time, APL was in Silver Spring, Mary­land, just to the north of the district. It owed its existence to frantic war­time efforts to perfect in

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secrecy a crucial military invention known as a proximity fuze. This smart device automatically detonated a missile when it was close to its target, even without a direct hit. It was something the military had desperately wanted for combating the growing threat from ­enemy aircraft. The National Defense Research Committee selected Merle A. Tuve, a physicist in the Department of Terrestrial Magnetism (DTM) of the Car­ne­gie Institution of Washington, to lead the research team.2 By 1942, the proximity fuze proj­ect had massively outgrown the space DTM could offer and needed its own home. ­Under a deal with Johns Hopkins University, a new secret research organ­ization was born, for which Tuve coined the name “Applied Physics Laboratory.” The premises chosen to h ­ ouse the undercover operation had a ready-­made disguise. A second­hand car business had occupied the space previously and the building still displayed a large sign proclaiming USED CARS. Its upper floors had recently been used as social security offices, so the comings and ­goings of government employees ­didn’t attract par­tic­u­lar attention. Hidden away in this suburban backwater, APL’s researchers soon homed in on their objective. Industrial-­scale manufacturing of the first-­generation fuzes began in late 1942 and, by the end of the war, twenty-­two million had been produced. APL, along with DTM, was credited with one of the most impor­tant developments in war­time military technology. Remarkably, it remained one of the Allies’ best kept secrets throughout the war. At its conception, APL was envisaged as a temporary organ­ization, just for the duration of the war. As it turned out, the pioneering research ­there, especially in new missile technology, was just as vital a­ fter the war ended. ­Under Tuve, the laboratory had gained an international reputation as “an institution that could do the impossible.”3 So APL was kept g­ oing and broadened its scope. Merle Tuve himself moved back to DTM in 1946 to become its director, but not before securing the financial ­future for the team of brilliant scientists he had assembled. Nineteen years ­later, Tuve would offer Vera a job at DTM. In 1951, the ever-­expanding APL still occupied its used-­car garage, by then with assorted extra buildings added on. In ­these unlikely surroundings, the laboratory now incorporated a world-­class center for fundamental research in such topics as aerodynamics, the properties of materials, combustion, and spectroscopy.4 The outstanding scientists on the staff at the APL Research Center, where staff worked on fundamental academic research, included

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Ralph Alpher and Robert Herman. Both had been hired by Tuve during the war. When Bob arrived, Herman had become head of a molecular spectroscopy group and Alpher was occupied with supersonic gas dynamics. At least, that was what they did during the day and w ­ ere paid for. But it was the ­science they did as a hobby in their spare time that eventually won them international recognition. Th ­ ese two men shared an informed interest in cosmology and astrophysics and in 1948 they found themselves following up a groundbreaking line of research. When Bob was considering APL’s job offer, Vera already knew of Alpher and his early excursions into astrophysics. His 1948 PhD thesis on the origin of the chemical ele­ments had created something of a sensation when he first presented it to an audience of three hundred at George Washington University (GWU), where he was a student. ­Those listening included not only his examiners but press correspondents—­and it had the news wires abuzz for weeks. Vera remembered hearing him give a talk on his thesis work at the Washington Philosophical Society.5 Ralph Alpher had earned his bachelor’s, master’s, and doctoral degrees in physics at GWU by studying in the eve­nings while making his living as a full-­time physicist working mostly on US Navy contracts, first at DTM and then, from 1944, at APL. At GWU, his gradu­ate work was supervised by George Gamow (1904–1968), whose letter to Nature about the rotation of the universe Vera had seen when writing her master’s thesis. Gamow’s life story begins in the Rus­sian Empire with his birth in Odessa. At school he took an interest in the stars, and on his seventeenth birthday his ­father gave him a small telescope. Following his undergraduate course in mathe­matics in Odessa, he studied for six years in Petrograd (now St. Petersburg), where Alexander Friedman was one of his mentors. Living in turbulent times, he kept on the move, and from 1928 took up residence in Göttingen and Copenhagen. His growing reputation in nuclear physics led to his election to the Acad­emy of Sciences of the USSR in 1931 at the age of twenty-­eight. From that time, he worked at a number of Soviet institutions, but found life increasingly intolerable ­under the oppression of Stalin’s regime. In 1933, he and his wife obtained permission to attend a major workshop in nuclear physics in Brussels—­t he Seventh Solvay Conference—­a nd ­t here staged a dramatic defection. They w ­ ere penniless by this stage, but George was intent on getting to Amer­i­ca. This they managed to do in June 1934. In Paris, Marie Curie, the most famous ­woman scientist in the world, supported

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them briefly, a­ fter which they spent a few months in E ­ ngland and Copenhagen. Neils Bohr and Ernest Rutherford advanced the cash for their tickets. (Both w ­ ere soon repaid.)6 Merle Tuve, who was sure that Gamow would become world-­famous, was instrumental in persuading GWU’s president to offer the émigré nuclear physicist a full professorship.7 George was now brimming with happiness, fun, and a passion for scientific discovery. The following year, his son, Igor, was born and by 1940 George was a naturalized American citizen. Gamow was an extraordinary character, a genius when it came to original ideas and intuition about the nature of the universe w ­ hether he turned his mind to the totality of creation or the minutiae of its subatomic workings. He was constantly posing intriguing questions that no one had dreamed of asking before. Despite this brilliance, he had a weakness: he was often not particularly good at the mathematical formulations and calculations needed to answer his own conundrums—or he d ­ idn’t have the patience. He was, however, ­adept at persuading ­others to grind through the detailed analyses. Ralph ­A lpher and Robert Herman ­were two of the many helpers that Gamow turned to in his search for answers (and Vera would l­ater be another). In 1946, Gamow was puzzling over how the dif­fer­ent chemical ele­ments that make up the world around us came into being. They must have been created in a place where it was hot and dense enough for subatomic particles to collide. That, he believed, was exactly the state of the w ­ hole of the universe immediately ­a fter it first burst into being and began to expand. Gamow dared to picture the infant universe as a cosmic crucible where m ­ atter was transformed from one ele­ment to another in accordance with the laws of nuclear physics. He sketched out some rough ideas on how the pro­cess of ele­ment building could have happened. Typically, Gamow had not fleshed out the details—­but then, his doctoral student, Ralph Alpher, was busily searching for a new thesis topic. Alpher agreed to take on this task. By 1948, he was ready to defend his thesis and a joint paper was in the pipeline.8 Gamow was renowned for his quirky, almost childlike sense of humor and penchant for playing with words. How curious that his name and that of his collaborator Alpher sounded so much like alpha and gamma, the first and third letters of the Greek alphabet. They only needed a collaborator called beta to complete the sequence. Musing on the joke, it occurred to him: Bethe! Without so much as asking, Gamow inserted the name of the dis-

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tinguished Cornell professor of physics Hans Bethe, as a coauthor “in absentia.”9 It was typical of Gamow’s eccentric be­hav­ior. Fortunately, Bethe saw the joke. He was even persuaded by Gamow to serve on the committee examining Alpher’s thesis. When Alpher subsequently teamed up with Robert Herman, Gamow lamented that Herman resolutely refused to change his name to Delter.10 Robert (Bob) Herman was a physicist with a PhD from Prince­ton University. He had joined Tuve’s group developing the proximity fuze in 1942 and first met Ralph Alpher at APL in 1944. A ­ fter the war, Herman and Alpher moved to the newly established APL Research Center, dedicated to fundamental academic research. Herman’s specialty was infrared spectroscopy, but during gradu­ate school he had taken a course in relativity and cosmology. No sooner had the “alpha-­beta-­gamma” paper been submitted than Alpher enlisted his friend Bob Herman to work with him. Together they set about improving the theory of the exploding universe. Before 1948 was out, they had arrived at the stunning conclusion that, even t­ oday, the universe must be full of radiation left over from moments ­after it began. They even calculated what the effective temperature t­ oday of the universe must be. All of this was completely ignored by most of the astronomical community, in which an enthusiasm for understanding the universe of galaxies had yet to ignite.11 Beavering away in the eve­nings from 1948 to 1955, Alpher and Herman together produced around ten papers on innovative ideas about the early universe and the origin of the chemical ele­ments. When Bob Rubin joined APL, their cosmological research was still in full swing. Rubin shared an office with Bob Herman, and Ralph Alpher was based just along the corridor. The two Bobs soon became close friends. Vera received her first telephone call from Gamow in the fall of 1951, when Bob had been working at APL for only about a month. Bob had spoken with Ralph Alpher about Vera and her master’s thesis on the rotation of the universe. Alpher had then told Gamow, who was intrigued and wanted the full story firsthand from Vera herself. So began a regular telephone dialogue between Vera and George. He was, he said, planning to mention her results at one of the colloquia that took place at the APL Research Center; most Fridays at 3:30 pm, staff gathered in a small lecture room to be regaled with an account of some recent scientific work.12 Vera did not get to hear what Gamow said about her findings on the rotation of the universe b­ ecause APL

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had an edict in place forbidding spouses from passing any farther than the lobby. Vera did not yet have a strong enough case to challenge that ruling. While her husband was spending his days in the com­pany of first-­rate scientists, ­doing what he loved, Vera was at home with Davy. They had taken an apartment in Hyattsville, just to the east of Silver Spring. ­Here, Vera felt isolated and sorely missed intellectual stimulation. Bob took the car to work most days and, in any case, she d ­ idn’t learn to drive u ­ ntil 1953. S­ he’d failed her driving test when they w ­ ere in Ithaca and a­ fter that Bob h ­ adn’t wanted her driving while she was pregnant. It ­didn’t take Vera long to realize she was not ­going to adapt to the life of a suburban ­house­wife, even temporarily. She was overwhelmed by unhappiness. She looked forward eagerly to the monthly delivery of The Astrophysical Journal: it was her lifeline, a tenuous connection with the world of astronomy from which she felt cut off. And yet, when it came, she wept, overpowered by emotion ­because it was a symbol of every­thing she missed so deeply. As much as she adored Davy, nothing had prepared her for this sense of isolation and being trapped in a daily domestic routine. Bob was sensitive to ­Vera’s predicament. Within weeks he recognized the prob­lem and knew the solution: Vera must go back to school as soon as pos­si­ble. They talked it over. It could only work if Pete and Rose agreed to play a key supporting role in any plan. But would they? Fear that Rose would think her a bad ­mother concerned Vera. But she need not have worried: Rose became one of her staunchest supporters. Vera’s first hurdle, however, was to identify a local university offering an astronomy PhD course. With her phobia of physics she was in no doubt that she needed to be in a dedicated astronomy department. Luckily, t­ here was one—at Georgetown University. Founded in 1792 by the Roman Catholic Jesuit order of scholarly priests, it was situated on a hilly campus in Washington’s Georgetown district. Perched on one of the hills, rising 150 feet (45 meters) above the Potomac River, was an observatory, home to the university’s small astronomy department. Five single-­story buildings of varying ­vintages clustered around the original observatory, a white-­painted brick building of two stories dating from 1844. This handsome main building, in the Greek revival style, was one of the oldest observatories in the United States. Since renovation in 1888 and the replacement of its first telescope by a new, much larger one in 1893, it had changed very ­little. That telescope, with its 12-­inch (30-­centimeter) object glass, still sat at roof level atop its mas-

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Fig. 4.1 Georgetown University Observatory in 2018. (Jacqueline Mitton)

sive brick pier as it had for sixty years. It was protected by an enclosure on the balustraded roof, capped by a rotating dome twenty feet (six meters) across.13,14 ­Father Francis Heyden, SJ, presided over the astronomy department. Dispatched ­there by the Jesuit order in 1946, he became director of the observatory in 1948. Ever since his arrival, he had been trying single-­handedly to expand both research and teaching as best he could on a shoestring bud­get. His first gradu­ate student had entered the observatory doors in 1946, and Vera was about to help swell the growing number of enrollments. Sometime very early in 1952, Vera paid a visit to ­Father Heyden, who had his fin­ger on the pulse of every­thing that went on in his department, including who it would take on for gradu­ate studies. Heyden was a short, somewhat stocky man in rimless spectacles. In his mid-­forties, he was already balding on top. His somber garb of black clerical shirt and suit belied his spirited personality and good humor. His office was just large enough for his old wooden desk, littered with papers, some filing cabinets, and a ­couple of chairs. A significant fraction of the floor was taken up by the sprawling hulk of the

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second occupant of the office: George, a 155-­pound (70-kg) ­Great Dane, whose carefree life ­Father Heyden often envied when he felt burdened by the demands of the job.15 The easygoing Jesuit was more than happy to accept a student with an academic rec­ord as good as Vera’s. It was his nature to be genuinely considerate ­toward students—or indeed anyone he met—­who had challenging circumstances to deal with. Courses Vera had passed at Vassar and Cornell fulfilled a number of the requirements for the PhD degree. If all went well, she could expect to earn a doctorate within only two years. She could sign up right away for the spring 1952 semester, beginning in February. Vera was ­going back to gradu­ate school and that was that. No m ­ atter that she was pregnant again and expecting her second baby in September. ­There was, however, the not insignificant ­matter of the fees. Vera’s tuition fees would be challenging for the young f­amily, so she turned to the American Association of University ­Women in the hope of being awarded a fellowship. Its committee members, however, ­were unmoved by her situation. In their estimation, ­there ­were more needy ­women, and they figured Vera would complete the course anyway, even without a fellowship. Of course they ­were right; nothing was ­going to stand in her way. Bob paid the fees from his salary. Vera’s first encounter with Gamow in person was in the spring of 1952, when she had just started at Georgetown. At his request, they met in the library of the Car­ne­gie Institution’s DTM. The DTM was, as it is now, on Broad Branch Road on the northeast side of the district. As she approached the site, Vera saw for the first time the low buildings, set well back from the road amidst ­gently undulating, grassy slopes dotted with trees. She entered the front door and made her way upstairs, through a corridor lined with books, then into the library with its dark wooden shelves. She was wearing a brown-­and-­white-­striped maternity dress on loan from Ralph Alpher’s wife, Louise. Gamow was already ­there, waiting for her. What happened next at the meeting was a blank in Vera’s memory when, forty years ­later, her recollections ­were recorded—­but the peaceful, leafy setting made a lasting impression. Shortly afterward, in late April, Vera was excited to receive an invitation from Gamow to attend a meeting at the National Acad­emy of Sciences as his guest. It was the first time she had been inside the august walls of this “­temple of science,” as President Calvin Coo­

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lidge had dubbed it at the dedication ceremony on April 28, 1924. Twenty-­ nine years hence, she would be elected to its membership. Vera was required to attend classes in the early eve­ning, for two hours twice a week. This timing accommodated the majority of the students, who ­were young gradu­ates already employed at one of the federal government’s scientific establishments in the Washington area, such as the National B ­ ureau of Standards (NBS), the Naval Research Laboratory (NRL) or the US Naval Observatory (USNO). Heyden also recruited part-­time lecturers from ­these centers of excellence, calling on their specialties to enrich what he and his small regular staff could offer. One of ­these individuals was John P. Hagen, who in the late 1950s went on to head Proj­ect Vanguard, Amer­i­ca’s fraught, early initiative to launch an Earth satellite into space. He had been on the staff of NRL between 1935 and 1955, and in 1949 was awarded Georgetown’s first astronomy PhD. Vera learned her radio astronomy from Hagen. She was solidly grounded in spectroscopy by another inspirational lecturer brought in by Heyden: Carl C. Kiess of the NBS. F ­ ather Heyden himself delivered lectures on stellar statistics and galactic structure.16 Getting Vera from Hyattsville to Georgetown for her eve­ning classes (ten miles, or sixteen kilo­meters, by car), while also ensuring that the c­ hildren ­were cared for, required an elaborate logistical plan. The movements and responsibilities of Bob, Rose, and Pete ­were coordinated and timed with near military precision in an amazing display of ­family solidarity. ­Here’s how it worked. ­Every Tuesday and Thursday at 5:00 pm, Bob left APL in Silver Spring and drove the two miles to where Vera’s parents lived in Washington. Th ­ ere, Rose got into the car, carry­ing with her a packed supper for herself and Pete. Meanwhile, back at Hyattsville, Vera was feeding the ­children, grabbing a bite for herself, and fixing a picnic supper for Bob. He arrived at Hyattsville with Rose at about 5:30 pm. In a hasty exchange of passengers, Bob deposited Rose, who was to take charge of the ­children, while Vera, carry­ing her husband’s supper, jumped into the car. Th ­ ere was just time for Bob to drive to Georgetown before Vera’s classes began at 6:00 pm. Pete in the meantime finished his workday, drove to Hyattsville to join Rose, shared the supper she had prepared, and stayed on hand to take her home l­ater. All the astronomy at Georgetown was taught in a classroom inside the observatory building. So, once Bob drew up in the observatory’s small

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Fig. 4.2 Vera Rubin’s parents, Pete and Rose Cooper (date unknown). (Rubin ­f amily)

parking lot, Vera tumbled out of the car and vanished inside. Now Bob had two hours to kill and could relax. First he ate his sandwich supper in the car, then he, too, went inside the observatory and settled down to work in its small library. Classes over, it was back to Hyattsville to relieve Rose and Pete. It must have seemed like a new twist on the old riddle about how to transport a fox, a chicken, and a bag of corn across a river in a rowboat. Vera was exhausted by every­thing she had to do, but exhilarated to be fully engaged with astronomy once more. She took the academic work in stride. Her official transcript rec­ords all A’s for her work in celestial mechanics and astronomical optics, and a B+ grade for “research” in her first semester. Now she needed to s­ ettle on a thesis topic. Carl Kiess, the spectroscopy lecturer from NBS, put a proposal to her. The origin of many of the faint features in the Sun’s spectrum remained mysterious. Since the observatory had the necessary equipment for making the observations, mea­sur­ing the wavelengths of the faint spectral lines and identifying them was a thesis proj­ect Vera could readily take on.

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Kiess had good reason to think Vera might be interested. She had become friends with one of the rare ­women astronomers in Washington, Charlotte Moore Sitterly, who worked on solar spectroscopy at the NBS. Vera greatly appreciated Charlotte’s friendliness and willingness to discuss astronomy with a young student, and when Charlotte encountered a practical prob­lem, Vera offered to help her with it. Mount Wilson Observatory in California had supplied photo­graphs of the solar spectrum recorded in superbly fine detail on huge glass plates. ­These plates captured impor­tant data, but they ­were too large for any of the NBS’s mea­sur­ing equipment. Georgetown University, however, had a machine that could accommodate them. H ­ ere was something Vera could do to repay Charlotte’s kindness and interest in her, so she took on the mea­sur­ing work as a f­ avor.17 When it came to her thesis, though, it was a dif­fer­ent m ­ atter. She briefly gave the solar spectroscopy a try, but it was not her idea of exciting astronomy. While she liked observing and photography, she had no interest whatsoever in that par­tic­u­lar scientific field. Galaxies w ­ ere what enticed her. Vera knew she had to come up with a totally dif­fer­ent topic—­and she had a good idea where she might find one. Th ­ ere was someone she had come to know who fizzed with novel thoughts, someone who was always posing questions that piqued her curiosity. That person was George Gamow, professor at George Washington University. At Georgetown, ­Father Heyden, in his usual relaxed way, was content for Vera to take m ­ atters into her own hands and he was willing to facilitate the formalities that would allow Vera to have an external thesis advisor. So she approached Gamow. They ­were acquainted and George clearly found her engaging. Now, just as she was looking for a thesis proj­ect, he needed an assistant to relieve him of some tedious mathe­matics. The analy­sis he wanted would be just the job for such an able gradu­ate student, especially one who could tap into expert advice from her husband and his APL colleagues. The question Gamow posed to Vera arose from a train of ideas he had been thinking about for several years, concerning how the universe was created and galaxies formed. How did the gas filling the universe soon a­ fter the big bang break up into clumps to form galaxies? Back in 1945, the first question Alpher had considered with Gamow was w ­ hether small irregularities in the density of the primordial gas could simply grow into clumps big enough to become galaxies by the action of gravity. He concluded that they c­ ouldn’t. Unfortunately for Alpher, a Rus­sian student named Evgeny

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Lifshitz was tackling the same prob­lem and got into print first—­with the same conclusions. Having been scooped, Alpher set to work on his second PhD topic, the one that led to the “alpha-­beta-­gamma” paper.18 For Gamow, though, the question of how galaxies could grow out of a sea of gas was unfinished business. Could he imagine any mechanism for creating galaxies? In February 1952 he speculated that the answer was “extensive turbulent motion” in the primordial gas, which he argued would cause clumping.19 Surveys of galaxies suggested they w ­ ere not scattered uniformly all over the sky; intuitively, he believed that the apparently irregular distribution of galaxies was to be expected if his hypothesis ­were correct. Gamow wondered ­whether galaxies cluster together over any par­tic­u­lar distance scale. Their average density over a large patch of sky is a s­ imple calculation. But what might one find by focusing in on smaller and smaller areas and comparing them? How would the density of galaxies seen in each ­little box differ between one place and another and from the average? Enter Vera. Her task would be to develop a mathematical method to make a formal statistical analy­sis of the distribution of galaxies. Relatively l­ ittle was known about clusters of galaxies at that time. A proper mathematical analy­sis of how galaxies w ­ ere distributed across the sky might throw light on how the primordial gas had swirled around soon ­after the big bang. Writing to Ralph Alpher on August 5, 1952, Gamow mentioned that he had suggested Vera to Martin Schwarzschild as “a pos­si­ble person to do Turbulence.”20 When Vera wrote to Schwarzschild on August 13, she told him she was expecting her second child in a few weeks, a­ fter which she would “start working on Prof Gamow’s prob­lem of turbulence in the distribution of the galaxies.” So within a week it was all settled. Schwarzschild wrote back to Vera a week ­a fter that: “Professor Gamow told me quite a lot about the work on turbulence in the universe and I sure must admit that you are sliding from one fascinating topic into the next.”21 No doubt, Schwarzschild had put in a good word for her with Gamow. Gamow himself seemed very pleased with the arrangement. Writing again to Alpher on August 29, he says with an air of self-­satisfaction, “How about Vera Rubin and cosmic turbulence?”22 Vera gave birth to a ­daughter, Judy, on September 15. Registration for the fall semester at Georgetown was eight days l­ater and the rules w ­ ere inflexible. Would-be students had no choice but to show up in person and stand

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in line to register. Vera’s f­ ather took her to the university where he stood in line while she sat to one side with Judy u ­ ntil her turn came.23 Being at gradu­ate school with two very young c­ hildren was tough. “It was the hardest ­thing in my life,” she told Mercury’s Sally Stephens in 1992. But she was “truly blessed” to have married the right man. Bob understood her ­because he was as dedicated to his physics as she was to her astronomy, and the two w ­ ere also equally committed to ­family life and raising ­children. In fact, ­there was no time for anything e­ lse. Papers w ­ ere scattered around the ­house, mixed in with the ­children’s toys. The life of the Rubin ­house­hold revolved entirely around the small world of their research and their ­children, no m ­ atter what was happening elsewhere.24 In the nation at large, the po­liti­cal atmosphere was tense. Amer­i­ca was feeling the chill of the Cold War between the West and the Soviet Union and, on the other side of the planet, trying to thwart the spread of communism. Thousands of American soldiers had been killed since the start of the bloody Korean War in 1950. At home, Senator Joseph McCarthy was whipping up anti-­communist paranoia. And in the 1952 presidential election, Republican Dwight Eisenhower’s landslide victory ended the Demo­ crat’s twenty-­year hold on the presidency. But none of this seemed to have any impact on Vera and Bob’s preoccupations. Vera met with George Gamow ­every four to six weeks, e­ ither in the DTM library or at his home in Chevy Chase. The meetings w ­ ere mostly congenial, although on a few embarrassing occasions she was witness to a shouting match in Rus­sian between George and his first wife Rho, whose marriage was breaking up. Vera and George would converse about the work each of them had been d ­ oing. Gamow d ­ idn’t advise or direct her in any supervisory way, but he was generous t­ oward her. She felt, however, that she never r­ eally got to know him, and for guidance on the mathe­matics she had to look elsewhere. The complex mathematical prob­lem Vera had taken on was somewhat challenging for her. Bob, as always, was her chief mentor and sounding board: they had long discussions, figuring out how to tackle the statistical analy­sis. It was François Frenkiel, however, a hydrodynamics specialist at APL, who supervised her detailed mathematical work most closely. And a smiling Vera could breeze past the gatekeepers at APL a­ fter Frenkiel secured permission for her to go to his office.

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The only suitable counts of galaxies available to Vera ­were the ones made at Harvard ­under Harlow Shapley which had been published some fifteen years ­earlier. ­Because t­ hese counts covered only small, selected areas of sky, Vera would have to ensure her method could cope with that. Once she had devised her mathematical formulas and had assembled the data in a usable form, the job became one gigantic number-­crunching exercise—­something that ­today would be done in a jiffy on a computer. In 1953, though, it meant sitting for hours in front of an electric calculating machine, clattering through mountains of arithmetic. By this stage, Vera was leading a double life and burning the candle at both ends. During the day she was effectively a full-­time ­mother and homemaker. She took the ­children out to the playground and cooked the ­family meals. Only when Davy and Judy had an after­noon nap could she snatch a daytime hour or two to work at her astronomy. Once the c­ hildren ­were in bed at around seven, however, she switched roles and her night shift as a researcher began in earnest. It would often be two in the morning when she fi­nally collapsed, exhausted, into bed. Through the fall of 1952 and spring of 1953, Vera continued to attend lectures twice a week and to work on her thesis at home. Despite her long days and late hours, she achieved high grades in both semesters: A for research, A-­for solar physics, and B+ for astrophysics. At one of their regular meetings, Gamow informed Vera about a forthcoming four-­week symposium on astrophysics taking place at the University of Michigan in the summer. He would be one of the guest speakers. Gradu­ate students ­were invited, and grants would be available to help some students with the costs of attending. He thought Vera might like to go. This idea greatly excited Vera. It would be her first real chance to engage with leading astronomers, as well as students of her own age and postdocs just embarking on their c­ areers. She had to be t­ here! What she could not possibly have anticipated on hearing Gamow’s suggestion was how significant a turning point the meeting would be for astrophysics, or the enduring influence it would have on most of the young astronomers who gathered in Ann Arbor. The Michigan symposium was the brainchild of Leo Goldberg, the dynamic young director of the University of Michigan’s observatory. He had taken up the directorship in 1946, aged only thirty-­three years, determined to revitalize astronomy now that scientists w ­ ere no longer being diverted into war work. He was destined for a long and distinguished ­career as an out-

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standing leader in the world of astronomy.25 While a student at Harvard in the 1930s, Goldberg had participated in memorable summer schools or­ga­ nized by Harlow Shapley. Th ­ ese gatherings each summer between 1935 and 1942 had attracted a host of leading astronomers from all over the world. ­There was one eminent astronomer, however, who Goldberg had hoped might feature at a Harvard summer school but never did: Walter Baade, a German national who had quit Hamburg in 1931 to take a staff position at Mount Wilson Observatory in California, where he worked in observational cosmology. Ever since arriving at Michigan, Goldberg had harbored the ambition to stage an event that would attract Baade.26 The year 1953 was a particularly opportune time and Goldberg was determined to seize the moment. At the General Assembly of the International Astronomical Union in Rome the previous summer, Baade had stunned the world by declaring the known universe to be twice as big as had previously been thought. This dramatic announcement was the culmination of a series of discoveries Baade made as a result of photographing the sky over a number of years. As a German, he had not been entrusted with war work, but he was permitted to continue his astronomical research. With the Mount Wilson 100-­inch telescope virtually to himself, and the streetlights of nearby Los Angeles dimmed b­ ecause of the war, he took advantage of unusually dark skies to push his outstanding skills as an astrophotographer to the limit. In the fall of 1943, Baade turned his attention to the ­great Andromeda Galaxy, in which he pinpointed individual stars in the galaxy’s crowded ­central region for the first time. Baade’s singular achievement required an im­mense level of skill and dedication. He realized that ­these mainly reddish stars are altogether less luminous than the bluer stars marking out the ­galaxy’s spiral arms. The dimmer and redder stars concentrated around the nucleus of the galaxy also had much in common with the tight swarms of stars in the Milky Way known as globular clusters, and the dwarf elliptical galaxies close by the Andromeda Galaxy. It was as if the Andromeda Galaxy—­a nd indeed the Milky Way, too—­were made up of two distinct populations: brighter, bluer stars, which he called Population I, and dimmer, redder stars constituting Population II. ­These discoveries w ­ ere of such profound significance that The Astrophysical Journal took the unpre­ce­dented step of publishing photographic reproductions of the highest quality with Baade’s paper. It took two assistants most

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of the summer to make seven hundred prints by hand. The paper caused excitement among astronomers when it was published in 1944, especially as it emerged that age was the discriminator between Baade’s two populations. Population I stars are the youngsters, while Population II stars are the se­ nior citizens.27,28 Vera was familiar with Baade’s discovery b­ ecause she had attended a talk about it given by Philip Morrison when she was a student at Cornell. The existence of two distinct stellar populations of dif­fer­ent ages set theorists thinking more seriously than ever about what happens to stars as they age and evolve. What transformations does the nuclear furnace deep inside a stellar core undergo, and how do t­ hese affect a star’s appearance? But something even more breathtaking was to come. Baade realized that t­ here was a prob­lem with the method astronomers ­were using to mea­sure distances to nearby galaxies. That method involved three classes of variable stars, whose brightness r­ ose and fell in a predictable, regular manner over periods ranging from a few hours to a few weeks. Henrietta Swan Leavitt had discovered in 1908 that the longer such a star takes to go through its cycle of change, the more naturally luminous it is on average. It follows that timing a star’s cycle of variability unlocks its distance. Baade found, however, that one of the three classes of variables being employed as standard light sources in distance determinations belonged to his Population I, while the o­ thers ­were members of Population II. Astronomers had been mistaken in assuming that the three types of variables used for mea­sur­ing the distances to galaxies w ­ ere so closely connected that they could all be calibrated in the same way. Baade’s suspicions ­were raised while he was searching for the dif­fer­ent classes of variable stars in several galaxies and star clusters. The observations c­ ouldn’t be squared with that assumption. But every­thing slotted into place if the Population I variables that had been observed in nearby galaxies, such as the Andromeda Galaxy, w ­ ere more luminous than previously supposed. When researchers gained access to the new 200-­inch telescope at Palomar Mountain for the first time in 1950, he was able to prove his point. The amazing consequence was that the observable universe was double the size astronomers had taken it to be.29 Although the audience was spellbound when Baade announced this dramatic news at the Rome IAU meeting in 1952, it was several years before he got around to publishing his own account of his research. Despite his reputation and legendary status, Baade rarely committed any of his findings to

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print. Instead, his research was mostly shared with colleagues by word of mouth in informal gatherings. He was always a draw and astronomers flocked to hear him. Securing Baade’s presence at Michigan was sure to be a coup for Goldberg. As a young researcher, he had spent time with Baade at Mount Wilson in 1940 and admired him greatly. Baade readily warmed to Goldberg’s suggestion of a summer school at which he would be the star. Jointly they de­cided whom to invite as the main supporting acts. For one, Baade suggested Edwin Salpeter, a twenty-­eight-­year-­old nuclear physicist of exceptional ability working with Hans Bethe at Cornell University. Salpeter had just turned his attention to nuclear pro­cesses inside stars: he had apparently made a breakthrough by showing how helium nuclei in g­ iant stars could combine to make carbon. Baade also proposed George Batchelor, an Australian applied mathematician, by then at Cambridge, E ­ ngland, who was in his early thirties and a renowned expert in the theory of turbulence. The other principal speaker was to be George Gamow, guaranteed to entertain and stimulate discussion. The event was scheduled for four weeks, from June 29 to July 24. Goldberg persuaded the National Science Foundation to support his venture with a grant of $5,500. As well as paying the speakers’ expenses he would to be able to fund “at least one gradu­ate student from each of the leading gradu­ate schools in astronomy.” ­There was enough money in the pot to offer grants to fourteen students and postdoctoral fellows. Vera applied for one of ­these, but despite being Gamow’s student she was turned down. No reason was given for the negative outcome, but perhaps it was b­ ecause Georgetown ­didn’t rank as one of the leading gradu­ate schools in astronomy. The chair of the Physics Department at Michigan, Ernest Barker, wrote her an apol­o­ getic letter: “I sincerely hope that you ­will find it pos­si­ble to attend the symposium even though we cannot provide you with financial assistance.” Leo Goldberg sent her the details of the program and confirmed that t­ here w ­ ere no fees and no admission procedure.30 Initially Vera was disappointed, but then admitted that she had not thought through how she would cope with being away for a month when she had ­children aged two-­and-­a-­half years and ten months. Once again, Rose and Pete rescued the situation. They offered to care for the c­ hildren for two weeks, allowing Vera and Bob to make the trip to Ann Arbor. In Michigan’s sticky summer heat, they took up temporary residence in a rented room for the second half of the symposium.

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Vera’s interest in galaxies was reinforced by the revered Baade’s gripping lectures. He covered the classification of galaxies by shape, the dif­fer­ent populations of stars, and the evolution of stars and galaxies. He argued that the gas and dust clouds in the arms of spiral galaxies are cosmic breeding grounds where new stars continually form. Baade’s biographer, Donald Osterbrock, who was at the symposium as a young postdoctoral researcher, described them as “the most productive series of lectures” Baade ever gave.31,32 Having joined halfway through the symposium, Vera had missed Gamow’s six pre­sen­ta­tions, which had covered the age and expansion of the universe, general relativity, the origin of the chemical ele­ments, the formation of stars and galaxies, and stellar evolution. With his unique, colorful style, he had almost succeeded in upstaging Baade. He was still on the scene, however, continuing to interact with the participants and inevitably drawing attention to himself. He drank heavi­ly, fell asleep during lectures, and asked seemingly stupid questions. Vera was embarrassed by his be­hav­ior even as she had to concede that he was a brilliant scientist; his intuition exceeded that of anyone she ever knew and his grasp of new ideas was always far ahead of every­one ­else’s.33 She was thrilled, if a ­little ner­vous, when Gamow arranged for her to meet with him and Baade. The men at the summer school, including Baade, w ­ ere mostly staying in a fraternity h ­ ouse on the campus. It was h ­ ere that much of the networking and intense discussions happened. Osterbrock observed that Baade “thrived in the atmosphere, talking and discussing astronomy almost constantly, drinking too much coffee, smoking too many cigarettes and getting too ­little sleep, but it was wonderful for the attendees.”34 In this heady environment, Vera found herself ensconced for many hours with Baade and Gamow, two of the most famous astronomers in the world, perched “on the edge of someone’s bed,” while asking and answering “very tough questions.”35 For Vera, the w ­ hole two weeks was “­really g­ reat” and “a magnificent learning experience.” At Michigan she met for the first time many astronomers who would ­later be close friends and colleagues, including Margaret and Geoffrey Burbidge, with whom she would spend a productive year in California a de­cade ­later, Nancy Roman, and Nancy Boggess. For all the fifty or so participants, especially t­ hose just starting out in their c­ areers, it was also a historic meeting. Some forty years a­ fter the event, Owen Gingerich, one of the attendees who received financial help, and who was l­ater a good friend of Vera’s, col-

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lected reminiscences of that landmark month in the history of astrophysics. Allan Sandage, one of the world’s leading observational cosmologists, looked back on 1953 nostalgically and told Gingerich, “It was a heady time b­ ecause all of the connections between the vari­ous branches of stellar astronomy ­were laid out in a scene before our eyes, simply waiting to be embraced by the ideas of [stellar] evolution.” Edwin Salpeter reflected, “No other meeting I have ever gone to has had more of a shaping influence on my academic ­career.”36 Gingerich himself, with the perspective of a distinguished historian of astronomy, summed up what made Michigan so memorable: “In 1953 . . . ​ the astronomical fraternity was actually quite small. Thus a symposium with 50 in attendance represented a comparatively large impact on the astronomical community. Furthermore, astronomy was just regaining the momentum lost during the years of World War II. . . . ​This configuration of circumstances made the Michigan summer school a unique, unrepeatable experience. . . . ​ For some of us, who w ­ ere just in the initial stages of professionalization, a metamorphosis that takes place in gradu­ate school, the 1953 Michigan Symposium on Astrophysics was a wonderfully formative experience. . . . ​The symposium helped to link together an entire post–­World War II generation of American astronomers.”37 Vera was undoubtedly one of ­those participants for whom the experience was formative. It was a small but impor­tant step along the way to becoming a professional astronomer. In the fall semester back at Georgetown, Vera worked on completing her thesis and taught herself sufficient German to get through the compulsory German language test. On December 18, she passed her PhD examination with honors. Meanwhile, Gamow had abandoned wintery Washington for six months of sabbatical leave at balmy Berkeley in California. Vera remained on the books of Georgetown University, registered as a “continuation student” u ­ ntil she could formally receive her PhD at the commencement in June. Th ­ ere was something impor­tant that yet had to be done—­getting into print her thesis on the fluctuations in the distribution of galaxies. Vera and Gamow corresponded about publication and their ideas differed. George had a related paper of his own in press, in which he was citing Vera’s work.38 It was due to be published in the Proceedings of the National Acad­emy of Sciences and he thought Vera should submit her thesis to the same journal. Vera, however, wanted to see her name in the prestigious Astrophysical

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Journal, which she regularly read from cover to cover. She knew that George did not get on at all well with the editor of The Astrophysical Journal, Subrahmanyan Chandrasekhar (universally known as Chandra), and suspected this was the reason Gamow was steering her away from Chandra’s journal. She felt, however, that she had nothing to lose by trying The Astrophysical Journal first. At Vera’s request, George looked over her manuscript and posted it back to her. “It was quite nice,” he said in his reply to her, though confessing, “I could not force myself to plunge into the details of e­ ither integral-­taking or plate-­arranging, but I presume it is all right.” He did, however, ask a colleague at Berkeley, Elizabeth Scott, a specialist in statistical methods, to look over it. George forwarded to Vera what he described as Miss Scott’s “remarks” without any comments of his own.39 Miss Scott, it turned out, was not entirely impressed. She raised numerous technical issues and compared what Vera had done unfavorably with similar work by a student of Chandra’s, D. Nelson Limber. Back in January 1953, just a few months a­ fter Vera had agreed on her thesis topic with Gamow, The Astrophysical Journal had published a paper by Limber.40 He had been tackling the mathe­matics of how to describe the distribution of galaxies in terms of fluctuations from an average density well before Vera got started. Limber’s method, however, was designed for data covering large swaths of sky. He had been granted access to a new, more comprehensive galaxy survey from the Lick Observatory. This data was unpublished and not available to Vera. Nevertheless, Vera had not been deterred. Limber had only published his equations and had yet to produce any analy­sis of galaxy data. Furthermore, her method would take account of her sparser data. Predictably, Chandra rejected Vera’s paper. He admonished her for not addressing a multitude of “statistical pitfalls.” Limber had treated the same subject extensively, he said, and he enclosed a proof copy of the second installment of Limber’s paper, soon to appear in The Astrophysical Journal.41 It contained his student’s analy­sis of the superior, more extensive data. Vera sent her manuscript back to George, with a note added at the end: “The author is indebted to Dr. Chandrasekhar for a copy of a paper by Limber to be published in the May 1954, Astrophysical Journal, in which the data of Shane are analyzed in terms of a fluctuating density field. Limber’s results, while more complete than t­ hose obtained ­here, indicate values of the same

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order of magnitude as the above.” On May 3, Gamow replied smugly, “I have told you so! One should not deal with Chandra, at least in the fields in which he has the last say.” And so they moved on to Plan B: the very same day, Gamow dispatched the paper to the National Acad­emy of Sciences. A pithy postcard from George landed in Vera’s mailbox shortly afterward: “I have just written to Chandra that I have de­cided to have your m.s. published along with mine in P.N.A.Sc. Let him be mad. Please send a complete copy of m.s. to Shapley.” 42 Vera promptly fulfilled Gamow’s request and on July 12 Shapley replied with a kind and encouraging letter. It was not without criticisms, but he soothingly reassured Vera that she had “accomplished a very in­ter­est­ing analy­sis.” The letter ended on a gratifying note: “From the amount I have written, you and Prof. Gamow w ­ ill perceive how deeply your paper has interested me.” Three days ­after Shapley’s letter, Vera’s thesis work appeared in print.43,44 Although it had helped Vera earn her doctorate, it did not make any impact in the long term. The “turbulent universe” idea promoted by Gamow failed to catch on. It was resurrected by other theorists in the 1960s and 1970s, but eventually rejected as a nonviable theory.45 For Vera, completing her doctorate had been hard work, but it was something she felt driven to do and expected of herself. Her achievement while raising a young ­family and still only twenty-­five years old was truly exceptional in the early 1950s, and in the estimation of the Washington Post even newsworthy. The newspaper’s staff, it seems, had not forgotten the storm of controversy raised by Vera’s pre­sen­ta­tion at the Haverford AAS meeting in late 1950. And since then, Vera had occasionally contributed a letter to the editor. One printed on February 5, 1954, for instance, shows the gentle irony characteristic of many letters throughout her life. Harking back to her childhood fascination with number puzzles, she wrote: ­ fter struggling with the speed of light and attendant prob­lems, I now need A help with a prob­lem of my own. With my current bill from the Washington Suburban Sanitary Commission I find enclosed a reminder that leaking faucets can waste a lot of ­water. A faucet that leaks one drop a second, says the Commission, ­will cost me 192 gallons of ­water of month. But a faucet which leaks two drops per second ­will waste 429 gallons per month. And this news has, of course, kept me awake nights trying to figure out why 2 times 192 comes out to be 429. Do you know? Or perhaps one of your readers can explain it.” 46

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The editors sought the assistance of the Sanitary Commission’s public relations person to relieve Vera’s insomnia. “­There’s a very s­ imple explanation,” came the reply. “When the frequency of the drip is increased, the size of each drop of ­water is also increased.” Ah—no more sleepless nights. In May, with commencement a c­ ouple of weeks away, the Post sent a reporter to interview Vera at home, where the walls, he noted, w ­ ere adorned with pictures of the Horse­head Nebula in Orion and the galaxy M51. “A very understanding husband” had enabled her to attend classes at Georgetown two nights a week and do research in the library at weekends,” Vera explained. But now that she had her doctorate and was “even with her husband degreewise,” as the newspaper put it, she was planning to “take a vacation from study.” She hoped eventually to do research in astronomy, but “that ­will come ­after the c­ hildren are in school.” That was as far as her publicly stated ambition went.47 Privately, knowing herself as well as she did, she was almost certainly thinking other­wise. For the pre­sent, she was occupying herself with activities unrelated to astronomy, but close to her heart. She had become active on the committee of the Vassar Club, helping to select a student to receive the scholarship that had enabled her to go to Vassar a de­c ade ­earlier. And in an early sign of ­Vera’s enthusiasm for empowering w ­ omen, she had joined the League of ­Women Voters. The League was founded in 1920 when w ­ omen in Amer­i­ca first won the right to vote. Always a nonpartisan organ­ization, its aim was to encourage ­women to take an active role in civic affairs. One of its campaigns in the 1950s was, as it still is t­oday, to fight for voting rights for residents of the District of Columbia. From its first foundation as the federal capital in 1790, the administration of the district came u ­ nder the direct control of Congress and, b­ ecause it was not a state, its residents had no repre­sen­ta­tion in Congress or the Senate. The district still has no Senator, although, since 1971, it has been represented in Congress by a delegate who is only permitted to vote in committees. For nearly a c­ entury, from 1874 to 1973, local m ­ atters w ­ ere run by a three-­member Board of Commissioners rather than by an elected mayor and council. U ­ ntil 1961, DC residents could not even vote in presidential elections. Six times between 1948 and 1966, bills ­were introduced in Congress to give the district some degree of “home rule” but none of ­these ever passed into law. Vera joined a movement to collect signatures on a petition asking for a home-­rule amendment to be put on the ballot papers in

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one of the counties neighboring the district.48 It was a way of drawing attention to what she and many other p ­ eople saw as a burning injustice. In the event, it took another twenty years for the district to get its own mayor and elected council, albeit still with a Congressional veto. On June 7, Bob took young Davy and Judy to watch as their m ­ other was awarded her PhD. She had fi­nally finished gradu­ate school, but what next? Was she ­really ­going to retreat again into suburban motherhood, with nothing to challenge her intellect and only the vague hope of returning to astronomy in the f­ uture? Of course she ­wasn’t.

CHAPTER 5

A PROFESSIONAL ASTRONOMER AT LAST

I

n the summer of 1954, Vera found herself, for the second time, fresh from demanding studies with a crisp new diploma but no job. It was not clear where her scientific ­career was heading in the immediate ­future, but t­ hings now ­were dif­fer­ent than they had been four years ­earlier. She was gaining self-­confidence. She had been able to hold her own in disputation with such luminaries as Baade and Gamow. And she had befriended other w ­ omen who ­were already employed as astronomers: Charlotte Moore-­Sitterly, Margaret Burbidge, Nancy Roman, and Nancy Boggess.1 ­There was no reason she could not follow their example in due course. She was still only twenty-­six. Home life was happy. She and Bob wanted to raise a large f­amily and they had already been blessed with a boy and a girl. Vera was certain about the order of her priorities: her f­ amily was top of the list. She w ­ asn’t about to let the flame of her lifelong passion for astronomy be extinguished, however. To keep it burning, if only feebly, it must be fueled. She needed scientific challenges of some kind to keep up her spirits and exercise her mind. Vera joined the American Astronomical Society, and ­every two months she pored over the latest issue of The Astrophysical Journal. With all the formal requirements for a doctorate u ­ nder her b­ elt, she had time in 1954 to return to her interest in galaxies, and in par­tic­u­lar, the Milky Way system. Sometime during 1954, quite likely before she fi­nally finished as a student, she identified a modest line of enquiry she could follow up armed with her knowledge of Oort’s theory of the Galaxy’s rotation. She only needed published data and she could draw on her familiarity with Oort’s work from her master’s thesis. In the previous three years, t­ here had been a breakthrough in understanding the spiral structure of the Milky Way galaxy, opening the door to new ave­nues of research. Ten years ­earlier (as mentioned in Chapter 4), Baade had contrasted the distribution in space of young Population I stars with

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their older Population II cousins. This led astronomers who ­were hunting for hard evidence of spiral arms in the Milky Way to realize that the most vigorous, youthful stars of Population I, and the glowing gas clouds where they typically reside, would be like beacons strung out along our Galaxy’s spiral arms. William Morgan of Yerkes Observatory and his students Stewart Sharpless and Donald Osterbrock tested the idea with a program of observations. They created a sensation when, at the December 1951 meeting of the American Astronomical Society in Cleveland, Ohio, they traced out two spiral arms and tentatively pointed to a third.2,3 A dif­fer­ent discovery rapidly took the lead, however, in the race to map the Galaxy’s spiral arms. In the same year, in the department of physics at Harvard, a doctoral student, Harold Ewen, and radio engineer Edward Purcell had detected for the first time a characteristic signal at a wavelength of 21 centimeters coming from invisible clouds of interstellar hydrogen.4 The intensity of the radio signal, and how it varied across the sky, could potentially reveal the density of the clouds at dif­fer­ent distances and the way in which the clouds ­were moving through space. According to Baade’s work, ­these clouds, like the brilliant young stars, ­were marking out the galactic spiral arms.5 In the Netherlands, Jan Oort led one of the teams working intently from 1952 onward to gather 21-­centimeter radio observations. Equipment was not easy to come by in the early 1950s, but they pressed into ser­vice an old German radar dish known as a ­giant Würzburg antenna. As soon as they had enough observational material, Oort eagerly started to assess what the results revealed about the rotation of the Galaxy. To begin with, he assumed that every­thing in the Galaxy travels along circular orbits around the center, but he also pointed out where the data showed “deviating motions.” By July 1953 Oort and his colleagues could pinpoint lanes where the hydrogen was concentrated, and they identified them as parts of “spiral” arms. The Sun was located in one of the lanes, which he called the Orion arm.6 ­These developments in radio astronomy w ­ ere directly relevant to understanding our Galaxy, so Vera was deeply interested in them. In April 1953, while a student, she had written a piece entitled “Radio-­Frequency Galactic Radiation.” In it she referred to Oort’s work and observed that “accurate observations of the 21-cm radiation w ­ ill lead to impor­tant conclusions regarding the spiral structure of the Galaxy, the distribution of mass and of velocity, the presence of neutral hydrogen and its temperature.”7

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Vera took as her starting point the Dutch team’s observations of the 21-­centimeter radio emission but then challenged Oort’s assumption of regular, circular motion. She posed a question: “What are the consequences of assuming that each hydrogen cloud in the spiral arms has a streaming motion along the arm, in addition to its orbital motion around the center of the Galaxy?” Her remarkable conclusion was that, in such a scenario, many of the clouds would be nearer to the center of the Galaxy than the s­ imple theory predicted, and the longest arm found by Oort would actually be spiraling in t­ oward the galactic center. Vera submitted her paper to the AAS for pre­sen­ta­tion at the meeting to be held in April 1955 in Prince­ton, New Jersey. This would be her first meeting since December 1950, when she had attended the one in Haverford, and she was hoping for a stimulating encounter with the professional community. The AAS accepted her paper, but all we know about her experience of the meeting is that she again encountered Baade, who was “very nice, and very generous, and very, very welcoming.”8 It was her first paper on the structure and dynamics of the Galaxy, although only the abstract ever appeared in print.9 Vera was not being paid to do this research, however, and any cash she could earn was a welcome contribution to the ­family finances. Being realistic, she set her immediate employment objective no higher than working part-­time in her locality. In September 1954, Vera accepted a part-­time position as an instructor at Montgomery Ju­nior College in nearby Takoma Park. On Mondays, Wednesdays, and Fridays she made the fifteen-­minute car journey from her home in Hyattsville for sessions starting at midday. First, ­there was a one-­hour class in mathe­matics to give, followed by physics for two hours on Mondays and Wednesdays and one hour on Fridays. For her eight hours a week, she earned a total of $1,000 per semester—­roughly equivalent to $10,000 in 2020.10 Vera was the only physics instructor at the college, and she had a f­ ree hand to direct the courses as she saw fit. She continued into a second semester but then her teaching ­career was abruptly cut short. In the spring of 1955, ­Father Heyden realized he had a prob­lem—­and Vera, he figured, could be the solution. Ambitious to expand the activities of his department at Georgetown, he had taken on onerous contracts with the Air Force Cambridge Research Laboratories. The military chiefs naturally expected him to deliver answers without delay and t­here was a growing mountain of solar eclipse observations awaiting precision analy­sis. He had the funds to hire a part-­time re-

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search assistant and he offered the position to Vera. Solar eclipse observations did not particularly interest her but any job in astronomy was good enough to entice her away from teaching. She was back at Georgetown in April, making a start on her new job for a few hours a week while working out her teaching contract for the current semester. For the very first time, she was professionally employed as an astronomer. Even though the work was routine and unexciting, it was another step forward. The dean of Montgomery Ju­nior College, Donald E. Deyo, complimented Vera in his cordial acknowl­edgment of her resignation letter: “I should tell you that your work h ­ ere has been eminently satisfactory and that you have taken your place on our staff with graciousness and a high sense of professional responsibility.”11 Despite this praise, Vera would go on to omit any mention of her brief teaching ­career in her vari­ous CVs, and ­there is no rec­ord that she ever referred to it publicly when talking about her life. Did being a college instructor fit uncomfortably with her ­later self-­image? Did she dismiss the eight hours a week for two semesters as being insignificant and irrelevant? Or did she forget about it? We simply d ­ on’t know. Georgetown Observatory had a history of solar eclipse observing g­ oing back to the 1930s. A photo­graph taken in Maine during the 1932 solar eclipse by a team u ­ nder its director, F ­ ather Paul McNally, had won a Silver Award at the Chicago World’s Fair. Spurred on by that success, McNally had mounted eclipse-­chasing expeditions to ever more exotic locations, with support from the National Geographic Society. In 1936 he was in Siberia, the following year Canton Island in the South Pacific. By the time he arrived in Brazil in 1940, he was attempting to secure more accurate times for vari­ous critical stages in the pro­gress of the eclipse. Such precision observations could potentially refine the current state of knowledge about the orbits of the Earth and Moon and the size and shape of Earth’s globe.12 Then came the disruption of the war and a change of director, but in 1948 Francis Heyden successfully resurrected Georgetown’s association with eclipses. The observatory participated in an expedition to China, again supported by the National Geographic Society. Around this time, both the Army and the Air Force ­were becoming concerned about shortcomings in what was known about Earth’s size and shape ­because incorrect data could have disastrous consequences when targeting intercontinental ballistic missiles. ­There ­were not yet any artificial Earth satellites and, in theory, eclipse timings could provide the necessary improvement in precision.

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In February 1952, a total solar eclipse cut a swath across Africa. Heyden masterminded the observations at several dif­fer­ent sites along the track u ­ nder a contract with the Air Force Cambridge Research Laboratories. His aim was to test the feasibility of mea­sur­ing the Earth’s dimensions along a huge arc spanning the African continent from west to east. In 1955, Heyden was still trying to mine the data from the eclipse to extract even more exact answers. Meanwhile, the Air Force had paid for yet more observations of eclipses to be made in 1954 and 1955.13 As the data piled up, Heyden came ­under pressure to deliver results. Vera’s task was to develop a mathematical method for interpreting the Georgetown eclipse observations more accurately, and then to apply the method to the haul of data from the 1952 eclipse.14 Vera had barely started on the proj­ect when she announced to Heyden that she and Bob would be leaving Washington. Bob had de­cided to quit his job at APL and to take up a position as visiting assistant professor of physical chemistry at the University of Illinois in Urbana-­Champaign. They ­were also expecting the third addition to their f­ amily. (Karl was born in January 1956.) ­Father Heyden, flexible as always, saw no reason why Vera could not take her work for Georgetown with her to Illinois and do it from home. ­A fter all, the only equipment she required was a desktop mechanical calculating machine. Vera knuckled down to her task, which she knew would take many months to complete. The eclipse observers had recorded with photocells how the overall amount of light coming from the Sun changed over the course of the eclipse. It diminished as the encroaching Moon hid more and more of the Sun, then it plateaued during totality, and ­rose again from the end of totality ­until the eclipse was over. First Vera had to work out the mathematical relationships connecting the timed rec­ords with the relative positions in space predicted for the Sun, Earth, and Moon. ­These equations w ­ ere her tools for transforming the data acquired at the vari­ous African observing ­stations into useful answers. The second stage was churning through the calculations. Francis Heyden and Vera kept in contact by letter. In the fall of 1956 she complained about the late arrival of her paychecks. Heyden’s reply of November 18 pointed the fin­ger at the “new boy” hired to deliver the campus mail, whom he accused of ­going around “dripping envelopes from ­under his arm.” In the same letter he aired his hopes and fears about the f­ uture of the

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Air Force contract. It was due to be renewed on January 1, but a final report still had to be delivered on the work done u ­ nder the old contract. Could Vera produce a separate technical paper about some of the mathematical analy­sis she had done? He also made it known to her that he was pinning hopes on her l­abors being fruitful.15 “I do hope that your results for Africa w ­ ill be good, for a lot depends on them,” he confided anxiously. “I have been receiving some complaints b­ ecause so far we have not given any definite answers from our past observations, and the brass on top of the Air Force are only interested in the answers. If the observations of 1952 are accurate, we ­shall have a line across the continent which is very much desired ­because the data from the seventy-­five-­year survey from the bottom of Africa to the tip of Scandinavia is now finished. Our data combined with the arc of the 30th meridian w ­ ill be priceless for getting a new spheroid.” The Air Force was not his only worry. A victim of his own success, Heyden was now heading up a busy teaching department with an ever-­increasing intake of students. “This is a terrible year for me b­ ecause of the number of students,” he moans, unburdening himself on paper. “­There are one hundred and thirty undergraduates along with some five new gradu­ates. I find that I am starting the year with about twenty contact hours. When you do not hear from me immediately you w ­ ill know that I am g­ oing round in circles.” But ­Father Heyden had no intention of backing away from his plans for aggrandizement. “We ­shall soon have twelve ­people working ­here full time. Now ­there is another hair-­raising thought. This quiet ole place is becoming a tower of babel. Ah, for the life of George! But I like it better than playing around all by myself and I have some ideas for making it bigger.” In early December, Vera received another anxious letter from Heyden: the Air Force ­people ­were breathing down his neck. Was Vera’s report ready? She duly delivered it, and ­Father Heyden wrote to thank her on January 7. He also conveyed the news that with the new contract had come a bud­get cut, “but I have managed to keep you down for half time at $2.50 per hour.”16 Meanwhile, Bob was getting restless at the University of Illinois and was once again in search of new pastures. On April 23, Heyden wrote to Vera: “I wish that Bob could take a job teaching physics at Georgetown; then you would be near home, near us and every­thing would be swell.” It was a dream scenario that would not be realized—at least not exactly. Like Heyden, Bob

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felt oppressed by the amount of teaching he had to do, which left him too ­little time for the research he loved. His ideal job was pure research, and it did not take him long to find a position that suited not only him but Vera—­and as luck would have it, ­Father Heyden as well. In September 1957 the Rubin ­family returned to Washington, where Bob had been hired by the National Bureau of Standards.17 It was time for Vera to take stock of her situation, too. The eclipse proj­ect had worked out reasonably well for her. She could do it at home, which suited her perfectly while she did not have her parents nearby to help with child care. Now, however, she was returning to Washington and the task she had been set initially was close to completion. Two of her three reports ­were delivered and the remaining one would be done by fall. Might she not be able to find something dif­fer­ent to widen her astronomical experience? In any case, the Air Force funding was by no means secure. With Bob’s move settled by June, Vera de­cided to make some enquiries of her own, starting with a letter to Carl Kiess, the spectroscopist at the Bureau of Standards whose suggestion of a PhD thesis topic she had rejected in short order. She agonized over the wording. He knew her quite well and she felt able to be open with him but, on reflection, she scribbled through some of the more personal details in the first draft of the letter. She needed to sound more professional and businesslike, while wanting him to be in no doubt about her motivation.18 “I am certain,” she wrote, “that I do not have to confirm to you my earnestness and seriousness of purpose in seeking work. Science is too large an interest for me to ever stop work, even though my f­amily w ­ ill always be uppermost in my life.” She informed him that “ever since I entered college in 1945 I have not been without work . . . ​I feel that the time has now come when I can combine part time work easily into my schedule.” Somehow she also had to convince Kiess that she r­ eally did have a compelling interest in spectroscopy. “I believe that I would profit most by the opportunity to work in the Spectroscopy division at the Bureau,” she wrote, and added for good mea­sure, “This is a field I have always been interested in, but only from afar, from the published works of the Bureau.” What Vera did not know, as she carefully considered how to word her appeal to Kiess, was that he was on the verge of retirement from the Bureau of Standards and about to move to the astronomy department at Georgetown University. Her letter was passed to a Dr. Mann and then to a Dr. Broida, at which point the trail went cold.19

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It seems likely that ­Father Heyden caught wind from Carl Kiess of the inquiries Vera was making about opportunities elsewhere. On July 5 he wrote to her, “­Unless the Air Force intends to cancel out the contract in September, we still have funds for you to work h ­ ere for 20 hours per week. That should go on ­until a­ fter 1959. I hope you ­will not leave us as long as the contract holds.” Vera, however, was not yet ready to give up her search for a new opportunity. At the end of July she wrote to Frank Edmondson, the program director for astronomy at the National Science Foundation (NSF). “I won­der if you would know of any part-­time position in Washington that you think would interest me. I have already contacted the Bureau of Standards and the Naval Observatory. . . . ​A lthough I could continue with other aspects of the eclipse prob­lem, I would prefer to develop my interest and become proficient in spectroscopy.”20 Frank, too, was moving on in September, but he had one idea for Vera: the possibility of an opening in the NSF program for a part-­time professional assistant for his successor, Geoffrey Keller. He enclosed a generic application form for federal employment and told Vera she should fill it out and return one copy to him if she was interested. A copy of the completed application went into her filed papers but, if she did send it off, nothing came of it. Reluctantly, perhaps, she accepted Heyden’s offer to continue as a research assistant in the eclipse program. The letter from Vassar College she received in January 1958, asking ­whether she was interested in following in the footsteps of the recently retired Maud Makemson on the faculty at Vassar, very likely surprised and flattered her. But t­ here was no question of her seriously considering a move to Vassar. Bob had just taken up his new position at the NBS and they relied on the support of their families in Washington.21 Vera did manage to extract some purely astrophysical results from the eclipse observations while satisfying the Air Force with the technical reports it demanded. Her paper was accepted by The Astrophysical Journal in December 1958 and published in 1959.22 It was about how the brightness of the Sun’s disk tails off around its periphery, a phenomenon known as “limb darkening.” She set out to create a relatively s­imple formula, but to arrive at it she needed to employ a ­great deal of mathematical analy­sis. Vera acknowledged at the end of the paper that she had discussed ­every phase of the work with Bob, as always her “sounding board.” By 1958, it was becoming clear that the Air Force eclipse proj­ect was unlikely to continue beyond 1959. Looking ahead to the next academic year,

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the resourceful Heyden found new ways to retain Vera. He wanted to keep her at Georgetown as much as she was desperate to find a job as an astronomer. Th ­ ere would be enough money in the observatory’s teaching funds and grant income to make Vera a part-­time instructor and director of research in the program called Special Studies of the Sun’s Spectrum. Instead of analyzing eclipses, her research task would be a study of the characteristic spectrum of iron atoms and the faint dark lines ­those atoms imprint on the solar spectrum. In 1957, she had written to Carl Kiess professing her interest in working in spectroscopy at the National Bureau of Standards. ­Here, two years l­ater, that wish was being granted, if not quite as she envisaged. She was to collaborate with Kiess at Georgetown and with Charlotte Moore Sitterly at NBS.23,24,25 As Vera had said herself, gaining experience in spectroscopy is useful for any aspiring observational astronomer. Nothing could quench her enduring fascination with galaxies, however, and she had been keeping abreast of all the latest research developments. So far, though, she had never been paid to work on galaxies as part of her job. Now t­ here was a chance for that state of affairs to change. Early in 1958, Vera received a letter from Gérard de Vaucouleurs, who had first made contact with her from Australia in 1951, a­ fter he had read the abstract of her pre­sen­ta­tion to the AAS meeting at Haverford (see Chapter 3). De Vaucouleurs had left Australia in 1957 to ­settle in the United States and had taken a position at the Lowell Observatory. His ­career move was about to open up an opportunity for Vera, as well. De Vaucouleurs (1918–1995) had been interested in galaxies since the late 1940s but had been frustrated ­because, in his native France, he ­didn’t have access to telescopes suitable for the research he hoped to do. With his wife, Antoinette, also an astronomer and his lifelong collaborator, he had moved to London in 1950 to improve his En­glish and build up his network of astronomical contacts. While earning his living working for the French branch of the BBC World Ser­vice, he and Antoinette lived near the University of London Observatory, where they renewed their friendship with Margaret and Geoffrey Burbidge, whom they had met in Paris the previous year. Margaret was assistant director at the observatory, and both de Vaucouleurses ­were soon involved—as unpaid volunteers—in observing and in mea­sur­ing spectra. In 1951, de Vaucouleurs engineered for himself a move to Australia. The prospect of cloudless southern skies and observing with a new large telescope

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currently u ­ nder construction attracted him to the Mount Stromlo Observatory. To his ­great disappointment, the 74-­inch telescope remained unfinished through to 1956. Undaunted, he persevered using what equipment ­there was, together with wide-­field cameras he constructed himself. In 1954, he took over r­ unning a 26-­inch refractor at Mount Stromlo on behalf of two American universities, Yale and Columbia.26 As early as 1949, de Vaucouleurs had considered revising the most comprehensive cata­log of galaxies available up to that time—­the Shapley-­A mes Cata­log.27 While looking at the distribution of galaxies, he was struck by a concentration of them, stretching in a ­belt across the northern sky. ­Others had noted it before, but to his knowledge no one had tried to explain it. Even with the ­limited data at her disposal, Vera had identified this ­belt, too, when she wrote her master’s thesis, and she had a­ dopted it as her reference plane in her attempt to detect ­whether galaxies w ­ ere moving together around a common axis. Gérard had been harboring the idea that the b­ elt must be a real physical assemblage of galaxies on a scale much greater than anyone was yet prepared to contemplate—­something much larger than a cluster of galaxies. Emboldened by Vera’s venture into this controversial topic, he had de­cided it was an opportune moment to air his own thoughts on the ­matter. By September 1952 he had put together a paper entitled “Evidence for a Local Supergalaxy,” and it was published the following year.28 He cited Vera’s findings as supporting his hypothesis that the ­belt on the sky is our edge-on view of a pancake-­like cloud of galaxies. He called it a “Supergalaxy,” adopting a term Shapley had in­ven­ted in the 1930s to describe his hy­po­thet­i­cal vision of the Milky Way as a flattened cluster of spiral nebulae. De Vaucouleurs had not seen Vera’s entire thesis at that time and ­later had to admit that, when he wrote his paper, he had misunderstood how she had settled on the belt-­like concentration of galaxies as her reference plane. Although it was accepted for publication (unlike Vera’s thesis), de Vaucouleurs’s paper was received no more favorably than Vera’s pre­sen­ta­tion had been, according to Gérard’s recollection of events.29,30 Throughout the 1950s and into the following de­cade, de Vaucouleurs often felt he was fighting a losing ­battle against the view, generally accepted at the time, that clusters of galaxies are distributed evenly and randomly through space and that superclusters do not exist. He prob­ably saw in Vera, with her fresh mind uncontaminated by establishment views, something of a kindred

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spirit. Ultimately the main thrust of his argument proved to be correct. The particulars of some of his early ideas, however, like Vera’s findings on the rotation of the universe, did not stand up to ­later scrutiny. As de Vaucouleurs put it in 1959, “the ­whole outlook of astronomy at the time was dominated by the search for a pos­si­ble ‘edge’—or for a ‘center’—to the w ­ hole metagalactic system, which was more or less identified with the universe.”31 The universe turned out to be a very much larger entity than most astronomers suspected or ­imagined. While de Vaucouleurs had been working in Australia, he and Vera had no chance to meet, and he d ­ idn’t see a copy of Vera’s unpublished master’s thesis. In March 1958, a­ fter arriving in Arizona, he thought belatedly to write and ask her for a copy of it. The cover letter Vera sent him with the manuscript bubbled over with her enthusiasm for Gérard’s research. “I have been following your super-­galactic work with quite a thrill, as you may imagine,” she exclaimed. “Are ­there any pre-­prints of your recent work which I could get?” She asked that he let her know if he planned to visit the Washington area: “I would greatly appreciate meeting you, and having the opportunity to talk with you.” To leave him in no doubt, she affirmed that “External galaxies are still my greatest interest.”32 Her declaration had its effect. De Vaucouleurs responded immediately, equally enthusiastic about meeting Vera, though he could offer no date. “I would be very pleased to meet you when I go back East, but I have no idea at the moment when it w ­ ill be.” Fi­nally, he added: “If you should consider at any time resuming active work in the field of galaxies I would be pleased if you would let me know. Perhaps we can work out some arrangement for a joint study of super-­galactic rotation and related prob­lems.”33 Was he r­ eally thinking that they might collaborate, or was he simply being polite? It was, ­after all, a rather vague suggestion. Almost a year passed without any further reference to the proposed meeting. Then, in early 1959, de Vaucouleurs left the Lowell Observatory and moved to join Harvard College Observatory. In February he wrote to tell Vera that he would be in Washington in April for a symposium at the National Acad­emy of Sciences. “If the time is con­ve­nient to you, we could arrange to meet in or near Washington on April 28 or May 1.” He had not forgotten his hint from almost a year e­ arlier about collaborating and reminded her about their exchange. “In your letter of March 5, 1958, you expressed continued interest in external galaxies; if at any time you

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Fig. 5.1 Passport photo of Vera Rubin with her c ­ hildren (left to right) David, Karl, and Judy, in 1959. (DTM, Car­n e­gie Institution of Washington)

should wish to resume active work in the field I ­shall be happy to help you in any way I can. In this connection you may be interested to know that I am continuing with NSF support the long-­range program of photometry of galaxies, in the first instance the reduction of the Mt. Stromlo photo­graphs and Lowell photoelectric scans.”34 De Vaucouleurs was referring to a line of research on galaxies he had been pursuing since he was in France in the late 1940s. He had wanted to put into numbers how galaxies vary in brightness from one place to another across the images they pre­sent. To test ­whether he could do this successfully, he had taken photo­graphs of three elliptical galaxies and one spiral galaxy at the Observatoire de Haute Provence. Th ­ ese he had pro­cessed with a photometer, a piece of equipment in which the glass photographic plate moves around over a small light while a photocell mea­sures the amount of light transmitted through the negative image on the plate at dif­fer­ent positions.

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He found that the light of all three elliptical galaxies diminished in the same characteristic way, from their centers, where it is strongest, out to their faint peripheries. He could write a ­simple mathematical expression for it. ­Later, other astronomers began to call his formula the “de Vaucouleurs law.”35 In Australia, de Vaucouleurs had stockpiled a veritable trea­sure trove of galaxy images with a view to analyzing them with a photometer. In possession of a larger sample of galaxies, he might be able to draw more general conclusions. He had already started the task at Harvard, laboriously pro­ cessing the data for a handful of the brightest galaxies, but ­there was much to do by way of calculations on the output from the photometer. It was a slow, tedious, and somewhat routine pro­cess, ­because each galaxy needed careful expert attention. With many examples to compare, he hoped to demonstrate that galaxies of similar shape are also similar in their pattern of light output. If that w ­ ere the case, then mea­sur­ing the light contours of a galaxy might be a way of deducing its distance. Vera invited Gérard and Antoinette to dinner at the Rubin f­ amily home in McKinley Street. Shortly afterward, Gérard wrote to Vera to thank her and Bob for their hospitality and to follow up on their conversation. “I ­shall send you in a few days a step-­by-­step description of the photometric reduction of standardized photo­graphs of galaxies with a numerical example. If you think that your computing facilities are adequate and that you would be able to spare the time to take part in this program, please let me know at your con­ve­nience and we s­ hall see what practical steps we can take e­ ither to secure additional support from NSF or possibly a direct grant to you from ONR.”36 Vera could not contain her impatience to get started and lost no time in responding: “I am quite willing and anxious to work on the prob­lem. I have already spoken to Fr. Heyden, who is also willing that I spend my time and computer time on it. I would like to start some proceedings immediately for getting money, so that it may be available by Fall.” She told de Vaucouleurs that she would do the programming during the summer in preparation and, as an afterthought, inquired: “I won­der if you have any ‘spare’ money so that I could get started in September ­until a grant comes through, in case t­ here is a delay in approval. If not, perhaps I can try to work some such arrangement down ­here.”37 As soon as de Vaucouleurs received her letter, he telephoned Vera. His letter following the call addressed the best way to speed up pro­cessing the

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backlog of accumulated data and suggested that, yes, at least during the initial phase, he could prob­ably support Vera’s work from his own funds.38 The truth was, Vera had been carried away by her enthusiasm and anxiety not to let the opportunity pass. She could not get down to work immediately, b­ ecause she and Bob already had their summer mapped out. In just four or five weeks’ time they ­were leaving with the ­children to spend two months in Eu­rope. The galaxy proj­ect would have to remain on hold ­until her return. The summer of 1959 was truly memorable for the Rubin ­family. They passed eight magical weeks living in a mountain chalet perched high in the French Alps. Each day they awoke to a spectacular pa­norama of Mont Blanc and its neighboring peaks. This idyllic setting was (and remains) home to the prestigious Physics Summer School of Les Houches, which Bob had been invited to attend. The theme of the 1959 school was “The theory of neutral and ionized gases.” The annual summer school had been the brainchild of a French physicist, Cécile DeWitte-­Morette, who wanted to inject new life into physics in France following the turbulent war years.39 She ­later recalled how she built support for her proj­ect and raised money by making male colleagues think the idea was their own. She would engage them in thinking about such a plan and then phone a week ­later to say, “Oh, that idea you told me about was ­great.” Remembering ­those days, she told an interviewer, “I was an intellectual geisha.” 40 DeWitte-­Morette eventually had enough financial support to establish the summer school near the village of Les Houches and to launch it in 1951. From the start, it attracted some of the most distinguished physicists from all over the world. Each summer, around thirty promising young scientists ­were invited to attend for eight weeks during the university summer vacation period. In this hideaway, participants could immerse themselves totally in intellectual activity. It would have been unthinkable for Bob to leave Vera and the ­children ­behind. The ­whole ­family was to go, including Davy, Judy, and Karl—­ages eight, six, and three. Pete, Rose, and Bob’s parents waved to them all as they set sail from New Jersey aboard the luxurious ocean liner SS Nieuw ­Amsterdam, en route to Le Havre in early July. The five of them squashed into one cabin. ­A fter spending a night in Paris, they drove to Les Houches, a distance of over 370 miles (600 kilo­meters).41 Along with the other students,

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Fig. 5.2 The Rubin ­family on board the SS Nieuw Amsterdam in early July 1959, en route from New York to Le Havre in France. (DTM, Car­n e­gie Institution of Washington)

they ­were quartered in s­imple chalets scattered a ­little way out of the village, farther up the mountain from where the lecture hall and main facilities ­were located. The Rubins shared their chalet with a French ­couple and their young sons. Th ­ ere ­were walks in the woods to be taken, blueberries to be picked, and fresh milk to be fetched from where the cows grazed even higher up the mountain. Strictly speaking, Vera was not permitted to attend the scientific ­sessions—­but when astrophysicist Évry Schatzmann arrived to give classes in stellar evolution in the second half of the program, he bent the rules for Vera. Schatzmann’s wife climbed up the road from the village to the Rubins’ chalet several after­noons each week to take care of the ­children so Vera could go to her husband’s classes. By the end of the summer school, Bob and Vera had acquired a taste for hiking in the mountains and had stashed away trea­sured memories of an unforgettable experience. They had made new and enduring friendships, especially with the British astrophysicist Donald Lynden-­Bell and his wife, Ruth, who was a chemist. When it was all over at the end of August, they made the six-­hundred-­ mile (thousand-­kilometer) drive to the Netherlands, where Bob was to spend

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some time networking with other physicists. Vera and the ­children left Bob to it and headed home, this time by air from Amsterdam rather than by sea. When they arrived in New York, exhausted ­after a delayed overnight flight, and hopelessly cluttered with piles of coats and baggage, Pete and Rose w ­ ere 42 ­there to greet them. Back at Georgetown, Vera had work she must do. She was ­going to start teaching a course on the structure and dynamics of the Milky Way galaxy, so ­there ­were lectures to prepare. Like the classes she had attended as a gradu­ate student, hers would be taught in the eve­ning. The timing was ­awkward ­because of the c­ hildren, but the subject was close to her heart and the opportunity was one she c­ ouldn’t pass up.43 On the research side, she needed to make pro­gress with the spectroscopy, already funded by a grant from the NSF. De Vaucouleurs wrote to her in mid-­October, ­after some weeks of silence on Vera’s part. Cautiously, he inquired about the status of their collaboration. “I have been hoping to hear from you a­ fter your vacation in Eu­rope. I trust that you and your husband enjoyed it. Could you please let me know at your con­ve­nience what pro­gress, if any, you have made with the research proposal for work on galaxies? Can I help?” 44 She had not made any pro­gress. A remark from de Vaucouleurs to the effect that the NSF, already supporting him, might not be kindly disposed ­toward putting more money into the same program had discouraged her from even trying the NSF herself. ­A fter the prompt from de Vaucouleurs, Vera and Heyden explored vari­ous other ave­nues without success. So the galaxy proj­ect languished while Vera made headway with the spectroscopy, since neither Georgetown nor Gérard had any “spare money.” Eventually, in January 1960, Vera de­cided she had nothing to lose by calling the NSF. It worked. ­There ­were funds available, said the program director, Geoffrey Keller. She should submit her proposal.45 Vera applied for a two-­year grant, explaining to the NSF that de Vaucouleurs would supply the galaxy tracings from his photometer and she would use Georgetown’s small “computer,” a Burroughs E101, to analyze them. The E101 was a rather strange combination of calculating machine and primitive electronic computer, containing hundreds of valves and diodes. The size of a large office desk, it could be programmed to run up to 128 instructions automatically by inserting pegs into a set of eight perforated boards. The

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operator sat in front of a large, calculator-­style keyboard in the center of the desk and the peg boards w ­ ere set into the desktop on the operator’s right. A magnetic drum could store up to one hundred numbers.46 Optimistically, Vera anticipated that working twelve to fifteen hours per week, with the help of a gradu­ate student, she would complete and publish the analy­sis of the data on a few of the largest galaxies in the first year, “with the remainder of the study appearing in print at the end of the second year.” The NSF was persuaded, and the delayed proj­ect was set to start properly by June of 1960. ­There was, however, to be a short interruption. In the summer of 1960, Vera again traveled to Eu­rope for a study course. This time, she was the participant and Bob was the accompanying guest. Baby Allan, their fourth child, arrived on May 23, but how could she miss the chance to spend two weeks getting up to speed with “Pre­sent prob­lems concerning the structure and evolution of the galactic system”—­and meeting, at last, the g­ reat Jan Oort? Vera had asked both de Vaucouleurs and her friend Frank Edmondson to back her application to attend, writing to both of them on the same day in the previous January. “I am sure I do not need to emphasize to you how ­great my interest is in this subject,” she said to both of them, adding in her letter to Gérard, “I hope our program w ­ ill be the start of my return to this field, and that I can stay in it for good.” 47 The Dutch organizers of the course had chosen Nyenrode C ­ astle as the setting, an enchanting fairy-­tale palace, complete with moat and drawbridge, near Utrecht in the Netherlands. The history of the ­castle goes back to the thirteenth ­century although the pre­sent appearance of the fortified mansion dates mainly from the seventeenth ­century. Since 1946, it has ­housed Nyenrode Business University. Or­ga­nized by a committee of distinguished Dutch astronomers, the course on galactic structure was ­under the auspices of the Netherlands Universities Foundation for International Co-­ Operation (NUFFIC), an in­de­pen­dent body dedicated to fostering international cooperation in education.48 Each set of grandparents cared for two of the Rubin ­children while Vera devoted herself to science between July 28 and August 16. She was one of sixty-­six students from sixteen countries, of whom only four ­were w ­ omen. Twenty speakers, including Jan Oort and Margaret and Geoffrey Burbidge, presented forty-­four lectures in all. Th ­ ere ­were visits to Leiden Observatory and Dwingeloo Radio Observatory, as well as numerous social and cultural

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events, offering many opportunities for networking. At first, Vera was too much in awe of Oort to speak to him, but she “soon had too many questions to stay ­silent.” 49,50 Vera took in every­thing avidly and wrote an article about what she had learned for the magazine Physics ­Today.51 This is the earliest piece she ­later selected for her collection of general writing and talks, published in 1997 as Bright Galaxies, Dark ­Matters. Introducing her article on the Nyenrode experience, she reflects that “The course was a significant event in my professional ­career; the lectures brought me up-­to-­date on astronomical discoveries I had overlooked in the 1950s while getting my Ph.D. degree and raising four c­ hildren with my husband, Bob.” That summer was the beginning of what Vera looked back on as a “remarkable period” in her life.52,53 On her return to Washington, Vera was raring to go on the galaxy proj­ect. By October 22, 1960, she was writing to de Vaucouleurs, who by then had moved to the University of Texas at Austin, to tell him that she had got her program for the Burroughs E101 working perfectly and that it would take her somewhere between two and four weeks to complete the analy­sis for each galaxy. She had run out of data, however—­could he send more without delay? “I ­will be searching the mail anxiously and set to work immediately. ­Shall I plan to send you the results for each galaxy as completed, or wait for a group to be completed?”54 The work was soon in full swing, with Vera concentrating on elliptical galaxies, rather than tackling the greater complexity of spiral galaxies. In early December of 1960 she made a short visit to Austin, and soon afterward the University of Texas appointed her as an unpaid research associate in the astronomy department in recognition of her “valuable collaboration” in its program in galaxy photometry.55,56 Now she had more than enough data on elliptical galaxies to keep her occupied, but in early February the indefatigable de Vaucouleurs deluged her with even more, including some relating to galaxies that ­weren’t ellipticals. This was not what she was expecting. She was uncertain about how to deal with the situation. She was keen on the research and she wanted to keep on good terms with de Vaucouleurs, but now he was asking too much.57 Vera explained her position in a civil yet plainly worded letter. An apology was dispatched forthwith.58 He had lost sight of the fact that she was employed only part-­time on the proj­ect and was sorry if he upset her. Still, he wrote again a c­ ouple of weeks l­ater with more suggestions about the scope and variety of data he could supply to her.

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She might even join him to share some observing with the 82-­inch telescope at the University of Texas McDonald Observatory, he added tantalizingly. The prospect of observing at such a major observatory ­really piqued her interest. She must surely have been aware, from talking to them at Nyenrode, that Margaret and Geoffrey Burbidge had been spending a g­ reat deal of time at the McDonald Observatory, observing galaxies to determine how they rotate and how massive they are. Vera responded with predictable eagerness, while recognizing the practical prob­lems in her way: “Your comments concerning the use of the 82-­inch are quite exciting. I have done no observing (except as a student) and consider this a real void in my background. If some arrangement could be worked out (my ­family makes this seem very difficult) I would be most happy to share one of your runs.” The immediate issue, for her, was how hard she was having to work on the collaboration, and yet she d ­ idn’t want Gérard to imagine that she was not applying herself diligently. “I am sorry to be returning the data to you, but I just have no spare minutes. I have been using the computer three days a week (18 hours) and spend my eve­nings proofreading, setting up data for the next run, rewriting programs and learning what I am ­doing. ­There just is not sufficient time to do more.” Despite the many occasions on which Vera and de Vaucouleurs mentioned potential publication to each other in their correspondence, nothing relating to their joint enterprise appeared in print with Vera named as an author. At the very start of the relationship in 1959, de Vaucouleurs had written, “I would suggest joint authorship of all publications resulting from this common ­effort.”59 By February 1961, however, he seemed to be lowering Vera’s expectations. “While I understand your wish to be ready to publish results as soon as pos­si­ble, I doubt that this is r­ eally needed for a f­ uture continuation of your grant. . . . ​The ­people at NSF are fully aware that this is slow, painstaking work and with the informal annual reports are ready to wait u ­ ntil final and substantial results are r­ eally worth publishing.” 60 Two years on, in October 1963, Vera reported to de Vaucouleurs, naming twelve galaxies on which she had been working. “­These reductions are essentially completed,” she told him, “and w ­ ill shortly be prepared for publication.” 61 But it never happened. Between 1961 and 1964, de Vaucouleurs published five modest papers connected with the program in which Vera was involved, each on a single bright galaxy. Each paper named only him as author. One contained a brief

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acknowledgement of computing carried out by Vera, but that was all. The correspondence between the pair offers no clue as to why Vera was not rewarded with a single publication for any of her efforts reducing de Vaucouleurs’s data, but she must have been disappointed. This may account for why, subsequently, Vera never mentioned in any detail their work together in the 1960s, although they remained friends. Most likely, the proj­ect withered away ­because de Vaucouleurs came to the conclusion that this par­tic­u­lar line of investigation was not ­going to achieve the breakthroughs he had hoped for when he conceived the idea. Research on galaxies moved on, and so did Vera’s c­ areer. The de Vaucouleurs collaboration served as a useful apprenticeship at first, but l­ater became less impor­tant to Vera, except as a source of income for her department. By the time she applied to the NSF for her research grants to be continued from September 1964, she could write that the program of photometry of galaxies was sufficiently advanced that “much of the work can be carried out by gradu­ate students.” The collaboration would formally end when Vera left Georgetown in 1965. Meanwhile, in 1961, Vera was developing a research proj­ect of her own with her students, and a new opportunity for a more productive collaboration was not far over the horizon.

CHAPTER 6

THE CALL OF THE DOME

S

evere weather gripped Washington in the winter of 1960–1961, so Vera’s few days in Texas with de Vaucouleurs had been a welcome relief from the December cold. By early February, she was on her second set of tire chains. Vera was determined not to let snow and ice prevent her from reaching Georgetown Observatory, perched on its hill overlooking the campus, but she moaned to de Vaucouleurs that the weather slowed down her research.1 On a momentous day in the spring of 1961, Yuri Gagarin pi­loted his Vostok spacecraft around Earth. It was a triumph for the Soviet Union, while Amer­i­ca’s pride took a bruising. Less than seven weeks l­ater, on May 25, 1961, President John F. Kennedy affirmed before Congress that the United States’ goal was to send an astronaut to the Moon before the end of the de­cade. Amer­i­ca was set on winning this ultimate trophy in the space race, but the cost was ­going to be, well, astronomical. Illinois Senator Paul Douglas, a former academic economist at the University of Chicago, solicited the opinions of astronomers as to the scientific value of the Apollo program. ­Every member of the American Astronomical Society resident in the United States, including Vera, received a questionnaire. We ­don’t know what Vera’s views on ­going to the Moon ­were, but we do know that she was preoccupied with more distant space, turning her mind to stars ten thousand light years away in the spiral arms of the Milky Way.2 Among the thirty or so part-­time gradu­ate students in the astronomy program at Georgetown, six w ­ ere taking Vera’s eve­ning course on Galactic Dynamics. As a group they possessed considerable expertise regarding star cata­logs. Clayton Smith, for example, had a day job at the US Naval Observatory, in a division that was heavi­ly involved in a major international collaboration to compile a cata­log of 21,500 stars.3 Jaylee Burley (who became Jaylee Mead ­a fter her marriage to Gilbert Mead in 1968) had been a mathematician at NASA’s Goddard Space Flight Center since 1959, the

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year in which it was established. Her work, too, was concerned with cata­logs and data.4 Thanks to the diligence of ­those who spend countless hours of systematic observing to compile cata­logs, astronomers can trawl through a trea­ sure trove of resources to assem­ble data for a research program without ever spending a night observing themselves. Vera conceived an imaginative idea for a class proj­ect that would give her six students excellent experience of research, while addressing a prob­lem that intrigued her personally. Her question was this: Is t­here enough information buried in existing star cata­logs to find out more about how the Milky Way rotates?5 Vera posed her question some ten years ­after radio astronomers had begun to map vast clouds of hydrogen atoms in the Milky Way by analyzing their radio emission at a wavelength of 21 centimeters. ­These observations had revealed beyond doubt a pattern of spiral arms in our Galaxy. A deviation of the wavelength of the signal from a precise value of 21.1061140542 centimeters discloses the velocity at which a par­tic­u­lar cloud is moving t­oward or away from us—­its radial velocity along the line of sight. What t­ hese mea­sure­ ments cannot tell us unambiguously, though, is how fast a gas cloud is rotating around the center of the Galaxy. The situation is dif­fer­ent for stars. At least in the case of intrinsically bright stars, at not too vast a distance, it is pos­si­ble in princi­ple to track their apparent speed across the line of sight—­their so-­called proper motion. By combining t­hese figures with radial velocities captured from their spectra, it’s pos­si­ble to build a more accurate picture of their circulation around the center of the Milky Way. Stars well-­suited to this exercise are ­those classed as O or B by their color and spectrum. ­These massive white-­hot or bluish stars are intensely luminous, and are always relatively young as stars go, ­because their natu­ral lifetimes are short. It was already well-­known that O-­B stars preferentially inhabit the gas-­rich spiral arms in the main disk of the Galaxy, where new stars emerge from their dusty cocoons and youthful stars still linger near their birthplaces. A few studies had been undertaken, but only of nearby O-­B stars. Vera suspected that the existing star cata­logs contained enough data to push the bound­aries of knowledge about the Galaxy’s rotation farther from the solar neighborhood, out to distances of some ten thousand light years, both t­ oward and away from the galactic center. Although sifting through cata­logs for a large enough coherent sample of stars, and then analyzing the data, would involve a ­great deal of hard work, it was

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worth it. They could look for answers to a variety of questions. Are the stars rotating in sync with the gas? Do the stars follow circular orbits in the disk of the Galaxy or pursue dif­fer­ent kinds of paths? And how does the general rotation of the Galaxy change with increasing distance from the center? That last question is most easily understood when it is illustrated in a graphical way, as a plot of average rotation speed against distance from the galactic center. Such a plot is called a rotation curve. L ­ ater in Vera’s c­ areer, the shape of galaxy rotation curves would become the key that unlocked her most impor­tant scientific discoveries. This was the first time she had contemplated constructing one. In 1961, very ­little was known about galaxy rotation curves in general. Astronomers had published the rotation curves of only twenty-­four galaxies, most notably the Andromeda Galaxy, the large spiral nearest to the Milky Way. ­These curves, however, did not extend much beyond the inner regions where glowing stars and gas clouds ­were within ready reach of the instruments and techniques available at that time. The outer regions remained cloaked in mystery. Most astronomers presumed that the tracks followed by stars and gas clouds in the outer parts of a galaxy would be controlled primarily by the gravity of the massive concentration of stars at the galaxy’s center, in much the same way that planets in the solar system are kept in orbit by the gravity of the Sun. In 1619, Johannes Kepler wrote that he had discovered a relationship between a planet’s distance from the Sun and the time it takes to complete an orbit. It is a ­simple mathematical formula. The more remote the planet from the Sun, the slower it moves. In fact, orbital speed diminishes very sharply with distance. Kepler’s formulation of the relationship became known as his third law of planetary motion.6 As a consequence, any situation where the speeds of circulating astronomical bodies follow Kepler’s third law of planetary motion is described as “Keplerian” for short, even if the bodies concerned are not planets. Hard as it was to plot rotation curves for the external galaxies beyond our own, constructing the Milky Way’s rotation curve from within it was also a big challenge. Yet this was part of the task Vera set her students. She thought the ­whole proj­ect through very thoroughly. On July 12, Jaylee Burley sent a long, technical letter to Vera about compiling suitable star data from cata­logs. “I am very excited about the prob­lems which you proposed for using our data,” she enthused. “Thank you for all the thought which you have given to the prob­lem and especially for the well-­organized plan and suggestions

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which you sent to me.” She concluded with, “Thanks again for all your effort, interest and help.”7 Jaylee was communicating with Vera by letter ­because, on June 3, the Rubin ­family had migrated west for the summer, Bob having arranged to spend a few weeks working in a branch of the National Bureau of Standards in Boulder, Colorado. Bob’s parents joined them for a vacation and took care of the ­children while Vera attended a ­couple of meetings in southern California.8 The International Astronomical Union (IAU) was holding its triennial General Assembly in Berkeley from August 15 to August 24. ­These unique two-­week-­long events have remained impor­tant to the worldwide community of astronomers ever since the Union was created in 1919. They provide a locus for numerous scientific meetings for dif­fer­ent interest groups, as well as a structure for attending to administrative m ­ atters. Although Vera could not stay in California long enough to attend the General Assembly itself, she could go to a ­couple of scientific meetings taking place beforehand, scheduled to take advantage of the fact that so many distinguished astronomers would traveling to California from all over the world that month. IAU Symposium 15 at Santa Barbara, August 10 to August 12, was particularly engaging for Vera. Its theme was “Prob­lems of Extragalactic Research.” A ­ fter persuading de Vaucouleurs to recommend her to the chairman of the organ­izing committee, Otto Heckman, she received the necessary invitation.9 In June, a letter describing the administrative arrangements arrived. Vera was not yet established firmly enough in her c­ areer to protest its patronizing sentence: “A program is being prepared for the ladies.” Had this been a few years l­ ater, she would undoubtedly have done so, in strong terms. All attendees at the IAU Symposium ­were also invited to a meeting or­ga­ nized locally in Santa Barbara on the previous two days, exploring “The Instability of Systems of Galaxies.” So, for five days Vera found herself mixing with many of the biggest international names in extragalactic research, some of whom she knew already and many of whom would play a part in her ­future. Among them ­were Margaret and Geoffrey Burbidge, Bertil Lindblad and Per Olaf Lindblad, Jan Oort, Allan Sandage, and Gérard de Vaucouleurs.10 At the symposium, Vera heard Margaret Burbidge recount in detail how astronomers went about the business of securing observations of galaxies with the objective of plotting rotation curves.11 Margaret understood the prob­lems very well b­ ecause she and Geoffrey had embarked a few years ­earlier on a pioneering program of observing for this purpose at

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the McDonald Observatory in Texas. Geoffrey had long been interested in the evolution of galaxies, but it was not something he could investigate without more data on their basic properties, such as their masses—­and that information simply did not exist. Rather than give up, however, he and Margaret set about acquiring the data. And how does one weigh a galaxy? By using its rotation curve. Combining gravitational theory with a rotation curve makes it is pos­si­ble to model, for the part of the galaxy encompassed by the rotation data, how mass is distributed as well as the total amount of it.12 In 1957, Geoffrey, who had been a postdoctoral fellow at Harvard, joined Margaret on the staff of the University of Chicago’s Yerkes Observatory so they would both have access to the 82-­inch telescope of the McDonald Observatory in Texas, which ­until 1963 was run by the University of Chicago on behalf of the University of Texas. Margaret rescued an old spectrograph that had been abandoned in a lumber room in an attic at Yerkes and got it into working order. Though dating from 1939, it was well-­suited to the task and very rugged once repaired.13 At Yerkes, the Burbidges met theorist Kevin Prendergast, a young assistant professor. They recruited him in 1959 to work on interpreting their galaxy rotation curves.14 He also made a pre­sen­ta­tion at the Santa Barbara symposium about his role in the research, explaining how he calculated the masses of galaxies and the distribution of mass within them.15 The threesome already had an impressive list of publications from their collaboration and w ­ ere responsible for thirteen out of the twenty-­four known rotation curves. If the possibility crossed her mind at all, Vera would hardly have dared believe that, within three years, she would be a member of their team and coauthor with them of a string of papers. On her return to Georgetown, Vera picked up the threads of her own research and teaching when the new academic year commenced in the fall. The proj­ect on O-­B stars developed so successfully that by the spring of 1962 she and her students had a draft of a substantial paper, some of it hammered out in late-­night sessions around Vera’s dining-­room t­ able. In April, she presented the results, in the form of two oral papers, at the American Astronomical Society’s 110th meeting in Cambridge, Mas­sa­chu­setts.16 The radial velocities of their sample of stars ­were broadly similar to ­those of the hydrogen gas clouds, they had concluded, but with a lot of scatter around the average. “Deviations from circular motion and random velocities larger than the random gas velocities must exist,” she told her audience.

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The rotation curve mea­sures had thrown up even greater disparities. Despite careful attention to pos­si­ble sources of error, their stellar velocities ­were higher than t­ hose derived from radio observations of hydrogen clouds. Even more disconcertingly, beyond twenty-­six thousand light years from the center of the Galaxy, roughly the distance at which the Sun is located, the rotation curve was approximately flat. Vera and her students emphasized the point in the paper they prepared for publication: “The decrease in rotational velocity expected for Keplerian orbits is not found. It is shown that systematic observational errors ­will not account for the shape of the curve.”17 By the end of July, Vera judged the paper to be in good enough shape, and submitted it to The Astronomical Journal. ­There was just one hiccup: when the editor, Dirk Brouwer, telephoned Vera to say that the paper was accepted but he would not publish the names of students as coauthors. “Then I withdraw the paper,” Vera informed him without hesitation. Brouwer relented, and it appeared in the October 1962 volume of the journal, with Vera heading a list of six authors.18 Vera l­ater recalled that many of the comments she received about that paper ­were “negative and some very unpleasant.” The typical criticism was that “It c­ ouldn’t be correct or the data ­were not good enough.” Its unexpected conclusion about the shape of the rotation curve “apparently influenced no one.” Indeed, she would l­ater ignore it herself, even when she returned to the prob­lem of galaxy rotation a de­cade ­later. More than two de­cades ­later, however, in the face of an accumulation of corroborating observations, astronomers w ­ ere ready to give credit where it was due. One paper, for example, noted that “As first pointed out by Rubin et al (1962) . . . ​­there is mounting evidence that the rotation velocity is steadily rising in the galactic disc for r > r0 [that is, at distances from the center greater than the Sun’s].”19 Vera and her students had been correct all along. The publication of a paper with her students was by no means the end of this line of inquiry for Vera. In fact, it was just the beginning of her research program on the rotation of the Milky Way; she would pursue this for another two or three years, ­until other topics took priority. Her second paper, in collaboration with just one of the coauthors of the first paper, Jaylee Burley, extracted further details from the data on their selected O-­B stars by concentrating on how stars within about 6,500 light years of the Sun are moving. Despite the criticism of the first paper, they stuck to their guns: “Evidence

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is presented for a rotation curve which is flatter than the generally ­adopted rotation curve for R > R0.” They submitted the paper in August 1963, and it was published in The Astronomical Journal the following February. Vera recorded her thanks to Bob “for his continued help with all phases of this work,” but the first of the acknowl­edgments went to “Martin F. McCarthy, S. J., visiting astronomer at Georgetown College Observatory from the Vatican Observatory, for many stimulating discussions, and for critically reading an early draft of this paper.” Martin McCarthy (1923–2010) had arrived at Georgetown in early 1962 and was to serve as visiting professor for the 1962–1963 academic year.20 Five years Vera’s se­nior, he had received his doctorate from Georgetown in 1951 but had left to undertake theological studies just before Vera joined in 1952. He had been on the staff of the Vatican Observatory since 1958, where his specialty was classifying stars from their spectra, and he was already an experienced observer. Before long, Martin and Vera ­were collaborating on vari­ous proj­ects as colleagues and friends. He became a frequent visitor to the Rubin household—­a lmost an a­ dopted member of the ­family. It was the start of an enduring professional friendship that flourished throughout their lives, all the more unusual for the time b­ ecause it was between a Jewish ­woman and a Roman Catholic priest. Although their very dif­fer­ent lives meant that opportunities for them to meet in person seldom arose a­ fter 1963, Vera and Martin w ­ ere rarely out of contact by letter for more than a handful of weeks. Vera kept in her files hundreds of letters, postcards, and greetings cards sent by Martin between late 1963 and 1996. Many of his letters are in tiny handwriting on thin airmail paper. His subjects ranged freely through astronomical topics of common interest, events in the Vatican, his travels, and personal and ­family ­matters. Sadly, Vera’s letters to Martin do not seem to have survived, but it is clear from what Martin writes that she was as prolific a correspondent as he was. Vera began the new academic year in 1962 not only with an in­ter­est­ing new colleague, but also with new status as a member of the faculty. In June she had learned she was to be promoted to assistant professor. One of her tasks in that year was to conduct the PhD oral examination of George Coyne, SJ, who would go on to become director of the Vatican Observatory between

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1978 and 2006. He had just completed four years as a gradu­ate student and was defending a thesis on the reflective properties of the surface of the Moon. ­L ater he would recall an incident he witnessed on that examination day, which he saw as an example of the “doggedness” that characterized Vera’s research throughout her c­ areer.21 Coyne had walked up to the observatory somewhat early and was strolling around, trying to relax. About thirty minutes before the exam, he spotted Vera with Martin McCarthy, who was his other examiner, in the library, busily examining books on a shelf he had never visited. ­A fter they had left, Coyne went to the bookshelf and found they had been checking out the spectrum of Earth’s atmosphere. Why? His thesis was concerned with the properties of moonlight. But, of course! The light from the Moon had to pass through Earth’s atmosphere before he could analyze it. Why had he not thought of that? Coyne panicked, and rapidly prepared an answer to the inevitable question he now anticipated. When Vera raised the issue, he mumbled something based on all of twenty minutes’ focused thought, unsupported by anything in his thesis. He recalled that Vera complimented him on an intelligent response which, however, “required a ­great deal more data.” ­W hether that last-­minute thinking saved the day we ­will never know. He passed the examination. Martin McCarthy brought observing skills to Georgetown Observatory that no one on the faculty possessed. For the first time, Vera had an accomplished associate who trained her in practical techniques, albeit with the ­limited facilities at Georgetown and ­under nighttime skies polluted by the lights of Washington. By June 1963, a­ fter benefiting from McCarthy’s tutelage, she had gained enough confidence to apply for telescope time at a major observatory in her own name. In a letter to Helmut Abt, an astronomer at the newly established Kitt Peak National Observatory near Tucson, Arizona, she wrote: “­Until recently, I have done very ­little observing—­a lmost none. This past year, Fr. McCarthy and I have been using the Ross 5-­inch at Georgetown, often with an objective prism, and he has been an excellent teacher. I believe that I could quickly become familiar with the equipment, and be working on my own.”22 McCarthy also brought to Georgetown a proj­ect on star classification that he wished to complete during his year ­there. It was to result in a joint paper with Vera.23 The bulk of the photographic observations they used ­were made in Italy at the Vatican Observatory by F ­ ather Patrick Treanor, SJ,

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and dispatched to Georgetown, where Martin and Vera worked together on analyzing them. The Vatican Observatory, which is located in the grounds of the Pope’s summer residence at Castel Gandolfo, about sixteen miles (twenty-­six kilo­ meters) southeast of Rome, had a brand-­new telescope, the 38-­inch (or 98-­centimeter) Vatican Schmidt camera. At the time, it was one of largest of its kind in the world. The purpose of this par­tic­u­lar design of telescope is to image wide areas of sky. As well as being able to take normal photo­ graphs, in which stars appear as sharp dots, the Vatican Schmidt could be converted so that each star image was drawn out into a spectrum. This was achieved by placing over the front aperture of the telescope a large, circular, glass plate, graded in thickness from one side to the other. This accessory is known as an objective prism. Each of the thirteen glass photographic plates dispatched to Georgetown mea­sured twenty by twenty centimeters and covered an area of sky five degrees square. They ­were littered with hundreds of streaks, each one a tiny spectrum. ­These plates w ­ ere of a type that registered blue light and the near ultraviolet part of the spectrum, not vis­i­ble to the h ­ uman eye. Martin and Vera ­were concentrating on G-­type stars, which are similar to the Sun, and focused their attention on thirty-­nine of ­these. A question Martin wanted to answer was ­whether t­ here was anything in the ultraviolet part of the spectrum that could help distinguish between dwarf and ­giant stars of the same temperature and color. ­Giant stars ­were once ordinary dwarf stars, such as our Sun, but have swelled im­mensely and become more luminous with age. As it happened, although they found they could easily use existing criteria to make the distinction, they came up with no fresh ones. An impor­ tant part of the exercise, however, had been to test the capabilities of the new telescope. Speaking thirty years l­ater, at the dedication of the 1.8-­meter Vatican Advanced Technology Telescope at Mount Graham in Arizona, McCarthy recalled, “It was an exciting time for us and a fine first indication to me that our Vatican Schmidt could give us superb spectra.”24 In January of 1963, a celebrity visit spiced up a cold winter’s day and gave Vera a unique opportunity to get informed about the “space race.” Not quite a year ­after becoming the first American to orbit the Earth, astronaut John Glenn spent a day at Georgetown University. The main reason he came to campus was to film an interview sponsored by the US Information Agency, as part of a series produced for audiences in South Amer­i­ca. Glenn took ques-

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Fig. 6.1 Vera Rubin with astronaut John Glenn (center) and Martin McCarthy in the office of the president of Georgetown University on January 11, 1963. (DTM, Car­n e­gie Institution of Washington / Georgetown University News Ser­vice)

tions from four Latin Americans, two of them journalists and the other two Georgetown students, about the US space program. Then, Glenn sat for a separate interview with the Georgetown student radio station, WGTB, which ­Father Heyden—­a radio enthusiast as well as an astronomer—­had set up when he first arrived at the university in 1946. A photo­graph in the university archives shows a smiling Glenn seated on a sofa in the university president’s office, flanked by Vera on one side and Martin McCarthy on the other.25 A few weeks ­later, the Rubin ­family received the exciting news that Bob had been awarded an NSF se­nior postdoctoral fellowship, which would allow him to spend the academic year 1963–1964 in the physics department of the University of California, San Diego. It had been a joint decision by Bob and Vera that they should find some means by which they could spend time in southern California. Bob was always thinking of ways to support Vera’s ­career development, and Vera had already had a taste of the opportunities

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that might be on offer during her short visit to Santa Barbara in the summer of 1961. She now had more self-­confidence: on the west coast, she would be able to expand her horizons through observing experiences she could never dream of back east, at Georgetown Observatory. It was surely no coincidence that Bob chose to take up his fellowship at the university where Geoffrey and Margaret Burbidge had settled in, having migrated from Yerkes Observatory in 1962. All Vera needed now was to secure a temporary position—­ ideally with the Burbidges. Martin McCarthy may well have been involved in the plan, too. Vera applied to Georgetown University for leave of absence on April 2, and just two weeks ­later, she and Martin traveled to Tucson to attend the 113th meeting of the AAS and pre­sent their joint paper on the classification of G–­t ype stars.26 Two networking encounters during that trip ­were to be of far more lasting significance for Vera than the pre­sen­ta­tion of the paper. It was during a visit to the nearby Kitt Peak National Observatory that she had a conversation with Helmut Abt about applying for observing time. And seeing the Burbidges gave her a chance to express her bold wish to work with them while Bob was on his fellowship. Geoff Burbidge suggested they should meet for lunch. “I did not know that lunch would also include Allan Sandage,” she l­ater recalled. “All the talk during lunch was about astronomy. I passed their test, prob­ably b­ ecause, unlike many astronomers in Washington, I read The Astrophysical Journal carefully, sometimes cover to cover.”27 It was a tough test, ­because Sandage was an eminent and influential observational cosmologist. He had worked with Edwin Hubble and, since 1958, been on the staff of the Palomar Observatory, at that time part of the Car­ne­gie Observatories. A few weeks l­ater, Martin McCarthy composed the letter of recommendation Geoffrey Burbidge needed to appoint Vera, and sent her a file copy. Martin’s remarks w ­ ere perceptive, brimming with admiration, and remarkably prophetic about the personal qualities that would earn her both wide re­spect and academic distinction as her ­career blossomed. More than anyone other than Bob and Vera themselves, McCarthy understood how liberating some time away from Georgetown would be for her: During the past two years it has been my privilege to be associated with Dr. Rubin ­here at Georgetown. I have had an opportunity to see her engaged in her research with galaxies and in prob­lems of galactic structure and also to hear her speak at lectures and colloquia. In all this I have found her abili-

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ties exceptional, her generosity unflagging and her sense of honesty and integrity in scientific investigation outstanding. In informal conversations and especially during the past year when we have cooperated in research proj­ects, I have found her to be a splendid colleague, a keen and careful worker and a very frank critic of our work. In any new proj­ect she penetrates to the core of the prob­lem with directness, surety and ease. Her students, without exception, speak highly of her lectures and her direction of their research in Stellar Statistics and Galactic Dynamics. Her awareness of which prob­lems in astronomy are of importance and the imagination which she brings to a solution of ­these make her work of g­ reat interest to her colleagues. The opportunity of working at the University of California ­will be for her a very impor­tant and most fruitful one. I believe that in making it pos­si­ble for her to work with your group, you w ­ ill be helping not only her and the University but the entire astronomical community. She and her husband and ­children make a very wonderful ­family group. Her presence at Georgetown ­w ill be missed during the coming year but this year of g­ reat opportunity, which the position at La Jolla w ­ ill afford her w ­ ill, I am sure, be a most rewarding one.28

Her appointment was rapidly approved, and Vera lost no time in making her first formal request for telescope time. On June 4 she contacted Abt, writing to him that she would be working the coming September through June in the physics department in La Jolla and would like observing time at Kitt Peak. She explained her idea of following up her studies of O-­B stars so she could penetrate farther into the reaches of the Galaxy by observing stars whose brightness is more greatly dimmed by distance. It was clear, however, that her main objective was simply to observe something—­anything in fact. “If for any reason this program is not practical, radial velocities of stars (particularly ­giants) in clusters, or any program you would want to suggest, would ­really be fine,” she pleaded. “Any suggestion you might offer would be most welcome. I am most anxious to start observing and hope that this can be worked out.”29 Kitt Peak National Observatory had been established in 1958 with federal funding as the first truly national fa­cil­i­t y for astronomy in the United States—­not belonging to any individual university or organ­ization. Vera was entitled to apply, in competition with other astronomers; it was ­t here for them all. In 1963, it was equipped with one operational telescope, a 36-­inch (0.9-­meter) reflector, and an 84-­inch (2.1-­meter) one was u ­ nder construction.

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Vera’s first grant of observing time was the four nights of October 24–27, 1963. Her proposed program proved to be entirely practical despite the anxiety she had expressed in her letter to Abt. That first observing session was a ­great success and Vera subsequently made four more trips to observe with the 36-­inch at Kitt Peak—in February, March, and November 1964 and March 1965, for a total of twenty nights. She bagged 118 spectra of thirty distant stars as well as some thirty spectra of standard comparison stars. Ultimately, a­ fter completing all the mea­sur­ing and analy­sis, she wrote up her results in a 1965 paper for The Astrophysical Journal.30 A few weeks before Vera and f­ amily had set off for California, the track of a total solar eclipse had swept across North Amer­i­ca, mostly through Alaska and Canada but just clipping the United States in Maine. Vera, Bob, and Martin McCarthy made the trip to Maine together to view the spectacle.31 At about 5:45 pm on July 20, 1963, in the words of journalist Harold Hartley, “night fell three hours ahead of time.” He colorfully captured the cosmic drama: It even had sound effects. A jet squadron from Dow Air Base at Bangor tracked and filmed the moon’s shadow across Maine, adding symphonic thunder to the grandeur of the scene. . . . ​Clouds played along with the eclipse like ­children following a circus parade, and a soft haze drifted like wispy smoke through the pines. And the gulls headed for Duck Island, where they roost for the night. . . . ​It was a minute to remember, as if someone had turned out the light in a room, then fumbled for the switch and turned it on again. That is the way it was on the eastern tip of Maine t­ oday.”

Hartley also reported that “At the University of Maine in Orono, about 900 professional and amateur astronomers w ­ ere gathered. . . . ​The astronomers got together to­night for a chicken barbecue at Orono to compare notes, talking a language nobody knows but themselves.”32 Martin, Vera, and Bob surely joined in that fun. On August 10, 1963, McCarthy headed home to the Vatican Observatory, embarking from New York on board the ocean liner SS Constitution for Naples. A ­couple of weeks l­ater, Bob, Vera, and the four ­children, then aged between three and twelve, set off to drive the entire breadth of the United States, weighed down with baggage and camping gear. Up before sunrise each morning, they would set off at about 4 am, take a break about five hours ­later for breakfast, then press on ­until about 3 pm. Fi­nally, they reached the spacious ­house they ­were renting, overlooking the ocean in La Jolla.33

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McCarthy, by now back in Castel Gandolfo, was thinking of Vera and on September 3 wrote to her, “Yesterday, 2 Sept, it occurred to me that perhaps by this time you s­ hall have reached La Jolla and tired from the journey be ready for a plunge in the Pacific.” He continued, “Many thanks for your fine letter from Detroit. Let me assure you Vera that I agree perfectly with you that we should not mind goodbyes since it means that we ­shall have seen each other again. B ­ ecause of you and Bob and the ­children and your folks, my leaving Washington (though tinged with sadness) was not the very painful ­thing I thought it might be. I was happy for the work we w ­ ere able to do together t­ here, and also for the many good times we enjoyed together. Especially for the chance to share so many . . . ​­family feasts I s­hall always be grateful.”34 His guess was correct—­the Rubins had made it, and l­ater the same day, ­a fter opening his own mail and finding a letter from Vera, Martin again wrote to her: You are safe in your new home at last ­a fter what sounds like a wonderful trip. Your picture postcard of Lake Jackson was most appreciated. . . . ​I am sending by airmail the proofs of our article and I think it looks very fine in print. . . . ​ Fr Treanor writes from ­England that he liked the paper and thinks we went just about far enough with the material available. For that we have to thank VCR [Vera]; it’s a lesson I believe I learned from you last year: when and how to write finis to a paper. The paper was r­eally much improved by our criticism and work in July.35

Vera’s office in La Jolla could not have contrasted more with the cramped Georgetown Observatory. She was allocated a desk in the physics department, ­housed in a new building on a pier extending out over the ocean. Margaret’s office was next door, and Geoff’s farther down the corridor.36 The small campus nestling t­ here had only recently been established, as a development from the Scripps Institution of Oceanography which had been at La Jolla since 1905 and became part of the University of California in 1912. The Burbidges ­were among the first faculty members to be recruited and, ­until the start of the 1964 school year, ­there w ­ ere no undergraduate students, only research staff. Margaret and Geoff ­were ­running a production line in galaxy rotation curves. In addition to Vera, they had with them a young British postdoctoral researcher—­Joan Crampin, an applied mathematician. Abundant photographic observations just waited for someone to carry out the necessary

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mea­sure­ments on them. Vera was set to work. “Geoff was the boss,” she l­ater recalled, and at times he applied subtle pressure on her by dangling an incentive. On one occasion, for example, she was told that if she made the mea­ sure­ments and wrote the paper by Friday, she would be considered the lead author and named first on the paper. If she missed that deadline, Geoff would take what she had done, complete the paper himself over the weekend and put Margaret’s name first.37 Vera coauthored a total of nine papers with the Burbidges, all published in The Astrophysical Journal between 1964 and 1965. Kevin Prendergast and Joan Crampin w ­ ere also coauthors on some of them.38 It was about six weeks a­ fter arriving in California that Vera prepared to fly to Tucson for her first solo observing stint at Kitt Peak. She had four nights on the 36-­inch, from October 24 to 27. “Next week I go to Kitt Peak to get radial velocities of O and B stars in the anticenter,” she wrote to Sarah Lee Lippincott on October 15, by way of explaining why she could not accept an invitation to speak to Lippincott’s students at Swarthmore College. “I de­cided to try my hand at the observational end, and I envy you all your time at a telescope! My heavy sweater from Holland ­will come along also.”39 While Vera was in Tucson, a lengthy letter arrived—­a lmost three thousand words—­from Martin in which, among many other ­things, he predicted the emotions she would experience at the telescope: “You w ­ ill be scared, then delighted, then upset at some uncertainty in the weather and when you have finished you w ­ ill be amazed at what you have accomplished, at how much you have learned, at how anxious you are to do more, and fi­nally at how ­really tired you are some days ­after your run is finished.” He added some words of advice: “One of the secrets of observing which I mentioned to you last year when we w ­ ere teaching, writing, examining, arranging colloquia and giving talks (and while you in addition ­were cooking, managing the ­house­hold, entertaining so graciously and shopping) was that on a mountain observatory you can spend full time observing and preparing to ­observe. . . . ​I urge you to try to ‘build into’ your schedule a c­ ouple of good rest and relaxation periods during the ­couple of weeks a­ fter your days at KPNO.” 40 Vera had obviously conveyed to Martin how happy she was with her exciting new experiences. “It is ­really wonderful news that ­things are ­going so very splendidly with you at La Jolla,” he goes on. “I can tell that this is ­really proving to be every­thing you expected and much, much more and I am so glad for you, Vera. Your letters have been g­ rand and reflect the g­ reat joy you

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have in the work you are engaging in and contentment that you and Bob have at La Jolla. . . . ​How nice that you and Mrs. B are working so well together.” The torrent of words flowed on ­until Martin suddenly ended with “Well, Vera, I’ll conclude now as I have to get ready for to­night’s observations. I thank you again for your wonderful letters.” But before reaching that close, he had digressed into one of his chatty anecdotes, which so often reveal something about Vera. “By the way, I d ­ on’t think I told you that on my way to the boat on 10 Aug ­after my phone call to you I paid a flying visit to the M[useum] of M[odern] A[rt]. . . . ​Leaving my bags in the lobby I found the Van Gogh and know now why it is one of your favorite t­ hings. Magnifico.” Naturally, the Van Gogh in question was The Starry Night, which the artist had painted a­ fter being inspired by the view of the sky just before dawn through his win­dow at the Saint-­Paul asylum in Saint-­Rémy, in June 1889. La Jolla and Georgetown may have seemed worlds apart to Vera as she enjoyed her very dif­fer­ent life in California, but she was not allowed to forget the realities back at Georgetown Observatory. Francis Heyden was struggling to manage the bud­get for astronomy, and to find lecturers willing to teach the multiplying number of undergraduate and postgraduate students ­eager for the astronomy classes. He relied on a mixture of postdoctoral assistants and scientists who worked locally, in organ­izations such as NASA and the National Bureau of Standards, and who ­were willing to teach classes in the eve­nings. On top of all his usual pressures, Georgetown Observatory was responsible for cohosting the American Astronomical Society’s ­December 1963 meeting in Washington.41 Heyden typed a somewhat downbeat letter to Vera on November 4. “Since I must have my salary bud­get ready for next year by December 1, 1963, I hope that you ­will not think I have gone mad in setting up plans for the academic year 1964 to 1965.” ­A fter relating some of his administrative dilemmas he comes to the real point: “I was ­going to murder you by asking you to take the introduction to astrophysics. . . . ​The question is, can you take an undergraduate course for one semester along with the gradu­ate course in galactic dynamics?” 42 More teaching meant less time for research, of course, and the letter must have left her with the ominous feeling that ­things in the astronomy department w ­ ere not ­running smoothly. On November 22, 1963, President John F. Kennedy was assassinated, to the g­ reat shock and grief of Americans and p ­ eople around the world. On November 27, Martin McCarthy wrote to Vera from Rome: “­There ­will be

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a g­ reat sadness this year as we observe Thanksgiving Day, for our much loved President is dead. I know I share this sadness with you and Bob and all of our countrymen as we mourn our JFK, courageous to the end. . . . ​The effect of the news h ­ ere was for me most revealing: each of the community: Germans, Austrians, En­glish, Brazilians, came to extend their condolences and to praise the brave young President. The next morning, I walked through the town to the Schmidt dome and passed first ­under the Vatican flag at half mast and then noticed that ­every h ­ ouse had hung out its red, white and green Italian flag and set it a half mast. The policemen and the villa­gers extended their sympathy to me. . . . ​I have offered Mass three times for the soul of Pres. Kennedy.” 43 The next time Vera heard from Heyden was at the end of January 1964. It seems that she had expressed reluctance about undertaking the additional teaching. “You have me in a quandary over courses for next year,” he wrote, rather delicately, but then put on the pressure. “The dean and the science faculties have required full time professors to be responsible for two courses or the equivalent. Of course, the research courses taken by gradu­ates and the experimental course taken by four or five undergraduates can be big time consumers. . . . ​I do have to apportion out some of ­these tasks to my full time faculty b­ ecause my part time p ­ eople . . . ​do not share this work with me. Next year someone ­will have to teach the four undergraduate courses as well as the eight gradu­ate courses.” 44 Heyden went on to plead that he needed more full-­time faculty members to serve as “slave d ­ rivers.” He was having to take most of the research courses himself, but some of them “possibly ­because of me,” he admitted, “have not been very successful during the past semester.” At least three of his research students had “not done one bit of work.” He had cancelled two assistantships ­because the students ­were “loafing on the job.” Indeed, he reported, “Four months went by with hardly any effort on their part.” The dean of the college had ordered him to fire another assistant b­ ecause of complaints against her by undergraduates, and yet another student had attended only five classes and handed in no assignments. Heyden wrote again on April 20. “I hope you have been around me long enough,” he began, “to know that this department operates with a maximum of confusion and delay just like any other organ­ization.” Perhaps it was intended as a joke, but by then, Vera had gained enough experience of working elsewhere to realize that not all organ­izations ­were so chaotic. The tale of

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woe continued, with mentions of prob­lems with students, finding teachers, and delivering the research required by the grants and contracts that kept the department ­running.45 More letters followed in May, detailing difficulties with research grant proposals. Heyden’s succession of letters related a rather sorry story and could have done ­little to lift Vera’s spirits as she prepared to leave California ­behind and return to Georgetown. Nevertheless, she and Bob w ­ ere beginning to feel ready to go home. They missed the trees—­and no doubt their extended ­families, too. Before they departed, though, Vera made sure to visit Maud Makemson, who had moved to California on her retirement from Vassar College in 1957. The ­whole Rubin ­family went over to San Diego for the reunion. It was the first time since Vera’s graduation from Vassar that the two had seen each other.46 When in early August 1964 it was time for Vera and Bob to say goodbye to La Jolla, they loaded the ­children, two lizards, and one horned toad into the car, along with their baggage and camping gear, and drove back to DC.47 She recalled the trip as “leisurely and lovely, with more camping, hiking and green trees.” 48 No sooner had they arrived back at their home on McKinley Street, however, than Bob and Vera ­were repacking their bags. This time they ­were ­going briefly to Eu­rope, and leaving the c­ hildren in the care of grandparents. Three years had elapsed since Vera had attended the IAU Symposium in Berkeley. Now, the 1964 IAU General Assembly was taking place in Hamburg, Germany, and unlike in 1961, attendance at the main event became a priority. Vera had been given the status of “invited participant,” and during the course of the General Assembly would be admitted as a full member of the IAU. She could just manage nearly two weeks away before she needed to be back in Washington. Her ­children would also be heading back to school and Vera wanted enough time to or­ga­nize her domestic life in advance of the new academic year. The Hamburg General Assembly was the first opportunity for Vera and Martin to get together since they had departed Georgetown twelve months ­earlier. ­A fter the General Assembly, Martin wrote to her from Castel Gandolfo on September 28 and, among many other t­ hings, remarked on the very pleasant day they had spent in Lübeck. But turning to a more serious issue before chatting about astronomy, Martin brought up an aspect of the ­prob­lems at Georgetown Observatory that had surfaced at the General Assembly.

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Marjorie Williams, the assistant program director for astronomy at the National Science Foundation, had been a member of the United States contingent at the IAU General Assembly. She had taken the opportunity to speak plainly to both Vera and Martin about the unsatisfactory nature of the grant proposals the NSF had been receiving from ­Father Heyden’s department, a state of affairs that had “become more critical” while Vera was out on the west coast. “I judge that the officials at NSF want to help Georgetown,” Martin wrote, but “serious imperfections in the way of presenting the scientific side of proposals and defects in the fiscal part of the proposal ­were leading to delays, objections and complaints from both scientific review boards and from the financial ­people.” He left it at that in the letter, writing, “Oh well, you know all this.” 49 Georgetown’s paperwork challenges might have been depressing to consider, but Vera was buoyed by a thrilling invitation received out of the blue in Hamburg. A ­ fter the closing banquet at the Hamburg meeting, as she and Bob ­were stepping away from the dance floor, a smiling Allan Sandage casually approached them. Would Vera be interested in observing with one of the telescopes at Palomar or Mount Wilson? She could scarcely believe what she was hearing. Officially, ­women ­were not allowed to observe at ­either of ­these Car­ne­gie Observatories sites, ­because of, as the standard excuse went, their “lack of facilities” for ­women. Vera was aware that, almost a de­cade e­ arlier, Margaret and Geoffrey Burbidge had felt the impact of this discriminatory policy. Margaret had been urged by a colleague to apply for a Car­ne­gie postdoctoral fellowship in 1955 that would allow her to observe at Mount Wilson. But when the colleague inquired on her behalf, he was told that, b­ ecause the observatory had only one toilet, a w ­ oman could not be awarded the fellowship.50 Another “standard reason” not to give ­women time on the telescope, Burbidge ­later wrote, was the fear that the night assistants at the telescope would not gladly take direction from them. Geoff, therefore, applied for and was awarded the fellowship, while Margaret secured a dif­fer­ent position. Allan Sandage used his influence to make it pos­si­ble for Margaret to participate in shared observing proj­ects with Geoff—­albeit unofficially. Pushed on the ­matter by not only Sandage but Caltech, Ira Bowen, director of the Mount Wilson and Palomar Observatories, relented. Henceforth, Geoff’s observing proposals would be treated as joint proposals with Margaret, and she could observe with Geoff—­but they would have to stay in the small, wooden cottage on

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the observatory site, bring their own food (and wine), and use their own car. The standard thinking about the night assistants proved to be baseless.51 Having been instrumental in creating opportunities for Margaret Burbidge to observe, Sandage had now de­cided to help Vera. He recognized in her another potentially outstanding observer who was facing bureaucratic obstacles simply ­because she was a ­woman. She followed up his invitation promptly with evident delight. On October 17, 1964 she wrote to him, full of gratitude and enthusiasm: “First I want to thank you for all your help— in suggesting that I apply for observing time, and in your many suggestions. I am enclosing the request for you to look over, if you d ­ on’t mind. If you have any suggestions, I would appreciate them.” Her proposal asked for five nights on the 48-­inch Palomar Schmidt telescope. Her idea was to take wide-­ field photographic plates of the sky along a section of the Milky Way that she could use in three dif­fer­ent proj­ects. One was searching out more distant O-­B stars to extend the work she had started with her students on the rotation of the Galaxy. She also had in mind detecting dim, nearby, blue stars to find out more about their distribution, and also starting a program to find variable stars. Her letter to Sandage goes on: “­A fter ­really quite a bit of thought I felt that some observations of this sort with the [Palomar] Schmidt w ­ ere r­ eally of more interest to me than the [Mount Wilson] 100-­inch coudé. If you have any major objections to this kind of program, I w ­ ill ­reconsider. . . . ​This ­really has been lots of fun and even if it is not successful, I ­will have enjoyed it thoroughly. Thanks again for the encouragement.”52 An anxious five weeks for Vera then passed before Sandage sent a handwritten reply, first apologizing for the delay, and then offering an assessment: “The proposal is good but it suffers from being too ambitious.” He recommended that she concentrate on one, central theme if she wanted to impress the committee that would be allocating the telescope time. “Hit them hard on the discovery program for 13th to 18th magnitude blue stars to get the rotation curve,” he urges. “Send a copy of your rotation curve you showed me last year to illustrate the method. . . . ​Keep this proposal short (just as you have). . . . ​Get it in as soon as pos­si­ble to Babcock. All best regards and you have my support.”53 She took the advice, redrafted the proposal, and mailed it to the director of the Mount Wilson and Palomar Observatories, by then Horace Babcock. Two nerve-­racking months ­later, at the beginning of February 1965, a letter from Babcock fi­nally arrived, conveying the good news that “the Observatory

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Committee has given a favorable recommendation on your request for five nights’ observing time with the 48-­inch Schmidt at Palomar Mountain, and I am therefore happy to approve it. To judge from your program, you would prob­ably like to have this time next November.” On the accommodation arrangements he says, “We can offer you lodging in the ‘monastery,’ a rather unusual arrangement perhaps but I think you ­will find it reasonably comfortable and satisfactory. Unfortunately, the Observatory has not as yet been able to provide special quarters for observers on the distaff side.”54 The “monastery” was the nickname for the building near the telescopes where ­people working on the mountain at night ­were accommodated. ­There was a communal living room, kitchen, and dining room on the ground floor, and two floors of bedrooms above. Pairs of bedrooms shared one bathroom, which was located between them and could be accessed from e­ ither bedroom. Up to this point, the ­people staying in the monastery had been, without exception, men. Clearly, broaching the subject of sleeping arrangements with the first ­woman observer was awkward for Babcock. Rather than use the word “­woman” or “female,” he chose the quaint terminology of the “distaff side.” The bathroom arrangements w ­ ere of l­ittle importance to Vera. What ­mattered was that she had achieved a breakthrough, a first. Of course, she accepted by return of post, in a letter politely crafted to allay Babcock’s concerns. “I am certain that the living quarters in the ‘monastery’ ­will be satisfactory,” she reassured him. Then she added a touch of sly humor: “Would you also please thank the anonymous person who penciled in ‘usually’ where the instruction sheet for Guest Investigators states ‘. . . ​it is not feasible for ­women to undertake an observing program.’ ”55 It was a wink at the real­ity of professional discrimination, but also a hint that her indignation was being stirred. That same day she wrote to Sandage, too, and began with gratitude: “The thanks go way back, from first suggesting I submit the proposal, then helping me get it in order, and then what­ever magic got it approved. I have ­really been walking on air ever since Dr. Babcock’s letter arrived, telling me the proposal had been approved, and I am certain I owe most of the thanks to you. I thought of sending you some wild tele­gram message of thanks when the news came, but de­cided I must behave like a more sedate ‘lady-­astronomer.’ ”56 Next, she informed him of her big decision: “I have turned in my resigna-

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tion to Georgetown, ­after some very serious thought. It was a difficult step to take, for I had worked for many years to try to make the department one of which I could be proud. However, I fi­nally de­cided that t­ here w ­ ere too many ­things of which I could not at all approve, so I ­will be leaving.” About three weeks ­earlier, she had addressed her letter of resignation to the dean of the gradu­ate school. Dated January 13, 1965, it was short and to the point: I am writing to tell you that I have de­cided to leave Georgetown University this June. I entered Georgetown in 1952 as a gradu­ate student, and have been associated with the Observatory almost continually since then. During ­these years, the rapid expansion of the field of Astronomy, and particularly the growth of Astronomy in the Washington area, has presented the Astronomy Department with many prob­lems. I have always hoped that I could help the Department in the solution of ­these prob­lems, and have worked very hard ­toward this end. However, it has become clear lately that on many fundamental questions, my views do not coincide with the direction in which the Department is moving. In par­tic­u­lar, the ­handling of the gradu­ate students, the direction of their course work, their assignment to research programs, and the supervision of their thesis work does not satisfy my own personal standards. Therefore I feel that I have no action open to me other than to resign from my position at the end of the academic year. I am taking this step with ­great sadness, for Georgetown University and the Astronomy Department have been a very dear part of my life for many years.57

­Later, when Vera was occasionally asked why she had left Georgetown, she usually said that having teaching responsibilities would not have allowed her enough time for observing and research. While that may also have been true, it was a rationalization of the move that came ­later. Her con­temporary letters strongly suggest that her decision to leave Georgetown was precipitated by the mismanagement of students, for whom she cared deeply, and a growing fatigue with the chaotic state of the department’s operations. She recognized she was getting nowhere in trying to change the situation. As it turned out, nobody managed to save astronomy at Georgetown: ten years ­later, the department was shut down permanently. In contrast to the daily frustrations Vera endured at Georgetown, she had found real contentment in the quiet calm of the observatory dome, ­under an expanse of dark, starry sky. F ­ ree from the cares of a dysfunctional university department, ­f ree to explore what­e ver questions about the universe grabbed her interest, she had begun to think that she might make a real

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contribution as a researcher. It would be her ideal escape route from a situation that had become intolerable. All the same, leaving Georgetown was emotionally wrenching. She had resigned without having a definite job offer elsewhere. She had agonized over what to do, weighing her options in conversation not only with Bob but also with Martin, who was in Washington for dental treatment between early November 1964 and the end of January 1965. Very likely, Martin’s presence helped her make her momentous decision. He was a fellow astronomer, trusted mentor, and confidante who knew Georgetown intimately—­and who also understood Vera. When it was time for Martin to depart again, on January 28, Bob and Vera traveled along to New York and gave him “a very elegant and wonderful send-­off” before he boarded the Cunard liner RMS Carinthia the following day.58 Vera’s f­uture had been on all their minds as the Rubins and McCarthy parted. It was the very last ­thing they discussed just before Carinthia left port. Responding to Vera in a letter shortly a­ fter his return to Castel Gandolfo, Martin clarified the philosophical advice he had proffered then. “My last words to you and Bob on the boat meant only that we ­shouldn’t review again and again the motives and ­causes for a decision which you made together with full honesty and candor and can never therefore regret though we may always wish that t­ hings might have been other­wise. . . . ​It’s only the beginning for you Vera so go forward in peace and enjoy e­ very bit of the fun that lies ahead for you.”59 And that’s exactly what she did.

CHAPTER 7

THE DELIGHT OF DISCOVERY

T

he memorable months in La Jolla between September 1963 and August 1964 had changed Vera. The Burbidges w ­ ere genuinely interested in her ideas and Margaret was an inspirational role model. It was the first time Vera had been taken seriously as a real astronomer. She returned to Washington believing in herself, with the confidence that o­ thers would take her seriously, too. Not least, she had discovered her aptitude for observing, along with the plea­sure it gave her.1 With her newfound self-­assurance, she was prepared to risk resigning from Georgetown University. Several other organ­izations in the Washington area employed astronomers and Vera had her sights on one in par­tic­u­lar. From the moment she had first set foot in the Car­ne­gie Institution’s Department of Terrestrial Magnetism (DTM) on a spring day in 1952 to meet with George Gamow, she had harbored an ambition to work t­ here. She had instantly felt at home in the calm atmosphere of the building and its semirural setting. Located only a few blocks from where she now lived on McKinley Street, it had become familiar territory as she had taken to dropping by occasionally. The notion of joining the staff, however, had been l­ ittle more than a fantasy—­ until now. Could she, with her unconventional astronomical background and parental responsibilities for four young c­ hildren, possibly be accepted into this hallowed establishment? Astronomy was only a minor activity ­t here, and ­there had never been a w ­ oman on its scientific staff. Further, why should a Department of Terrestrial Magnetism employ an optical astronomer at all? The curiously named DTM was established in 1904 by the fledgling Car­ ne­gie Institution of Washington (CIW).2 Its original goal was to map the magnetic field of the ­whole of Earth but, by 1929, that mission had largely been accomplished. Rather than see DTM shut down, researchers t­here, including Merle Tuve, began branching out into other areas of physical

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science, especially nuclear physics. Then came World War II and the work on the proximity fuze that led to the establishment of the Applied Physics Laboratory (as described in Chapter 4). ­A fter the war, scientists at DTM pursued an eclectic mix of interests. The organ­ization’s annual report for 1964–1965 collects the research at that time ­under thematic headings: Experimental Geophysics, Theoretical and Statistical Geophysics, Laboratory Physics, Biophysics, and—as a distinct instrumentation proj­ect—­Image Tubes for Telescopes. ­There was no group as such for research in astronomy. Just one permanent member of staff, a radio astronomer named Bernard (Bernie) Burke, was fully engaged in what could be properly described as astronomy, though Tuve himself and visiting researchers also contributed to the program. The annual report bundled radio astronomy incongruously with experimental geophysics. In fact, on the opposite side of the continent, ­there was a separate, and world-­famous, department in the CIW ­family entirely devoted to astronomy: the Mount Wilson and Palomar Observatories in California. This prestigious establishment, run in conjunction with the California Institute of Technology (CalTech), was staffed by some of the most distinguished contributors to the field, u ­ nder 3 the direction of Horace Babcock. Vera knew t­ here was at least one astronomer at DTM, however, b­ ecause she had struck up a friendship with Bernie Burke, whom she saw at the regular colloquia held at Georgetown for astronomers from all over the Washington area. They shared an interest in galaxies, and Vera occasionally visited DTM to use the library and chat with Bernie. She had become interested in comparing radio and optical observations to better understand the rotation of the Milky Way and she pondered how best to pursue this topic. Maybe t­ here was scope for her and Bernie to work more closely—­under the same roof, in fact? She was not dependent on Georgetown for observing time on optical telescopes, and already had several observing runs lined up for 1965. Her fourth visit to Kitt Peak was scheduled for January. Then she would join the Burbidges at McDonald in April and, thanks to Allan Sandage, she had the prospect of observing with the Palomar Schmidt at the end of the year. Vera had not dared to make any kind of inquiry about employment at DTM before resigning from Georgetown. Poaching staff from another institution was considered bad form: she feared DTM could reject her for that reason alone if she did ­things in the wrong order. Once her resignation

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letter was dispatched on January 13, 1965, however, she had nothing to fear on that count. Vera dropped in to see Bernie, and blurted it straight out: “I want a job at DTM!” Bernie was utterly taken aback. Vera ­later reported to Bob that Bernie could not have been more startled if she had asked him to marry her. Regaining his composure ­after the initial shock, Bernie suggested Vera stay for the community lunch, where she would meet some of the other researchers. The director, Merle Tuve, showed up, too. “Why ­don’t you stand up and tell us about what ­you’ve being ­doing?” Tuve said to Vera, waving in the direction of a blackboard. So she took the floor and described what she had done with the Burbidges.4,5 Among the p ­ eople around the lunch t­ able was a young physicist named W. Kent Ford Jr. (born 1931). He had been working for several years on developing an electronic device called an image tube, which could rec­ord many more of the photons collected by a telescope than a photographic plate alone. The principal aim of his proj­ect was to incorporate image tubes into astronomical spectrographs. Potentially, this pioneering technique could increase by tenfold or more a telescope’s ability to rec­ord the spectrum of a faint object. The practicalities of fitting image tubes to spectrographs ­were still being worked out on the 100-­inch telescope at Mount Wilson and on two telescopes at Lowell Observatory: the 24-­inch Morgan telescope and the 69-­inch Perkins telescope (which was upgraded in 1965 with a new 72-­inch mirror). The story of the Car­ne­gie image tube had begun in 1954, at which point the 200-­inch (9.1-­meter) Hale telescope at Palomar Observatory, by far the largest in the world, had been operational for four years. Despite the fact that astronomers worldwide, then just as now, ­were ­eager for such bigger and better telescopes, t­ here ­were no near-­term prospects for o­ thers of this class to be built. That prob­lem had set Merle Tuve to thinking about how the ­per­for­mance of many existing telescopes, ranging from 80 to 120 inches, category might be enhanced to match the capability of the 200-­inch Hale telescope, especially in spectroscopy. For de­cades, astronomers had made use of photoelectric tubes to mea­ sure the total amount of light from individual stars, but this was a more daunting proposition: Tuve wanted to employ a photoelectric technique to enhance two-­dimensional images with sufficient contrast and resolution, and over an area large enough, for recording spectra and ­whole fields of stars. To

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tackle the challenge, Car­ne­gie formed the Committee on Electronic Image Converters, which ­later morphed into the Joint Committee on Image Tubes for Telescopes. In February 1954, the Car­ne­gie Corporation of New York awarded a grant of $50,000 to the Car­ne­gie Institution of Washington to fund an exploratory program aimed at developing electronic image converters to increase the capabilities of large telescopes. The cooperative proj­ect, chaired by Tuve, drew on contributions from five organ­izations: Mount Wilson and Palomar Observatories, the National Bureau of Standards, the US Naval Observatory, Caltech, and DTM. Kent Ford joined the proj­ect early on. A grant from the image tube committee had funded his work on a crucial piece of technology—­researching the physics of thin metallic films—­while he was a doctoral student at the University of V ­ irginia from 1955. DTM recruited him in 1957 when he had completed his doctorate. By 1959, Ford was in effect leading the proj­ect, negotiating with industrial suppliers and assessing several early models of image tubes. As testing progressed, be began capturing astronomical spectra himself, although he was by his own admission not ­really an astronomer.6 By 1964, the proj­ect had specified a suitable type of image tube and arranged for it to be manufactured by the Radio Corporation of Amer­i­ca. Twenty ­were ordered. The first few ­were installed in vari­ous observatories in early 1965.7 With g­ reat satisfaction, Tuve could write in DTM’s annual report for 1964–1965, “The initial stated aim was to minimize the highly privileged position occupied by the small group using the 200-­inch telescope. It appears that this goal has now been reached.”8 Neither Ford nor Tuve was an astronomer and DTM d ­ idn’t even have the equipment, never mind the know-­how, to mea­sure and decipher spectrograms. Consequently, they could not truly assess from the perspective of an astronomer the quality and usefulness of the observations they w ­ ere producing. Now, unexpectedly, a real astronomer who could do ­these ­things had appeared out of the blue, at lunchtime on a mid-­January day, asking for a job. Kent had photo­graphs he had secured of some stellar spectra in a recent experimental observing session. Digital imaging still lay in the f­ uture, so ­there was only one means of making a permanent rec­ord of the spectra appearing on the light-­sensitive phosphor screen of the image tube. They had to be photographed. Tuve handed Vera one of the photographic plates. Could she determine the radial velocity of the star from the spectrum on the plate? Yes, of course

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she could. She took the small piece of glass back to Georgetown and pro­ cessed it with a mea­sur­ing machine ­there. She must have duly delivered the answer—­a lthough, when Vera told the story years l­ater, she could not remember exactly when or how. Tuve did not get back to her immediately. She waited anxiously for two or three weeks. It appears she then asked Martin McCarthy to put in a good word for her, prob­ably reasoning that a letter from Martin to Tuve would have the same positive effect as the one he had written to Geoff Burbidge when she wanted the job in La Jolla. Writing to Vera on February 22, Martin praised her most recent “wonderful letter (with a news density which was most remarkable)” and then added, “Please tell me what you want (i.e. regarding when and to what address), regarding the letter to Tuve; I can send it whenever you wish.” ­There’s no evidence of ­whether or not Tuve actually received a letter from McCarthy. It could have been coincidental that Tuve made contact early in March. Vera was at Georgetown Observatory when she took a telephone call from Tuve and was offered a position. When could she come over to discuss details? “In ten minutes,” she told him. Tuve indicated he was thinking of sometime the following week. “No,” insisted Vera, “I’ll be with you in ten minutes.” Martin McCarthy must have been one of the first p ­ eople to hear the news ­after Bob. When he wrote to her on March 13, he was already aware that Vera had been hired to demonstrate and exploit the capabilities of the new image tube spectrographs. “If I w ­ ere you,” he advised, “I would quite ‘put on the shelf’ our proposals for observations at KPNO u ­ ntil you have had a full year or 10 months at your new work.” He predicted that image tube work would prove “very demanding.”9 By chance, Vera had walked into DTM just when she could take advantage of a brand-­new technology and her skills ­were needed to test its effectiveness. It was an amazing and unanticipated opportunity. “We w ­ ere fortunate in having Dr. Vera Rubin, formerly with the Georgetown College Observatory, join the DTM staff in April,” acknowledged the image tube committee in its annual report about three months ­later. “Her previous work in astronomical spectroscopy and radial velocity mea­sure­ments in par­tic­u­lar ­will be of ­great help in the application of tubes to observation prob­lems.”10 The expectations laid on her could not have been clearer and Vera was content that she could and would deliver on them. At last she had the life

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she had dreamed of, as an observational astronomer. Over the course of 1965 she would work at four dif­fer­ent observatories and use five dif­fer­ent telescopes in six observing sessions. The arrangements for her employment w ­ ere made informally. Vera explained to Tuve that she needed to go home at three o­ ’clock in the after­ noon, when school let out for the ­children. That ­wasn’t a prob­lem. They would pay her two-­thirds of the full-­time salary. And could she begin work right away—­say, on April 1? Vera ­couldn’t wait to get started at DTM, but she had told Georgetown she would leave at the end of the academic year, and she was personally concerned for her students. Fortunately, all the classes she taught w ­ ere in the eve­nings. Her offer to complete her teaching for the year, even though she would no longer be paid by Georgetown, was accepted.11 At DTM, Vera was offered a choice of office accommodation: she could share with Bernie or have her desk in Kent’s office, cluttered though it was with the vari­ous parts of a spectrograph he was putting together to take to Flagstaff Observatory. She knew she was ­going to be working on the image tube observations, so she happily settled in with Kent. Complementing each other’s skills and interests, the pair bonded as colleagues from the start, just as Tuve hoped they would.12 Although Vera left her office at three ­o’clock each after­noon, her astronomical work continued at home. She sat at the long dining room ­table with the ­children working beside her, when they ­weren’t ­running around. Bob worked t­ here, too, many eve­nings. Studying was a f­ amily affair.13 The huge ­table, always littered with books and papers, was legendary; anyone who visited the Rubin ­house­hold commented on it. For Allan Rubin, the image of his ­mother and f­ather at that t­able, their work spread over its surface, is among his strongest recollections of childhood.14 Vera acknowledged that life was not easy when the c­ hildren w ­ ere young. Sometimes she felt she was just muddling through. House­hold chores took up precious minutes. In 1999 she revealed, “When I had a distasteful task, perhaps washing the kitchen floor when it had gotten to the state that feet would stick to it, I would say in a very loud voice, ‘Do you think that Margaret Burbidge is washing her floor?’ ” But one day when she phoned her old friend to discuss something, Margaret answered the phone and said, “Could I call you back? Sara [her d ­ aughter] and some friends are h ­ ere and I’m in the ­middle of scrambling an omelette.” Vera recalled that she “hung up with

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Fig. 7.1 Vera Rubin working at home in the mid-1960s (date unknown). (DTM, Car­n e­gie Institution of Washington)

g­ reat joy” at the discovery that this ­great astronomer and role model “shared the mundane duties of sisterhood.”15 Vera’s capacity for work d ­ idn’t go unnoticed. About six months ­after she started at DTM, Tuve told her, “Vera, your idea of part time seems more like time and a half to me!”16 But it ­wasn’t a question of her having the fortitude “to persevere.” As she put it in an interview, “I was unable to stop!”17 Less than a month into the new job, Vera left for about ten days in late April 1965 to join the Burbidges for an observing session on the 82-­inch ­(2.1-­meter) telescope at the McDonald Observatory. She had arranged this back in November 1964, figuring it would be a useful learning experience.18 The spectrograph the Burbidges w ­ ere using was placed at the telescope’s prime focus, located high up above the main mirror inside the open metal framework that serves as a “tube.” Large reflecting telescopes often allow for this. Blocking the incoming light from the central part of the main mirror has ­little impact on the telescope’s overall per­for­mance, but extra mirrors and lenses inserted to direct the light to a more easily accessible place outside the tube cause some of the precious light to be lost en route. If a telescope is large enough, ­there may even be room for the observer to be squeezed next to the instrument inside a “cage” at the prime focus. The 82-­inch was not large enough, however, to accommodate a prime focus observer’s cage. Instead, the observer had to be positioned precariously

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in midair by means of an elevator. Margaret Burbidge described what it was like. “Access to that focus was obtained from two electrically operated “pulpits,” off a bridge which ­rose up and down within the dome slit. Each pulpit could be manually cranked up, so that with suitable manipulations one could reach in and insert plate holders or other instrumentation directly at the prime focus. . . . ​At first, the experience up t­ here produced a slightly dizzy sensation, as one looked down upon the primary mirror and felt the awesome responsibility of knowing that it was as much as one’s life was worth to fumble and drop anything down onto the mirror.”19 Vera must have described the same sensation to Martin McCarthy, for he wrote to her on May 7, “Yes, the platform motion is quite an experience and I am sure you have mastered it. Each platform is a bit dif­fer­ent. . . . ​Picturing you in a pulpit is fun.”20 The McDonald adventure had been exciting and had given Vera experience of using a prime-­focus spectrograph. It did not, however, produce any published research for Vera and she did not extend the collaborative work she had started with the Burbidges at La Jolla. Instead, on her return from Texas, she immersed herself in learning how to get the best from the image-­ tube spectrograph. She had less than a month to prepare before her first visit with Kent Ford to use the Perkins telescope located at Lowell Observatory. They w ­ ere taking with them the latest version of DTM’s own spectrograph, designed and built by Ford and colleagues. E ­ arlier in the year, Ford had helped to install image tube systems at Yerkes Observatory and Mount Wilson. A third had been sent to Lick Observatory, and yet another had been supplied to Kitt Peak. All four of ­these ­were for the sole use of the staff at the vari­ous observatories. The arrangement with Lowell, though, was dif­ fer­ent. The director ­there, John Hall, was on Car­ne­gie’s image tube committee and welcomed Ford and Rubin as frequent guest observers. Although the new DTM spectrograph they ­were taking would be left at Lowell for its staff to use, Rubin and Ford ­were to have ample opportunity to use it themselves for observing what­ever they chose.21 So, how was Vera to decide what kind of objects they should be targeting? Where to start? Since the driving motivation ­behind the image tube proj­ect was to enable more modest telescopes to match the per­for­mance of the 200-­ inch, it made sense to go straight for the spectra of some very faint objects of the kind only the 200-­inch could have tackled previously. Apart from the tenfold gain in ability to rec­ord light generally, the image tubes also had an-

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other advantage over straight photography: they w ­ ere sensitive to light over the entire range of the vis­i­ble spectrum and beyond, from the ultraviolet to the near-­infrared. Unaided photography of the red end of the spectrum was especially problematic. So how could their advantages be put to good use?22 Just two years ­earlier, extragalactic astronomy had been revolutionized by the astonishing discovery of a bizarre new cosmic phenomenon: quasi-­ stellar objects (or quasi-­stellar sources)—­the objects we now know as quasars. Frantic work was underway to understand their nature, requiring spectra from which their redshifts could be mea­sured and their distances calculated, on the assumption that the redshifts w ­ ere due to the expansion of the universe. The chain of events that led Maarten Schmidt to recognize the first quasar in 1963 goes back to the 1950s and the development of radio astronomy ­after the Second World War.23 Radio astronomers began to survey the sky and draw up cata­logs of the radio sources they could detect. One such cata­log was the Third Cambridge, or 3C, Cata­logue from the Mullard Radio Astronomy Observatory at the University of Cambridge in E ­ ngland. Some sources ­were easy to correlate with vis­i­ble objects, such as massive galaxies or the remnants left ­behind by stars exploding as supernovae. The identification of many other sources, however, some of them very intense, remained a prob­lem ­because nothing stood out among the many faint stars in the relevant part of the sky. The task was all the more challenging ­because very accurate positions w ­ ere difficult to mea­sure with most radio telescopes of the day. Caltech’s optical astronomers working at Palomar, including Rudolf Minkowski and Walter Baade, w ­ ere desperate to find out the precise locations of radio sources so they could know where to direct their 200-­inch telescope. To get ­these accurate positions, they commissioned the first telescopes at Owens Valley Radio Observatory.24 In 1962, Thomas Matthews, a radio astronomer at Owens Valley, and Allan Sandage made the connection between three of the most power­ful celestial radio sources (3C 48, 3C 196, and 3C 286) and what appeared to be stars showing very weird spectra.25 Before the first version of their paper could be published, t­here was a dramatic development. Radio astronomer Cyril H ­ azard and colleagues, using the 64-­meter (210-­foot) dish at Parkes in Australia, had taken advantage of a fortuitous celestial coincidence. In 1962, the Moon passed several times directly in front of another intense radio source, 3C 273. The precise moment when the Moon blocked the radio signal

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had pinpointed the radio position of 3C 273 with unpre­ce­dented accuracy.26 Without delay, Maarten Schmidt turned the mighty 200-­inch ­toward the spot in the sky identified by the radio astronomers and found what seemed to be a thirteenth-­magnitude star and a faint wisp or jet. Then he obtained the spectrum of the “star.” Initially, the spectrum was a baffling puzzle. Then, in a moment of ­great insight, Schmidt realized that a series of features making a distinctive pattern in the spectrum resembled well-­k nown emissions from glowing ­hydrogen—­but only if the w ­ hole spectrum w ­ ere shifted to the red by a f­ actor of 0.16. This was a large redshift, although by no means the largest recorded for a galaxy. The real mystery was that this object appeared star-­like and yet its implied distance was enormous if its redshift was due to the expansion of the universe. If this “star” was in real­ity the bright nucleus of a galaxy, that galaxy would be a hundred times more luminous than any so far identified with a radio source, and yet it could be no more than a few thousand light years across. A prodigious source of energy would have to be powering the nucleus of this galaxy, and it was not obvious what that source might be.27 The starting gun had been fired in a race to find more radio quasars. By 1965, 3C 9 held the rec­ord for the greatest redshift, at 2.012. Then in 1965, Sandage discovered objects that had the properties of quasars—­except that they ­were not radio sources. He called the radio quiet objects “quasi-­stellar galaxies.” The characteristic shared by quasi-­stellar radio sources and quasi-­ stellar galaxies, which made both of them stand out from other celestial objects, was their extraordinarily power­ful output of ultraviolet light. It was a property that enabled astronomers to home in on more such objects very quickly.28 With such extraordinary developments sending shock waves through the world of astronomy, Kent and Vera had plenty of intriguing extragalactic objects on which to try out the new DTM spectrograph. And image tubes, with their unique ability to enhance the red part of the spectrum, had an advantage when it came to observing objects with what ­were considered at the time to be relatively large redshifts. Vera selected NGC 5548, NGC 7469, and 3C 273 among other objects for the May observing list.29 Both NGC 5548 and NGC 7469 are so-­called Seyfert galaxies, named for the astronomer Carl Seyfert, who drew attention to their peculiarities in 1943. The Burbidges had already studied NGC 7469 in some detail, publishing their results in 1963. Like a quasi-­stellar galaxy, a Seyfert galaxy had a small,

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very bright nucleus, and the Burbidges had noted this similarity to some of the radio galaxies.30 3C 273 was the prototype quasar. Its spectrum had already been well-­studied, but it would be a good test subject for comparing what the image-­tube spectrograph on a 69 / 72-­inch could achieve alongside the 200-­inch. Vera came back from Lowell elated. “I de­cided that the image tube work was ­going so well, that with a l­ittle hard work we could be getting some exciting results this coming season,” she told the Burbidges. “With 2-­hour exposures we have faint results, prob­ably mea­sur­able, maybe not. . . . ​Our plan is to spend several weeks late in July-­August back at Lowell. . . . ​If all this goes well, we w ­ ill try to get time on a larger telescope, 84-­inch [Kitt Peak] I hope, and r­eally try for more faint results. Perhaps you can come out to KP some time and watch the fun.”31 From the very beginning, ­there was rivalry between DTM and the CIW observatories in California. That Vera had raised the subject in her regular correspondence with Martin McCarthy is clear b­ ecause, on May 30, he wrote, “I do not know enough about the setup of CIW to comment on the Pal[omar]-­DTM race for image tube spectra of QSSs [quasi-­stellar sources]. You are quite correct that lower resolving power w ­ ill suffice if you can ‘snatch ­every photon’ coming from the source.”32 It seemed that Horace Babcock, director of the Mount Wilson and Palomar Observatories, did not approve of DTM crossing into his territory and hiring an astronomer. Vera and Kent ­were not deterred, however, from joining the competition to determine the redshifts of remote objects, such as quasars—at least for the time being. Vera was so caught up in her enthusiasm for observing that she even de­ cided to forego the opportunity to attend a NATO international summer school, The Kinematical and Chemical History of the Galaxy, held in the second half of August 1965 at Herstmonceux C ­ astle, the home of the Royal Observatory in ­England. Martin was g­ oing, as w ­ ere many of the world’s leading researchers, to exchange ideas on what had been, u ­ ntil very recently, the topic closest to Vera’s heart.33,34 She and Bob did, however, take a short break away from the oppressive summer heat in Washington before Vera needed to go to Lowell for the second time. For them, a summer vacation usually meant visiting a scientific institution somewhere, and that year Bob secured an invitation to Brookhaven National Laboratory, on Long Island, New York. Martin knew Vera well enough to be sure that, for her, “a summer

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in the sun with the c­hildren (and a few back issues of The Astrophysical Journal and the New Yorker) ­will be just ideal.”35 ­A fter Brookhaven, Bob went along with Vera and Kent to Flagstaff for some firsthand experience of what observing at Lowell was like. Vera chose another assortment of potentially demanding targets to test the capability of the image-­tube spectrograph against photography, concentrating on its superior per­for­mance with red light. She was in charge of deciding what to observe, making the finding charts, and guiding the telescope, while Kent’s main responsibility was to set up the spectrograph and ensure that it worked correctly. They did not keep to rigid demarcation lines, though. In the eyes of Peter Boyce, the staff member at Lowell charged with ensuring that the 69 / 72-­inch Perkins telescope ran smoothly at night, they w ­ ere a ­great team. He was often in the dome with them in the years when they w ­ ere frequent guest observers.36 One of the challenges Vera needed to overcome was that of pointing the telescope at objects so faint they could not be seen directly by the person operating the telescope. She prepared charts in advance giving the accurate positions of nearby stars (known as guide stars) that they could see. Then, as she described it, “at the telescope, in almost total darkness, we would mea­sure from the vis­i­ble star to the blank spot where we should observe.”37 A Letter in The Astrophysical Journal announced their results for four objects from the August run: a radio galaxy (3C 33), two quasi-­stellar galaxies (3C 48 and Ton 256), and a recently discovered “infrared star” in the constellation Cygnus. Their success, Kent and Vera wrote, illustrated “the ease of obtaining observations in the red with this equipment compared with conventional photographic techniques.” The chosen galaxies had all been studied spectroscopically by astronomers at Palomar and Caltech, such as Schmidt, Sandage, and Jesse Greenstein, so it ­really was a head-­to-­head comparison. The paper pointed out that six-­hour exposures had been made on the 200-­inch to mea­sure a redshift of 0.3675 for 3C 48. Vera had determined a redshift of 0.368 using exposures of only forty-­six and twenty minutes, on a 69-­inch telescope.38 While Vera was at Lowell, Martin was at Herstmonceux with Sandage and Schmidt. “Can you imagine both Sandage and Schmidt feeling “by-­ passed?” he wrote to Vera on August 25. “They told me of hopes they have of using i.t. [an image tube] with the 200-­inch and are quite chagrined that

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the 84-­inch and now 69-­inch have been used previously and with such success.”39 Without a doubt, the sense of competition was growing. Vera was keen for Martin to share in her exciting new venture in person and had been working on a scheme. Martin’s special interest was cool, red stars and the image tube was particularly suited to observing their spectra. She and Kent had already demonstrated this by taking spectra of three well-­k nown red stars during their first test run in May. Vera persuaded Tuve to invite Martin to visit DTM and find some funding for him. The Lowell director, John Hall, agreed to give Martin the privileges of a guest observer.40 On August 18, 1965, she was in a position to tell McCarthy the good news. ­Because it was DTM business, Vera kept a copy of her letter. She wrote: It is my very pleasant duty to invite you to work with us at DTM on your fall trip to the US. . . . ​A s you know, the image tube work is ­going spectacularly and we anticipate that we ­shall be piling up observations. In addition, we are most anxious to get other observatories interested in using image tubes in their “normal” observing. DTM and Car­ne­gie have a long history of visiting research workers, many of them (particularly on the American seismic programs) Jesuits. We believe that you would fit in and feel much at home ­here. . . . ​The results from the Lowell observing continue to be exciting. . . . ​ Come join us in the delight of discovery!41

Martin responded immediately. “Your wonderful invitation has quite overwhelmed me. . . . ​Thank Dr. Tuve for sending it and thank you for arranging it.” He went on to explain that he would need to consult the director of the Vatican Observatory, F ­ ather Daniel O’Connell, but that their paths would not cross u ­ ntil September 20. “The prob­lem is, as you well know, ­Father Heyden and Georgetown,” he noted, but Vera obviously did not know. She annotated the reply for Tuve’s benefit: “I am not certain I understand all this. He seems to feel that ­after my leaving Georgetown, Fr Heyden would not understand his joining us ­here.” 42 Martin was sensitive to the fact that he would be staying with the Jesuit community at Georgetown, when Heyden seemed to have taken Vera’s departure e­ arlier that year rather hard. Martin had commiserated with her, writing in May 1965, “Sorry t­hings d ­ idn’t go better with you and Fr H. I wrote in February and got no answer.” 43 Martin was not g­ oing to let the dismay harbored by Heyden stand in his way, however, and on September 20 he accepted the invitation to join Vera and Kent that fall.44 It was the first

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of two or three visits Martin made to Lowell as part of a modest collaboration between DTM and the Vatican Observatory over the next two or three years. Vera’s hectic year of observing culminated in mid-­December with her trip to Palomar for five nights at the 48-­inch Schmidt telescope. When she had submitted her proposal to search for distant O-­B stars twelve months ­earlier, Vera had presumed she would be continuing her research program on the rotation of the Milky Way. She had no idea she would be working with Kent Ford at DTM and that the focus of her activities would shift so dramatically. Still, she had ­every reason to go ahead. She could not be sure exactly how her ­future program of research would work out, and she was not ­going to give up her chance to make history as the first w ­ oman permitted to observe at the most prestigious observatory in the world. Vera was allocated a bedroom on the second floor of the “monastery.” She noted that a velvet rope had been placed discreetly across the foot of the staircase leading up from the first floor. The first night was cloudy, so the Caltech astronomers James Westphal and Konrad Rudnicki, who ­were due to observe on the 200-­inch, gave her a guided tour. In the course of the tour they came to the one toilet, with its sign on the door: Men. “This is the famous toilet,” announced her guide. And famous it was, particularly among female astronomers, having been the feeble excuse for denying observing time to w ­ omen. The next time Vera came to Palomar, about five years l­ater, in a flamboyant gesture, she cut out a paper skirt and taped it to the male silhouette on the door.45 Fortunately, the weather changed for the better on the remaining nights of her observing run. She returned to Washington, exhilarated by her experience, in possession of eight or so fourteen-­inch square plates of sections of the Milky Way and one centered on the Virgo cluster of galaxies. Each plate covered about forty-­three square degrees of sky and was peppered with the images of thousands of stars and galaxies, but she could assure Babcock that “the plates are very usable, and crowding and overlapping of images is no prob­lem at all.” Every­one had been very helpful and she had found the telescope “truly a joy to use.” 46 Nevertheless, in the months that followed, her mission to discover more about the rotation of the Milky Way by observing distant O-­B stars lapsed in the face of new priorities.47

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Fig. 7.2 Vera Rubin with Jim Westphal in December 1965 on the balcony of the dome of the 200-­inch telescope at Palomar Observatory (now known as the 5.1-­m eter Hale Telescope). (DTM, Car­n e­gie Institution of Washington)

The only plate that received any real attention from her was the one covering the region of sky around the Virgo cluster of galaxies. DTM had started a program to give research experience to promising students, and one of ­these students came to work alongside Vera during the summer of 1966. She was Sandra Moore, soon to marry and change her name to Sandra Moore Faber. Having just graduated from Swarthmore College, she spent the summer at DTM before starting gradu­ate school in the astronomy department at Harvard. Sandra helped Vera search the Virgo plate for faint, exceptionally blue objects that might be something more exotic than an ordinary star, and she contributed to a paper published the following year.48,49 Sandra Faber returned to DTM in 1970, when she was working on her doctoral thesis for Harvard. In effect, Vera became her informal supervisor during her final two years. Vera had a profound influence on Sandra, as she did on many young astronomers. Like Vera, Sandra was working on galaxies and she wanted to be an observational astronomer rather than a theorist.50

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Sandra made a big impression on Vera, too. She went on to have a distinguished ­career at the University of California at Santa Cruz, where she was named University Professor of Astronomy and Astrophysics, and received many honors recognizing her outstanding achievements.51 In 2020, she became the fourth w ­ oman to win the Gold Medal of the Royal Astronomical Society: Vera had been the second (1996) and Margaret Burbidge the third (2006). Babcock had not immediately granted Vera’s request for time on the ­4 8-­inch Schmidt in the last quarter of 1966 to continue the O-­B star ­program—­and that was prob­ably wise. She had put this to him in October 1965, even before her first visit, along with an idea for joining the search for vis­i­ble counter­parts of radio galaxies and radio-­quiet quasars.52 Before considering her proposal, Babcock wanted to see a status report on the O-­B star program a­ fter her December observing run. As for the other parts of her proposal, she needed to discuss possibilities with Sandage to avoid duplication of effort. The Caltech p ­ eople already had in hand substantial observing plans with similar objectives.53 Over the next few months, she talked to Sandage and thought about the huge amount of work she was undertaking. Fi­nally she told Babcock, in May 1966, “I have de­cided to defer my request for observing time this year. It is clear that the plates from last year contain so much information that it is more valuable to spend time to identify the blue stars and to obtain spectra of them, than to collect more plates.”54 In fact, her new ave­nues of research kept her so busy that no results from the plates taken for her O-­B star program appeared in print for a further five years. Eventually, two finding lists ­were published in 1971 and 1974.55 An application submitted by Kent and Vera for guest investigator time on the 200-­inch had been rejected, too. Babcock had turned down their proposal on November 5, 1965, suggesting that they instead undertake to obtain redshifts of quasars in collaboration with the observatory staff. Kent was particularly incensed by this, as the initial suggestion that they should apply for the observing time had come from Babcock when, back in May, he had proposed the temporary installation of the DTM spectrograph on the 200-­inch. Kent and Vera had responded positively to this tempting invitation even though they already had a heavy work program. Now, Babcock clearly expected them to go ahead with the installation without the incentive of being able to use the setup for their own observations. Kent’s immediate reaction was to draft a scathing four-­page reply to Babcock, a masterpiece

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of thinly veiled sarcasm underlining how ­little, in Kent’s view, Babcock knew about what would be involved in taking the spectrograph to Palomar, operating it successfully at the Cassegrain focus of the telescope, and reducing the observations.56 Yes, they would welcome collaboration, Kent wrote, “since we have our hands full right now trying to complete ac­cep­tance testing of some $50,000 worth of new image tubes, building half a dozen new systems to give away in the next c­ ouple of months, working out a sound observing program for the infra-­red system that operates fairly efficiently between 1 and 1.15 microns, and designing a mechanical mount for Dr. Bowen’s latest Cassegrain Schmidt camera . . . ​in addition to trying to untangle the previously unobserved lines in the spectrograms of QSOs from our last observing run.” It seemed to Kent that Babcock and his staff wanted to benefit from the advantages of the DTM spectrograph with no regard for the hard l­ abor that would fall on him and Vera to do the detailed planning, take the spectrograph to Palomar, and install it on the 200-­inch. Kent went on to offer ideas for how the collaboration could be made to work, in the pro­cess making the w ­ hole arrangement sound ridicu­lous, and knowing that his unrealistic suggestions would never be acceptable. Perhaps they could start right away, he ventured, by having Sandage come to DTM to help make the finding charts. At DTM they had the essential tool for the job, a Palomar Atlas, in their office—­which Sandage did not have. Kent knew ­there was no chance at all of the busy Sandage traveling across the continent to perform such a routine task. This was a way of needling Babcock for what Kent saw as a failure to recognize the kinds of reciprocal f­ avors required for amicable collaboration. Kent also reminded Babcock that he and Vera had requested a copy of a list of suspect objects Sandage had prepared for publication, but that their request “was apparently misplaced” since they had “not yet received anything.” Next he proposed that Sandage might help load the kit into a truck so it could be transported the 450 miles from Flagstaff to Palomar. It weighed hundreds of pounds. “Mrs. Rubin and I loaded the truck for our Kitt Peak run, but someone Sandage’s size sure would help in moving that spectrograph around,” he noted. “Also it would be fine if Sandage or someone would help me drive the truck over from Flagstaff to Palomar. . . . ​Mrs. Rubin is very good com­pany, but neither my wife nor her husband is likely to approve of our taking overnight trips together in that truck.”

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Then Ford mused on why Maarten Schmidt should take on some of the work, as well. “Our biggest operational prob­lem with the low dispersion image tube system is reaching in the spectrograph to focus the camera,” he reported. “In the new Cassegrain cage [on the 200-­inch] if I understand correctly, we may have as much as 12 or 16 inches clearance ­under the spectrograph in which to maneuver into position to make this focus adjustment. The collaboration of Maarten Schmidt in this phase would be welcome since it ­will require a thin astronomer to fit between the cage floor and the spectrograph bottom. It would be well for Maarten to become familiar with the spectrograph system from the bottom up since he undoubtedly w ­ ill have ­great interest in the spectrograms obtained with it.” Fi­nally, Kent rounded out the letter with what he and Vera saw as the most serious scientific impediment to the kind of “collaboration” Babcock was proposing. “­Here is the heart of the ­matter with re­spect to collaboration. The truth is that our spectrograms d ­ on’t look like unaided photographic spectrograms. They look fuzzy . . . ​but . . . ​we get comparable resolving power and are still better than 10 times faster. Now, to at least one of your staff astronomers, a fuzzy plate is a fuzzy plate and hence suspect—­regardless of how much information is contained on it.” Kent then explained that he and Vera had adapted the optics of their mea­ sur­ing machine to suit the image-­tube spectrograms, making the plates, Vera said, “a joy to mea­sure.” He was blunt at this point in the letter: “Now it would be very disappointing to all concerned if the 200-­inch DTM spectrograph plates turned out to be very difficult or impossible to mea­sure on the engines in Pasadena [where Caltech was located] as has been the case with very dif­fer­ent kinds of spectrograms from the 100-­inch in the past few years. Basically it was this past history that prompted our initial suggestion for us to have prime responsibility for the initial observing sessions. However, we now are happy to collaborate in the mea­sure­ment of plates which we obtain jointly with members of your staff.” Kent offered to provide on permanent loan the lens system needed to modify a mea­sur­ing engine at Pasadena to suit the image tube spectrograms. Palomar could keep an image tube, too, but Kent would reclaim the spectrograph itself when it was not actually in use on the 200-­inch. This final offer in the letter appears to be sincerely made but we ­don’t know w ­ hether the letter was ever sent in that form, or at all. The document in Vera’s files is headed “first draft.” We do know that the collabora-

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tion never happened. But ­whether sent or not, the letter is a clear indication of a lack of trust and cooperation between some of the Palomar and Caltech researchers and the DTM astronomers. Just a few weeks ­later, however, Allan Sandage sent Vera a cheery, handwritten message with finding charts for five pos­si­ble quasi-­stellar galaxies that he had been unable to observe at Palomar ­because of bad weather. Also conveying some sense of urgency, he ended his letter with “Call me collect if anything exciting comes up.”57 Vera’s first twelve months or so at DTM very much set the pattern for the rest of her active ­career. DTM’s annual report for 1965–1966 rec­ords that she and Kent spent a total of thirty-­five nights at Lowell and Kitt Peak.58 Observing was at the heart of what she did and remained so for over thirty years. Her life revolved around when she was allocated telescope time. Typically, she would make four or five trips ­every year, for runs of between two and five nights. Peter Boyce recalled that he never came across an astronomer who worked as hard as Vera. She would fill any waking time when she was not actually at the telescope with tasks such as mea­sur­ing plates. Above all, she was concerned that anything quantitative she mea­sured would be utterly reliable, and her attention to detail was truly impressive.59 Observing was physically and mentally demanding, but Vera was never happier than when she was working at a telescope. Reminiscing in her mid-­ sixties, she recalled what it was like for her in her early years. “Even with a fast image-­tube spectrograph and photographic plates, exposure times w ­ ere long. Often, I would split the cold 12-­hour night into two 6-­hour exposures, my eye at the guiding eyepiece throughout the night. . . . ​­Because we feared light leaks within the spectrograph, we observed in total darkness. My first view of the modern world of observing came one eve­ning when Roger Lynds offered me an automatic guider for the night, and on the next morning I detected individual features of unusual clarity on the galaxy spectra. This from an observer who prided herself on her guiding ability!” 60 In 1971, she observed for the first time in the southern hemi­sphere, at the Cerro Tololo Inter-­A merican Observatory in Chile. While waiting for Bob to join her a­ fter her observing run, she wrote an evocative description of a night at the telescope, typical of what her experiences as an observer would have been like around that time. This private note remained in her desk ­until she included it in her book Bright Galaxies, Dark M ­ atters in 1997. Arduous as the experience of observing was, it was always magical for Vera. She wrote

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about it as if she wanted to capture that magic in her own words for all time and keep it with her as a reminder.61 The piece begins by describing a bus journey across three hundred miles, from Santiago to the town of La Serena and from t­ here, inland and up to the observatory atop Cerro Tololo. As they draw nearer, “occasional views of the distant telescopes are connected by the colorful shadings in the mineral-­rich mountains.” Then she writes: For the astronomer, the night begins with an early supper, for by 5:30 pm I can be at the telescope, setting up the equipment for the night’s program. The sun w ­ ill set within the hour, and w ­ ill rise 12 hours l­ater. During that time of darkness, each minute w ­ ill be precious, and I w ­ ill be aware that I am racing the sun. I arrive with a motley collection: heavy socks, underwear, flashlight, thermos. Closed during the day to keep out the warm air, the telescope dome is now opened to allow the telescope to reach the temperature of the cool night air. It is already 40° in the never-­heated dome, and the lights are out, as they ­w ill be all night to protect the dark adaptation of the observers. I am joined in the dome by a Chilean night assistant, one of a group of bright, enthusiastic, nearly bilingual aides, who operate the telescope and help with guiding during the long exposures, if the observer wishes. . . . As darkness falls, the telescope is set on a bright star for focusing and for making small corrections to the coordinates as read on the barely lit console. The rest of the night, I w ­ ill be photographing on glass plates spectra of galaxies so distant that they appear small and faint and are difficult to detect against the dark night sky. The telescope is set from very accurate positions; a photo­graph of that sky region taken ­earlier is examined ­under a dim red light, and the view through the telescope is searched to find the object. To­ night I am attempting to get velocities of galaxies in order to study details of the expansion of the universe. For the first exposure, I take about 15 minutes to locate the faint galaxy and center it exactly, and then locate a nearby bright star on which I can guide the telescope. During the next 90 minutes I stand at the telescope, too intent to sit, keeping the crosswires fixed exactly on the bright star in the viewing scope. About once e­ very minute I correct slightly as the star starts to drift from the crosswires. At Kitt Peak National Observatory outside of Tucson, Arizona, the ­sister observatory to Cerro Tololo, an electronic device guides the telescope during the exposure, but such equipment is not yet available in Chile. I enjoy both modes of observing. Guiding is fun, and standing in the cold dome throughout the night makes the science extremely personal. Es-

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pecially during my long six-­hour exposures of Andromeda a few years ­earlier, I would sit as I guided on the nucleus of that galaxy and won­der if someone ­there was sitting in a cold dome looking at our Milky Way. Often I wished we could exchange views. The 12-­hour night is used up with six exposures. I vary the times slightly as the brightness of the object requires, and modify the proposed program slightly as the science requires. For one exposure, a bright star in the field was suspected of being a supernova, so an exposure was taken of the star. Only a star, no supernova. The night is cold, the work is tedious, and the long hours pass slowly. My vigil is interrupted occasionally when I leave the dome to develop a plate, also in total darkness, to confirm that all is ­going well. During t­ hese minutes, the night assistant takes over the guiding. Morning brings the end of observing for the night, and brings the sun, and the spectacular view of the coastal fogs filling in all the valleys between the high peaks. With the sun my circadian rhythm is reset and I am wide awake, too wide awake to sleep and too curious to leave the night’s plates undeveloped, so I walk down to the dark room. Even though the dark reminds me of my tired body, I know that it is futile to attempt to sleep while wondering what is captured on the photographic plates. So I remind myself of my advice to my postdocs, “Observational astronomy is still an art, the art of making as few ­mistakes as pos­si­ble.”

During the course of 1966, Rubin and Ford began to take stock of what they had been ­doing since Vera’s arrival and to consider their ­future direction. Ford continued to work on technical developments and improvements to the DTM spectrograph, and to assist observatories around the world with integrating image tubes into their own instruments. He was less directly involved with the image tube committee, which was engaged in deciding which observatories should get the tubes. Merle Tuve had retired from the directorship and Vera had no more concerns about proving the value of image tubes to the rest of the astronomical world. Now the primary objective for DTM’s small optical astronomy team was to create a purposeful research program to take full advantage of the capabilities of their image tube spectrograph. In March 1966, Vera described their observations of fifteen quasi-­stellar objects at the 121st meeting of the American Astronomical Society in Hampton, ­Virginia, and in July she gave a series of lectures at the summer school in Les Houches where, seven years e­ arlier, she had accompanied Bob and unofficially sat in on sessions. Before ­going to France, Vera had ­stopped

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off in ­England and talked to the radio astronomers at Cambridge University about identifying objects in their most recent 4C cata­log of radio sources, the first part of which had been published in 1965.62 Vera and Kent ­were thinking seriously, however, about ­whether they wanted to continue their journey aboard the quasar bandwagon. As Martin McCarthy planned a next visit at the end of the year, Vera wrote him in September, “We are all looking forward to your return and perhaps can offer you slightly more calm than we did last year. The quasi-­stellar objects are occupying less and less of our time. . . . ​We are giving some thought to the entire observing program.” 63 Kent and Vera ­were experiencing similar emotions. “I would have to say that we ­were both discouraged by the competitive aspects of d ­ oing redshifts,” 64 Kent recalled years ­later. Vera’s memory matched that: “I found it personally very distasteful. I just did not like the pressure of other astronomers calling and asking me if I had observed this and if I knew what the redshift was . . . ​I just de­cided that w ­ asn’t the way I wanted to do astronomy.” It was an exciting time, but Vera was not comfortable with the very rapid pace of the competition.65,66 They experimented with taking spectra of an assortment of galaxies, and targets of opportunity such as supernovae and recently discovered X-­ray stars and pulsars. But Vera had formed a plan for a systematic study that was well-­ suited to the telescopes at their disposal, would exploit the advantages of the DTM spectrograph, and could build on the experience they had gained of targeting faint objects. It would hark back to her long-­standing interests in learning how galaxies rotate and comparing optical and radio observations. Best of all, they w ­ ere very unlikely to be in competition with anyone ­else. It was an in­ter­est­ing proj­ect they could work on at their own pace without feeling pressure. The object Vera had in mind was the Andromeda Galaxy, also known as M31—­the nearest g­ reat spiral galaxy to the Milky Way, even vis­i­ble to the naked eye as a faint, misty patch. In M31, as in the Milky Way, hundreds of clouds of glowing hydrogen gas, the birthplaces of new stars, are strung out along spiral arms. Although individual stars at that distance ­were too faint for taking spectra, ­these g­ reat luminous clouds ­were within the grasp of the DTM spectrograph. They ­were the beacons of light by which the internal motions of M31 could be sampled all across the galaxy. Before his death in 1960, Walter Baade had identified 688 of them on photo­graphs of M31 he secured with the 100-­inch telescope

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at Mount Wilson, and he had mea­sured their positions on the plates. ­A fter Baade died, his former student, Halton Arp, completed the cata­log. It was published in 1964 “for reference and for use of f­ uture investigators,” as Arp put it.67 If Vera had read the May 15, 1964, issue of The Astrophysical Journal, she must have forgotten about this par­tic­u­lar paper. She and Kent spent one bitterly cold and frustrating night at the US Naval Observatory near Flagstaff, Arizona, trying unsuccessfully to work out how to identify and determine the positions of emission nebulae—­H II regions, as astronomers call them— in M31. (H II, pronounced “H-­t wo,” is an abbreviation for ionized atoms of hydrogen, which are responsible for much of the light emitted by glowing nebulae.) Fortunately, the next day, a colleague pointed out that Baade had already done that work for them. Baade’s legacy was “a remarkable gift, truly coming from heaven!” 68 In late 1967, Kent and Vera secured their first observations: spectra of four of the glowing clouds listed by Baade and Arp. With t­ hese early observations, Vera and Kent successfully deduced velocities that agreed well with radio observations made by DTM radio astronomers.69 They had proved the study was feasible. Now they had begun, M31—­the Andromeda Galaxy—­would occupy Vera and Kent for some time to come.

CHAPTER 8

ADVENTURES IN ANDROMEDA

I

n 2011, reflecting at the age of eighty-­three on a distinguished professional ­career spanning more than fifty years, Vera described the years between 1960 and 1970 as being “a remarkable period in our lives.” In that de­cade, she and Bob completed their f­ amily and she made a momentous move from Georgetown to Car­ne­gie. The same years saw the flowering of her exceptional talent for observing, reducing, and analyzing her own data on the dynamics of galaxies.1 At the end of the de­cade, she and Kent Ford published a landmark paper on the Andromeda Galaxy, M31. For astronomy more generally, it was a period of groundbreaking change. ­There was palpable excitement at international meetings and symposia about the latest discoveries. To go to t­ hese gatherings was to be confronted with mind-­bending questions: Do you think active galaxies are powered by supermassive black holes? Do you know how the missing mass prob­lem might be resolved? Do you believe in dark ­matter? Tackling such challenges had become a priority for theoretical and observational cosmologists alike. Vera Rubin, as an observer, was a pioneer in making high-­precision mea­sure­ments of motion in the extragalactic universe. Her data on the rotation of galaxies would in due course both stimulate and constrain theorists. To begin with, though, somewhat against the trend, she had set her sights no farther than the large spiral galaxy in Andromeda, M31, just “next door” in astronomical terms. Our own Milky Way, by then understood to be a large spiral galaxy, too, was often compared with M31 in which many stars and glowing nebulae could be picked out individually. For a ­whole host of reasons, it represented a tempting target for the capabilities of the DTM image tube spectrograph. One ­thing that would have drawn Vera to M31 was her long-­standing interest in comparing radio and optical studies to understand the dynamics of galaxies. The prospect of research along ­these lines had attracted her to

Fig. 8.1 Image of the Andromeda Galaxy (M31) taken with a 12.5-­inch Ritchey-­Chrétien telescope by amateur astronomer Robert Gendler. (© 2002 R. Gendler)

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DTM in the first place, even before she knew about the new opportunities the image tube spectrograph would open up. Vera was still at Georgetown in 1963, when DTM radio astronomer Bernie Burke, together with Kenneth Turner and Merle Tuve, observed radio emission from the neutral hydrogen gas in M31 and in several other nearby galaxies, with the newly commissioned 300-­foot transit telescope of the National Radio Astronomy Observatory (NRAO) at Green Bank, West V ­ irginia. The fledgling radio astronomy group at DTM had designed a spectrometer to use with the new telescope for observing the velocity and density of neutral hydrogen in the Milky Way and the nearest spiral galaxies. For seven weeks (from December 5, 1962, to January 24, 1963) the Green Bank big dish was devoted exclusively to observations with the Car­ne­gie spectrograph. More observations followed in the summer of 1964. Burke and his collaborators presented their results on M31 at length, including a rotation curve, in the Car­ne­gie Year Book for 1963– 1964. They conceded, however, that the resolution of their observations was not good enough to plot a rotation curve directly. Instead, they compared their a­ ctual mea­sure­ments with the predictions of vari­ous theoretical possibilities to see which worked best.2 In fact, they ­were not the first radio astronomers to publish a rotation curve for M31. In 1956–1957, the Andromeda Galaxy had been among the earliest targets of the new 24-­meter dish at Dwingeloo Radio Observatory in the Netherlands. The Dutch team had found that the rotation velocity of hydrogen in M31 peaked at 280 km / s and then declined ­gently to 225 km / s at 26 kpc (26 kiloparsecs, equivalent to about 85,000 light years) away from the center of the galaxy.3,4 During 1963–1964, the 300-­foot telescope at Green Bank was used again to observe M31, this time by NRAO radio astronomer Morton Roberts, who made a high-­resolution survey. He had the benefit of an upgraded receiver and more observing time, and collected more detailed and thorough data than the DTM radio group had—­extending out to about 30 kpc beyond the center of the galaxy. ­There was no sign of the rotation speed falling.5 It was the same apparent anomaly that Vera had found for the Milky Way when she and her students plotted its rotation curve in 1962 (as described in Chapter 6). They noted that it was “flat, and does not decrease as is expected for Keplerian orbits.” 6 Roberts, too, in the case of M31, commented “how poor our assumption of Keplerian motion was, even at distances of about 20 kpc from the nucleus.”

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Vera would have been well aware of Roberts’s results. She and Mort w ­ ere friends and he kept her informed about his work on M31. Vera was also cognizant of the fact that, for each data point, the 10-­second-­of-­arc beam of the radio telescope encompassed a relatively large patch of sky, with a dia­ meter of about 8 ­percent of the ­whole long axis of the galaxy. By comparison, optical observations pinpointed much smaller regions. Vera thought that this would make her data more convincing than ­those the radio astronomers had published. Not only that, ­there was a discrepancy between the radio results and the most recent optical mea­sure­ments of M31’s rotation, published by Nicholas Mayall back in 1951.7 The Dutch radio astronomers had commented on that discrepancy, too, in their 1957 paper. Mayall had, however, admitted to Mort Roberts that his data ­was not very precise.8 ­There was a real question of ­whether radio and optical mea­sure­ments might genuinely yield dif­fer­ent numbers, and Roberts commented in his paper that “additional optical observations are obviously necessary.” Was he thinking of Vera? With the image tube spectrograph, it was certainly a proj­ect that Vera and Kent Ford could contemplate. Vera had already acquired know-­how useful for the task she now had in mind. While working for the Burbidges in 1963 to 1964, she had learned much about the rotation curves of galaxies. “Only l­ater would I understand what an exceptional introduction ­these activities had on my ­future ­career,” she would reflect, when looking back over her life in 2011.9 When Vera arrived at La Jolla, the Burbidges had many unpro­cessed spectra of nearby galaxies, which they had taken with the 82-­inch reflector at the McDonald Observatory since commencing their campaign to obtain rotation curves for about thirty spiral and irregular galaxies back in 1959. Their spectrograph was well suited to analyzing the light emitted by hydrogen and nitrogen in the interstellar gas pervading the brighter central regions of nearby galaxies. They positioned the long slit of the spectrograph across a galaxy for one exposure, then repeated the exercise with the slit at dif­fer­ent orientations. Margaret set Vera to work on mea­sur­ing the red or blue shifts of the light at dif­fer­ent points along the extended width of the chosen spectrum lines. Each mea­sure­ment along a line corresponded to a dif­fer­ent distance from the center of the galaxy. It was a demanding task, for which Vera used a Mann two-­dimensional mea­sur­ing engine. Theoretically, the engine was capable of mea­sur­ing positions on the photographic plates with an

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accuracy of 0.001 mm. In practice, centering the microscope on the fuzzy lines required considerable skill. Although Vera had mea­sured lines in the solar spectrum at Georgetown, working with t­ hese galaxy spectra required a dif­fer­ent technique. Vera also became familiar with the procedures for converting the raw data from the mea­sur­ing engine into a rotation curve and then using a rotation curve to deduce how m ­ atter is distributed throughout a galaxy to the farthest limit of the observations. The mathe­matics they used had been developed by Kevin Prendergast, a colleague of the Burbidges from the five years they had spent at Yerkes Observatory. All of this, Vera recollected in l­ater years, “was an invaluable experience for me.”10 At this point, it is worth reviewing how astronomers had gradually added to their knowledge of M31 before Vera and Kent Ford took up the challenge. Vera herself was very interested in the history of galaxy spectroscopy and made it the subject of a prize lecture she gave to the American Astronomical Society in 1995. As she commented then, “One hundred years ago, no one knew what a galaxy was.”11 William and Caroline Herschel carried out the first major census of what astronomers in ­England described as “white nebulae” in the late eigh­teenth c­ entury. William speculated that the attractive force of gravity molded their structure. Neither the Herschels, however, nor Lord Rosse, who possessed the largest telescope in the world in the 1840s, could produce convincing evidence that t­ hese white nebulae lay far beyond the Milky Way. William Huggins (1824–1910), British pioneer of astronomical spectroscopy, cast an inquisitive eye on the brightest part of the g­ reat nebula in Andromeda in 1864. He came to a preliminary conclusion that white nebulae ­were not aggregations of stars.12 So what did astronomers imagine they ­were? As late as 1890, Irish astronomer and historian Agnes Mary Clerke airily dismissed as nonsense the notion that nebulae w ­ ere “island universes,” the speculative concept offered by the Prus­sian Enlightenment phi­los­o­pher ­Immanuel Kant in 1755.13 New information about the nature of the nebulae was unexpectedly revealed at the University of California’s Lick Observatory, which opened in 1888 as the world’s first permanently occupied mountain observatory. With dark skies and few clouds, this remote site was far superior to the large cities that ­housed the historic observatories of Eu­rope. James Keeler (1857–1900), the first director of Lick, established the importance of photographic imaging with large reflecting telescopes (in his case, the 36-­inch Crossley re-

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flector) for examining the nebulae. ­A fter his untimely death at the age of forty-­t wo, Lick Observatory published a monumental atlas containing his photo­graphs of nebulae and star clusters. In its preface, Keeler is credited with suggesting that ­there ­were hundreds of thousands of nebulae that could be reached by the Crossley reflector, and that “Most of ­these nebulae have a spiral structure.”14 Julius Scheiner (1858–1913), an experienced astrophysical spectroscopist with a penchant for experimentation, secured the first successful photographic spectrum of M31 in January 1899 at the Royal Astrophysical Observatory in Potsdam. He acquired a game-­changing spectrum with an exposure of seven and a half hours, using a reflector and a spectrograph specially constructed to his own design. His “comparison of this spectrum with a solar spectrum taken with the same apparatus” revealed “surprising agreement between the two.” He went on to reason that the nucleus of the Andromeda Nebula was composed of stars and that the interstellar space “is not appreciably occupied by gaseous m ­ atter.” In his opinion, “the previous suspicion that the spiral nebulae are star clusters is now raised to a certainty.”15 Scheiner never published his spectrum, but Vera found his insight into the fact that M31 is an assemblage of stars so striking that she “repeatedly asked astronomers from the Potsdam Observatory to attempt to locate it.”16 Hans Oleak wrote to her on September 7, 1987, thanking her for encouraging him to search for “this historically impor­tant observation.” He had found the plate, an incredible stroke of luck a­ fter two world wars and numerous upheavals in Eastern Eu­rope. He noted that “The spectrum is so extremely weak that by visual observation no features are distinctly recognizable,” which was hardly surprising given its age. ­A fter tracing it, he was pleased to tell Vera that inspecting “the historic spectrum with modern technology” had confirmed the fundamental conclusions drawn by Scheiner eighty-­eight years ­earlier.17 Percival Lowell (1855–1916), a businessman whose En­glish ancestors from Bristol had arrived in Boston in 1639, set up an observatory in Flagstaff in 1894, and equipped it with a 24-­inch refracting telescope to satisfy his fascination with the planet Mars. In 1901, hoping to discover how planetary systems form, he added a new spectrograph to the telescope and hired an astronomy gradu­ate from Chicago, Vesto Slipher, to run the observing program on his behalf. Slipher’s g­ reat expertise at recording spectra photographically duly impressed Lowell, who encouraged him to probe the enigmatic spiral

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nebulae. Could they be ­future planetary systems in the making? On September 17, 1912, Slipher made the astonishing historic discovery that light from M31 is shifted noticeably ­toward the blue end of the spectrum, meaning that it is approaching the Milky Way at a considerable velocity.18 Responding with alacrity, Lowell shipped his personal microscope out to Flagstaff so that Slipher could examine the spectrum in more detail. During January 1913, Slipher secured four new plates and worked meticulously on reducing the data, taking ­great care to control sources of error. The result astounded Slipher and Lowell: Andromeda is hurtling ­toward our home galaxy at 300 kilo­meters per second! Both w ­ ere taken aback: this was ten times higher than the average speed of stars relative to the Sun in our part of the Milky Way. Slipher’s competitors in California commanded a superior 36-­inch telescope and their reaction to the startling news from Arizona was marked ­skepticism. Lick director W. W. Campbell penned a letter contesting the claim: “your high velocity for the Andromeda nebula is surprising in the extreme. . . . ​the error of your radial velocity mea­sure­ment may be pretty large, I hope you have more than one result for the velocity, and no doubt you have.”19 Slipher was not perturbed. He applied himself diligently in the 1913–1914 observing season, obtaining “numerous spectrograms of nebulae,” including “a few with indications of [rotation], among them t­ hose of the ­great Andromeda Nebula,” where he had aligned the slit through which light entered the spectrograph along the major axis of the elliptical shape he could see. He described “the discovery of the rotation of this nebula” as the opening of a new field of investigation.20 Half a c­ entury ­later, Vera and Kent Ford would arrive at the Lowell Observatory to take forward this field of investigation with the innovative image tube spectrograph. Slipher’s discovery that M31 is spinning around its center ushered in a de­ cade during which discoveries about the dynamical properties of nebulae came at a brisk rate, thanks to significant improvements to instruments as well as larger telescopes. In August, September, and October 1916, Francis G. Pease (1881–1938), spectroscopist at Mount Wilson, used the 60-­inch reflector ­there for a single exposure of eighty-­four hours, on this occasion aligning the slit of the spectrograph along the minor axis. It beautifully confirmed the ­wholesale rotation of the Andromeda Nebula.21 Sixty years l­ater, Vera pronounced Pease’s achievement to have been “heroic.”22 The following year he made two dif­fer­ent sixty-­nine-­hour exposures along the major axis, which

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earned him further praise from Vera. She admired his meticulous approach to observing, and commented approvingly that “the resulting values are of sufficiently high accuracy to warrant serious scientific consideration t­ oday.”23 Within another three or four years, a handful of astronomers had estimated the distance to M31 by adopting the hypothesis that the nebula contains stars. The publication of Pease’s rotation curve prompted Ernst Öpik (1893–1985) of the University of Tartu, Estonia, to think of an ingenious method. In 1922, he worked out the distance at which Andromeda would appear to have the same mass-­to-­light ratio as our Galaxy, an approach that echoed what Scheiner had noted about the similarities between the Andromeda Nebula and the Milky Way.24 Öpik arrived at a distance of 450 kpc (1.5 million light years), which is considerably greater than the figure of 285 kpc (900,000 light years) that Hubble and o­ thers would use from 1926 ­until the early 1950s and closer to the distance of around 770 kpc (2.5 million light years) ­adopted ­today.25 Furthermore, Öpik emphasized that the coincidence of distance estimates from in­de­pen­dent sources “increases the probability that this nebula is a stellar universe.”26 Rubin personally respected Öpik’s paper as “one of the most original papers of this ­century.”27 Edwin Hubble had turned his attention to the Andromeda Galaxy and M33 in the constellation Triangulum from the outset of his ­career, which began at Mount Wilson in 1919. The mighty 100-­inch telescope at Mount Wilson was at that time the largest telescope on Earth, and it required tedious manual guiding. Fortunately for Hubble, a night assistant, Milton L. Humason, carefully adjusted the aim of the telescope for hours at a time. The two men w ­ ere a well-­matched team: Hubble the pioneer of exciting science, and Humason the patient observer. Hubble’s greatest breakthrough was trumpeted on December 24, 1924, at the 33rd Meeting of the American Astronomical Society in Washington, DC: “­Under good observing conditions . . . ​the outer regions of [M31 and M33] are resolved.” A considerable number of the stars they could pick out individually w ­ ere very luminous variable stars of a type known as Cepheids. Their well-­known characteristics enabled Hubble to estimate that they ­were about 900,000 light years away, considered a stupendous distance in 1924. M31 and M33 ­were unquestionably extragalactic. Hubble had confirmed the “island universe” hypo­ thesis.28 Within another ten years, he had compiled the distances of enough galaxies to establish that they are the major components in the structure of the universe.

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The next move forward was achieved in 1939 by Horace Welcome Babcock, the ­future director of the Palomar and Mount Wilson observatories, but at that time only a doctoral student at the University of California, being advised by Nicholas Ulrich Mayall. Babcock’s PhD thesis addressed one of the most pressing prob­lems in extragalactic astronomy at the time: how to determine motion within galaxies. In princi­ple, it would enable astronomers to deduce both the total mass of a galaxy and the distribution of mass. Babcock hoped that such studies of many spirals would make it feasible to work out how they evolve. He had in mind theories about the formation of spiral arms. Mayall, who appreciated the intricacies of trying to fathom the dynamics of our own Milky Way system from within, suggested to his student that he tackle the nearest and brightest large galaxy, M31, for which a considerable body of knowledge had already accumulated. The extreme faintness of stars in M31 made observation of their individual spectra impossible. Instead, using the 36-­inch Crossley reflector at Lick Observatory, Babcock obtained spectrograms of small patches of the diffuse light emitted by the nuclear bulge of Andromeda at several dif­fer­ent positions, and of the light from five small “emission nebulosities” in the resolved portions of the spiral arms. The exposure times ranged from seven to twenty­t wo hours. His spectra showed, for the first time, large rotation speeds for gas far from the center of M31 where a decrease was expected, a phenomenon that would ­later be noted by Rubin and ­others. The speeds with which ­those five emission nebulae (H II regions) revolved around the center of the galaxy w ­ ere consistent with “a nearly constant velocity of the outer parts of M31,” which was “the opposite of the ‘planetary’ type of rotation believed to obtain in the outer parts of the [Milky Way] Galaxy.”29 Babcock’s findings implied that M31’s mass was on the order of one hundred billion solar masses, much larger than Hubble and ­others w ­ ere suggesting. Babcock was invited to make a pre­sen­ta­tion on his work at the dedication in 1939 of the 82-­inch telescope at the McDonald Observatory. No one had an explanation for his puzzling results, but he impressed many of the distinguished astronomers who ­were attending, including Jan Oort and Bertil Lindblad, both world-­renowned experts. Such was his impact at the time that, on the spot, he was offered a job on the staff of the Yerkes Observatory.30 ­Today, Horace Babcock’s pioneering observations of M31—­his sole venture into extragalactic astronomy—­can be regarded as a landmark in the

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detection of the discrepancy between the observed rotation curves of spiral galaxies and what would be expected on the basis of their light profiles.31 World War II and its aftermath interrupted many lines of astronomical research for over a de­c ade but, as mentioned e­ arlier, Babcock’s advisor, Mayall, took up the optical investigation into M31’s rotation again a­ fter the war. He reported in 1951 on the velocities he had derived from spectra of thirty-­two emission nebulae close to the major axis of M31, taken mostly with the Crossley reflector of the Lick Observatory, but all of them w ­ ere within 32 8 kpc of the nucleus. ­A fter this, no one made further optical observations of emission regions in M31 ­until 1967, when Rubin and Ford took their first tentative steps with the innovative image tube spectrograph attached to the Perkins telescope at Lowell Observatory, which had recently been upgraded with a new 72-­inch mirror. ­A fter finding in late 1967 that their initial results w ­ ere in “good agreement with the rotational velocities determined from the neutral hydrogen observations,” Vera designed a program to observe sixty-­seven selected H II regions spanning the galaxy, up to the farthest extent from the nucleus that their method would allow.33 ­These observations w ­ ere by no means easy. The H II regions ­were too faint to be vis­i­ble directly so the telescope had to be aimed blind, by calculating exactly where the target was in relation to a star in the telescope field of view that they could see and guide on. She prepared by poring over long-­exposure photo­graphs to select several stars she could possibly use as guides—­usually three per H II region. Then she carefully mea­sured their positions well before her arrival at the telescope, time being of the essence once observations w ­ ere underway. With the aid of the guide stars, Vera precisely positioned the telescope on her invisible targets, shivering in ambient temperatures well below freezing (Lowell Observatory is at an elevation of 2,210 meters). It was “a hard task in a cold dark dome with freezing fin­gers inside heavy gloves.” And it was utterly dark inside the dome. Even the luminous clock dial was covered on Vera’s instructions. While guiding the telescope by eye over many hours for a single exposure, often sixteen hours at a stretch, she found “the greenish glow of the M31 nucleus exhilarating and a ­little spooky.”34 Obtaining the spectra of emission regions in M31 at Lowell “was tedious and it required four hands.” Their first exposure (prob­ably on 4 September 1967) was not uneventful: a curious guest astronomer looked on in fascination.

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Fig. 8.2 Vera Rubin eyeing up a spectrum in the 1970s (date unknown). (DTM, Car­n e­gie Institution of Washington /  Charles H. Phillips)

On completion of the exposure the three went expectantly to the dark room. Within a few minutes they handled their first Andromeda spectrum. Vera and Kent ­were ecstatic and wanted to get back to the telescope without delay, so the guest volunteered to finish the developing. Vera recalls that, “When we returned with the second plate, we found that he had accidentally washed the first plate in hot w ­ ater rather than cold, completely washing off the emulsion. The plate was absolutely blank.” The guest was mortified, but Vera d ­ idn’t care a bean about the mishap: “I was so delighted that every­thing worked.” She was gleefully anticipating hundreds of exposures, and having ­great fun d ­ oing so.35 ­A fter that glitch with the first plate, Vera’s two sessions at Lowell in 1967 worked out just fine. “The surprises came very quickly,” she remembered. “By the end of the first night we w ­ ere puzzled by the shape of the rotation curve.” Why? B ­ ecause, even by just eyeing up the spectra as they w ­ ere taken, she could tell that the velocities ­were not decreasing with increasing distance from the center. Vera immediately grappled with the wild thought that “­there must be some mechanism for speeding up stars that moved too slowly or slowing down stars that moved too fast.”36 In September they obtained good spectra of thirteen emission regions, then followed that success with a spectacular six-­night observing run on 6–11 October that garnered a bumper harvest of forty-­six spectra. Th ­ ose two runs

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Fig. 8.3 Vera Rubin, sometime in the 1970s, standing at the DTM image tube spectrograph mounted on the 84-­inch (2.1-­m eter) telescope at Kitt Peak National Observatory (date unknown). (DTM, Car­n e­gie Institution of Washington)

had sandwiched a quick dash to the Kitt Peak National Observatory (KPNO), where Director Nicholas Mayall had granted Vera three nights, 2–4 October, on the newly-­completed 2.1-­meter (84-­inch) telescope. For that trip, she and Kent loaded the somewhat cumbersome DTM spectrograph into a truck. They merrily bumped along for five hours, down the 260 miles of road from Flagstaff to Tucson (­there was no interstate highway), and from t­ here headed west for the 50-­mile drive up to KPNO (elevation 2100 m) in southern Arizona. That session added another fourteen spectra of emission regions to their growing collection. At the end of the 1967 season Vera had seventy-­three plates waiting for her to begin the data reduction pro­cess. Andromeda would not be vis­i­ble in the night sky again u ­ ntil the following fall, but she was almost halfway to her target: to minimize errors she hoped to secure a minimum of two plates of each H II region, taken in dif­fer­ent seasons. In the 1968 season, her rec­ords place her at Lowell from 15 to 22 September and from 19 to 25 October, in sessions that w ­ ere equally as productive as the previous year’s, although she did not succeed in capturing all H II regions

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on her list twice. Nevertheless, she was content that what she had was good enough. She was almost ready to plot a rotation curve, but not quite ­because she needed something e­ lse. Although Guido Münch (Palomar Observatory) and Merle Walker (Lick Observatory) had published good data in 1960 for the rotation rates of the nuclear region, which Vera could simply have cited, she preferred to complete a comprehensive rotation curve herself.37,38 To do this, she needed spectra from the innermost regions of M31 and so, truck, DTM spectrograph, Vera and Kent careered down to Tucson, en route for KPNO once more, where on 18–20 November 1968, they patiently guided the 84-­inch reflector for three nights. Her reward was nine spectra of diffuse light emitted near the bright nucleus. And with t­ hose, she had all she needed. It had taken Vera and Kent two years to complete the observations necessary for the attack on the dynamics of M31. With her carefully curated spectrograms, which ­were a major advance on Mayall’s observations at Lick in 1951, she would now determine radial velocities much farther from the center than anyone ­else had ever managed with optical observations. Her data set extended between about 100 parsecs and 24 kpc (350 and 80,000 light years) from the heart of the galaxy. We should mention h ­ ere that ­these, and all other distances within M31 we quote are ­those Rubin and Ford calculated from the angular distances on the sky they actually mea­sured in minutes of arc, with the assumption that the galaxy is 690 kpc away. T ­ oday, the distance of M31 is estimated to be somewhat larger—­about 770 kpc, which means that, if Rubin and Ford ­were writing now, they would make all the distances within M31 about 10 percent greater. Vera invariably took the greatest care when reducing her data. Finding radial velocities involved her calculating, as precisely as pos­si­ble, the wavelengths of bright lines featuring in the spectra. This was done by mea­sur­ing their positions relative to lines in a standard comparison spectrum, exposed on the same plate. The glass plate went into a mea­sur­ing engine that incorporated a microscope for viewing the plate, very accurate screws that moved the plate u ­ nder the microscope when they are turned, and finely engraved wheels from which to read how far the plate moved. Vera translated the amount by which lines are shifted from their standard laboratory wavelengths, ­toward ­either the blue end or the red end of the spectrum, into radial velocities. Then she had to take off the motion due to Earth’s spin and its revolution around the Sun, and allow for the tilt of M31 to calculate orbital speeds.

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Fig. 8.4 Vera Rubin mea­sur­ing photographic plates at DTM in 1972. (DTM, Car­n e­gie Institution of Washington)

Vera’s end product was a ­table listing for each H II region the distance from the center of M31 and its velocity along its orbit, presumed to be circular. She then plotted ­t he data graphically as a series of points, bracketed by the extent of uncertainty around the ­adopted value. Distance from the center was represented along the horizontal axis, while the vertical axis was for orbital velocity about the galaxy center. The next task was to draw a curve through the data points. She did not do this freehand but worked out mathematical formulas for the curve that best fitted the data. ­There was more than one way of approaching this, so she came up with a set of fourteen dif­fer­ent curves—­but, in practice, they did not differ by very much.39 Vera also continued to satisfy herself that her results ­were consistent with the velocities mea­sured a few years e­ arlier by her radio astronomer colleagues.40 Now in possession of a rotation curve, Vera could move on to calculate M31’s total mass, and how that mass is distributed through the galaxy. To explain the mathematical pro­cess, it is helpful to pause and consider two impor­tant footnotes from the long history of studying motion in the cosmos. As we encountered in Chapter 6, in connection with Vera’s work on the

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rotation curve of the Milky Way, in 1609 and 1619, Johannes Kepler published his three laws describing the motions of the five naked-­eye planets as he observed them. He did not, however, offer any deeper or more general explanation. That had to wait for Isaac Newton, who in 1687 promulgated his law of universal gravitation: objects attract each other with a force directly proportional to the product of their masses and inversely proportional to the square of the distance separating them. Newton’s law of gravitation, when applied to the solar system, leads straight to Kepler’s laws of planetary motion but, in the case of the Sun and planets, the calculation is ­simple b­ ecause each body can be treated as if its mass is concentrated at its own center. The relatively small planet-­to-­planet attractions can be ignored for the broad-­brush picture ­because the Sun contains 99.8 ­percent of all the mass in the solar system. But moving beyond the solar system, how can we apply Newton’s law when the mass is distributed more evenly through space—­for example, in the disk of a galaxy? Clearly the prob­lem is more complex, with countless moving parts, and computing a myriad of gravitational attractions between the stars, one by one, would be an im­mense task. Newton cracked one impor­tant aspect of this with his “shell theorem.” He proved that the gravitational attraction of a sphere on something outside it is the same as if the sphere’s entire mass ­were concentrated at its center. Furthermore, the strength of the gravitational field at any location within a sphere is due solely to the mass within the same distance from the center as the chosen location: the contributions of every­thing farther away, taken as a w ­ hole, come to zero. This power­ful theorem means that it is pos­si­ble to uncover how mass is distributed in a galaxy as far out from the center as you know its rotation curve. And that’s what Vera did next. M31 does not resemble a sphere, and Vera did her calculations on the basis that it is disk-­shaped with a bulge in the m ­ iddle. Extracting the information about the mass involved considerable amounts of computation. This Vera did on an IBM 1130 computer, which had been introduced in 1965 for the scientific and engineering market. Typically, the IBM 1130 came with a 1 Mb hard disk, 32k of magnetic core memory, input via Fortran programs submitted on punched cards, and an IBM line printer for output. Vera often consulted Bob about mathematical analy­sis and it seems likely she did so in this case. Her published paper acknowledges him among the five colleagues she wished to thank “for valuable conversations.”

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In December 1968, Vera presented her results on rotational velocities in M31 to the 128th Meeting of the American Astronomical Society, convened in Austin, Texas. By this stage she was certain that the rotation curve of M31 far from its nucleus was flat, t­here being no sign whatsoever of the radial velocities dipping down with distance far from the center: t­hese w ­ ere not “Keplerian velocities.” For many in the audience, that was very surprising news, despite similar findings already coming from radio astronomers. “Most astronomers in the mid-­fi fties grew up believing that disk galaxies had ­Keplerian velocities at moderate distances,” she ­later recalled. She thought the legacy of Slipher might have been partly to blame.41 Slipher had begun his observational ­c areer working on planets and he turned to spiral nebulae in the belief that they could be solar systems in the making. Not only that, the early spectral observations w ­ ere restricted by the instruments available to the bright nuclear regions. By mid-­century, ­there ­were a handful of such ­limited rotation curves and astronomers’ perceptions ­were that t­ hese curves had the expected Keplerian character. On the basis of eight rotation curves, de Vaucouleurs concluded in 1959 that t­ here was a radius “beyond which the rotational velocity decreases with increasing distance to the center and tends asymptotically t­oward Kepler’s third law.” 42 They ­were kidding themselves: with twenty-­t wenty hindsight it is easy for us to see that only optimists inclined to see what they ­were looking for could interpret ­these rotation curves as “Keplerian,” given their ­limited extent and scattered data points. In March 1969, when Sky and Telescope reported on the Austin AAS meeting, Vera’s talk topped its coverage.43 The magazine proclaimed that her rotation curve of the Andromeda Galaxy “agrees well with the rotations determined from 21 cm radio observations by Morton S. Roberts at the NRAO.” 44 At the same AAS meeting, Vera would no doubt have had an opportunity to debate the latest news on rotation curves with Gérard de Vaucouleurs; he and his wife, Antoinette, ­were showcasing their recent results on nine spiral galaxies.45 Vera’s most influential encounter, though, happened in the break following her talk. An intrigued Rudolph Minkowski, who had fully retired in 1965, struck up an animated conversation of considerable length, which he concluded by asking her when she would publish her remarkable results. “I ­don’t know. ­There are many more regions we could observe,” was the response. Minkowski, “a large, friendly, and bearlike person” sternly commanded her: “you should publish it now!” 46 She

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Fig. 8.5 The graph illustrating the rotation curve of M31 mea­sured by Rubin and Ford, as published in The Astrophysical Journal in 1970 (volume 159, page 390).

took that excellent advice to heart and, early in July 1969, submitted “Rotation of the Andromeda Nebula from a Spectroscopic Observation of Emission Regions” to The Astrophysical Journal. The revised version, following peer review, was accepted six weeks l­ater.47 Starting at the galactic nucleus, the rotation curve rises steeply to a maximum of 225 km / s over 400 parsecs (1,300 light years). Vera pointed out that this “indicates a rapid rotation for the nucleus.” The velocity then plunges to a deep minimum near 2 kpc (6,300 light years). The explanation for this initial rise and fall lies with the distribution of stars in the nucleus. As Newton found, the stars are driven around at speeds governed by the gravitational attraction of the total mass inside their orbits. Initially, that mass rises with distance from the center ­because more and more stars become encompassed. But then, beyond 400 parsecs, ­there is a region where “the density is very low and the rotational velocities are very small”—­about 55 km / s, in fact. We are now well outside the dense pack of stars forming the central bulge of the galaxy. Using the section of the curve just from the center to this far out, Rubin calculated that the central bulge contributes six billion solar masses.

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Beyond its 2 kpc minimum, the rotation curve climbs steadily t­ oward a new peak at 9 kpc, where velocities hit a maximum of 270 km / s. ­A fter that, the curve slopes down g­ ently for a while but appears to have flattened out at the 250 km / s level by the time it reaches 24 kpc, the limit of her data set. The form of the rotation curve between 3 and 24 kpc from the center is dictated by the amount of material in the disk beyond the concentrated heart of the galaxy. Vera calculated the mass of the disk to be two hundred billion solar masses, half of it within 9 kpc of the center. Comparing her results with the interpretation the radio astronomers had put on their 21-­centimeter radio emission, she estimated that clouds of hydrogen atoms between the stars account for between 4 and 8 ­percent of the mass of the disk. Despite her private conviction that something odd was making the rotation curve unexpectedly flat at the outer limit of her observations, she remained cautious in what she committed to print, writing: “The mass density near R = 24 kpc is extremely sensitive to the shape of the rotation curve in this region, and hence is of low accuracy.” She had found that some attempts to fit a line mathematically through the outermost data points produced a rising curve. This seemed so unlikely she preferred to put in the condition that the computed curve should remain flat out at 24 kpc, which was how she perceived the trend by eye, stating what was self-­evident—­that the velocities w ­ ere “not decreasing.” She added, “We know that the density is low beyond R = 24 kpc; the impor­tant question is how soon it becomes negligible.” The assumed low density in this region she connected with the dearth of vis­i­ble evidence for material in the galaxy farther out but Vera refused to speculate about why the rotation curve was not falling, stating simply that “extrapolation beyond that distance is clearly a ­matter of taste.” Between the lines, ­there was a clear hint of something unexplained that did not add up. As yet, it had no name. In the final part of their classic paper, Rubin and Ford compared M31 with our Galaxy. Ever careful, Vera realized t­ here was a trap for the unwary: many astronomers had arrived at estimates for the dynamical properties of the Milky Way galaxy by assuming that M31 and the Milky Way w ­ ere similar. Scientifically, this was a reasonable assumption, but it meant that any comparison was flawed b­ ecause the data sets were not in­de­pen­dent. It gave rise to a situation of “seeing what we are looking for.” Vera dealt with that by updating ­earlier rotation curves for our Galaxy with more recent data from radio observations. With that adjustment, the similarity between the

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Rubin-­Ford rotation curve for M31 and Maarten Schmidt’s 1965 curve for our Galaxy was remarkable, with the intriguing exception that M31’s rotation decreased more slowly at large distances from the center. Vera put that down to M31 having a 20 ­percent larger mass than the Milky Way.48 Rubin and Ford had been satisfied with the comparison between their rotation curve and mass estimate for M31 and the results obtained by radio astronomers, although Vera pronounced (somewhat unfairly) that “the radio resolution is still poor by optical standards.” They noted that, beyond 3 kpc from the center of M31, “the rotation curve from the optical observation agrees moderately well with the rotation curve from the 21-cm [radio] observations.” As well as the work by the radio astronomy group at DTM, and Mort Roberts at NRAO, Rubin and Ford included in their comparison the 1966 results from a UK team at the Nuffield Radio Astronomy Laboratories of the University of Manchester. Stephen Gottesman, Rod Davies, and Vincent Reddish had surveyed a substantial part of M31 using the 250-­foot dish at Jodrell Bank near Manchester and had come up with a rotation curve in good agreement with Roberts.49 While Rubin and Ford had been busy with their optical studies of H II regions, Gottesman and Davies had been equally hard at work at Jodrell Bank, extending and refining their survey of the radio emission from neutral hydrogen, this time collecting data from the ­whole galaxy. They submitted papers to Monthly Notices of the Royal Astronomical Society early in 1970, which ­were published the following August.50,51 Rubin and Ford’s paper in The Astrophysical Journal appeared in February 1970. It had been “in press” since August 1969, so the latest results from Jodrell Bank came too late for them. Gottesman and Davies, however, knew all about Rubin and Ford’s paper. Most likely they had received a preprint. In their first paragraph they made their repost to the criticism Rubin and Ford had leveled at the resolution achievable with radio observations: “Mea­sure­ments of neutral hydrogen emission in M31 provide data on its velocity distribution with a high resolution in velocity. Since the positional resolution is relatively poor compared with the optical techniques which however have intrinsically poorer velocity resolution, the pre­sent data is complementary to the optical mea­sure­ments of H II regions which are being undertaken at vari­ous observatories at the pre­sent.” It was fair comment. Optical positions ­were more precise, but the radio astronomers had the edge when it came to mea­sur­ing the corresponding velocity. The two methods of obtaining rotation curves, with their dif­fer­ent

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strengths and weaknesses, ­were complementary. Importantly, the similarity between the results demonstrated that the neutral hydrogen and the glowing clouds of ionized hydrogen shared the same kind of rotation, and that the two kinds of rotation curves could be combined or interchanged with confidence. Vera never revisited M31’s rotation curve, but numerous other astronomers acquired velocity data for M31, mostly using the radio technique to observe the neutral hydrogen. Between 1970 and 1975, Mort Roberts secured higher resolution observations at NRAO as part of an extensive proj­ect to mea­sure hydrogen in several large spirals and, at the Mullard Radio Astronomy Observatory of the University of Cambridge, John Baldwin and his doctoral student Darrel Emerson ­were at work making high-­resolution maps of M31 with the Cambridge Half-­Mile Telescope. In November 1969, Vera opened a charming letter from Baldwin, who wrote warmly to express hope “that the Faulhorn wounds have healed quickly.” He was referring to a mishap back in spring when both w ­ ere hiking in Switzerland and Vera fell, breaking her wrist. His letter pleaded for a preprint of her forthcoming paper with Ford, and gave a reason: “Another disadvantage of living h ­ ere [Cambridge] is that we have to wait a long time to receive journals from the States.” His ambition was to complete a map of M31’s hydrogen within three months, in time for the forthcoming IAU General Assembly in Brighton, Sussex. Her assistance would be “highly relevant to what range of velocities we must plan to observe” to achieve that goal.52 Vera responded by calling Baldwin’s M31 plans “spectacular!” and sending what he needed. A ­ fter asking him to attempt observations near the nucleus, she signed off: “I envy you with only three months observations—we have been at this since 1966.”53 Emerson produced a series of papers on his study of M31. In one of them, he compared his radio results, which extended out to about 30 kpc, with the rotation velocities Rubin and Ford mea­sured, and also the outcome of a more comprehensive optical survey published in 1975 by Jean-­Michel Deharveng and A. Pellet of the Observatory of Marseille, France, who had used the 200-­inch Palomar telescope.54 He found “no significant systematic differences” in e­ ither case.55 Roberts and Whitehurst at NRAO also extended the velocity curve out to 30 kpc, finding that it continued flat.56 As they could see nothing beyond 26 kpc visually, they speculated on how many dwarf stars, too faint to be

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Fig. 8.6 A wide-­fi eld image of M31 on which is superimposed the rotation curve mea­s ured by Rubin and Ford, together with additional points, farther from the center of the galaxy, mea­s ured by radio astronomers Morton Roberts and Robert Whitehurst. A very large print of this hung for many years in Vera’s office at DTM. (DTM, Car­n e­g ie Institution of Washington)

vis­i­ble, would be needed to account for such a significant mass. A ­simple calculation produced the answer that a population of rather common dwarf stars, about as far apart as stars in the solar neighborhood, would suffice if they ­were distributed uniformly throughout the extended disk. The mass distribution that the radio astronomers had computed boosted Vera’s confidence that significant mass was required at large radius to keep the velocity from decreasing. She added the NRAO radio data to a large image of M31 she displayed in her office, with her rotation curve superimposed. Vera’s striking montage of the Andromeda Galaxy, its optical rotation curve, and the extended radio data is a vivid image. It would eventually become iconic in popu­lar accounts of the long story of the search for dark m ­ atter in the universe. As more radio data accumulated, it became clear that ­there was a discrepancy in the outer reaches of M31 between the composite rotation curve from neutral hydrogen observations and the Rubin-­Ford rotation curve. So, in 1987, Stephen Kent of Harvard de­cided to try to s­ettle the m ­ atter by making a fresh attack on optical observations. He had access to a very large telescope—­the Multiple Mirror Telescope with light-­gathering power equivalent to a single mirror with a dia­meter of 4.5 meters—­and a spectrograph with an electronic detector. Unsurprisingly, his data points w ­ ere not scattered around the average as much as t­ hose of the e­ arlier observers. Happily

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he concluded that, along the major axis of the galaxy, the optical and radio observations “agree with each other in detail.”57 Although establishing an optical rotation curve for M31 had been Vera’s primary objective, she also had a secondary question in mind. She was aware of the kinds of astrophysical information she could glean from image-­tube spectra and was excited by the possibilities of what the results might reveal. So she investigated the extent to which the emission line spectra varied between regions at increasing distance from the nucleus. At this time, barely anything was known about the abundance and distribution of dif­fer­ent chemical ele­ments through a galaxy, or about the physical conditions in interstellar clouds, such as temperature and density. ­There was ­little, apart from her knowledge of atomic physics, for her to draw on. In the fall observing seasons of 1968, 1969, and 1970, Rubin and Ford obtained twenty-­three high-­dispersion, long-­exposure spectra across the nuclear bulge, at sixteen dif­fer­ent ­a ngles. The geometrical coverage of their long-­slit spectra opened a win­dow on the dynamics of the bulge. Vera mea­ sured emission lines of hydrogen, helium, oxygen, nitrogen, and silicon. She concluded that the gas in the nuclear bulge forms a very thin central disk extending out to 400 parsecs. Her maximum estimate of its mass was 100,000 solar masses, or up to 0.01 percent of the mass of the nuclear bulge.58 The most remarkable outcome of her investigation was the discovery that gas in the nuclear disk not only followed a complicated pattern of circular motions, but was also expanding, and even showing signs that some might be falling inward. When Vera managed to disentangle t­ hese three components, she found the ionized gas had a velocity of 60 km / s away from the center. Her husband, Bob, made an unpublished calculation showing that, at ­those speeds, the gas would have lost all its kinetic energy in a few hundred parsecs, and hence the mass lost from the region out to 400 parsecs was no greater than 0.01 solar masses per year. Although this was considerably less than Münch had surmised in his 1960 paper, it was also rather more than his revised estimate two years l­ater, and Vera had produced far superior data, of course.59 She toyed with the idea that the expanding gas might be evidence of an explosive event at the center of the Andromeda Galaxy a few million years ago. Photo­graphs of galaxies such as M82 and NGC 1275, and smaller objects such as the Crab Nebula, displayed vivid evidence of explosive phenomena. From her analy­sis of M31, however, she concluded that any pyrotechnics must have been ­little more than a damp squib.

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In a “compare-­and-­contrast” exercise, Rubin and Ford noted the similarities between the nucleus of our Galaxy and that of M31. Both have a flattened, rapidly rotating, nuclear disk, and while material is leaving the nuclear region, a small amount of ­matter seems to be ­doing the opposite and falling inward. One notable difference between them was the absence of a high-­energy object in the nucleus of M31. By contrast, our Galaxy has a compact and very power­ful radio source—­Sagittarius A—at its center. Vera was struck by the similarity of the inner disks of gas in the two spirals. Ten years ­earlier, in the Netherlands, Jan Oort’s radio astronomy group had observed hydrogen in the central region of our Galaxy for an incredible 2,400 hours. The Dutch team had been astonished by how thin the nuclear disk was: just one-­hundredth of the disk’s dia­meter.60 Vera cited their paper to support her claim that M31 “exhibits all the regularity in structure generally associated with a non-­explosive galaxy,” ­because a thin disk could never form in a nucleus where t­here had been violent events. She felt she could, with some confidence, put forward the hypothesis that the gas disk in M31’s nucleus was built of remnants cast off by evolving ­giant stars. Additional evidence from Vera’s spectra supported that claim. She discovered that the ele­ment nitrogen was twice as abundant in the nuclear disk of M31 as it was in the Sun. This result must have pleased Vera, ­because Manuel Peimbert had observed the nuclei of galaxies M51 and M81 at Lick Observatory and shown that both had excess nitrogen compared with the Sun. He deduced that “the interstellar material in the nuclei of both galaxies does not have solar chemical composition.” 61 Vera surmised that “This overabundance of nitrogen relative to hydrogen could arise ­because the gas has been pro­cessed through a generation of stars, making it unlikely that we are observing primordial gas left over from the formation of M31.” For Vera, t­hese forays into the inner nucleus and extensive disk of the Andromeda Galaxy ­were a lot of fun, to use the word she most often chose to describe what she did. It had been an exciting and adventurous proj­ect, in keeping with her philosophy of ­doing science through very careful observation, all the while enjoying it. She had verified in a convincing way that the rotation curve of M31 flatlines out to at least 24 kpc, a trend that Mort Roberts’s team of radio astronomers at NRAO would soon extend to 30 kpc. She had firmly established the observational basis for the existence of a g­ reat deal of mass in the disk of the Andromeda Galaxy, adding further credibility to what the radio astronomers had found. Her value for the mass-­to-­

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luminosity ratio of the outer disk, fifteen to twenty times higher than for the stellar population in our own vicinity, appeared to require huge numbers of dim and dead stars to be lurking ­there. But was this something rare or peculiar, or did other galaxies display similar flat rotation curves? By the end of the 1970s, astronomers would have the answer. And the Rubin-­Ford team would have made a significant contribution to the mounting observational evidence.

CHAPTER 9

BRIGHT LIGHT ON DARK M ­ ATTER

V

era Rubin and Kent Ford ­were well pleased with their rotation curve for Andromeda, the most extensively studied galaxy other than our own.1 Still, M31 was but a single galaxy, and Vera was excited by the idea of extending the scope of her research to more spiral galaxies. Her consistent line of thinking was that the evolution of galaxies and the differences among spiral galaxies—in their size, their physical appearance, and the distribution of mass within them—­would be understood only through careful and systematic study of the internal dynamics of as many of them as pos­si­ble. Constructing their rotation curves would be an impor­tant ele­ment of such an investigation. By 1975, Kent Ford had installed an image tube on a spectrograph at the 4-­meter Mayall Telescope at Kitt Peak National Observatory and, when the Mayall telescope’s twin was completed at the Cerro Tololo Inter-­A merican Observatory in Chile in 1976, an image tube went on a spectrograph t­here, too.2 With t­hese new observing tools at her disposal, and access to both northern and southern skies, Vera was determined to investigate w ­ hether the mass distribution and internal dynamics of spiral galaxies ­were related to their physical appearance. She planned her observations according to a scheme devised in 1926 by Edwin Hubble for classifying galaxies by shape, which he thought represented successive steps of galaxy evolution. He divided spiral galaxies into a sequence of three classes—­Sa (tightly wound spirals), Sb (more loosely bound ones), and Sc (open spirals)—­but, some fifty years l­ater, it was obvious that galaxy evolution was far more complex than Hubble had ­imagined. From 1976 through to 1986, the high-­output Rubin-­Ford partnership worked intensively on securing spectra of high-­luminosity spiral galaxies spanning across much of their disks. Their collaboration resulted in thirty-­ five papers for The Astrophysical Journal and a further eleven in The Astronomical Journal. ­Every one of them added to Vera’s growing reputation as a

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Fig. 9.1 Vera Rubin in the control room of the 98- ­inch (2.5- ­m) du Pont telescope at the Car­n e­gie Institution’s Las Campanas Observatory in Chile. The photo­g raph was taken in 1978, the year a ­ fter the telescope began operations. (DTM, Car­n e­gie Institution of Washington)

highly competent observational astronomer. Kent Ford was her principal colleague throughout, but other coworkers joined the campaign at vari­ous times, including Norbert Thonnard, Charles J. Peterson, David Burstein, Morton Roberts, and Bradley C. Whitmore. Vera’s unswerving determination to get high-­quality data on galaxies in order “to relate their dynamical properties to other galaxy par­a meters” drove a demanding observing schedule. To begin with, they deliberately excluded galaxies in groups or clusters to ensure that their targets w ­ ere not being compromised by the gravitational attraction of neighboring galaxies.3 During her year at La Jolla in 1963–1964, Vera had assisted the Burbidges with their program of plotting galaxy rotation curves. The Burbidges,

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however, had been able to probe only the bright central regions of galaxies. Now, ten years ­later, Vera was well placed to mea­sure accurate rotation velocities with the Car­ne­gie image-­tube spectrograph across much of the vis­i­ble extent of galaxies. By the time she started her observing program in 1976, the radio astronomers who ­were making observations of the 21-­centimeter emissions from neutral hydrogen ­were adding to the number of spiral galaxies known to have flat rotation curves. The first such galaxy had been M33 in Triangulum. Louise Volders of Leiden discovered that its rotation curve was so flat she could draw it with a ruler. She published her finding in 1959, without remarking on the pos­si­ble significance.4 Vera ­later commented that “the lack of impact on the astronomical community is curious; perhaps the instrumental capability was doubted.”5 ­There could be no such doubt a­ fter late 1971, when Seth Shostak, a gradu­ate student at the Owens Valley Radio Observatory, submitted his PhD thesis. He included a rotation curve for NGC 2403 and asserted that “The overwhelming characteristic of the velocity field is the practically constant velocity field seen over much of the object.” 6 This was the first unambiguous determination by a radio astronomer of a flat rotation curve in a spiral galaxy.7 Shostak and his supervisor, David Rogstad, soon published results on the properties of five spirals, finding many surprising similarities between them, both in the way hydrogen was distributed and in the flat rotation curves that lacked any hint of dipping down at the outskirts. Furthermore, for ­these five galaxies, the mass-­to-­light ratios grew steadily with distance from the center, reaching about twenty at the outer limit of detection.8 The Owens Valley authors concluded that their observations “confirm the requirement for low-­luminosity material in the outer regions of ­these galaxies.” For three of their five galaxies, the mass-­to-­light ratio amounted to three times the established average value for spirals.9 Meanwhile, the NRAO group led by Morton Roberts had extended its analy­sis to the spirals M81 and M101, discovering that they, too, had flat rotation curves. The interpretation of the data was unambiguous: The three galaxian rotation curves decline slowly, if at all, at large radii implying a significant mass density at large distances. We must conclude that spiral galaxies must be larger than indicated by the usual photometric mea­ sure­ments. . . . ​The pre­sent data require that the mass to luminosity ratio vary with radius, increasing in distance from the center.10

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By the mid-1970s, astronomers w ­ ere openly confronting the apparently excessive masses of galaxies and what the invisible material might be. In September 1974, Roberts reviewed the importance of radio observations for extending galactic rotation curves, persuasively arguing that the implied mass excess might be due to red dwarf stars—­the coolest, smallest, and most common type of star in the Milky Way.11 By now the theorists hotly debated the observed mass discrepancies in galaxies: What was this dark ­matter? Did it r­ eally exist, or was it an abstract invention of excessively ingenious minds? How much ­matter is ­there r­ eally in the darkness of the universe? When she initiated her program on spiral galaxies, Vera was aware that radio astronomers w ­ ere accumulating evidence for flat rotation curves. Her scientific agenda, however, was not primarily driven by a wish to acquire rotation curves and compete with radio astronomers. She saw her own mission, as an astronomer who made high-­quality optical observations, as dif­ fer­ent. The information she could glean about galaxy dynamics from her optical spectra was complementary to the information about galaxies the radio astronomers ­were gathering. Rotation curves ­were for Vera in some sense incidental to investigating the vari­ous properties of galaxies, at least when she first started. Vera did not ­really concern herself about the wider implications of flat rotation curves. She saw that as the job of o­ thers. But the time would come when she would acknowledge the part her results ­were playing in the dark ­matter debate and accept that she was inevitably involved in it. “I think I was sort of a coward,” she confessed in 2007. “I was always interested in getting more data, rather than making sweeping conclusions,” but “the more we did, I think the more convincing it got.”12 In April 2001, when Vera made a pre­sen­ta­tion at a Space Telescope Science Institute symposium on the dark universe, she went over the history that foreshadowed her own discoveries. She began her frame-­setting essay with ideas that had circulated in the eigh­teenth and nineteenth centuries proposing the existence of dark stars in the heavens.13 The intuition of the Reverend John Michell profoundly impressed her b­ ecause, back in 1784, “200 hundred years before we knew of black holes,” he had ­imagined a star “500 times the solar radius, but of equal density”: it would be invisible b­ ecause all of its light would return to the dark star “by its own proper gravity.”14 Vera also mentioned that, in the early twentieth ­century, Jacobus Kapeyn estimated “the amount of dark m ­ atter” in a par­tic­u­lar model of the universe.15

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And she noted that James Jeans had estimated in 1922 that t­ here are “about three dark stars in the universe for e­ very bright star.”16 The history of con­temporary efforts to understand dark ­matter began with Fritz Zwicky (1898–1974), who graduated in mathe­matics and physics from ETH Zürich. In 1925 he emigrated to Pasadena, California, ­a fter being awarded an international fellowship by the Rocke­fel­ler Foundation. Caltech appointed him professor of astronomy from 1942 and he was a staff astronomer at the Car­ne­gie Observatories for most of his c­ areer. ­There he made six cata­logs of thousands of galaxies and galaxy clusters. Unfortunately, his abrasive, out­spoken, and disrespectful rhetorical style tarnished his stature as a brilliant and original astrophysicist, but his reputation t­ oday has soared as a result of the evidence he discovered suggesting the presence of dark ­matter in the universe. In 1931, two of Zwicky’s colleagues at Mount Wilson, Edwin Hubble and Milton Humason, published an improved version of the s­ imple relationship between distance and velocity for far-­off galaxies, now known as the Hubble-­ Lemaître law. Their paper included details of velocities for seven of the brightest objects within the g­ reat Coma cluster of galaxies.17 This data enabled Zwicky to analyze the overall dynamics of the eight hundred or so galaxies making up the Coma cluster. The seven member galaxies he looked at had “differences in velocity of at least 1,500 to 2,000 km per second,” and yet they had not been flung out of the cluster, as would have been expected. Zwicky calculated how massive the Coma cluster must be to keep hold of its members. He reached an astonishing conclusion: In order to obtain the observed value of an average Doppler effect of 1000 km / s or more, the average density [of m ­ atter] in the Coma system would have to be at least 400 times greater than that derived on the grounds of observations of luminous ­matter. If this would be confirmed, we would get the surprising result that dark ­matter [dunkle Materie] is pre­sent in much greater amount than luminous ­matter. . . . ­These considerations show that the ­great dispersion in the Coma system (and other dense nebular clusters) harbors a prob­ lem that is not yet 18,19 understood.

A similar result for the Virgo cluster was soon forthcoming from Mount Wilson, where Sinclair Smith had drawn on the velocities of twenty-­seven bright galaxies from Humason’s lists and five from Slipher’s. He made additional observations of a further nine faint galaxies to make his sample six

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times larger than Zwicky’s. Smith deduced that “the [Virgo] cluster is neither condensing nor breaking up, but is a fairly stable assemblage, more or less held together by its gravitational field.” On that basis, Smith estimated a mass of two hundred billion solar masses for the Virgo cluster, vastly exceeding Hubble’s ­earlier value of one billion solar masses, based on the surface brightness of the cluster galaxies.20 Meanwhile, Zwicky critically evaluated the methods then available for estimating the masses of galaxy clusters, concluding that assessments based on luminosities or internal motions w ­ ere unreliable on account of meager data, which had led to much guesswork. To improve his analy­sis of the dynamics of the Coma cluster, he refined the s­imple mathematical approach he had employed in 1933, but he realized that, most of all, he needed a much better photographic survey. With this in mind, Zwicky successfully advocated for the construction on Palomar Mountain of an 18-­inch Schmidt camera, a telescope designed especially for photographing large areas of sky. When it came on line in September 1936, the Coma cluster was the first target. Zwicky spent three nights a week taking thirty-­minute exposures.21 By day, he carefully studied and mea­sured the films, locating a further two hundred very faint galaxies: he estimated that t­ here w ­ ere at least fifteen hundred of them. For the cluster as a ­whole, he calculated a mass-­to-­light ratio of 500:1, a ­factor of about fifty greater than the radio astronomers ­were obtaining for individual galaxies.22 This result unnerved Zwicky. He proceeded cautiously when he submitted the paper in June 1937, being properly concerned that even now his data might not be good enough, and fretting that stars lying between the galaxies might be distorting the result. Jan Oort became the next famous astronomer to make a passing mention of a galaxy with a puzzling mass excess. In 1940, he investigated the luminosity and dynamics of the supergiant lenticular galaxy NGC 3115, which is not a member of a large cluster. Milton Humason gave Oort access to some “unpublished details of his mea­sures of the rotation of NGC 3115.” From t­ hose figures Oort found that, in the outer parts, the mass-­to-­light ratio was very high: 200:1. Initially he considered w ­ hether absorption of light by dust was boosting the ratio, but soon concluded that this was unlikely, and offered the hypothesis that 99.5 percent of the population of stars must consist of extremely faint dwarfs. Astronomers scarcely noticed the intriguing insights of Smith and of Zwicky. Zwicky’s 1933 paper had zero impact, and the more comprehensive

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version published in 1937 fared ­little better. In its first twenty years ­there w ­ ere eigh­teen citations of it, half of them by Zwicky himself. In 1954, Martin Schwarzschild politely discarded the “­earlier investigation by Sinclair Smith and Zwicky” ­because of the “bewilderingly high value [of 800] for the mass to luminosity ratio in the Coma cluster.” For other clusters with large mass excesses, he speculated that “exhausted faint stars” could perhaps be a solution, citing Oort’s suggestion for NGC 3115.23 Three years l­ater, in 1957, Geoffrey Burbidge took a dif­fer­ent stance, adopting Zwicky’s conclusion that “much material exists in regions lying between the galaxies.”24 Thirteen years ­after that, in 1970, the Australian astrophysicist Kenneth Freeman became one of the first ­people in the modern era to point out that “spiral galaxies contain a large fraction of dark ­matter.”25 At the end of a theoretical paper on the formation of the disks of spiral galaxies, he added an appendix in which he compared the observed and predicted rotation curves for NGC 300 and M33. From that analy­sis, he concluded that, if the 21-­centimeter radio data ­were correct, ­there must be in ­these galaxies additional m ­ atter, which is undetected, e­ ither optically or at 21 centimeters. Its mass must be at least as large as the mass of the detected galaxy, and its distribution must be quite dif­fer­ent from [that] which holds for the optical galaxy.”26 This was only four months a­ fter Rubin and Ford had published the optical rotation curve of M31. Vera had no taste for vivid speculation on the cause of its flattening. It seems that Freeman likewise was avoiding potential ridicule by modestly floating his idea as an afterword in the appendix. To complete this survey of the “dark ­matter debate” as it stood in the 1970s, when Vera launched her revolutionary observing program for spiral galaxies, we should note some other pointers to the pos­si­ble existence of dark ­matter then in circulation. By this time, the scope of cosmological research had been utterly transformed b­ ecause it was deeply driven by a revolution in our knowledge of the universe: the observational evidence for an explosive origin—­t he “big bang.”27 ­There ­were multiple competing models attempting to describe the expanding universe. The overwhelming objective of research was to determine ­whether the universe was open and would only continue to expand, or closed, in which case the expansion would eventually be reversed. Theorists addressed a ­simple question: Is the universe massive enough for the galaxies to cling together, or are they destined to fly apart

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forever? The crucial number that tipped the balance between ­these two main possibilities was the density of material that would “close the universe.” How much mass is needed to weigh down the expansion and reverse it? And, if the universe has that critical mass, why c­ an’t we see it? The cosmologists livened up their discussions by using the term “missing mass,” first employed in 1967, for the extra ­matter over and above what we can obviously see that would be needed to guarantee the closure of the universe.28 At that stage it seemed to the theorists that as much as three-­quarters of the mass of the universe could be invisible. Even that, however, would be shown to be an underestimate. In 1973, Jeremiah Ostriker and James Peebles of Prince­ton University robustly advanced the case for invisible m ­ atter with their calculations relating to how galaxies hold themselves together in the long term. They found, as other researchers suspected, that a rotating disk of stars or gas would become wildly unstable, leading to the formation of a ­giant bar structure. That had evidently not happened in the case of our Galaxy, or to any average barred spiral, where the central mass is relatively modest and accounts for only one-­tenth of the total starlight. So, although rotation curves w ­ ere indicating ­there must be a g­ reat deal of unseen gravitating m ­ atter far from the centers of normal galaxies, that m ­ atter could not be lurking in the almost two-­dimensional flat disk where the vis­i­ble ­matter resides. Ostriker and Peebles duly looked to the third dimension. They argued for the probable existence of a dark and massive sphere—­a halo of ­matter—to stabilize the system. It would have a very large mass-­to-­light ratio. Effectively, theirs was a massive “engineering solution” to suppress the intrinsic instability of a rotating disk. Their line of reasoning was based on a theoretical argument that something (dark m ­ atter) must exist to explain the nonexistence of another t­ hing (an unstable disk). This method of inference was quite properly regarded as unpersuasive by the sensible astronomical establishment with its “show us the evidence” mindset.29 Within a year, that evidence came to light, as Vera found when she eagerly opened the October 1974 issue of The Astrophysical Journal. Her eyes alighted on a brief paper about galaxy masses and the mass of the universe by Ostriker, Peebles, and Amos Yahil of Tel-­Aviv University. She found its message “stunning.” H ­ ere’s how the paper that so amazed her began its opening paragraph:

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­ ere are reasons, increasing in number and quality, to believe that the masses of Th ordinary galaxies may have been underestimated by a ­factor of 10 or more. Since the mean density of the universe is computed by multiplying the observed number density of galaxies by the typical mass per galaxy, the mean mass density of the universe would have been underestimated by the same ­factor.30

The three authors noted that the observed flat rotation curves for spiral galaxies implied that the mass enclosed by any par­tic­u­lar radius rises with distance from the center. When they plotted all of the mea­sure­ments of our Milky Way galaxy to greater and greater distances, they found that the mass enclosed within a sphere progressed according to a s­ imple rule: it was directly proportional to the radius of the sphere, out to a distance of about 300 kpc, where it reached a trillion (1012) solar masses. Therefore, most of the mass of our Galaxy is more than 100 kpc from its center. Ostriker, Peebles, and Yahil estimated similar mass distributions from rotation curves determined by radio astronomers. For ­these spirals, the mass increased almost linearly with radius, out to nearly 1 Mpc. It seemed an extremely strange result ­because the distribution of the mass was totally at odds with the distribution of luminous stars. This peculiarity strengthened the case that unseen massive galactic halos w ­ ere contributing at least ten times as much mass as the luminous stars in the flat disk and the nucleus. With this exercise in cosmology, the Prince­ton theorists presented a convincing case that our universe contains huge amounts of dark ­matter, although it fell a f­ actor of five short of the magic number needed to lock down the expanding universe.31 When Ostriker looked back on t­ hese results forty years l­ater, he wrote: “It was a g­ reat deal for the astronomical world to swallow. It took time and yet more evidence to convince most of the astronomers.”32 About the same time, a team of cosmologists had produced a compelling argument for what they called massive galactic “coronas.” Jaan Einasto, Ants Kaasik, and Enn Saar of Tartu Observatory, Estonia, reviewed data published by ­others on 105 pairs of galaxies with known radial velocities and good distance estimates. E ­ very pair displayed signs that they w ­ ere interacting with each other. By looking at their dynamics and how mass was distributed, the trio concluded that the “mass of galactic coronas exceeds the mass of the populations of known stars by one order of magnitude,” and they hypothesized the existence of “hidden ­matter.”33

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Fig. 9.2 Kent Ford (left), Norbert Thonnard, and Vera Rubin in Vera’s office in 1984. (DTM, Car­n e­gie Institution of Washington)

It was at this point in the rapid development of cosmology that Vera was planning her long-­term study of spiral galaxies to satisfy her own interests in galaxies, but it so happened that her work would also help respond to the clamor from theorists for more data on spiral galaxies. Vera designed an imaginative observing program for the Car­ne­gie image-­tube spectrograph on the 4-­meter telescopes at Kitt Peak National Observatory and the Cerro Tololo Inter-­A merican Observatory, in which she would systematically produce rotation curves of spiral galaxies that spanned farther across each galaxy, and in greater quantity, than any optical astronomer before her had achieved. Practical considerations directed her attention to spirals oriented close to edge-on, as is the case for M31. The rotational motion of the orbiting gas and stars in such a galaxy is almost along our line of sight, so a significant difference in velocity can be detected between opposing ends of the major axis. By choosing to observe t­ hese highly inclined galaxies, Rubin and her colleagues could maximize the accuracy of the mea­sured rotational velocities and the masses they deduced. Vera took pride in exercising “extreme care” when selecting her target galaxies, ensuring that they w ­ ere not too similar and that they encompassed a wide range of radii, masses, and luminosities. Between 1973 and 1982, she completed one hundred nights of observing at Kitt Peak and Cerro Tololo, making more than twenty trips, the majority of them with the hands-on support of Kent Ford.34 Vera’s subsequent, meticulous analy­sis of the galactic spectra resulted in two dozen papers in The Astrophysical Journal, summarizing the rotational properties and mass

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distributions of more than sixty spiral galaxies. Six of ­those papers, published in 1978, 1980, 1982 (two), and 1985 (two), are considered below. In 1977 and 1978, Rubin and Ford spent twenty-­eight nights on 4-­meter telescopes obtaining spectra of twelve high-­luminosity spiral galaxies (type Sc). The uncertainty in each mea­sured velocity was generally less than 8 km / s, giving them a data set of high quality and credibility. The twelve rotation curves w ­ ere all approximately flat out to distances of 50 kpc. Vera analyzed the masses and mass-­to-­light ratios in two dif­fer­ent ways. In one of them, she ­adopted the standard picture of a galaxy as disk-­shaped. Her alternative approach followed the lead from Prince­ton and Tartu Observatory and assumed that material was distributed throughout a sphere. Both the disk and sphere models of the mass distribution reproduced the observed rotation curves. The ­spherical models tipped the scales at 1012 solar masses! Vera wrapped up her 1978 paper coauthored with Ford and Thonnard on a cautious note: “The observations presented ­here are thus a necessary but not sufficient condition for massive halos.”35 This was a lost opportunity for her to provide intellectual leadership; she did not explain why the data should be considered insufficient. ­Today we can overlook her self-­confessed timidity and accept this as her first marshalling of evidence from optical observations for the presence of copious dark ­matter in galactic halos, just as theorists had been advocating for five years. At the same time, she emphasized that she was not inferring any connection between her observations and the presence of intergalactic dark ­matter being predicted by cosmologists as a means of “closing the universe.” Also in 1978, rapid pro­gress in the study of galactic rotation curves was being reported on the other side of the Atlantic. On March 17 at 4:00 pm, Albert Bosma, a young radio astronomer at Groningen in the Netherlands, began his public defense of a PhD thesis which was “about to take the world by storm ” and “was the real clincher,” according to Kenneth Freeman of Mount Stromlo Observatory, who had recently spent a sabbatical year at Groningen.36 Bosma had used a new array of radio telescopes at Westerbork in the Netherlands to survey the hydrogen in twenty-­five spiral galaxies. He mapped velocities well beyond the periphery of the vis­i­ble stellar disk with the highest resolution so far achieved by radio astronomers. The most striking feature of the Westerbork rotation curves was that they remained flat (or almost flat) u ­ ntil the last mea­sured point.37 Bosma’s thesis and his two pa-

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pers of 1981 would provide irrefutable evidence of the presence of large amounts of unseen m ­ atter in galaxies.38,39,40 Speaking on the large-­scale characteristics of the Galaxy at IAU Symposium 84, which took place in College Park, Mary­land, in June 1979, Rubin drew attention to Bosma’s study in glowing terms: “An outstanding recent study of rotation curves from 21-cm line observations is due to Bosma (1978).” 41 Vera’s praise was just three months a­ fter Bosma had defended the thesis, barely days ­after the first copies of it would have arrived in the United States by surface mail from Eu­rope, and two-­and-­a-­half years before the full results ­were published (December 1, 1981) in a peer-­reviewed journal. In ­October 1979, when Rubin submitted her 1980 paper to The Astrophysical Journal, she gave his thesis only a brief citation. This suggests that, perhaps ­under pressure to get her 1980 paper in press, she simply had not had sufficient time to assimilate the importance of the bulky typescript. It is also the case that Vera’s papers devoted to presenting observational results ­were usually tightly focused on ­doing just that, although elsewhere she was generous in promoting the work of younger colleagues. By 1980, further observations by Rubin and her DTM colleagues had grown their sample to twenty-­one “galaxies that ­were chosen with extreme care,” according to Vera’s strict criteria mentioned above, plus exhibiting wide-­open spiral arms and a small nucleus: galaxies classified by Hubble as type Sc. Furthermore, Vera’s skillfully selected set spanned a huge range of masses, luminosities, and radii, the largest galaxy extending to thirty times the size of the smallest. She and Kent Ford w ­ ere the first to observe the outer regions and dynamics of most of ­these galaxies and to publish a systematic study of their rotation curves.42 All of them had orbital speeds that r­ ose rapidly from the nucleus out to about 5 kiloparsecs, with a slower rise thereafter. Not one had a curve that was falling at the farthest mea­sured point. What Vera found surprising was that all of ­these extended rotation curves had the same shape: she could stack them one on top of another, with no scaling according to the size of the galaxy, “to form a common rotation curve.” At large distances from the center, the implied mass just kept on ­going up and up, even at the limit where no ­matter could be seen. On this, Vera’s comment in the 1980 Astrophysical Journal paper was unambiguous: “The conclusion is inescapable that non-­luminous ­matter exists beyond the optical galaxy.” The universal dark m ­ atter sought by

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cosmologists seemed to be preferentially concentrated around galaxies, which would have profound consequences for theorists working on the origin and formation of galaxies in the early universe. It is Vera’s most influential paper, with more than nine hundred citations. Almost a quarter of ­these citations have been since her passing, and the annual citations by physicists and cosmologists continue to soar: it has supplied ample food for thought for a generation of theorists.43 Vera, who always delighted in extracting all she could from her data, asked another question: How many times have t­hese galaxies rotated? The similarities of their rotation curves told her that the smallest spirals had whirled around about fifty times, whereas the outer parts of majestic ­giants had serenely completed only a few rotations since their formation. The ­giant galaxy UGC 2885, which holds the rec­ord as the largest known spiral, had “under­ gone fewer than ten rotations in its outer parts since the origin of the universe” but it still maintained its wonderfully symmetrical spiral structure. Furthermore, ­there was a change in velocities across a spiral arm: the outer edge of one arm was g­ oing faster than the inner edge of the next arm. This was compelling evidence that the spiral pattern is a rotating wave that advances more slowly than the streaming motion of the stars. A similar phenomenon occurs on the freeway, when traffic congestion persists for long ­after an obstacle has been removed. In 1981, the DTM trio of Rubin, Ford, and Thonnard teamed up with David Burstein to make a more thorough analy­sis of the mass distribution in the same galaxy sample. They uncovered several correlations between fundamental properties such as mass and luminosity, a research outcome that confirmed Vera had indeed taken “extreme care” in assembling the sample. Her exquisite judgment in selecting targets had paid off yet again: the form of the mass distributions in the sample uniformly scaled with galaxy size. Vera had put together a consistent set of observations from which it was pos­ si­ble to make like-­for-­like comparisons with confidence. She had succeeded in shutting the dome on so-­called “pathological” galaxies—­oddballs that could screw up statistical analy­sis. She handed the theorists results that they immediately took rather seriously. The first paragraph of her paper with Ford, Thonnard, and Burstein informed readers that her latest sampling of “normal spiral galaxies has relevance to the larger prob­lems of non-­luminous ­matter in the universe, and of the mass of the universe.” And in their final paragraph we find this key statement: “Since the majority of the Sc galaxies in

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Fig. 9.3 A Hubble Space Telescope image of the spiral galaxy UGC 2885, nicknamed “Rubin’s galaxy.” Located 232 million light-­years away, in the constellation Perseus, it is thought to be the largest spiral galaxy in the local universe. The very bright object in front of the galaxy’s disk is a foreground star in the Milky Way. (NASA, ESA, and B. Holwerda, University of Louisville)

this sample are not in large clusters, all of ­these conclusions are consistent with the presence of virtually nonluminous massive halos in field Sc galaxies. The distributions of both forms of ­matter (luminous and nonluminous) seem to be tightly coupled over the optical image.” 44 At the point that Vera and her coworkers wrote that, the enthusiasm for the idea of abundant dark ­matter weighing down clusters of galaxies had gathered momentum. Vera’s 1978, 1980, and 1982 papers document how she, too, came to accept the case for dark ­matter’s being clumped around galaxies rather than existing just as an extension of the background ­matter of the universe: even isolated field galaxies possess massive halos. A comprehensive review undertaken in 1979 by Sandra Faber and John Gallagher concluded that halos exist around all types of galaxies, not only spirals.45 Vera’s observing program continued at a steady pace and, by 1982, rotational properties of twenty-­three type Sb galaxies w ­ ere in hand.46 The quest

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Fig. 9.4 A page of twenty-­three flat rotation curves for Sb galaxies, as published by Rubin, Ford, Thonnard, and Burstein in The Astrophysical Journal in 1982 (volume 261, page 449).

reached its conclusion in 1985 when sixteen type Sa galaxies (spirals with large central bulges and tightly wound arms) ­were added to the set, making a total of sixty field spiral galaxies with dynamical properties that had been observed and analyzed consistently. Vera Rubin’s observational protocols ensured data of the highest quality and largely ­free of bias or se­lection effects. The sample

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encompassed a large range of luminosity, a property that is typically indicative of size and mass. The galaxies’ rotation curves conformed to similar shapes, although the Sa galaxies, with their prominent nuclei, had higher maximum velocities than the Sb and Sc galaxies. Significantly, the rotation curves did not reflect marked structural differences across the three galaxy classes. Vera noted that “the rotation curves we have obtained for Sa, Sb, and Sc galaxies bear l­ittle relationship to the rotation curves that would be predicted from the distribution of optical luminosity in ­these galaxies.” That led her to question what fraction of the mass of a spiral galaxy is contributed by material outside the disk. A ­ fter some consideration, she felt that the vis­i­ble material might be responsible for half the ­matter in the disk, in which case the dark ­matter must comprise “at least two components—­one disk-­ like, the other arranged in a more nearly s­ pherical distribution.” That is, she argued for a halo.47 As Vera would often say when questioned about this line of research, it was never conceived as an investigation into dark ­matter: it was always an investigation into galaxies. In an interview recorded in 1995 on her role in the dark ­matter story, she put it this way: “My interest actually was trying to understand why galaxies came in dif­fer­ent forms. Why some w ­ ere spirals and disks and o­ thers w ­ ere spheroidal. I thought that if I could understand how the stars orbited, I would be able to understand why they came in ­these dif­fer­ent patterns.” 48 Her attempts to understand the universe of galaxies w ­ ere grounded in the classical tradition of natu­ral philosophy: gaining knowledge through observation. The busy sessions at telescopes w ­ ere motivated by a quest for the best pos­si­ble data on how galaxies actually work. She was excited by the endless variations of structural appearances, sizes, masses, luminosities, and dynamics of galaxies, and always searching for correlations. Although Vera did not set out to throw light on dark m ­ atter, her observational discoveries about the distribution of dark ­matter in the universe ­were the most striking outcome of her research on galaxies. Her key papers on rotation curves made a significant contribution to the observational evidence a ­viable cosmological theory must explain. Forty years l­ater (as of 2019), they had amassed more than 2,100 citations in peer-­reviewed journals. In 2017, the year ­after Vera’s death, the annual rate passed eighty, and that number kept on climbing, reaching one hundred in 2019. ­These are exceptionally high citation rates for papers by a ground-­based observational astronomer. Indeed, since the beginning of the twenty-­first ­century, they match the citation rates for Hubble’s papers on extragalactic distances.

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Vera never claimed that she “discovered dark m ­ atter,” although ­others have mistakenly said that she did. Nevertheless, ­people ask historians and biographers: Exactly who did discover dark m ­ atter—­or dark energy, or the expansion of the universe? And they expect straight answers. The fact that such questions continue to be posed is a sign that historians are not so sure, ­either b­ ecause ­there is too l­ittle evidence for forensic examination or t­ here ­really is no s­ imple answer. Consider phi­los­op ­ her William Vanderburgh’s view: “Given the length of time it took the astronomical community to come to terms with the evidence for dark m ­ atter, it is reasonable to say that no single scientist was the discoverer of dark ­matter.” 49 It is impor­tant that historians recognize the contributions of ­those whose work has wrongly been neglected but, at the same time, impor­tant that they do not read the history of cosmology backward and, as a result, give undue credit to an individual for a massive breakthrough at a par­tic­u­lar point in time. A discovery may be more of a realization, emerging in dif­fer­ent places at dif­fer­ent times through the efforts of several impor­tant contributors, and then slowly taking root in the communal consciousness. The g­ reat discoveries in cosmology in the last ­century and the pre­sent c­ entury required the fusion of observation, instrument development, theory, intuition—­a nd a touch of serendipity. With regard to the story of dark m ­ atter, Vera came on the scene in the right place and at the right time, with her unique combination of personality and observational skills, to make the valuable contribution for which she w ­ ill be remembered.

CHAPTER 10

THE DYNAMIC UNIVERSE

I

n the interval between completing their major study of the Andromeda Galaxy and embarking on the ten-­year proj­ect to plot the rotation curves of dozens of spiral galaxies, Vera and Kent digressed into something completely dif­fer­ent. In November 1971, they commenced a program in observational cosmology. Vera wanted to know: Is the expansion rate of the universe isotropic—­that is, uniform everywhere—­beyond the immediate neighborhood of the Milky Way? When she launched this substantial proj­ect, the overriding objective of the research in extragalactic astronomy being conducted at the Mount Wilson and Palomar Observatories was the accurate mea­sure­ment of the expansion rate of the universe. No one, however, had designed an observing program specifically to address ­whether the flow of galaxies was strictly in accordance with the relationship Hubble had identified in 1929. Is the Hubble flow isotropic on a g­ rand scale? Vera set out what was motivating her in the Car­ne­gie Yearbook for 1971–1972: In recent years much work has been directed ­toward establishing the rate of expansion of the universe, i.e., the Hubble constant, principally by Sandage and his collaborators. At the same time, analy­sis of the available redshifts has suggested that the Hubble expansion may not be isotropic for nearby galaxies. Implicit in all studies has been the assumption that the Hubble constant is isotropic at redshifts greater than about 4000 km / s. In order to investigate this assumption, we have started a program to determine velocities for a sample of 200 ScI galaxies in the [apparent] magnitude range 14.0–15.0.1

She was the first optical astronomer to tackle this fundamental question from an observational point of view, and a pioneer in searching for the answer. The prelude to her question takes us back to 1927, when Georges Lemaître first established that the universe being in a state of continuous expansion is consistent with the laws of physics.2 He was already familiar with the research of Edwin Hubble, who in 1929 published convincing evidence that

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recession speeds of galaxies are proportional to their distances. That discovery was a huge leap in our understanding of the mechanism of the cosmos.3 In 1931, Lemaître floated his highly imaginative proposal that our universe began with the sudden explosion of an all-­encompassing primeval nucleus (in French, atome primitive) containing the totality of the m ­ atter and energy that exists. The expanding debris of this cosmic firework eventually condensed into clumps, in which galaxies formed, all the while continuing to race apart. Lemaître’s picturesque account of this big bang was regarded initially as ­little more than a fairy story—­until 1946, when the general public learned of it through his popu­lar book.4 George Gamow took it seriously enough to investigate what its physical consequences would be for the origin of the ele­ments.5 For Vera, 1971 ­wasn’t the first occasion on which she had attempted to test ­whether the expansion—­the “Hubble flow”—is the same everywhere or ­whether galaxies deviate from it. As a student at Cornell in 1949–1950, for her master’s thesis, she had queried w ­ hether the universe was rotating as well as expanding. (That work is described in Chapter 3). The thesis had been a simplistic analy­sis of meager data she could glean from publications available at the time, but the exercise had taught Vera how the radial velocities of galaxies could be examined to probe the dynamics of the universe. Although her sample of a hundred or so galaxies was inadequate, it was an innovative start, and she discovered systematic motions in­de­pen­dent of the universal expansion. Back in the 1950s, astronomers knew very l­ ittle about the structure of the universe and the distribution of its galaxies. W ­ ere they strewn at random across the sky, or did their density in space follow hierarchical rules, such as crowding in groups or clusters? Thanks to George Gamow’s interest in this from a theoretical perspective, Vera, as his student, wrote her 1954 PhD thesis on “Fluctuations in the Space Distribution of Galaxies.” 6 Gérard de Vaucouleurs, with whom Vera worked in the 1960s, was one of a small number of observational astronomers who also took a keen interest in this question. He concluded that an enormous assemblage of galaxies, which he termed the Local Supercluster, was majestically rotating about the center of the Virgo cluster. This celestial ballet perturbed the smooth flow of the galaxies due to the expansion of the universe.7 By the mid-1960s, it was generally acknowledged that galaxies are not distributed at random, but also known that in-

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vestigations of their large-­scale motion would require improved techniques for mea­sur­ing their distances. In 1965, Arno Penzias and Robert Wilson detected the cosmic micro­wave background—­that is, the radiation in the universe left over from the big bang. This radiation is uniform enough to act as a fixed reference frame against which the movements of every­thing e­ lse in the universe can be measured— in par­tic­u­lar, the Sun’s speed and direction. As the universe expanded a­ fter the big bang, it also cooled down. ­Today, the fossil radiation corresponds to a temperature only three degrees above absolute zero (3 K). Astronomers realized immediately that the radiation, as viewed from Earth, would appear slightly hotter than average in our direction of travel through it, and slightly cooler in the diametrically opposite direction. Radio astronomers at Prince­ton University ­were quick off the mark in the search for this effect, taking daily scans of the radiation for one year. The temperature variation they w ­ ere looking for, however, amounted to no more than a few thousandths of a degree, and their setup did not reveal significant deviations from uniformity in any direction.8 Signs of it w ­ ere not detected ­until 1969.9 Meanwhile, de Vaucouleurs revisited the issue in 1968, using the pool of published data on radial velocities and magnitudes of galaxies then available to him—­certainly a larger pool than had existed a de­cade ­earlier. By 1971, radio astronomer Paul Henry narrowed down the velocity of the Sun relative to the micro­wave background to a win­dow between 200 and 500 km / s, and the micro­wave results ­were looking broadly consistent with the figures de Vaucouleurs and ­others w ­ ere getting from the movements of 10,11 galaxies. Nevertheless, it was generally believed that the expansion would be the same in all directions at larger distances, the motion of the Sun being attributed to the gravity of the Local Supercluster. In his 1968 paper, de Vaucouleurs concluded that “­there is nothing in the bright galaxy data to contradict the assumption that the large scale cosmological red-­shift is linear and isotropic.” Paul Henry concurred, writing that his findings supported the assertion that “­there is no large motion of the Local Supercluster relative to the more distant frame defined by the 3 K background radiation.” That assertion is what Vera de­cided to check, perhaps encouraged by de Vaucouleurs’s strong statement that “the laws of motion of planets or galaxies are not questions to be de­cided by aesthetic prejudices or reasons of theoretical simplicity, but by a study of the empirical evidence.”12

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The plan was to mea­sure the radial velocities of around two hundred ScI galaxies located beyond the outer limits of the Virgo cluster of galaxies. ­Vera’s ­daughter, Judy, at the time a student at Radcliffe College, undertook the task of selecting the galaxies by examining survey photo­graphs of the sky.13 ScI galaxies are fairly common, easy to identify by their shape, and, roughly speaking, all equally luminous. By early 1973, the proj­ect was yielding interim results so striking that Vera, Kent, and Judy de­cided to release a preliminary report. The seventy-­four galaxies observed up to that point all had radial velocities greater than 4,000 km / s, and the mea­sure­ments ­were largely considered accurate to better than 50 km / s. In one region of the sky ­there ­were twenty-­two galaxies that mostly had recession velocities of about 4,950 km / s, whereas twenty-­eight galaxies across the rest of the sky had velocities nearer 6,400 km / s. The two velocity groups scarcely overlapped. They considered pos­si­ble explanations. Perhaps our Galaxy and its Local Group is hurtling along ­wholesale at 1000 km / s? But that would be in conflict with what the background radiation appeared to be telling astronomers. Maybe it was the consequence of a set of very specific circumstances? For Vera, speculation was very unsatisfactory. Echoing a pronouncement by Shapley thirty years ­earlier, she concluded, “Obviously we are not through with this business.”14 And they ­weren’t. Vera became determined to find the answer to her question: “Is the Hubble expansion isotropic—­uniform in ­every direction—as observed from our Galaxy?” She ratcheted up the observing program to mea­ sure the radial velocities of the program galaxies, mainly done with the 2.1-­meter telescope at Kitt Peak in Arizona and with the 1.5-­meter at Cerro Tololo in Chile. Mort Roberts at NRAO ran a program with the 300-­foot telescope to obtain radial velocities for 125 galaxies from their 21-­centimeter radio emissions. For the analy­sis, Vera selected a subset of ninety-­six galaxies, believing this would help reduce pos­si­ble bias. Their recession velocities spanned the range of 3,500 to 6,500 km / s, corresponding to distances between 50 and 90 kpc. This placed them well beyond the gravitational pull of our Galaxy but not so far that their velocities ­were uncertain. Vera went to g­ reat lengths in her attempts to correct for bias and observational effects, such as absorption in our Galaxy decreasing the apparent magnitudes of the sample objects.15 The major conclusion of the study was that the velocities of recession for this sample of galaxies w ­ ere not as expected if the steady expansion of the

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universe was undisturbed. The variation they observed was consistent with our Galaxy and the Local Group moving relative to the set of ninety-­six sample galaxies. Vera and collaborators concluded that the w ­ hole of our Local Group of galaxies is moving edge-on with a velocity of about 450 km / s in the general direction of the Virgo cluster of galaxies, at odds with the observed departure from isotropy in the micro­wave background radiation, which by 1976 was giving a figure of 300 km / s. They had consulted other colleagues and had done their best to produce a thorough analy­sis, taking into account all the f­actors they could think of that might make their conclusion erroneous. In the acknowl­edgments, the authors write “Special thanks go to Dr. A. R. Sandage and Dr. G. Tammann, whose honest skepticism and piercing questions have forced a much broader analy­sis than we anticipated at the outset.”16 They had clearly racked their brains in search of an explanation for the result, but none was forthcoming. An open season of “honest skepticism and piercing questioning” on what became dubbed “the Rubin-­Ford effect” followed in short order and lasted for several years. Michael Fall and Bernard Jones at the University of Cambridge had already jumped the gun with a paper in Nature a few months before the final results appeared in print, querying the preliminary analy­sis published in 1973. Fall and Jones ­were skeptical of the evidence for large-­ scale anisotropy of the Hubble flow. The Rubin-­Ford effect was a statistical fluke caused by an inhomogeneous distribution of the galaxies in the direction of their sample, they said.17 Martin Clutton-­Brock and Jim Peebles, however, ­were less dismissive. “Some critics have suggested that the Rubin-­ Ford effect may be a mere statistical artefact,” they noted, but they themselves w ­ ere “reluctant to dismiss a carefully made set of observations.” Their inquiry suggested that the Rubin-­Ford sample of galaxies was moving relative to the distant universe at 800 km / s.18 By the early 1980s, cosmologists w ­ ere taking the Rubin-­Ford effect very seriously indeed. Was it real, or cosmic heresy? Their collective thinking had moved robustly in the direction that the cosmic micro­wave background was the absolute frame of reference, and therefore the detection of any departures from the uniform Hubble flow required a cause, such as the gravitational attraction of a supercluster of galaxies. To explore this fascinating hypothesis, a group of astronomers who came to be known as the Seven Samurai formulated a new method for determining the distances to elliptical galaxies, which they applied to a huge survey of more than four hundred galaxies.

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They found that the streaming motion of ­these ellipticals, over and above the Hubble expansion, was best fitted by a flow ­toward a “­Great Attractor”—­ that is, a concentration of galaxies in the direction of Centaurus twenty times more numerous than the Virgo cluster.19,20 Vera Rubin did not follow up on ­these spectacular developments. At first sight it may seem strange that, having launched a trendy field of observational cosmology, she declined to participate in it. We can only surmise that, having strayed into a controversial area of research on the dynamics of the universe, she found the rivalries and the intensity of the debates unattractive, and wished to get back into quietly investigating galaxies with their own characteristics and peculiarities. Vera liked to have a long-­term observing program with a clear-­cut objective. With two 4-­meter telescopes, complete with image tube spectrographs, available for her to use, a systematic study of the internal dynamics of individual galaxies was more appealing to her. What did become of the Rubin-­Ford effect? By the early 1990s, it was clear that, despite all the precautions, the data set was compromised by a subtle bias effect with its roots in the authors’ reliance on galaxy magnitudes from cata­logs, and the assumption that ScI galaxies shine, near enough, with the same intrinsic brightness.21 Nevertheless, reviewers and historians of astronomy give credit to Rubin, Ford, and their collaborators for their pioneering contribution. As Sandra Faber put it in 2016, subsequent work “demonstrated that such studies are in fact highly complex, and this first value obtained by Rubin and colleagues is only marginally consistent with ­later values. Nevertheless, their paper boldly opened the subject, and large irregularities in the cosmic expansion are now part of standard cosmic lore. Indeed, they are induced by the much greater masses of superclusters of galaxies due to their large dark m ­ atter components.”22 Leaving o­ thers to pursue the issue of how galaxies are moving over and above the steady expansion of the universe, Vera’s chief proj­ect between 1977 and 1984 was comparing the rotation curves of spiral galaxies with the three dif­fer­ent basic shapes that Hubble called Sa, Sb, and Sc (see Chapter 9). All the ones she studied w ­ ere isolated “field” galaxies. It was a deliberate strategy. ­There could be ­little doubt that galaxies packed into clusters are affected by their close neighbors and she ­didn’t want the galaxies’ environments adding confusion to her comparisons. She had established that the rotation curves of isolated field galaxies spanning a vast range of sizes have nearly identical shapes, and it followed that their mass distributions could not be inferred

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from physical appearances. Vera and David Burstein (one of the Seven ­Samurai) ­were confident “that field spirals are embedded in halos of ­little luminosity.” But would the same conclusions hold for spiral galaxies in densely populated clusters of galaxies? ­After all, their environmental history had been very dif­fer­ent. ­Giant elliptical galaxies ­were not uncommon, tidal interactions between pairs w ­ ere much more likely, and galactic cannibalism could have occurred. In such a melee, “Galaxies might have been stripped of their halos.”23 By 1986, Vera was committed to making a comprehensive study of the rotation curves of galaxies in clusters and groups. This investigative proj­ect, her main one for the next few years, resulted in several influential papers comparing and contrasting the properties of cluster members with ­those of isolated galaxies. S­ he’d made a head start in 1981 and 1982 by collecting spectra of twenty-­one spirals in four large clusters, while working at the 4-­meter telescopes at Kitt Peak and Cerro Tololo observatories on the program to observe isolated galaxies.24 She and her colleagues found that the shapes of the rotation curves of cluster spirals superficially resembled ­those of field galaxies. Nevertheless, a deeper statistical analy­sis disclosed that mass in cluster spirals is distributed differently than in field galaxies. Vera and her team suspected that the environmental conditions in clusters w ­ ere the cause.25 Further research into that question and the preparation of two major papers took almost two years. The first report, on the shapes of the rotation curves, concluded that “Cluster galaxies which appear normal are likely to have rotation curves that are indistinguishable from their counter­parts in the field; galaxies which appear peculiar are likely to have peculiar rotation curves. The most common peculiarities are falling rotation curves.”26 The companion paper revealed that belonging to a cluster, and especially being in the densest part, influenced how much dark ­matter an individual galaxy harbors. Galaxies near to the center had rotation curves that ­were declining with distance from the galactic center, which illustrated that their surrounding halos must be less massive and not as extensive as t­hose of galaxies in the cluster fringes or outside clusters.27 Vera’s study of the dynamics of both field galaxies and galaxies in clusters had certainly provided ample evidence for the presence of dark m ­ atter and the impact on galaxies of their environment, but her intention of studying in detail what was happening with galaxies in crowds had been defeated by the complexity of large clusters. Ideally, she needed a more tractable proj­ect

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Fig. 10.1 Vera Rubin and Kent Ford at DTM in 1988. (DTM, Car­n e­gie Institution of Washington)

for probing the distribution of dark m ­ atter around galaxies in close proximity. She alighted on the idea of systematically surveying the interactions between galaxies in tight compact groups with just a handful of members. For a handy list of such groups she could turn to The Astrophysical Journal to find one that Paul Hickson of the University of British Columbia had already compiled.28 Hickson’s attentive scrutiny of the Palomar Observatory Sky Survey prints enabled him to curate a sample of one hundred compact groups. All w ­ ere isolated and of very compact appearance, with four to eight members. It was a list from which Vera could pick and choose with confidence as Hickson had paid ­great attention to ensuring an unbiased sample for his study of their properties. Vera designed an observing program stretching over four seasons (from 1984 through 1987) focusing on twenty of the groups she deemed to be suitable for her study of their dynamics. Deidre Hunter, a postdoctoral fellow at DTM who moved to Lowell Observatory in 1986, participated in the program with Vera and Kent Ford. Images of each group ­were taken with

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a 0.9-­meter telescope at Kitt Peak, and spectroscopy was done mostly with the Palomar 5-­meter (200-­inch) telescope. The detailed and comprehensive analy­sis of the data occupied Vera u ­ ntil 1990. One compact group with seven members (Hickson 31) was so remarkable that Vera released the details as quickly as pos­si­ble in a short paper. Two of its galaxies appeared to be interacting and becoming entwined. The central regions of the pair w ­ ere blazing with a stupendous amount of ultraviolet radiation, being emitted by enormous numbers of massive hot stars that had formed only a few million years e­ arlier. Vera and her two colleagues had discovered two young starburst galaxies that w ­ ere colliding, spewing out faint wisps and tails of ­matter as they did so. The speeds with which the galaxies in this small compact group w ­ ere falling together indicated that they w ­ ere coalescing into a single entity. Hydrogen gas clouds w ­ ere being funneled ­toward the center, fueling intense star formation. “More than any other Hickson which we have studied,” they wrote, “H31 offers impressive evidence that it is in the pro­cess of becoming a single galaxy.” 29 The comprehensive paper that came out of the w ­ hole study presented detailed descriptions and many pages of photo­graphs of thirty-­t wo spirals in twenty-­one groups. One-­third had normal velocity patterns, one-­third yielded distorted or abnormal rotation curves, and one-­third w ­ ere too irregular for drawing any conclusions. The paper clarified the role of dark m ­ atter in compact groups of galaxies. It appeared that “the dark m ­ atter . . . ​is not clumped about each spiral and is likely to be a common intergroup background.” Three galaxies showed evidence that their halos had been stripped away. An impor­tant finding was that the quantity of dark ­matter associated with the spiral galaxies in the groups was only about half the amount found around field spirals. This raised the question of where the dark ­matter lurked in clusters of galaxies as a ­whole, if ­there was less of it clumped around spirals. Comparing the appearance of the group spirals with their sample of run-­of-­the-­universe field galaxies, Rubin, Hunter, and Ford saw that “galaxies in compact groups are reasonably similar to t­ hose in the field, but with some differences.” Th ­ ose differences they put down to forceful mutual encounters. ­A fter six years of observing and analyzing Hickson groups, they concluded that “galaxies in compact groups w ­ ill merge to form 30 a single elliptical remnant within a few orbital periods.” From the early 1970s, Vera’s abiding enthusiasm for observing galaxies, and the sheer fun she experienced from forensic analy­sis of the data, produced a

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Fig. 10.2 A cartoon depicting Vera Rubin by Dean Vietor (1931–2007), drawn on a paper napkin at a dinner in 1974 and presented to her at the time by the artist. The dinner may have been when Rubin gave a Smithsonian Astronomy Lecture. Hundreds of Vietor’s cartoons appeared in the New Yorker and many other publications. (Rubin ­f amily)

steady stream of short papers on vari­ous miscellaneous galaxies of types excluded from her program on the rotation curves of normal spirals, including barred spirals. A few examples illustrate the range of dif­fer­ent galaxy types that captured her interest. In September 1974, Vera guided the 2.1-­meter telescope at KPNO onto NGC 6764 to take spectra of this previously unstudied barred spiral galaxy in which the small bright nucleus is embedded in a central bar. While on an observing run for five nights, Vera and Kent Ford managed to get nine spectra, all but one centered on the almost star-­like nucleus of NGC 6764. Hydrogen clouds ­were revolving rapidly around the center, with evidence of both expansion and contraction motions. This was an exciting moment: Vera identified NGC 6764 as a Seyfert galaxy, a type of spiral galaxy with an active nucleus.31 At the time, astrophysicists who specialized in high-­energy phenomena in the universe w ­ ere puzzled by the incredible outpouring of energy from quasars and active galactic nuclei. The accretion of m ­ atter by supermassive black holes became the leading candidate for the “central engine”

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of quasars and Seyfert galaxies. It took just three years for clear observational evidence supporting this idea to emerge from a study of M87, the elliptical galaxy at the center of the Virgo cluster.32 The results from Vera’s next encounter with a Seyfert—­NGC 5506—­were published in 1978. She estimated that it had a mass of a hundred billion solar masses, “well within the range of normal Seyfert galaxy masses.”33 The central bar of some spiral galaxies is encircled by a symmetrical ring. One of the nearest examples is NGC 3351 (M95), an attractive face-on spiral and a firm favorite with amateurs b­ ecause its beauty can be enjoyed through a small telescope. On long exposure photo­graphs, the feathery ends of the two spiral arms merge and form an outer ring. Vera’s attention, though, was drawn to an inner ring of emission regions nestling within the central bar. Between November 1969 and May 1975, Team Rubin observed the central region of NGC 3351 on ten occasions to investigate the motions of its gas and stars. The big surprise was that the ring was both rotating and contracting. “In NGC 3351 we observe a rotating, contracting nuclear ring; we are unaware of any other galaxy with a similar feature” they wrote, concluding that they w ­ ere extending their study to the outer regions of the galaxy.34 A l­ittle over a year l­ater they confirmed, among other results, that the nuclear ring was contracting at 34 km / s while its glowing gas clouds, located approximately 340 parsecs from the center, ­were swirling around at a speed of 126  km / s.35 Some forty years on from this research, we now know that gravitational collapse along the circumference of the inner ring triggers ­giant gas clouds to form, which in turn become hot spots of intense star formation. Some of the gas escaping the circumnuclear ring is cascading ­toward a supermassive black hole and fueling the active galactic nucleus.36 Vera was the first spectroscopist to detect this streaming motion in the nuclear region of NGC 3351. Eigh­teen months l­ater, she and her team reported similar nuclear activity in the barred spiral NGC 5383.37 It ­wasn’t long before they added a third example, NGC 5728. By this stage, sufficient rotation curves of barred spirals existed for her to draw a striking conclusion: “Beyond their central regions barred spirals rotate with constant angular velocity, while non-­barred spirals rotate with constant circular velocity.”38 It amounted to confirmation of a theoretical model published in 1963 by Leon Mestel.39 On December 11, 1987, it took Vera Rubin and Jeffrey Kenney of Yale University only half an hour to obtain the spectrum of NGC 4383 in the

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Fig. 10.3 NGC 3351 (M95). This barred spiral galaxy was the subject of two papers by Rubin, Kent Ford, and Charles Peterson, published in 1975 and 1976. (ESO)

Virgo cluster of galaxies. This marked the start of their three-­year collaboration on rotation curves of about a hundred spiral galaxies in the Virgo cluster. Such an extensive program had been made pos­si­ble by the introduction at Palomar of a highly efficient CCD (charge-­coupled device) camera, which had already imaged spectra of the most distant galaxies then known.40 Vera, as a staff member of the Car­ne­gie Institution of Washington, had privileged access to the 60-­inch (2-­meter) and 200-­inch (5-­meter) telescopes, where she spent twenty-­eight nights productively observing fifty-­six Virgo cluster galaxies. Spectra of a further thirty-­three galaxies resulted from seven

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Fig. 10.4 A supreme example of Vera’s doodles, prob­a bly done sometime in the 1990s. Vera was an inveterate doodler when speaking on the telephone, usually drawing stylized galaxies. The name “Maxine” near the top refers to Maxine Singer, the distinguished molecular biologist and friend of Vera who was president of the Car­ne­gie Institution 1988–2002. (DTM, Car­ne­gie Institution of Washington)

nights of observing in 1989 and 1990 at Kitt Peak, where her program was allocated time on the 4-­meter telescope. She prepared for the observing with a clearly defined motivation and goal: “The Virgo cluster is not yet in overall dynamical equilibrium.” Galaxies in the cluster’s core ­were subject to the enormous environmental stresses of tidal interactions, multiple mergers, and mass transfer of gas by accretion and halo stripping. Th ­ ere was a huge amount still to be learned about “the precise evolutionary effects on the disturbed galaxies.” The answers that emerged from analy­sis of the CCD spectra revealed not only the forms of their rotation curves, which gave the mass distributions, but also the motions of the galaxies’ stars and gas in their nuclear regions.41 One of Vera’s papers on the Virgo cluster opens with beguiling simplicity: “Centers of galaxies are still mysterious places.” Precisely for this reason, she

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had been delighted to find that she could probe in some detail the complexities of the structures, motions, and even chemical compositions in the innermost regions of many individual galaxies in this very nearby cluster. Although she started out with the idea of examining the properties of the cluster as a w ­ hole, learning what she could about the workings of individual galaxies was an irresistible spin-­off from the main program. Following her success with the circumnuclear ring of NGC 6764, she identified fourteen galaxies, half of them barred spirals, with an in­ter­est­ing spectral signature: gas whirling about the nucleus at high speed.42 Vera and her coauthors deduced that each had a small gas disk extending some 400 to 800 parsecs from its nucleus and they suggested that gravitational interactions had funneled gas ­toward the nucleus, where it had settled into a distinct disk. It was likely that up to half of the bright galaxies of the Virgo cluster could have features of this kind. The combined mass of the disk and nucleus ranged from 1.5 to 14 billion solar masses in the sample of fourteen, which made two of them—­NGC 4216 and NGC 4526—­large enough to harbor supermassive black holes.43 In thirteen of the galaxies observed, the inner gas disks rotated in the same direction as the outer disk of stars. But what of the ­fourteenth, NGC 4550? It turned out to hold a secret of the universe. But first, Vera had to find the key to unlock the greatest surprise of her c­ areer as an astronomer. NGC 4550 is a normal-­looking galaxy near the center of the Virgo cluster. When Vera obtained a spectrum in 1989 at Palomar, she was the first professional to do so since 1956.44 The moment she looked at the spectrum she realized it was a rare beast. Its absorption lines revealed a normal pattern of rotating stars, but the bright emission line of hydrogen showed that the gas rotated in the opposite direction. About a dozen examples of spirals with contrary rotation of the gas disk w ­ ere already known. Theorists readily explained the phenomenon as a consequence of two galaxies interacting, with one capturing additional gas from the other: computer modeling had shown exactly how it could happen. In the case of NGC 4550, however, a curious diamond pattern traced by the absorption lines in the spectrum r­ eally unsettled Vera. She oscillated for about two years between believing and disbelieving that each absorption line was double, and she was thinking about securing more spectra. Then, “One day I just de­cided that I had to understand what this complexity was,” she told interviewer Carol Mockros.45 “I made sketches on a piece of paper and

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suddenly I understood it all. I mean I have no other way of describing it. It was exquisitely clear.” Three strong lines due to the ele­ment magnesium held the key. Vera had worked out the pattern the three lines would form on her spectrum if half the stars rotated one way, and the other half in the opposite direction. And ­there it was. She had reproduced the diamond pattern—­and she asked herself why she ­hadn’t done it two years ­earlier. “This was an exciting moment” she ­later recalled.46 But was it physically pos­si­ble to have stars rotating in opposite directions and intermingling? She delved into the lit­er­a­ture to see what she could find. ­There was one paper she had noticed in 1960 and had never forgotten. It was written by Donald Lynden-­Bell, who had shown that a hy­po­thet­i­cal s­pherical cluster of stars in which half the stars go into reverse is dynamically stable.47 No one had i­ magined, however, that such a system could ­really come into existence in nature. Vera was only the ninth author to cite the paper, and the first to do so in the context of an empirical observation!48 For Vera, her “two-­way galaxy” was an “enchanting” discovery and she loved to talk about it. The episode epitomized why she found her kind of astronomy fulfilling. She could look back on it and say, “It is enormously satisfying to have the eye of the observer rewarded occasionally with a view of a former secret of the universe.” 49

CHAPTER 11

SPEAKING OUT FOR ­WOMEN

A

s the clattering of dishes died away, the chattering guests around the conference dinner t­ ables fell s­ ilent too, and looked t­ oward Vera Rubin, who had stood to give the first of two after-­dinner talks. For a gathering of physicists, it was a somewhat unusual mix. Of the 148 participants attending the two-­day conference in early November 1990, all but 19 w ­ ere female. The event was a workshop in Chevy Chase, Mary­land, on “The Recruitment and Retention of ­Women in Physics,” cosponsored by the American Association of Physics Teachers, the American Institute of Physics, and the American Physical Society, and the drift of the discussions during the day had raised some disturbing issues. Every­one had been talking about the “chilly climate” for w ­ omen in physics on college campuses.1 Now, though, they looked forward to two motivating talks that promised a more cheerful end to the day. The first of the ­women they ­were about to hear had for twenty years campaigned tirelessly to warm up that climate, and urged w ­ omen scientists to persevere and support each other. The second speaker was the first speaker’s d ­ aughter: Judy Young, an award-­winning young professor of astronomy at the University of Mas­sa­chu­setts.2 In her address, Vera shared with her audience three assumptions at the foundation of her philosophy: • ­There is no prob­lem in science that can be solved by a man that cannot

be solved by a ­woman; • Worldwide, half of all brains are in w ­ omen; and • We all need permission to do science, but for reasons that are deeply ingrained in history, this permission is more often given to men than to ­women. By “permission” Vera meant that, to make a ­career in a field, a person had to have doors opened along the way that ­were closely guarded by gate-

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keepers: parents, school teachers, college officials, funding officers, mentors, and colleagues.3 She had heard countless stories from other ­women about attempts to discourage them. “Go and find something ­else to study,” one department chairman told a gradu­ate school entrant. “Why ­don’t you just go off and get married?” suggested a counselor to a student who had gone for advice on a prob­lem. “I’m not g­ oing to sea with a girl on my boat,” a sailor had protested when he learned that a w ­ omen oceanographer would be aboard.4 Vera had experienced such prejudice herself, of course. “You should do OK as long as you stay away from science,” her high school physics teacher had counseled, having ignored the girls in his class. “We d ­ on’t admit ­women to the gradu­ate school in astronomy,” was the reply when she inquired at Prince­ton University. A Cornell professor had informed her that, naturally, it would be he who presented her work at the AAS meeting. While she was a student, and in the early years of her c­ areer, Vera focused on navigating her own way through this minefield. She juggled the demands of looking ­after young c­ hildren and challenges of a ­career in astronomy and gave ­little thought to the idea that she might be instrumental in removing the kinds of barriers she was encountering. At that time, w ­ omen could do ­little more than work within the system and grasp what­ever opportunities existed. She ­wasn’t alone in taking this line. Her contemporaries had endured comments similar to t­ hose Vera had heard, like “the director ­didn’t want to take a chance on a w ­ oman,” and assumptions that they would work, perhaps part-­time, ­until they started a ­family. “Amazingly most of us accepted this attitude as normal even though we resented it,” recalled one w ­ oman who had been a gradu­ate student in the 1960s.5 A letter in July 1964 to Vera from William C. Kelly, director of education and manpower at the American Institute of Physics (AIP), may have been the first communication to make Vera aware she was in a position to make the experience dif­fer­ent for ­women who followed. Kelly was blunt about the barriers in the way of girls and w ­ omen. “I need not tell you,” he wrote, “that even the very able [girls] face social opposition to c­ areers in physics, and it requires all of their determination to succeed.” The AIP was proposing to arrange visits by ­women physicists to “strong academic high schools” to impress on girls that w ­ omen could be successful in physics. Would Vera be willing to participate in this program? Kelly also invited her views on other ideas for encouraging more w ­ omen to pursue ­careers in physics.6

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Enclosed with the letter was a printed booklet, produced by the AIP in 1962 with the intention of making physics attractive to more girls. Its introduction declared that it would pre­sent a realistic picture of both the opportunities and the prob­lems for w ­ omen. Although the author was a ­woman, Dr. Elizabeth A. Wood of Bell Telephone Laboratories, the message was clear: w ­ omen physicists would be accepted only if they stayed single and acted tough. Wood wrote: ­ fter having trained three successive girls as laboratory assistants, only to have A each one leave to get married, one research scientist fi­nally said he would not accept another girl as an assistant, no ­matter how good she was. He just could not afford the time required to repeat the training period. That is not prejudice, that is learning from experience. Some w ­ omen are supersensitive. Once a man has had a w ­ oman shed tears in his laboratory, he ­will do every­thing he can to avoid repeating the painful incident. A research physicist who had had this experience said, “It was awful. I ­didn’t dare ask her to do anything for fear it would upset her.” That is not prejudice, that is learning from experience. On the other hand, a girl who is a good sport and does a workmanlike job along with the rest of her colleagues w ­ ill be treated on an equal footing with the men, and she ­will be paving the way for other w ­ omen physicists.7

­There is no hint ­here that the w ­ omen who left their jobs ­after marriage might have been forced out by rules that forbade a husband and wife to work in the same laboratory, or that the upset ­woman might have been reacting to sexist be­hav­ior or harassment. ­There was no suggestion that men should change their attitudes and be­hav­ior. ­These ­were all issues about which Vera would speak out a few years ­later but, at this time, her response to Kelly, although muted by her strong commitment to f­amily life, was positive. “As you can well imagine,” she confessed frankly, “I am reluctant to add other duties to my busy days, but I would be willing to do so for any program you could develop.” Although Vera had spoken in schools in the Washington area about her research on the Milky Way, she noted t­ here had “never been any contact with teachers or principals, or any discussion of science teaching, ­women in science, or the like.” Vera did not refer to the ­careers brochure in her reply but did volunteer what she thought girls should know: that ­women scientists are normal ­people who have ­family lives as well as ­careers, and are not mannish ­women de-

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ciding to go through life as honorary men. “I do won­der if some girls might not be more interested in the personal side of the life of a ­woman scientist than in her scientific achievements,” she wrote. “Perhaps the facts that I have a physicist husband, four ­children who are outstanding in many activities, and who ­were raised by me (with constant help from my husband), that I do all my own cooking, shopping ­etc., and that almost all our vacations, with the c­ hildren, consist of attending scientific meetings would be of more interest than hearing a scientific talk or of knowing the number of papers which I have published. We lead a very busy, very stimulating, never dull life.” ­There is no rec­ord of what, if any, school visits Vera made as a result of the AIP initiative but, over the next several summers, she found time to give talks to young p ­ eople at the American Museum of Natu­ral History in New York. She also made a two-­day visit to Vassar in 1967 to give talks and lectures. The dormant seeds of indignation within Vera ­really began to awaken in the early 1970s. By then she was in her early forties and established in her ­career, with a growing reputation both for her scientific work and for her willingness to take on administrative responsibilities in the academic world. If Vera agreed to join a board or a committee, she took the role seriously, and was always buzzing with creative ideas. For some thirty years, u ­ ntil she was in her early seventies, she was usually a member of at least four boards or committees at any one time. While browsing through the prestigious journal Nature in 1970, Vera alighted on an advertisement for an ecologist, placed by the Australian national research organ­ization CSIRO. She was not about to change her academic field, but ­there was a sentence in the advertisement that caught her attention: “Salary rates for ­women are $A428 p.a. less than the corresponding rates for men.” She circled it in red ink. How could such unfairness be justified in 1970? Ranting was not Vera’s style. She preferred to point out, with her characteristic irony, that having dif­fer­ent pay rates for men and w ­ omen was illogical. She replied not to CSIRO but to the editor of Nature, John Maddox. If she could get a letter published, many more ­people would see why paying ­women less was not just unfair but contrary to common sense, and t­here was a chance of starting a public debate. She wrote: I have read with interest your recent advertisements offering lower pay to females than to equally qualified males. In as much as e­ very scientific director ­will surely hire, of two equally qualified applicants, the one asking for the

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lower salary, such policies clearly discriminate against male applicants. In an effort to reduce this male discrimination, I suggest the following courses: 1. All applicants sign their applications with first initials only, hence allowing no differentiation by sex; 2. All male applicants demand a lower salary, thereby making them just as desirable as female applicants; 3. NATURE discontinue such discriminatory advertisements.8

Maddox’s reply was brief and dismissive. “Thank you for your in­ter­est­ing letter. We are for the ­women’s liberation, but not all our readers share your views.” The editor of Nature was more concerned about the circulation of the journal, and no doubt the advertising income, too, than standing up against discrimination—or even permitting a debate in his journal’s august pages.9 Just one year ­later, t­here was an incident that made Vera realize that fighting discrimination against w ­ omen in astronomy, and in science more generally, was a mission she must embrace ­wholeheartedly. It had not been so long since Rosa Parks had famously refused to give up her bus seat to a white passenger in Montgomery, Alabama, in 1955, and had set off a chain of events that resulted in segregation on buses being declared unconstitutional. Now, Vera saw a single act of protest by a courageous ­woman make a difference in her own field. Margaret Burbidge, reacting to what, in her eyes, amounted to discrimination, de­cided to launch an assault against complacency in the astronomy community, both in the United States and beyond. By snubbing the American Astronomical Society (AAS), Margaret forced its hand and triggered a chain of events that would cause many astronomers, both male and female, to change their attitudes about discrimination on grounds of sex. The AAS had nominated Margaret Burbidge as the 1971 recipient of its Annie J. Cannon Award, a prize endowed in 1933 by the distinguished Harvard astronomer Annie Jump Cannon, who had wanted to advance astronomical research by ­women. The rules stated that the cash prize, from the income of the fund, be awarded at intervals of at least two years, and always in recognition of a ­woman’s impor­tant work in astronomy. Margaret declined to accept it. “Much as I appreciate this honor,” she informed the AAS, “I believe that it is high time that discrimination in ­favor of, as well as against ­women in professional life be removed, and a prize restricted to w ­ omen is in 10 this category entirely.”

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The Annie J. Cannon Award was the first of the AAS awards to be established and had been given e­ very three years since 1934, so that a dozen w ­ omen astronomers had so far been honored. Since then, the society had a­ dopted two further honors, each to be awarded annually. Of ­these, t­ here had been only one female recipient—­and she only jointly with a male colleague. That winner was Margaret Burbidge, who along with her husband, Geoffrey, had won the 1959 Warner Prize, given to early c­ areer astronomers. Th ­ ere was a widespread perception among ­women that they ­were competing in a separate category with each other, as if their contributions to research ­were not comparable to ­those of men. Margaret Burbidge’s protest sent shock waves through the AAS. She was held in high regard and the Council of the Society (which included Geoffrey Burbidge at that time) took her seriously. It considered her reasons for declining to be “of such general weighty character that the Society should consider them thoroughly before taking further action.” A special committee was appointed, chaired by George Preston, to assess the options and make recommendations about the f­ uture of the Cannon award. The other members ­were four w ­ omen and two men: Anne Cowley, Helen Sawyer Hogg (who had received the Cannon award in 1949), Roberta Humphreys, Sidney Wolff, William Liller, and Benjamin Peery.11 In August 1971, all AAS members “with strong and thoroughly considered opinions in this ­matter” ­were urged to write to the chair.12 Vera most certainly had strong and considered opinions. In fact, she had been disturbed by the lack of ­women among the officers and council of the AAS for some months. She had spoken about this issue to Bart Bok, a member of the council whose wife, Priscilla, was also an astronomer and his close collaborator. Bok had urged Vera to put her concerns in writing at that time. Vera had hesitated to make waves, however, uncertain that she had the standing to speak out on a potentially controversial issue. Initially, she had thought her complaint “was not a major one” and she did not want to annoy the officers of the AAS, all of whom, she was sure, ­were “working for the good of all astronomers.” But now, Margaret’s action had created for Vera “a legitimate forum” for expressing her concerns, in the shape of the special committee, and she de­cided to speak freely.13 It was just the encouragement Vera needed to go public with her honest opinions. Her campaigning for the equality of ­women and men in astronomy and other sciences effectively began h ­ ere, and would continue for the rest of her life.

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In Vera’s view, the Cannon prize should be retained but be open to both men and w ­ omen. Her reasoning was ­simple. “This would dispel the implication that a female astronomer is worthy of a prize only in comparison with other females.” But then she went further, suggesting that the committee go beyond its formal remit to make recommendations on the Cannon prize: Additionally, I would like to ask that your committee enlarge the scope of its concerns to include the position of ­women astronomers in the Society. For example, could you suggest that a ­woman always sit on the committee which ­w ill choose the winner, even though the winner might generally be male? Such concern is warranted, I believe, ­because at the pre­sent time w ­ omen astronomers have zero repre­sen­ta­tion in the American Astronomical Society slate of officers and council. In the last election, all nominees for all positions ­were male. Could you request that the nominating committee place the name of at least one female astronomer on the ballot? Surely, if the AAS is sufficiently concerned about the repre­sen­ta­tion of young astronomers to invite three of them to sit in on council meetings, it should be equally concerned about the repre­sen­ta­tion of ­women astronomers. It should not be necessary for ­women astronomers to have to resort to gathering signatures to place a female nominee on the ballot.14

According to Roberta Humphreys, who served on the special committee, t­ here was no consensus about the award within the committee. Two of the ­women wanted to open it to both men and ­women or abolish it. The other two wanted to keep it as it was or abolish it. And the three men “sat on the fence.” To be sure, t­ here was also the l­egal issue of the terms of the original bequest, which could not be ignored. When one council member, Donald Osterbrock, de­cided to consult Vera by letter before making up his mind, Vera responded at length, detailing a reconsidered position: It would be a ­mistake, I think, to continue the prize as it is. It would also be am ­ istake to discontinue it. Both of ­these actions would imply that the AAS is unwilling to face the prob­lem and do anything about solving it. If the prize ­were offered to me ­under the pre­sent conditions, I would not accept it. And that is a hard sentence to write, and one that has been painful to arrive at. Yet I think I would be turning my back on pro­gress within the Society and the needs of the ­f uture female astronomers, if I did nothing to help change the situation. . . . ​W hat looks like the best course to me is something like the following. Continue to limit the prize to w ­ omen but upgrade the prize completely to the level of the Russell Lecture. . . . ​In addition, what I would most like is a statement from the Council that in restating the conditions of this

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award, the Council recognizes its obligation to work for the integration of ­women astronomers into the Society, by considering them for positions on Society committees, by asking them to give invited papers, even perhaps by asking that prominent gradu­ate schools do away with discriminatory admission policies t­ oward w ­ omen.15

In the end, the compromise recommendation, accepted by the AAS in 1972, was to keep the award as one for w ­ omen but to limit it to nominees in the early stages of their ­careers. The AAS then further distanced itself from the women-­only prize by transferring its administration to the American Association of University W ­ omen. Vera’s d ­ aughter Judith would go on to win 16 it in 1982. The committee had less difficulty with its second recommendation. Having listened to Vera, it reached a consensus: “The prob­lem of ­women in professional life transcends the disposition of the A. J. Cannon award, which is only the tip of the iceberg. We recommend that the AAS sponsor a working group.” This, too, was accepted by the council, which appointed a steering group to coordinate the contributions of a number of volunteers. Its members ­were Anne Cowley as Chair, Roberta Humphreys, Beverly Lynds, and Vera Rubin. They w ­ ere given a year to report back. Vera had set out her stance in the long letter she wrote to Osterbrock, warning him from the start that what she wrote was “very personal,” and yet she c­ ouldn’t “help but think that it reflects the views of many w ­ omen astronomers.” She then opened up: I “do” astronomy to get answers, get data, learn. If I am ­doing this, I am content. Recognition is decidedly secondary. Almost all of my time, I am absolutely contented as an astronomer, as a ­woman, as an AAS member. Only very occasionally does something occur to infuriate me, and ­really set me off on the “female lib” track. I say this at the outset ­because all of my complaints, e­ tc., should be understood in this light—­not a major part of my life, but the intellectual and emotional responses to a prob­lem, when I stop to think about it.

This assessment of herself would remain true, except that in practice, as time went on, “occasionally” changed to “often.” Next in the letter, she described to Osterbrock her feelings about the AAS before the Cannon award affair broke: About a year and a half ago, the AAS ballot came with about 33 names of committee members, council members, nominees for election, ­etc., ALL of

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them male. On the same announcement, the Council was noting that three young astronomers ­were to be asked to sit on the Council . . . ​A nd who was to represent the ­women? No one, and apparently no one cared. I wrote a furious letter to the AAS Council, which of course I never mailed.

Now, although her views on the award had changed somewhat since she had first written to the special committee a year ­earlier, her overall feeling was the same. “This prob­lem . . . ​should be used as an opportunity for the Society to make a step t­owards improving the status of ­women within the Society.” In eleven meetings she had attended over the previous seven years, ­there had been forty-­five invited talks, not a single one given by a ­woman. The society should ensure that ­women participate in nonelected offices, she believed, given that their smaller circles of professional contacts made it harder for them to be elected.17 The working group beavered away, collecting facts and opinions from a wide range of sources. Vera played a major role in drafting the final report, which was delivered in 1973 and formally published the following year. It contained a wealth of detailed statistics to support the unsurprising conclusion that “­women astronomers face greater obstacles in almost all aspects of their professional c­ areers than do their male counter­parts.” The AAS Council unanimously accepted the report and ­adopted its recommendations.18 It was quite an achievement. The professional “establishment” had very publicly endorsed the concept that “the astronomical community can only be enriched by the employment and ac­cep­tance of ­women as colleagues.” But the issue was far from over, as Vera knew only too well. It was only a start. Meanwhile, very likely inspired by Margaret Burbidge’s rejection of the Cannon award, Vera had staged a protest of her own. As she had told Osterbrock, if something infuriated her it could r­ eally set her off “on the ‘female lib’ track.” And she had seen that challenging inequity could produce results. Now sensitized to discrimination against ­women wherever she saw it, Vera took on one of most venerated bastions of male exclusivity in Washington, the Cosmos Club. Founded in 1878 as a gentlemen’s club, it had always drawn its membership from among the most distinguished men in the arts and sciences, learned professions, and public ser­vice. Since 1952 it had occupied the sumptuous Townsend Mansion on Mas­sa­chu­setts Ave­nue.19 Adjacent to the mansion, the club has an auditorium, with its own entrance, and it was ­here that the Philosophical Society of Washington (PSW) held

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its regular meetings. Bob Rubin was a member of the PSW and in 1972 was the corresponding secretary of the society. Bob and Vera w ­ ere well aware that the Cosmos Club did not elect w ­ omen as members. It was not alone. At that time, many men-­only clubs had not changed their policy. W ­ omen guests ­were allowed inside the Cosmos Club but ­were forbidden from crossing the threshold of the main front door. Female visitors ­were required to enter through a back door, called the “Ladies’ Entrance,” which was near to the auditorium entrance. It was this rule, which Vera considered insulting to ­women, that incensed her even more than the fact that the club was all male. In May 1972, Vera wrote to Philip H. Abelson in his capacity as president of the Car­ne­gie Institution of Washington on what she calls this “non-­ trivial ­matter,” suggesting that neither he personally nor the institution use the facilities of the Cosmos Club u ­ ntil it changed its policy. The dart was well aimed; Vera could not have been unaware that Abelson happened to be president of the Cosmos Club’s board of management at that time. Her language is firm but not intemperate: As long as the Cosmos Club refuses to allow w ­ omen guests to enter by the front door, the Car­ne­gie Institution should not support such discrimination. I assume that the Car­ne­gie Institution would not make use of any facilities which would require the use of a side door for any racial or religious group, yet the insult to w ­ omen guests at the Cosmos Club is no less severe. As a member of the Car­ne­gie “­family,” I am uncomfortable for any ­woman guest of the Institution who is subjected to such practices.20

Abelson w ­ ill not be drawn into a discussion. His reply thanks her for her letter, and concludes: “You w ­ ill be interested to know that the Board of Management of the Cosmos Club has ­under consideration a change in policy with re­spect to the entrances to the Club.” In fact, the club was already u ­ nder pressure—­not least, from some of its own members, such as the distinguished international ­lawyer Stephen M. Schwebel, who had made numerous attempts to get the entrance policy changed. Success came only a­fter the American Society of International Law de­cided to stop holding meetings at the Cosmos Club and not to use it for lunches and dinners. The bylaws w ­ ere fi­nally changed on January 15, 1973.21 A few months before that happened, and shortly a­ fter she had written to Abelson, Vera was invited to speak at a meeting of the PSW on November 17,

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1972. It was customary for speakers to be entertained with dinner at the Cosmos Club and she received the invitation as expected. Was it a coincidence or did Bob have something to do with creating an opportunity for Vera to put the PSW and the Cosmos Club to the test? ­There is no way of knowing, especially as Vera was in any case an excellent speaker with in­ter­ est­ing research to report. Her topic was to be “More than you ever wanted to know about the Andromeda Galaxy.” Vera’s letter to the PSW turning down the dinner invitation was by this time entirely predictable. She would “no longer accept the discriminatory practice of being forced to use a special entrance.” She hoped her stance would “underscore the segregated nature of the facilities which the Society uses and the insult it imposes on all ­women dinner guests.” If the society had a prob­lem with her using the front door, then she suggested they choose somewhere e­ lse for dinner. And that is what happened.22,23 It was not the end, however, of the Cosmos Club story. The real ­battle was only just beginning, as professional ­women became more vocal about what they saw as the club’s obstinacy over admitting w ­ omen as members. The membership was split, but the conservative view prevailed. Some of ­those in ­favor of admitting w ­ oman resigned and o­ thers persisted in nominating ­women in defiance of the rules. Margaret Burbidge was nominated several times. Vera, along with many of her colleagues, regarded the Cosmos Club (and similar all-­male establishments) as discriminatory and hence unacceptable. It was as ­simple as that. The prob­lem was acute for professional w ­ omen ­because the Cosmos Club was, for historical reasons, so much at the heart of both social and professional networking in the academic, professional, and po­liti­cal communities of the federal capital. It offered a comfortable, congenial, and con­ve­nient location for a wide range of business meetings and events, and, if you ­were a member, desirable accommodation while visiting Washington. Although ­there was no restriction on who could attend events, the princi­ple that w ­ omen ­were excluded from the privileges of membership, and the networking that went on in the club, increasingly made ­women angry. It was symbolic of the entrenched attitudes still proliferating throughout society. The Cosmos Club eventually voted to admit ­women, but not ­until it was threatened with l­egal action u ­ nder Washington’s anti-­discrimination law in 1988 and faced almost certain defeat in court. Before that decision, Vera was

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involved in at least one further flurry of activity in the ­battle against the club’s discriminatory position. In 1981 she challenged John Teem, president of the Association of Universities for Research in Astronomy (AURA), over that organ­ization’s use of the club for its meetings. Vera wrote to him formally requesting that AURA refrain from using the Cosmos Club in any way.24 In this move she gained the support of Richard Henry, physics professor at Johns Hopkins University, and of Margaret Burbidge. Richard Henry wrote his own letter to John Teem: I remember how mad I was at Nancy Roman when she forced a relativity meeting, on short notice, to move from the Cosmos Club to NASA HQ, ­because of the policy of the Cosmos Club regarding membership by females. I had accepted the way the world was, ­because the world was that way. No longer! I ­won’t accept wrongs!

Henry stated unequivocally that he would now refuse to attend meetings at the Cosmos Club. He was “furious with them for continuing a policy which makes association with them impossible.”25 Margaret Burbidge was delighted to receive from Vera a copy of her correspondence with John Teem and replied to her approvingly: “Of course I agree with you.”26 Some months e­ arlier, Margaret’s name had again been put forward for membership by some members who supported admitting w ­ omen, in a bold attempt to force the issue back onto the club agenda. “I have stored up some wonderful quotes from the Washington Post!” Margaret exclaims. Perhaps she had in mind the reported view of all sixteen living former presidents of the club that admitting ­women would transform “one of the world’s distinguished men’s clubs into a mere luncheon group” and that “we are told, for no clear purpose, that times have changed since the Club was founded . . . ​ our knees are expected to jerk simply b­ ecause the buzz-­words are uttered—­ discrimination, exclusivism, elitism, anti-­feminism.”27 Meanwhile, pro­gress in the American Astronomical Society was slow despite the enthusiastic reception given in 1973 to the working group’s report. It was a further five years before the AAS appointed its ad hoc Committee on the Status of ­Women in Astronomy in 1978, with Martha Liller as chair. Vera was not a member of that committee but had been elected to the council for a three-­year term in 1977. The first job for the committee was to update the 1973 report. Its disappointing verdict was that the status of ­women in the AAS had changed very ­little. In response, the AAS agreed in 1979—no doubt with Vera’s encouragement—to establish a standing committee to

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drive change.28 This committee has remained active ever since. Vera never served on it, but her DTM collaborator Kent Ford and her ­daughter Judith Young ­were both appointed in 1982, and John Teem, whom Vera had lobbied over the Cosmos Club, became a member in 1983.29 If Vera did consider putting herself forward for the AAS Committee on the Status of ­Women, she prob­ably concluded that she had enough on her plate at that time, as she was accepting invitations to serve on a variety of professional boards and panels. Being highly critical of the poor repre­sen­ta­ tion of ­women on such bodies, she would hardly want to turn down the opportunities now coming her way. Pointing out gender imbalance wherever she found it in her professional encounters became one of the battlefronts where Vera kept up relentless pressure. Another was the use of language that does not pass the “gender-­neutral” test. Vera a­ dopted the precept that “we are what we say,” and, in a letter she submitted to the editor of the journal Physics ­Today in 1977, she explained her opinion on why that mattered.30 “What much of the scientific community appears to be saying to young w ­ omen is that it is male. If this appearance is to be altered, changes in language may have to lead the way.” Drawing on examples from personal experience to illustrate what she meant, Vera expressed “a gut fear that the capable, in­de­pen­dent self-­motivated ­woman,” the sort of person who should be encouraged to take up science, “is just the person who might object to the following,” as she offered a list of examples including ­these: • When

her papers submitted to The Astrophysical Journal ­were sent to referees, the accompanying form letter asked the referee to comment on “his work,” and referred throughout to the author of the paper to be reviewed as “he” and “him.” • Her work was discussed in a national magazine u ­ nder the title “Wise Men from the South Peer ­ toward What May be Limits of the Universe.”31 • When a distinguished scientist called board meetings to order, he made a habit of looking at her—­the only female member—­hard in the eye while firmly saying “Gentlemen.”32 Any organ­ization or publication Vera considered to be guilty of sexist language could now be on the receiving end of her censure, including her own employer. Writing to the Publications Office of the Car­ne­gie Institution of

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Washington in 1979, she attacked the “extreme masculine bias” she perceived in the section on postdoctoral fellows in the cata­log. She was particularly cross b­ ecause she and her DTM colleagues had pointed out precisely what amendments they deemed necessary when the 1978–1979 cata­log was published, and yet nothing had changed in the next edition. It would have been completely contrary to Vera’s character to give up. “What the Car­ne­gie Institution appears to be saying is that fellows are male,” she stated bluntly. “I hope very much that the entire cata­logue ­will be revised before the next edition to remove this bias. We at DTM had submitted such corrections for the previous edition, but they w ­ ere not incorporated. I regret this very much.”33 Vera’s uncomplicated view was that plural pronouns, such as they and their, are the acceptable gender-­neutral alternatives to he, she, his, and her. As a member of five-­years standing, she wrote to the National Acad­emy of Sciences in 1986, for example. “So this is my yearly letter on the use of personal pronouns by the NAS.” Vera was nothing if not per­sis­tent. “This year it is the use of ‘his’ and ‘him’ in the list of Awards for 1987 and in the booklet containing the description of the prizes. . . . ​Can we get rid of them? ­You’ve done a g­ rand job in the past, so I know you can.”34 Not every­one—­even among w ­ omen colleagues—­accepted this trend in En­glish usage. One such astronomer was V ­ irginia Trimble. Still hammering on with determination in 1992, Vera took issue with the Astronomical Society of the Pacific (ASP) for allowing an article by Trimble to appear in its Publications (PASP) despite its alleged “sexism.”35 She directs her anger at the journal’s editor, Howard Bond, rather than at Trimble: “This is not a new issue. ­Virginia and I have discussed it before, to no avail. But I have now concluded that the time has come to put a stop to it. And the ASP must take a part in ­doing so. Many of the PASP readers are ­women, and statements like ‘The reader is invited to conclude for himself that . . .’ are insulting, degrading and no longer acceptable, regardless of the sex of the author.’ ”36 Unsurprisingly, Bond passed the letter to Trimble for comment and the reply was a weary, good-­humored letter to Vera. Trimble was sorry if she had offended Vera, but “you know I f­avor traditional, dictionary En­glish, in which . . . ​as a guide for copy editors once phrased it ‘male embraces female.’ I wish very much that we could just agree to disagree on t­ hese points.”37 Eventually, Vera’s letter and V ­ irginia’s reply wound up on the desk of Bruce Carney, chair of PASP’s board of editors. Vera was gaining more

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Fig. 11.1 Vera Rubin’s induction into the National Acad­e my of Sciences in 1982. (DTM, Car­n e­gie Institution of Washington)

converts to her point of view. “Howard [Bond] is disturbed by the issue . . . ​ and I believe he w ­ ill be more careful in the ­future,” Carney assured Vera by way of conciliation: “My own opinion is that the offending phrases should have been changed. . . . ​To me the key is w ­ hether the readers are offended. You clearly w ­ ere by the male-­oriented language. I have asked my two w ­ omen gradu­ate students how they react to such phrases, and while they do not feel as strongly as you do, they admit to discomfort. . . . ​I conclude we should try to avoid gender-­oriented language whenever pos­si­ble.”38 Per­sis­tence was paying off. Throughout the 1980s, with her voice becoming ever more influential following her election to the prestigious National Acad­emy of Sciences in 1981, Vera intensified her fight for equal treatment of ­women. Her files bulged with correspondence, press cuttings, and newsletters. She was invited to serve on panels and committees, including the subcommittee on w ­ omen of the National Science Foundation’s Committee on Equal Opportunities, the American Physical Society’s Committee on the Status of ­Women in Physics, and the board of the Association for W ­ omen in Science.

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Vera’s concerns now extended beyond astronomy to the ­whole of science and wider society. On June 30, 1982, she went to work dressed differently than usual, in a white skirt and old green polo shirt. At 11:30, she left DTM and made her way to Lafayette Square, across from the White House, and joined a throng of similarly clad ­women for a rally sponsored by the National Organ­ization for W ­ omen (NOW), a movement dedicated to achieving full equality for ­women. Dressing for the meeting was to remind her to go. “Usually I get so involved in my work that I forget my social responsibilities,” she wrote in a letter she hoped might be published in The New Yorker.39 But this day was memorable, for midnight was the deadline by which thirty-­eight states had to ratify the proposed Twenty-­Seventh Amendment to the United States Constitution, known as the Equal Rights Amendment (ERA), to enable it to become law. Passed by the Senate and the House of Representatives in 1972, the ERA stated uncompromisingly that “Equality of Rights u ­ nder the law s­ hall not be denied or abridged by the United States or by any state on account of sex.” On the face of it, the ERA encapsulated a concept essential to social justice, and yet ­there ­were many, both men and ­women, who feared the consequences of upsetting established conventions. Even ­after an extension to the original seven-­year deadline, the tally of ratifying states was three short of the necessary total.40 As ratifications petered out and the initial 1979 deadline approached, the AAS was among many professional organ­izations that had refused to hold meetings in states that had not ratified the ERA. This was, however, a controversial decision. Margaret Burbidge was president of the AAS, having become the first w ­ oman to hold the office in 1976, and Vera had been elected to its council in 1977. Both strongly believed that the AAS should take a stand, while opponents protested that the society was straying too far from ­matters astronomical into po­liti­cal and social affairs. S­ houldn’t the society just be ­doing more to improve the situation of ­women astronomers—­starting with acting on the recommendations of its own 1973 report? That was a suggestion which every­one could embrace, and so the AAS’s Committee on the Status of ­Women in Astronomy came into being.41 The failure of the ERA was a b­ itter disappointment to Vera, but NOW and other ­women’s organ­izations ­were vowing that the fight would go on. Vera wrote, “the rally was pleasant; full of up-­beat forward looking phrases, lots of enthusiastic ­people, most in green and white, but mostly for me it was sad. I c­ ouldn’t forget that we w ­ ere t­ here b­ ecause we had failed.” Dismay

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over the ERA did not diminish Vera’s own resolve, however. It created all the more reason to do what she could as an individual. She pressed for change wherever she perceived discrimination. She was constantly on the alert for actions, however small in themselves, that might help change attitudes in society, and justified her suggestions with persuasive logic. Joan Callanan, coordinator of the ­Women in Science programs of the National Science Foundation (NSF), was a recipient of a typically imaginative Rubin suggestion.42 Vera had refereed an application for the position of Visiting Professor for W ­ omen in Science and Engineering, and she had commended the NSF on its “­grand program.” Her brief as referee had told her that the visiting professor would “also be available to provide advice, counsel, and mentorship for ­women at all levels.” But ­shouldn’t “­women” be replaced by “­people,” she argued? Reflecting on her own experiences, she said why: I have found that male students and male faculty alike have very often never had a professional colleague or teacher who is female. They too need to interact with professional ­women in a professional capacity. Th ­ ese students ­will be the next generation of professional husbands. What their wives are able to accomplish may come in large mea­sure from the willingness of ­these men to accept their wives as professional equals. The counsel which the Visiting Professors offer to male students may be just as valuable as that which they offer to ­women.

The NSF’s Visiting Professor for ­Women in Science and Engineering program was part of the response this impor­tant federal funding agency had made to growing po­liti­cal and social pressure. In 1981, Congress had passed a law requiring the director of the NSF to “transmit to Congress and selected Government officials a biennial statistical report on the participation of ­women and minorities in science and engineering employment and training.” It was a sign of the gradual realization that in­equality between men and w ­ omen was a prob­lem for science itself, not just for the individuals affected. As the director of the NSF, John B. Slaughter, put it in the foreword to the first of the statutory reports to Congress, “The importance of [science and engineering] makes it essential that the best talent be drawn to science and engineering activity from ­every available pool.” 43 Many organ­izations concerned with the advancement of science w ­ ere slow, however, to perceive the issues being raised by w ­ omen in the same way. One of them was the International Astronomical Union (IAU). Even in January 1990, General Secretary Derek McNally set out explic­itly that the

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“IAU regards itself as a body devoted to the promotion of astronomical science and to this extent has tried not to cross the line into m ­ atters of social concern,” and described the status of ­women in astronomy as an “essentially social prob­lem.”  44 The apparent reluctance of the IAU to abandon its conservative position must have been disappointing for Vera. She had been scientifically active in the IAU over many years, including chairing its Commission on Galaxies between 1982 and 1985. Furthermore, less than two years e­ arlier, she had helped the AAS’s Committee on the Status of ­Women in Astronomy to or­ ga­nize a special session, “­Women Worldwide in Astronomy,” during the IAU’s 1988 General Assembly in Baltimore. The proposal, initiated by that committee’s chair, Deidre Hunter, had gone before the IAU’s full executive committee, which had de­cided it could go ahead one eve­ning provided “that ­there be no interference between this ‘specialized’ session and any of the scientific meetings.” 45 The formal report from the session was not included in the IAU’s official publications, but Vera and Deidre Hunter coauthored an account of it in Mercury, the magazine of the Astronomical Society of the Pacific.46 ­Women worldwide, the report documented, faced many common prob­lems, such as: discrimination that may not be as overt as it was in the past, but it still exists in more subtle forms; • ­women generally having to tolerate an atmosphere in which they are not taken seriously, not given responsibility, and not recognized for their contributions as readily as their male colleagues; and • the prejudices of society being perpetuated through the educational system and peer pressure.47 •

The session was well attended, and the organizers w ­ ere satisfied that it had been successful—so much so that they de­cided to ask ­whether a similar event could be held at the next IAU General Assembly, in Buenos Aires. General Secretary McNally, despite his misgivings, had given them hope. “Now that a pre­ce­dent has been set t­ here is no doubt that the IAU is likely to take a sympathetic attitude to impor­tant fringe meetings,” he had said, though tempering it with a reminder that it is the General Secretary’s prerogative to decide what meetings take place at the IAU General Assembly and at what time. Vera joined Margaret Burbidge, who had chaired the Baltimore meeting, and Deidre Hunter in putting forward the proposal. Pointedly, they

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challenged the IAU’s position: “We believe that mea­sures which ­will increase the numbers of ­women in astronomy and increase their participation in astronomical activities worldwide are legitimate areas of concern for the IAU.” The message was getting through, it seems. By the time McNally responded in October 1990, the tone had changed and the response was warm. “­There ­will be no prob­lem in finding a room for your meeting,” he informed Deidre Hunter, and he wished her a very successful meeting. It is pos­si­ble, even, that an incident in July of that year at an IAU symposium in Sydney, Australia, had demonstrated precisely why the IAU should be concerned. A formal reception had been arranged for participants—or rather, for male participants and their female partners—to which none of the handful of female scientists taking part in the meeting had been invited. The sole w ­ oman speaker at the symposium began her late after­noon talk by commenting that she would hurry so that the men in the audience w ­ ouldn’t be late for the reception to which she had not been invited. Anne Cowley, one of the two ­women attending from the United States, told Vera she felt so uncomfortable with the atmosphere at the meeting that she left early, although she had been enthusiastically looking forward to it.48 The US National Committee for the IAU and the AAS did ultimately raise with the IAU concerns about the treatment of ­women astronomers at the meetings it sponsored. In due course, the US committee chair, Kenneth Kellerman, was able to say to the AAS: I am pleased that both the IAU and ICSU [the International Council of Scientific Unions] has acted promptly and firmly in addressing the concerns raised. . . . ​One remaining issue concerns the discussion to hold a meeting on the role of ­women in astronomy. In the past, the IAU has not supported such a meeting on the grounds that the issues w ­ ere po­liti­cal, not scientific. . . . ​ One of the historical strengths of the international scientific ­unions has been their non-­political nature . . . ​thus . . . ​ICSU has been able to speak with a power­ful voice to protect the rights of individual scientists from government-­ imposed restrictions. On the other hand a good case can be made that ­there are legitimate issues to be discussed which affect the ability of ­women scientists everywhere to effectively carry out their research and teaching in astronomy. The format of the next IAU General Assembly ­will be more flexible than it has been in past years and I am sure that the IAU Executive Committee ­will give serious consideration to a well thought out proposal to hold a meeting on the role of ­women in astronomy.49

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Fig. 11.2 A photographic portrait of Vera Rubin in 1993 by Philip Bermingham. (DTM, Car­n e­gie Institution of Washington)

Separately, another impor­tant conference on W ­ omen in Astronomy was convened at the Space Telescope Science Institute in 1992, with the enthusiastic support of two men: the director, Riccardo Giacconi, and the head of AURA, Goetz Oertel. Vera was among the 220 participants, most of whom put their signatures to a call to action—­which the organizers, led by Meg Urry, called “The Baltimore Charter.” It was endorsed by the AAS, NASA, NSF, and AURA and hundreds of posters ­were distributed to observatories and universities.50 Meanwhile, Vera was ramping up one of her most ardent campaigns: to make w ­ omen in science vis­i­ble and influential at the highest levels. To this end, she embarked on a relentless drive to achieve female repre­sen­ta­tion and recognition wherever scientists w ­ ere honored or invited to speak, and whenever decision-­making groups w ­ ere assembled—­boards, panels, organ­izing committees. As one of a tiny minority of female members of the National Acad­emy of Sciences (NAS), she focused on this most prestigious of scientific organ­ization in the United States, and on its operating arm, the National Research Council (NRC).51 In November 1989, newly appointed to the NRC’s board on physics and astronomy and the only w ­ oman member of it, Vera sent the board’s chair,

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astronomer Frank Drake, the latest in a series of letters in the same vein since her election to the NAS: “I note with disbelief the composition of all the other boards whose membership lists have been sent to me.” Reviewing ­those seventeen committees, she had discovered that at least 233 of the 256 ­people chosen ­were men. Then with logical precision, she articulated why the imbalance mattered and what it said about the NAS.52 “­Because membership on NRC committees is often a prerequisite to enhanced stature in the scientific world and to NAS membership, most w ­ omen scientists are thus denied this route,” Vera argued. She enclosed an article quoting figures to support her assertion that all-­male committees perpetuated low participation by ­women.53 She pointed out the consequences of the NAS’s failure to do anything about it: “The absence of significant numbers of capable w ­ omen on NRC committees . . . ​is construed as a statement about the ­limited concern within the NRC and NAS for professional w ­ omen ­scientists.” She urged the physics and astronomy board to lead a change in be­hav­ior. “I ­will be happy to help in this effort,” she advised Drake, “and ­will come to the meeting prepared with a list of well qualified ­women.” A few days ­later, having been sent a list of proposed reviewers for an impor­ tant NRC committee report, Vera belatedly submitted the names of three ­women, each “an outstanding astronomer with a broad understanding of the science . . . ​well qualified to review the de­cade report.”54 Her intervention did not produce the desired result, however. A year on, she penned her next annual letter of complaint, this time to Frank Press, the president of the NAS—­and this time she enlisted several other ­women members of the NAS to do the same. Among them w ­ ere Maxine Singer, the molecular biologist serving then as president of the Car­ne­gie Institution; mathematician Karen Uhlenbeck; and astronomer Sandra Faber. In her own letter, copied by some of her colleagues, Vera wrote: “Nowhere in the NAS do we detect a serious concern for enlarging the participation of ­women ­scientists. . . . ​We look to you to initiate enthusiastic, positive, immediate action to improve the situation, which presently diminishes both the National Acad­emy of Sciences and the scientific endeavor.”55,56 Press’s replies to Vera and her colleagues w ­ ere heartening. Could change be afoot at last? “Your point is well taken and we have to do better,” he wrote to Vera. “I agree ­wholeheartedly with the thrust of your letter.” Furthermore, he intended to take action. He would circulate Vera’s letter to the vari­ous

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boards and commissions, and to section chairs, and would put the m ­ atter on the agenda for the next se­nior staff meeting.57 Nevertheless, Vera’s long experiences would have told her not to celebrate too soon. Hardly anything changed over the following eigh­teen months or so, and Vera shared her utter exasperation with a fellow NAS member, Mildred Dresselhaus, a professor of engineering who had made the modest suggestion to the NAS that, at e­ very one of its annual meetings, t­ here should be a ­woman giving one of the pre­sen­ta­tions. Vera agreed: It is a fine idea that one of the Monday after­noon pre­sen­ta­tions at the NAS annual meeting be given by a w ­ oman. But of course it is a good idea. Why does it need saying? And why does it need saying each year? ­Will it take one letter each year to get a ­woman on the program? I guess I am in a very blue mood when it comes to w ­ omen scientists and their treatment by the NAS. I am tired of my annual letter to Press and to the Home Secretary. . . . ​But tomorrow I w ­ ill start again and write Press about the NAS colloquium that is almost all male. Did no one happen to notice that? I am now giving up on the NRC committees which came to my attention.58

The following year, a group of NRC staff saw a fresh opportunity in the appointment of a new NAS president, Bruce Alberts, and proposed a comprehensive plan of action to bring about greater involvement of minorities and w ­ omen in all NRC activities.59 Yet, in 1996, when Alberts invited Vera to chair the NAS Committee on ­Women in Science and Engineering, she declined. Her email to him reflected a certain weariness with the glacial rate of change and, and as she explained to him, she had to be selective over the commitments she took on. It was a job someone e­ lse could do. Just a few days before her sixty-­eighth birthday she wrote: While I appreciate the kind words, I am failing in my efforts to do my science. And that of course is what must come first. . . . ​I have a suggestion, which is prob­ably unworkable. And that is to get a MAN for the task. As long as the prob­lems of “­Women in . . .” are ­women’s prob­lems, I doubt that they ­will improve. It has to be every­one’s prob­lem. But on ­every committee on which I serve, it is only the w ­ oman who brings up the ­women’s prob­lems. So if you can turn it into a NAS prob­lem, which it surely is, headed by a man who ­really cares, some pro­gress might be made. Good luck.

Nothing would stop Vera, however, from being a gadfly on the back of the NAS. On the verge of the new millennium, she wrote to Bruce Alberts:

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Fig. 11.3 Vera Rubin at Vassar College in 2005, standing in front of a bust of Maria Mitchell. (DTM, Car­n e­g ie Institution of Washington)

WOW!!! What a rec­ord to carry into the year 2000!!! ­You’ve outdone yourselves. Last year I complained about one meeting that had only one ­woman speaker. This year ­you’ve proved that you can do worse. At least next year it should be hard to do worse than this. 21 speakers—­a ll male.60

In 2007, when Vera was nearly eighty years old, the National Academies fi­nally addressed the issue full-on with a 346-­page report from the Committee on Maximizing the Potential of ­Women in Academic Science and Engineering. It was a full and forthright statement, published in the name of the most prestigious organ­izations in the field of academic science, medicine, and engineering. Vera must have felt that its appearance represented significant pro­gress. And yet, the conclusions remained depressingly familiar: “Policy changes are sustainable only if they created a ‘new normal,’ a new way of ­doing ­things. . . . ​The current situation is untenable and unacceptable.” 61 But change t­here has been—at least in some ­things. In the 2019 elections to the National Acad­emy of Sciences, forty p ­ ercent of the new members and foreign associates ­were female—an all-­time rec­ord. Not quite gender parity, but not far off. In 1996, the Association for W ­ omen in Science honored Vera, who had been a member for many years, as the first recipient of a fellowship in rec-

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ognition of her “distinguished efforts” over some twenty-­five years.62 When most w ­ omen wanting to work in science had felt they had l­ittle option but to accept the discriminatory situation as it was, Vera had seen t­ hings differently. She had envisioned a f­ uture in which female scientists would be able to fulfill their potential on an equal footing with men. She had applied her considerable powers of creative thinking and logical argument. She had been per­sis­tent and held to a clear sense of purpose. She had been angry but rarely lost her temper. Her ironic sense of humor, ability to communicate, and sheer charisma had made ­people listen, and won her both admiration and re­spect. As well as lobbying organ­izations, she mentored, advised, and supported countless individual ­women, sometimes at a cost to herself. In 1992, she described to an interviewer what it was like to be a visiting lecturer in a university department when she was the only professional ­woman the female students had ever met. The emotional drain could be almost more than she could bear, she said, b­ ecause the ­women had no one ­else to talk to.63 The gratitude of ­those ­women on whose behalf Vera campaigned, t­ hose for whom she was role model, and ­those she supported personally, is beautifully summed up in a moving personal letter written to Vera in 1986 by the astronomer Wendy Freedman, who went on to be the director of the Car­ ne­gie Observatories between 2003 and 2014. “Thanks for speaking out. I often get the feeling that if ­t hings are any easier for ­women like me, it’s ­because w ­ omen like you have taken the time and energy to help make it so.” 64

CHAPTER 12

WONDERFUL LIFE

V

era’s c­ areer in research was, in her own words, “unconventional.” She liked to be fully in control, deciding for herself what she should do and, with the exception of her remarkable professional partnership with instrumentalist Kent Ford, not dependent on anyone ­else. She did not isolate herself, however—­far from it. Dating back to her days at Georgetown, she was ­adept at networking both in person, at the many meetings she attended and by letter. Her correspondence files, now conserved in the Library of Congress, are full of countless letters to and from other astronomers on subjects such as exchanging copies of papers and discussing observations. Vera’s letters are carefully composed and beautifully written. Professional relationships in some cases became warm and enduring friendships—­for example, with Jan Oort and his wife, Mieke.1 Vera was both sociable and hospitable. Gatherings of friends and colleagues w ­ ere not infrequent throughout Vera’s working life She took hosting visitors and preparing meals in stride, clearing her legendary dining t­ able of working papers when com­pany was expected. Vera’s DTM colleague Alycia Weinberger remembered “lovely dinners at Vera and Bob’s ­house for visiting astronomers or distinguished guests. . . . ​She had a small kitchen, yet she was routinely game to host a dozen ­people for dinner.”2 British astronomer Jocelyn Bell Burnell stayed with Vera and Bob for a week in May 2000 when she was Tuve Visiting Fellow at DTM. They had meals out on the deck overlooking the Rubins’ garden and it was “lovely and very in­ter­est­ing,” she recalled.3 Yet, when it came to her research, Vera was at heart a loner. In 1992, shortly ­a fter Kent Ford had retired, she told interviewer Carol Mockros that she worked in a very personal way, making all the decisions herself, ­doing all the observing herself, and reducing all the data herself. Although she would sometimes observe with young postdoctoral researchers, and she wrote papers jointly with colleagues, such as Norbert Thonnard, she did not plan and

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conduct her observation programs with a team, nor did she have her own gradu­ate students.4 Vera was acutely aware that the liberal ethos at DTM accommodated her individual style and allowed her the freedom in which she could thrive perfectly. She never contemplated moving elsewhere. ­A fter spending the first three months of 1981 at the University of California at Berkeley, where she had held a Chancellor’s Distinguished Professorship, she put her feelings into a very personal letter to director Merle Tuve: “I have just returned to DTM ­after three months visiting the astronomy department at Berkeley, and have fallen in love with DTM all over again. ­A fter the frenetic pace in a large department, I find each day a joy. To be able to sit and do science, to be able to think, and to do it in such a pleasant environment, is remarkable. And so this note is to thank you for making it pos­si­ble for me to do ­these ­things.”5 Despite her g­ reat contentment with working on her research in the tranquility of DTM—­and the desperate challenges of carving out time for her frequent observing trips—­Vera was also generous in sparing time for ­others. She was drawn to serve the wider astronomical and scientific communities by a keen sense of responsibility and desire to improve t­ hings for ­others wherever she could. In par­tic­u­lar, she wanted ­others to know that she was “available at any hour of the day or night for any ­woman astronomer.” 6 She made a point of engaging with the postdoctoral researchers and students who passed through DTM, listening to their talks, and offering supportive feedback and encouragement.7 And yet she was always conscious of her conflicting desires to serve the community and help o­ thers, and to have time to herself to “do astronomy.” “As you must know better than I, it is a continual strug­gle to make time to do science,” lamented Vera in a 1984 letter to Margaret Burbidge. “Both the IAU and the National Acad­emy claim a fair share of my time and I despair on t­ hose days when I am kept busy with such ­matters, even though I recognize their necessity.”8 Nevertheless, she added the news that she had just accepted an invitation to chair the Space Telescope Working Group on Galaxies and Clusters of Galaxies. In her 2011 memoir, Vera included without comment a snapshot of a year in her life around that time, in the form of a calendar for 1985. Despite spending over fifty days at meetings and on visits, and traveling to Germany, Japan, and India, she still found thirty-­four days to go on observing trips to Lowell, Kitt Peak, Palomar, and Las Campanas (Chile).9

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Although she bemoaned having too ­little time for her own science, Vera regularly allowed herself to be distracted from her research by spending time as an academic visitor in vari­ous colleges and universities for periods ranging from a few days to a few months. It is clear she found it stimulating to be around students and a dif­fer­ent group of colleagues, as long it was not for a protracted period. For instance, she accepted Vassar College’s invitation to be its President’s Distinguished Visitor in 1987 “with ­great enthusiasm as well as a sense of excitement and joy,” adding that “To be involved with the students and faculty for a week seems like a g­ reat adventure and a g­ reat gift.”10 Afterward, she wrote to Vassar’s president, Frances D. Fergusson, “I enjoyed ­every minute of it, especially the time with the students. . . . ​I have been thinking about how non-­science students could be introduced to some of the fundamental ideas in science. . . . ​I c­ an’t imagine living in the universe and not knowing a minimum about it.”11 Fergusson, in turn, sent her a heartfelt letter of appreciation: “What an extraordinary week you gave us! With unflagging energy, you shared your intelligence, experience, and good w ­ ill. Students and faculty ­were elated by your appearances in classes and your informal visits with them. You ­were particularly inspirational to students, who felt very comfortable with you b­ ecause of the personal warmth you showed them. Effectively communicating your research to general audiences, you proved yourself an excellent teacher.”12 Such praise for Vera was not unusual. Her personal qualities ­were greatly admired and appreciated wherever she went. Vera was also frequently tempted away from DTM by the prospect of visiting somewhere in the world totally dif­fer­ent and new to her. In 1978, she made her first visit to Japan. ­Because Bob would be attending a week-­long meeting of the Biophysical Society in Kyoto in September, Vera set about organ­izing a simultaneous visit to the Department of Astrophysics at the University of Kyoto, where she gave a lecture on her recent work and had discussions with students and researchers.13 With help from her hosts, Vera and Bob tacked on some days of sightseeing and, of course, hiking. They visited the Tokyo Astronomical Observatory and its Kiso Observatory at Mount Ontake, climbed Mount Hishihodaka, and walked the Azusa River valley.14 Another significant trip overseas for Vera was her visit to Israel in 1984. Over a de­cade e­ arlier, she had somewhat reluctantly turned down an invitation to spend the academic year 1971–1972 as a visiting professor at the Uni-

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versity of Tel Aviv. Back then, with all of her ­children still in school, it had simply been too complicated and too expensive to or­ga­nize.15 So she was delighted when the invitation came to serve on the organ­izing committee for a meeting on galaxies being held at the Weizmann Institute in 1984, and then to remain ­there as a visitor for a month. Vacations did feature in the Rubin ­family travels, too, almost invariably connected to one of the scientific meetings or academic visits that was taking Vera or Bob somewhere in the world. Given their love of camping and hiking, what they did in the summer of 1974 was typical. Vera and Bob traveled to Erice, Sicily, to attend a NATO Advanced Study Institute on the Structure and Evolution of Galaxies, and took Allan with them. When the meeting was finished, all three climbed Mount Etna. ­A fter Sicily, they traveled to Asiago Observatory, near Padua, to visit Sandro D’Odorico, a former postdoctoral fellow at DTM who had worked with Vera. H ­ ere, close to the mountains of northern Italy, ­there w ­ ere more opportunities for hiking.16 When the c­ hildren w ­ ere older and had all left home, Vera and Bob bought a holiday retreat set on the Snake River in Jackson Hole, Wyoming, surrounded by nature and beautiful, unspoiled scenery. They would often spend time t­ here around the New Year. Vera wrote of ­these breaks from her busy schedule: “­There is comfort, even inspiration, in t­ hese brief connections with Nature, that a professional city life permits only intermittently.”17 In Washington, Vera’s outlet for her love of nature was gardening, and a passionate concern for the trees on DTM’s extensive grounds. Gardening was what she did to relax, she said.18 But her views on the DTM trees could, on occasion, stir up fervor in her that must have been far from relaxing. Alycia Weinberger relates how Vera, as an active member of DTM’s “tree committee,” once so annoyed the director about tree issues that he was driven to warn her, “Trees are not worth getting fired over.”19 But perhaps most memorable for Vera of all her travels was the visit she made to the South Pole in December 1997, when she was serving as a member of the National Science Board. She even penned a rhyme, a parody of the popu­lar song “South of the Border, Down Mexico Way.” It went like this: South of the border Down Antarctica Way That’s where we left our hearts Where ­people work and penguins play.

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And now as we wander Our thoughts ever stray South of the border Down Antarctica way.

Jotted on a small sheet of notepaper on her journey home, the wistful words remained in her file with her itinerary and the notes and sketches she made describing her flight from Christchurch, New Zealand, to the US McMurdo Station.20 Bob flew with her to Christchurch, where they had a ­couple of days of mostly ­free time before Vera left on her seven-­and-­a-­half-­hour flight with some thirty or so other passengers. They ­were squashed in like sardines, with a large amount of kit. The aircraft was a Lockheed LC-130 operated by the US Navy and fitted out in military fashion. It was so noisy that earplugs ­were essential. The excitement, however, compensated for the discomfort. Vera, with the other three members of the party representing the National Science Board, spent four nights in a hut on the ice at McMurdo. Their outing to Amundsen-­Scott South Pole Station was a day trip: a three-­hour flight in each direction. Vera was asked ­whether she would like to spend all of her visit to the South Pole station with the astronomers. Would that mean she would miss every­thing e­ lse, she queried with a l­ittle embarrassment—­the penguins, the mountains, and so on? If so, she had no difficulty in voting for the penguins.21 The next day was another exhausting but thrilling outing, this time by he­li­cop­ter to the McMurdo Dry Valleys. Th ­ ese unique landforms, f­ ree of snow and ice, are among the most extreme deserts in the world. ­A fter a third day given over to briefings and inspecting facilities at McMurdo Station, it was another long flight back to Christchurch, where Bob was among the families waiting to greet the exhausted del­e­ga­tion. Before g­ oing home, as was typical for Vera and Bob, they relaxed by spending a few days hiking and traveling around. By the time Vera was appointed by President Bill Clinton to the National Science Board in 1997, and made her trip to Antarctica, she had already become the recipient of a string of honors and awards recognizing both her scientific achievements and her public ser­vice. The scientific significance of her work had ­really begun to attract widespread attention when she, Kent Ford, and Norbert Thonnard published their 1978 paper on the rotation curves of ten spiral galaxies, illustrating beautifully that the “curves” ­were

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stubbornly flat at large distances from the galactic centers.22 Two years l­ ater, in 1980, the trio had extended their database with twenty-­one more spiral galaxies and found similar results.23 Another year on, in 1981, Vera was elected to the National Acad­emy of Sciences, one of the highest honors to which a scientist in the USA can aspire. She was only the second w ­ oman astronomer to be elected, a­ fter Margaret Burbidge in 1978. Election to Fellowship of the American Acad­emy of Arts and Sciences, another significant honor, followed the next year. This was recognition at a high level. Vera had truly joined the scientific elite of the United States. Throughout the 1980s, the number of known spiral galaxies exhibiting the now characteristic flat rotation curves r­ ose. Rubin and Ford had made the optical observations to plot a total of fifty-­four.24 Dark ­matter was being discussed by astronomers everywhere and had also fired the public’s imagination. Vera published extensively and spoke regularly at conferences, and Harvard University bestowed an honorary doctorate on her in 1988. Yale University followed suit in 1990. An even more prestigious honor, however, was soon to come her way. On July 13, 1993, she received a telephone call from Jack Gibbons, assistant to President Clinton for science and technology. It was to tell Vera that she was to be awarded the National Medal of Science, the nation’s highest scientific honor. ­There was to be an award ceremony at the White House at the end of September.25 Vera was aware that the Association for ­Women in Science had nominated her, ­because in 1991 they had asked her to provide a CV.26 She would also have been aware that many names are put forward each year—­there w ­ ere some 150 nominations in 1993. The rules state that no more than twenty medals can be awarded in any calendar year but, on average, far fewer are bestowed. At that point, thirty years ­after the medal’s inception in 1962, a total of only 312 had been presented.27 The award ceremony was a two-­day event, also including a Congressional lunch, a VIP reception, a black-­tie dinner, and a press conference. The pre­ sen­ta­tion of the medals would take place in the Rose Garden at the White House. Guests ­were welcome at some of the events and, in addition to Bob, Vera invited her c­ hildren Allan, Karl, and Judy; her long-­standing colleague Martin McCarthy; her s­ ister, Ruth; and her ­house­keeper, Lucy Herring. Vera’s archived files include vari­ous drafts, some with annotations by Vera, of the citation, the NSF press notice, and the text for a poster board to be

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Fig. 12.1 Vera Rubin with her h ­ ouse­keeper, Lucille Herring, and s ­ ister, Ruth, before the National Medal of Science award ceremony in 1993. (DTM, Car­n e­gie Institution of Washington / The White House)

displayed at the dinner.28 The final version of the citation read: “For her pioneering research programs in observational cosmology which demonstrated that much of the ­matter in the universe is dark and for significant contributions to the realization that the universe is more complex and more mysterious than had been i­ magined.” On a document headed “draft press notice” she circled in red pen an offending phrase: “This result became the acknowledged ‘discovery’ of dark ­matter.” Her suggested substitute toned it down: “­These observations provided convincing evidence of the existence of dark ­matter.” And yet the copy of the final release in the file shows that her edit was not incorporated.

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Fig. 12.2 Vera Rubin with her husband, Bob, and their sons Karl (left) and Allan (second from right). (DTM, Car­n e­gie Institution of Washington)

Asked for four “impact statements” for the poster board, Vera offered suggestions, again in red and among them a question: “In what year w ­ ill six ­women and two men get the National Medal of Science?” It was a reference to the fact that, in 1993, she was one of two ­women alongside six men. However much she might have liked to include it, it’s doubtful that the comment made it onto the final poster. The official description of the medal says it “depicts man, surrounded by earth, sea, and sky, contemplating and seeking to understand nature.” And it is most certainly a male figure. ­There is no rec­ord of what Vera may have thought about that. Something that did make it into the press notice was that all four of Vera and Bob’s ­children had earned doctorates and become “professional scientists,” achievements of which Vera was im­mensely proud. For the poster, Vera changed the text to be more precise than “professional scientists” and used her red pen to substitute “two geophysicists, one astronomer and one mathematician.” The award of the National Medal of Science was the high point of a bumper year for awards. Vera received her fourth honorary doctorate—­from

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Fig. 12.3 President Bill Clinton presenting the National Medal of Science to Vera Rubin in 1993. (DTM, Car­n e­gie Institution of Washington / The White House)

Williams College—in 1993, as well as the Antoinette de Vaucouleurs Lecture and Medal from the University of Texas, and named lectureships at Columbia University and the University of Durham. National and international honors and awards continued to be showered on her in subsequent years. (For a full list, see Appendix 1.) The Royal Astronomical Society had not awarded its highest honor, the Gold Medal, to a w ­ oman since 1828, when it went to Caroline Herschel. It was Vera who, in 1996, fi­nally inspired the society to end this 168-­year, all-­ male stretch. She was greatly touched by the idea of being Herschel’s successor in this astronomical achievement of the highest order. She wrote to the president of the Royal Astronomical Society, Carole Jordan—­who herself had broken new ground by becoming the first female holder of her office—­that “of the many honors I have received this one seems very special.” She was both “amazed” and “delighted.”29 The medal was presented to her at a meeting in London on November 8, 1996, where she gave a talk

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entitled “One Hundred Years of Galaxy Spectroscopy.” Another medal and invitation to give a lecture in that year came from the Weizmann Institute, who named her as the second recipient of its ­Women in Science award. At this time, Vera’s links with the White House ­were flourishing, too. President Clinton had appointed her to his Committee on the National Medal of Science in 1995, and in July 1996 he nominated her to serve on the influential National Science Board (NSB). This advisory body of the National Science Foundation had twenty-­four members (subsequently increased to twenty-­five), each appointed by the president for six years, subject to the approval of the US Senate. Its job is to recommend overall national policies for promoting basic research and education.30 The law requires that nominees ­shall be eminent in the fields of the basic, medical, or social sciences, engineering, agriculture, education, research management, or public affairs; ­shall be selected solely on the basis of established rec­ords of distinguished ser­vice; and ­shall be so selected as to provide repre­sen­ta­tion of the views of scientific and engineering leaders in all areas of the nation.31 While awaiting confirmation by the Senate, which happened in 1997, Vera was sworn in as a con­sul­tant, allowing her to participate as a non-­voting member.32 Asked by the NSB on which committees she would like to serve, Vera chose the Committee on Programs and Plans, citing her knowledge of astronomical facilities funded by the National Science Foundation. And predictably, she told them, “I also have a longstanding, serious interest in Education and ­Human Resources, especially relating to w ­ omen in science.”33 Vera enjoyed this impor­tant work, which resulted in her testifying before a congressional committee on the NSF’s bud­get request, and before the Presidential Commission on the History of ­Women.34 An unexpected outcome of her appointment to the NSB was a series of requests from the First Lady, Hillary Clinton, to meet with her informally when she was preparing for events that involved science. Social invitations from the Clintons followed, too, including one to a surprise birthday party for Hillary. But, as Vera put it, regrettably from her point of view, the “fun” ended with the change of president in 2001.35 The year 1996 also brought an appointment to the Pontifical Acad­emy of Sciences. This illustrious establishment, created in its modern form in 1936 by Pope Pius XI, is based in Vatican City. The l­imited membership consists of eighty men and ­women, of any religion or none, who are among the world’s most eminent scientists. Vera, although raised in the Jewish faith, was not

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very religious and tended to avoid discussions of the subject. On a rare occasion when she was pressed, and her answers recorded, she revealed that she saw no conflict between science and religion. “I know what science is and what I do with science and I accept religion as a concept in my life,” she told her interviewer. Being Jewish was part of Vera’s identity, and the basis of her moral code, but she was clear that science was more impor­tant to her. “Religion is not the most impor­tant t­ hing. It’s what you do and how you do it,” was how she summed up her philosophy.36 Vera went to the plenary meeting of the Pontifical Acad­emy in the ­October a­ fter her election and attended several o­ thers in the following years, including the Jubilee plenary meeting in 2000. The proposed title and agenda of the Jubilee meeting caused Vera considerable discomfort. She wrote on the bottom of the ac­cep­tance form, “Even though the meeting is named ‘Science for Man and Man for Science’ I hope you ­will include some ­women speakers. All of the listed speakers are men. Thank you. Vera Rubin.” Then she thought better of it. She crossed through what she had written and wrote, “Not Sent.” Instead she opted for a less blunt message: “I hope that some ­women speakers w ­ ill be included in the program. Vera Rubin.” Her original spontaneous reaction, though, reveals her true feeling. “I ­will not attend this meeting,” was her comment on the initial circular. ­W hether it was through Vera’s influence, or for some other reason, we do not know, but by the time the meeting took place its title had become “Science and the F ­ uture of Man37 kind.” Her last attendance at a plenary meeting of the Pontifical Acad­emy was in 2008, when she was eighty years old.38 Pontifical Academicians are not required to have had any prior association with the Vatican or the Catholic Church, but Vera had in fact kept up her friendship and professional links with the Jesuit astronomers of the Vatican Observatory since her Georgetown days. Although frustration with the astronomy department at Georgetown was a major reason why she moved to DTM in 1965, Vera l­ater looked back nostalgically on her time t­ here and was gracious in acknowledging the debt she felt she owed to the director, ­Father Francis Heyden, SJ. In 1982, she and Bob made a donation to Georgetown University. In the accompanying letter to the president, F ­ ather Timothy S. Healey, SJ, Vera affirmed, “I have continually realized how impor­tant ­were the opportunities which Georgetown offered, and made pos­si­ble for me.” She explained that she was making the donation partly “in honor of Dr. Francis J.

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Heyden S. J. Without his support and encouragement, my Georgetown education would not have been pos­si­ble.” It was also partly in memory of ­Vera’s ­mother, Rose, who ­earlier in the year had died in a room at the Georgetown University Hospital overlooking the old observatory building. Vera pays warm tributes to Rose, to her f­ather, and to Bob. “Without the support of this remarkable ­woman and my f­ather I would never have succeeded,” she owns, and declares to ­Father Healey that Bob “has been my staunchest supporter all of ­these years.”39 Fifteen years l­ater, Georgetown University invited her to give the 1997 Commencement Address and awarded her an honorary doctorate. Martin McCarthy remained Vera’s principal contact among the Vatican astronomers, and on occasion he sought her advice and help. In 1983, the Vatican Observatory was considering the suitability of its home, Castel ­Gandolfo, fifteen miles (twenty-­five kilo­meters) southeast of Rome, for a modern astronomical research establishment, and ­whether it needed a fa­ cil­i­ty in the more astronomically favorable climate of Arizona. She was invited to give her advice. Martin McCarthy talked to her and made notes. Drawing on her experience of working at DTM, her opinion was that “If you of the Vatican r­eally wish to retain your identity you should realize that Castel Gandolfo has real advantages.” And yet, “one should not count on staying all the time at one’s home site.” She would not deny that a fa­cil­ i­t y in Arizona would be a boon.40 The Vatican Observatory de­cided not to abandon its historic home in Italy but at the same time to construct a state-­ of-­the-­art telescope at the Mount Graham International Observatory in ­A rizona. Vera was one of the principal speakers at the dedication ceremony in 1993. In 1986, Vera helped Martin McCarthy set up the first Vatican Summer School for students, an event held ­every two or three years to this day. Shortly ­a fter it was over, McCarthy wrote an effusive letter to Vera: “Thank you Thank you Thank you both for your fine and most appreciated work at the Vatican Summer School. It was all I dreamed of and more and you worked hardest of us all.” 41 She had given more than twenty lectures and made herself available for almost round-­the-­clock conferences and tutoring sessions.42 They took the students to visit the Galileo House and the Science Museum in Florence and spent a “glorious, exhausting day in Rome to meet the Pope and see the Vatican museum.” 43 The next year she was co-­organizer of a Vatican Study Week on “Large Scale Motions in the Universe.” 44

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Fig. 12.4 Vera Rubin being made an Honorary Doctor of Science at The Ohio State University in 1998. (DTM, Car­ne­gie Institution of Washington)

By the 1990s, when she was in her sixties, Vera had become a national scientific celebrity. She received so many invitations and requests that she had to be quite selective about which she would and could accept. In 2003, she was asked: “What single discovery, invention or innovation would most improve your life?” Back came her witty reply: “A secret day for me e­ very week, that was not available to ­others.” 45 But her packed schedule was no joke. Fitting into her busy life every­t hing she wanted to do—­a nd many ­things she felt it was her duty to do—­had for most of her ­career been a real prob­lem. She confessed to feeling overwhelmed at times by the phone, fax, email, preprints, reprints, and letters. Her most difficult challenge was finding enough time to do what ultimately gave her most personal satisfaction—­ science, and in par­tic­u­lar, observing.46 And yet she seemed to succeed. She continued to publish papers in The Astrophysical Journal and The Astronomical Journal and to produce galaxy rotation curves. Her last paper in The Astrophysical Journal, published in 2005 when she was seventy-­seven years old, rec­ords in the acknowledgements that she was a visiting astronomer at Kitt Peak National Observatory.47 Vera somehow did make time for the most prestigious offers—­the ones that r­ eally w ­ ere too good to turn down. She collected more honorary doctorates, with the distinction bestowed on her by Prince­ton University in 2005 bringing her lifetime total to eleven, and t­ here w ­ ere awards and named lectureships at the rate of one or two a year. (Appendix 1 includes a list.) In a

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particularly fitting sign of just how much had changed over her lifetime, the Cosmos Club, the target of her furious disapproval over thirty years ­earlier, named her the winner of the Cosmos Club Award in 2008. Retirement was not a prospect Vera could readily face. She was, and would remain, a working astronomer. She told colleagues that, when she was hired in 1965, she informed the director of DTM that she would abide by all the rules except one: she would never retire. By 2002, however, she was ready to compromise. She accepted a change in status to se­nior fellow and ­stopped taking her salary so that a young ­woman, Alycia Weinberger, could be hired as a staff scientist.48 Vera may have been influenced in her decision by the tragic discovery that Bob was suffering from an incurable blood cancer. She wrote in April 2002 to explain to colleagues why she would be unable to prepare for a committee meeting at the National Acad­emy of Sciences the following week. “­A fter several months of complex illnesses, including a hospital stay, Bob was diagnosed on Friday with multiple myeloma. Chemotherapy w ­ ill start tomorrow (­unless we ask for more time to look into valid alternatives).” 49 Bob and Vera would have been aware that, even with treatment, his life expectancy was about six years. A further devastating blow came in 2006 when their ­daughter Judy was also diagnosed with multiple myeloma. Bob died on January 18, 2008 and Judy died on May 23, 2014. Vera continued to go into her office u ­ ntil 2014, when she was eighty-­six. Her memory and intellectual powers, however, had gradually been declining, prob­ably for some five years. As she became increasingly frail, the time came to leave DTM. She had been meticulous about keeping virtually e­ very document that she received or personally created, so the filing cabinets in her office ­housed an astonishingly complete rec­ord of a long life of distinction and achievement. Arrangements ­were made for this remarkable collection of papers to be presented to the Library of Congress. Progressively succumbing to the effects of dementia, Vera spent her final two years in care at Prince­ton, near her youn­gest son, Allan. Th ­ ere she died on December 25, 2016.

In June 2009, Queen’s University in Kingston, Ontario (Canada) played host to a five-­d ay meeting in cele­bration of the ­c areer of Vera Rubin, who had turned eighty years old the previous year. Called “Unveiling the Mass: Extracting and Interpreting Galaxy Masses,” it was attended by many

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Fig. 12.5 Vera Rubin with her d ­ aughter, Judy Young, in 2009 at the meeting in Kingston, Ontario, held to celebrate Vera’s ­c areer. (Peter Teuben)

a­ stronomers who knew Vera and held her in high esteem, as well as by Vera herself and her ­daughter, Judy. Speaking at a banquet in her ­mother’s honor, Judy characterized Vera’s life as “a love story,” highlighting her “love of astronomy, love of learning and curiosity, love of f­ amily and friends.”50 This was not simply a d ­ aughter’s sentimental view. Judy was also a fellow astronomer who had worked with her ­mother as a professional colleague, so she was in some position to be objective. The three driving personal passions Judy identified—­combined with grit, determination, stamina, and a streak of stubbornness—­made Vera the ­great astronomer she was and endeared her to her admirers. Anyone following the story of her life, reading her correspondence, or reviewing the transcripts of interviews she gave could not disagree with Judy. The evidence is all ­there. Judy recollected that Vera would often say what a privilege and gift it was to wake up e­ very day and get paid to do what she loved. Vera’s youn­gest son, Allan, even as a small boy, sensed his ­mother’s delight in her life as an astronomer. At five years old, he asked her w ­ hether she had to pay to be allowed to work at her office.51 Vera herself declared, “Successful nights at a telescope are among the happiest nights of my life.” Beyond being intellectually in­ter­est­ing, she said, “Observing is spectacularly lovely. R ­ eally, r­ eally 52,53 quite inspiring.”

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Fig. 12.6 Vera and Bob Rubin with their c ­ hildren and grandchildren on the occasion of their fiftieth wedding anniversary, in 1998. (DTM, Car­n e­gie Institution of Washington)

Quite plainly, Vera loved astronomy, and her e­ ager curiosity about the universe never left her. “I enjoy analyzing the observations, trying to see what you have, trying to understand what y­ ou’re learning,” she told Sally Stephens of Mercury magazine in 1992. “­There’s also this incredible hope that somehow we can learn how the universe works. What keeps me ­going is this hope and curiosity, this basic curiosity about how the universe works.”54 What she learned is documented in over one hundred papers, published by mainstream research journals, over the course of some fifty productive years. Vera could never put her professional work into a “silo,” separate from her ­family. Both w ­ ere of equal importance—­inseparable facets of what gave Vera’s life its meaning—­and the interplay between them was an extraordinary source of strength for her. In a few lines of advice from her own experience of combining parenthood with her ­career, she told a student, “I have actually found it easier to face the day-­to-­day challenges of being a parent

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Fig. 12.7 Bob and Vera Rubin dancing in the 1980s (date unknown). (DTM, Car­n e­g ie Institution of Washington)

when I also face the day-­to-­day prob­lems of understanding the universe.”55 She could equally well have reversed the order. The emotional support and sheer physical help of her ­family, and of Bob in par­tic­u­lar, w ­ ere sustaining f­ actors throughout her life, but it was not all one-­way. Vera and Bob cared greatly for their parents, c­ hildren, and grandchildren. Vera’s s­ ister, Ruth, spoke of her “being t­ here when needed.” Vera and Ruth w ­ ere close. Although both w ­ ere busy professional w ­ omen, they ­were in frequent contact by phone—­a lmost daily in their l­ater years.56 For historian David DeVorkin, the ­great importance of ­family relationships in shaping Vera’s personality came sharply into focus in 2002, when he met Ruth at a reception before Vera gave a talk at the National Air and Space Museum in Washington, DC. He was fascinated to listen to the ­sisters chattering away, and the experience revealed to him that the oral history interviews he had recorded with Vera in 1995 and 1996 “had a long way to go to capture the w ­ hole person.”57 Although Vera as a person and her achievements overall encompass much more than a cata­log of research papers, the way that history judges ­people means that Vera’s scientific legacy ­will inevitably be assessed sepa-

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Fig. 12.8 Vera Rubin reading to her grand­d aughter Laura in 1988. (DTM, Car­n e­gie Institution of Washington)

rately, especially by t­hose who document how the story of dark m ­ atter unfolded through the twentieth c­ entury. She found herself cast in a starring role ­because she was insatiably curious about galaxies and, at a crucial time, embraced a novel tool. The image tube spectrograph gave her the means to explore at the frontiers of knowledge. Collaborating with Kent Ford, who had complementary skills, she devised her own part, which she played with consummate skill. How can her influence on the development of a complicated plot best be described, against the backdrop of what other players ­were d ­ oing? The long answer is the story of Chapter 9, which explores the question in detail. For the short answer, we need look no farther than the tributes and obituaries that followed Vera’s death in such profusion. The headlines ­were split between ones that confidently proclaimed, as in Nature and the Washington Post, that Vera Rubin “confirmed the existence of dark ­matter,” and ­others, as in the Los Angeles Times, that more cautiously said she “found evidence” of dark m ­ atter in the form of dark ­matter halos around galaxies.58 Hers was not the only observational evidence, but for many doubters it became the most convincing.

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Dennis Overbye, writing in the New York Times, quoted Jeremiah ­ striker’s explanation that “Vera’s work . . . ​clinched the case for dark ­matter O for most astronomers,” ­because she looked at familiar galaxies and made optical observations of a kind that are easy to understand, although “it helped that at the same time theoretical physics was exploding with new ideas . . . ​ which implied the existence of new kinds of subatomic particles left over from the Big Bang.”59 The parallel results from radio astronomy w ­ ere influential, too. Sandra Faber, in her tribute for Scientific American, captured more succinctly than anyone why Overbye’s claim that Vera “transformed modern physics and astronomy with her observations,” might be justified. Faber chose her words carefully to be precise and factual. “Rubin’s most impor­tant scientific contribution was establishing that the orbiting speeds of gas clouds in the outer parts of galaxies remain constant to distances well beyond the vis­i­ble starlight.” Then Faber gave three reasons why Vera was so influential: “First was the clarity and directness of the papers, including beautiful illustrations of the raw spectra that she was measuring—­the flatness of the rotation curves could not be denied. Second was the fact that Rubin and her colleagues followed up with several more papers over the next few years, each one enlarging the sample and demonstrating the ubiquity of flat [rotation] curves. Third ­were Rubin’s pre­sen­ta­tions at numerous astronomical conferences, which, like the published papers, ­were clear, direct, pared down to essentials, and ultimately compelling.” 60 Vera did not credit herself with having especially deep intuition about the universe. Rather, she knew she had the skills and motivation to make detailed and credible observations. And she was determined that the observational data she published would be reliable. “If someone had to re-­observe what I had done within five or ten years I would feel very much like I’d failed,” she told Carol Mockros in 1992.61 For several years before her death, Vera Rubin was strongly tipped as a potential winner of the Nobel Prize in Physics, still regarded as the world’s most prestigious accolade in the subject. When no prize materialized for Vera before she died, “many attributed the oversight to gender bias,” as the Washington Post put it. Harvard physics professor Lisa Randall was one of ­those who argued strongly that Vera should have had at least a share in the physics prize.62 ­Until the Nobel Foundation discloses the contents of its archive fifty years hence, we s­ hall not know w ­ hether she was nominated or discussed as a potential recipient. The dearth of awards to ­women is an undeniable fact,

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and the choices of Nobel laureates are not infrequently controversial: ­there are many deserving individuals, and few Nobel Prizes. Se­lection is especially tough for the astronomers who are in competition with an enormous community of physicists. ­There would have been a certain irony had Vera been awarded the prize in physics since she rejected the notion that she might be described even as an astrophysicist, putting on rec­ord in 2007: “All my life I’ve been introduced to p ­ eople as an astrophysicist, and I say ‘No, I’m an astronomer.’ I d ­ on’t need the physics halo.” 63 Vera herself once claimed that she neither knew nor cared what role history would assign to her.64 The American Physical Society led the way in 2013, however, by placing DTM on its Register of Historic Physics Sites, “In recognition of the pioneering research of Vera C. Rubin and W. Kent Ford Jr. whose mea­sure­ment of galactic rotation curves provided evidence for the existence of dark ­matter.” 65 Vera was clearly delighted when such honors came her way, but she often repeated that the daily satisfaction and joy she got from d ­ oing what she loved was the best reward. If other astronomers found her observations “irresistible,” it was the highest compliment she could wish for. And they certainly did.

APPENDIX

VER A COOPER RU B IN

July 23, 1928–­December 25, 2016 NOTAB LE HO N ORS AN D APP OINTME NTS

This list is based primarily on information contained in an unpublished CV compiled by Vera Rubin in 2009 and held by the Car­ne­gie Institution for Science’s Earth and Planets Laboratory (formerly the Department of Terrestrial Magnetism). HO NOR ARY DEGREE S

1978 1988 1990 1993 1996 1997 1998 2001 2002 2003 2005

Creighton University Harvard University Yale University Williams College University of Michigan Georgetown University The Ohio State University Smith College Grinnell College Ohio Wesleyan University Prince­ton University

OTHER ACADEM IC HON ORS

1981 1982 1996

Elected to National Acad­emy of Sciences Elected to Fellowship of the American Acad­emy of Arts and Sciences Elected to Pontifical Acad­emy of Sciences

254 A pp e n d i x VISITIN G ACADEM IC APP OINTME NTS

1981

University of California, Berkeley, Chancellor’s Distinguished Professor 1982–1983 Phi Beta Kappa Visiting Scholar 1987 Vassar College, President’s Distinguished Visitor 1988 University of Texas, Austin, Beatrice Tinsley Visiting Professor 1989 Haverford College, Philips Visitor 1993 Williams College, Bernhard Visiting Fellow 1995 University of Leiden, The Netherlands, Oort Visiting Professor 1999 Northwestern University, Kreeger-­Wolf Professor MEDAL S AN D OTHER AWARDS

1993 1994 1996 1996 2001 2002 2003 2004 2006 2007 2008 2009

United States National Medal of Science Dickson Prize for Science, Car­ne­gie Mellon University Weizmann ­Women and Science Award Gold Medal of the Royal Astronomical Society (UK) John Scott Award, City of Philadelphia Gruber Foundation International Cosmology Prize Catherine Wolfe Bruce Medal of the Astronomical Society of the Pacific James Craig Watson Medal, National Acad­emy of Sciences Alumnae and Alumni of Vassar College Distinguished Achievement Award Richtmeyer Memorial Award, American Association of Physics Teachers Cosmos Club, Washington D. C., Annual Award Adler Planetarium, Lifetime Achievement Award

NAMED LEC TU RE S

1986 1991 1992

National Air and Space Museum, Elliot Montroll Memorial Lecture Oregon State University, Yunker Lecture Wesleyan University, Connecticut, Kenneth Sturm Memorial Lecture

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1993 University of Durham, UK, Grubb Parsons Lecture 1993 Columbia University, Jeffrey Bishop Lecture 1993 University of Texas, Antoinette de Vaucouleurs Lecture and Medal 1994 Pennsylvania State University, Russell Marker Lecture National Radio Astronomy Observatory, Jansky Lecture 1995 American Astronomical Society, Henry Norris Russell Lecture 1997 Drexel University, Kaczmarczik Lecture 1998 University of Oxford, UK, Halley Lecture Washington Philosophical Society, Joseph Henry Lecture 2002 Naval Research Laboratory, Thomas Edison Lecture National Air and Space Museum, Jaylee and Gilbert Mead Lecture 2003 Cornell University, Thomas Gold Lecture 2007 University of Mary­land, Shih-­I Pai Lecture NOTAB LE APP OINTME NTS O N COMM IT TEE S , BOARDS , PAN E L S

1972–1976 US National Committee of the International Astronomical Union (IAU) 1972–1977 Space Astronomy Committee, National Acad­emy of Sciences 1973–1976 Board of Directors of Association of Universities for Research in Astronomy (AURA) 1975–1979 Visiting Committee, National Radio Astronomy Observatory 1976–1979 Users Committee, Kitt Peak and Cerro Tololo Observatories 1976–1984 Visiting Committee, Department of Astronomy, Harvard University 1977–1980 Council of the American Astronomical Society (AAS) 1978–­c. 2010 Lowell Observatory Advisory Board 1979–1985 Vice President, then President of Commission 28 (Galaxies) of the IAU 1979–1985 Editorial Board of Science magazine (again 2001–2009)

256 A pp e n d i x

1980–1983 Visiting Committee, Kitt Peak and Cerro Tololo Observatories 1984–1985 Chair, Space Telescope Working Group on Galaxies and Clusters of Galaxies 1984–1986 Council of American W ­ omen in Science (AWIS), and again in 1993–1995 1987–1993 National Acad­emy of Sciences Committee on ­Human Rights 1990–1992 Visiting Committee, Space Telescope Science Institute 1990–1992 Board on Physics and Astronomy, National Acad­emy of Sciences 1992–1995 Chair, Astronomy Section, National Acad­emy of Sciences 1993–1996 Board of Trustees, Associated Universities Inc. 1995–1997 President’s Committee on the National Medal of Science 1995–1998 Visiting Committee, Department of Astronomy, Harvard University 1997–2003 National Science Board (Presidential appointment) 1997–2002 Visiting Committee, Center for Astrophysics, Harvard University 1999–2001 Advisory Board, Peter Gruber Foundation Cosmology Prize M ISCE LL AN EOUS HON ORS

1997 2017 2017 2017 2018 2019

Asteroid 5726 named Rubin Car­ne­gie Institution for Science established Vera Rubin Postdoctoral Fellowship AAS Division of Dynamical Astronomy established Vera Rubin Early C ­ areer Prize Vera Rubin Ridge in Gale crater on Mars named University of California Santa Cruz established Vera Rubin Presidential Chair for Diversity in Astronomy The LSST proj­ect (formerly the Large Synoptic Survey Telescope, now the Legacy Survey of Space and Time) named the Vera C. Rubin Observatory

Notes

INTRODUCTION

1. “NSF-­Supported Observatory Renamed for Astronomer Vera C. Rubin,” National Science Foundation news release 20-001, January 7, 2020, https://­w ww​.­nsf​.­gov​/­news​/­news​_­summ​.­jsp​?­cntn​_­id​=2­ 99739&org​ =­NSF&from​=n ­ ews. 2. “Vera C. Rubin Observatory Designation Act,” H. R. 3196, 116th Congress (2019–2020), https://­w ww​.­congress​.­gov​/­bill​/­116th​-­congress​/­house​-­bill​/­3196​ /­text. 3. “Vera Rubin Early C ­ areer Prize,” Division on Dynamical Astronomy, American Astronomical Society, https://­dda​.­aas​.­org​/­awards​/­rubin. 4. The acronym LSST has now been redesignated to stand for the Legacy Survey of Space and Time. The 8.4-­meter telescope being used for the survey is known as the Rubin Observatory Simonyi Survey Telescope. “Vera C. Rubin Observatory Proj­ect Mission Statement,” https://­w ww​.­lsst​ .­org​/­about. 5. Car­ne­gie Science, “Vera Rubin Who Confirmed ‘Dark M ­ atter’ Dies,” December 26, 2016, https://­carnegiescience​.­edu​/­news​/­vera​-­rubin​-­who​ -­confirmed​-­“dark​-­matter”​-­dies. 6. Fritz Zwicky, “Die Rotverschiedbung von extragalktischen Nebeln,” Helvetica Physica Acta 6 (1933): 110. 7. Judy Young, after-­dinner address given at “Unveiling the Masses,” meeting in honor of Vera Rubin’s ­career, Queen’s University, Kingston, Ontario, Canada, June 2009. Manuscript courtesy of Rubin ­family. 8. Deidre A. Hunter, “Vera Cooper Rubin (1928–2016),” Publications of the Astronomical Society of the Pacific 129, no. 974 (April 2017): 1–4, 1. 9. “Remembering Vera,” “Memories” section, Earth and Planets Laboratory, Car­ne­gie Science, https://­dtm​.­carnegiescience​.­edu​/­remembering​-­vera. 10. “NSF-­Supported Observatory Renamed.”

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N O T E S T O PA GE S 5 – 1 2

1 . T H E L U R E O F T H E S TA R S

1. Vera Rubin, interview by David DeVorkin, September 21, 1995, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­aip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​/­oral​-­histories​ /­5920​-­1. Much material in this chapter that is not referenced to other sources has made use of information in the online transcript of this interview. 2. “The Jews of Vilna at the Beginning of the 20th ­Century,” Yad Vashem, World Holocaust Remembrance Center, Jerusalem, http://­w ww​.­yadvashem​ .­org​/­y v​/­en​/­exhibitions​/­vilna​/­background​/­20century​.­a sp. 3. Pete Cooper, personal recollections, 1989, unpublished audio recording. Courtesy of the Rubin f­ amily. 4. Pete Cooper, personal recollections. 5. “Jewish Massacre Denounced,” New York Times, April 28, 1903. 6. Eric Schulmiller, “For the Glove of the Game,” Forward, January 4, 2012, http://­forward​.­com​/­articles​/­148971​/­for​-­the​-­glove​-­of​-­the​-­game​/­. 7. Tomas Balkelis, “Opening Gates to the West: Lithuania and Jewish Migrations from the Lithuanian Provinces, 1867–1914,” Ethnicity Studies 1–2 (2010): 41–66. 8. Pete Cooper, personal recollections. 9. Pete Cooper, personal recollections. 10. “SS Kroonland,” Wikipedia, June 1, 2018, https://­en​.­wikipedia​.­org​/­wiki​/­SS​ _­K roonland. 11. “Ellis Island History,” The Statue of Liberty—­Ellis Island Foundation, https://­w ww​.­libertyellisfoundation​.­org​/­ellis​-­island​-­history. 12. Pete Cooper, personal recollections. 13. Pete Cooper, personal recollections. 14. Pete Cooper, personal recollections. 15. Pete Cooper, personal recollections. 16. Pete Cooper, personal recollections. 17. Pete Cooper, personal recollections. 18. Pete Cooper, personal recollections. 19. Pete Cooper, personal recollections. 20. Gene Smiley, “Recent Unemployment Rate Estimates for the 1920s and 1930s,” The Journal of Economic History 2 (1983): 487–493. 21. Vera C. Rubin, “An In­ter­est­ing Voyage,” Annual Review of Astronomy and Astrophysics 49, no. 1 (2011): 1–28, 2. 22. Ruth Cooper Burg, My Book of Ruth, published privately, 2016, 10–11, 16–18. 23. J. P. Webster, “The Story of Byberry 1906–2006, Philadelphia State Hospital,” posted May 2, 2017, accessed June 3, 2018, http://­www​.­philadelphiastatehospital​ .­com​/­index​.­html. 24. Pete Cooper, personal recollections.

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25. Pete Cooper, personal recollections. 26. Pete Cooper, personal recollections. 27. Pete Cooper, personal recollections. 28. Pete Cooper, personal recollections. 29. “D.C. Subway Is Predicted by Van Duzer,” Washington Post, April 8, 1941, 19. 30. Pete Cooper, personal recollections. 31. Pete Cooper, personal recollections. 32. Burg, My Book of Ruth, 36. 33. Pete Cooper, personal recollections. 34. Pete Cooper, personal recollections. 35. Vera Rubin, interview by Alan Lightman, April 3, 1989, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, www​.­aip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​/­oral​-­histories​ /­33963. 36. Rubin, “An In­ter­est­ing Voyage,” 3. 37. Rubin, interview by Lightman. 38. J. G. Porter, “­Triple Conjunctions of the Planets,” Journal of the British Astronomical Association 91, no. 6 (1981): 567–575. 39. G. P. Können and J. Meeus, “­Triple Conjunctions: Twins and Triplets,” Journal of the British Astronomical Association 93, no. 1 (1982): 20–24. 40. J. J. Love and P. Coïsson, “The Geomagnetic Blitz of September 1941,” Eos 97, no. 20 (2016): 18–22. 4 1. James Jeans, The Stars in Their Courses (Cambridge: Cambridge University Press, 1931), ch. 6. 42. Rubin, interview by Lightman. 43. Arthur Eddington, The Expanding Universe (Cambridge: The University Press, 1933), ch. 2, “­Spherical Space.” 4 4. Edwin Hubble, The Realm of the Nebulae (New Haven: Yale University Press, 1936). 45. Rubin, interview by Lightman. 46. “Mission and History,” Franklin Institute web site, https://­w ww​.­fi​.­edu​/­about​ -­us​/­mission​-­history. 47. James Stockley, “The Fels Planetarium of the Franklin Institute,” Scientific Monthly 38 (1934): 194–198. 48. Rubin, “An In­ter­est­ing Voyage,” 3. 49. “Citizens of Northwest Seek $450,000 for New School,” Washington Post, June 12, 1937, 13. 50. “Citizen Groups Protest Plans of New School,” Washington Post, Decem­ ber 22, 1937, 34. 51. “Coo­lidge High Plan Approved by Arts Group: Georgian Type of Building ­Will Be Erected in Takoma Park,” Washington Post, January 15, 1938, X15.

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52. “Debate Raging over Names of Schools-­to-­Be,” Washington Post, Novem­ ber 14, 1937, 16. 53. Rubin, “An In­ter­est­ing Voyage,” 3. 54. Rubin, “An In­ter­est­ing Voyage,” 3. 55. Vera Cooper, 1945 manuscript. Courtesy Allan Rubin. 56. Vera Cooper, “Model Building Is New Hobby of Coo­lidge High School Student,” Ju­nior Star (Washington, DC), January 17, 1943, newspaper cutting, Department of Terrestrial Magnetism Archives, General Files, Series 2: Rubin, Vera C.—­Biographical (3 boxes), Car­ne­gie Institution of Science, Washington, DC. 2 . AN ASPIRING ASTRONOMER

1. Vera Rubin, interview by David DeVorkin, September 21, 1995, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­aip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​ /­oral​-­histories​/­5920 ​-­1. Much material in this chapter that is not referenced to other sources has made use of information in the transcript of this interview. 2. Henry Albers, Maria Mitchell: A Life in Journals and Letters (New York: College Ave­nue Press, 2001), chs. 1, 2. 3. Albers, Maria Mitchell, chs. 7, 8. 4. Renée Bergland, Maria Mitchell and the Sexing of Science (Boston: Beacon Press, 2008), chs. 10, 11. 5. Albers, Maria Mitchell, chs. 8–11. 6. “Maud W. Makemson,” Vassar Encyclopedia, 2008, http://­vcencyclopedia​ .­vassar​.­edu​/­faculty​/­prominent​-­faculty​/­maud​-­w​-­makemson​.­html. 7. Maud Worcester Makemson, “The Orbit of Comet f1927 (Gale) with Special Reference to the Question of Double Solutions,” Lick Observatory Bulletin 15 (1930): 27–34. 8. Lutz D. Schmadel, “(1312) Vassar,” in Dictionary of Minor Planet Names, 5th rev. and enl. ed. (Berlin: Springer, 2003), 107. 9. Henry Noble McCracken, address to New York Vassar Club, January 19, 1946, in “A Documentary Chronicle of Vassar College: 1940–1949,” 2001, https://­chronology​.­vassar​.­edu​/­records​/­1946​/­. 10. “A History of Vassar College,” Vassar Info, http://­info​.­vassar​.­edu​/­about​ /­vassar​/­history​.­html. 11. “Vassar Club Washington DC,” http://­vassarclubdc​.­org​/­about​/­. 12. Vera Rubin, interview with Carl Lankowski and Pam Lankowski, November 5, 2011, Oral Histories, Historic Chevy Chase DC, https://­w ww​ .­historicchevychasedc​.­org​/­oral​-­histories​/­vera​-­rubin​/­.

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13. “Let Us Strive On . . . ,” Vassar Chronicle 3, no. 1, September 1, 1945. Vassar College publications Vassar Chronicle, Miscellany News, and Vassar Quarterly can all be accessed at http://­newspaperarchives​.­vassar​.­edu. 14. Anne MacKay, “Vassar in the 1940s,” Vassar 150, Memories, posted 2011, http://­150​.­vassar​.­edu​/­memories​/­year​-­1948​/­vassar​-­in​-­the​-­1940s​.­html. 15. “A Documentary Chronicle of Vassar College: 1940–1949,” entry dated 1943 February 8, https://­chronology​.­vassar​.­edu​/­records​/­1943​/­. 16. “Cushing House,” Vassar Encyclopedia, posted 2015, http://­vcencyclopedia​ .­vassar​.­edu​/­buildings​-­grounds​/­buildings​/­cushing​-­house​.­html. 17. Molly Geiger Schuchat, “Always Starry-­Eyed,” Vassar Quarterly 93, no. 4, September 1, 1997. 18. Vassar College, Miscellany News 30, no. 3, September 19, 1945. 19. MacKay, “Vassar in the 1940s.” 20. Henry Albers, “A Lofty Gravity,” Vassar Quarterly 83, no. 3, June 1, 1987. 21. Vera Rubin’s application to Cornell University, Vera Rubin file, box 203, Gradu­ate School Student Rec­ords, 1891–2014, Cornell University Rare Books and Manuscript Collections. 22. W. F. Meyer, in “Reviews,” Publications of the Astronomical Society of the Pacific 51, no. 304 (1939): 370–372. 23. “Maud W. Makemson,” Vassar Encyclopedia. 24. Vera Rubin student notebook, box 94, folder 8, Vera C. Rubin Papers, Manuscript Division, Library of Congress (hereafter Vera Rubin Papers). 25. Vera C. Rubin, “An In­ter­est­ing Voyage,” Annual Review of Astronomy and Astrophysics 49, no. 1 (2011): 1–28, 3. 26. Harlow Shapley and Helen E. Howard, A Source Book in Astronomy (New York: McGraw-­Hill, 1929). 27. “Maud W. Makemson,” Vassar Encyclopedia. 28. Vera Rubin, Bright Galaxies, Dark M ­ atters (Woodbury, NY: American Institute of Physics, 1997), 71. 29. O. Howard Winn, “Vassar Changed the Direction of My Life,” Vassar 150, Memories, posted 2011, http://­150​.­vassar​.­edu​/­memories​/­year​-­1950​/­vassar​ -­changed​-­the​-­direction​-­of​-­my​-­life​.­html. 30. John Rodden, “Lewis Feuer, A ­Century Appreciation,” Society 49 (2012): 534–540. 31. Schuchat, “Always Starry-­Eyed.” 32. Mary Landon Sague, “Science at Vassar T ­ oday,” Vassar Quarterly 33, no. 2, December 1, 1947. 33. Henry Norris Russell, Raymond Smith Dugan, and John Quincy Stewart, Astronomy, 3rd ed. (Boston: Ginn and Co., 1945). 34. William M. Smart, Text-­Book on ­Spherical Astronomy 4th ed. (Cambridge: Cambridge University Press, 1944).

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35. “Eastern Colleges Science Conference,” Vassar Chronicle 4, no. 9, November 9, 1956. 36. Yale Scientific Magazine 21, no. 7 (April 1947): 28. 37. Robert Tindol, “Physics World Poll Names Richard Feynman One of 10 Greatest Physicists of All Time,” CalTech News, December 2, 1999, http://­w ww​.­caltech​.­edu​/­news​/­physics​-­world​-­poll​-­names​-­richard​-­feynman​ -­one​-­10​-­greatest​-­physicists​-­a ll​-­time​-­368. 38. “5 Students Attend Science Conference,” Vassar Chronicle 5, no. 26, May 1, 1948. 39. Marvin Caplan, “Trenton Terrace Remembered: Life in a ‘Leftist Nest,’ ” Washington History 6, no. 1 (1994): 46–65. 40. “Honor Student List Presented by Dean,” Vassar Chronicle 5, no. 1, September 20 1947. Inclusion on the “Dean’s List,” or “Honor List,” a practice generally associated with colleges and universities in North Amer­i­ca, recognizes students who have reached a high level of academic achievement in their studies. It does not indicate that the student is enrolled for an honors degree. 4 1. Vera Rubin’s application to Cornell University, Vera Rubin file, box 203, Gradu­ate School Student Rec­ords, 1891–2014, Cornell University Rare Books and Manuscript Collections. 42. Maude Makemson to Vera Rubin, April 18, 1957, box 94, folder 13, Vera Rubin Papers. 43. Vera Rubin’s transcript, held in the Registrar’s Office at Vassar College, is headed in manuscript “Honors ΦΒΚ.” Phi Beta Kappa is a national honor society in the US. Vassar College was granted a charter by Phi Beta Kappa in 1898 allowing its Vassar Chapter to name each spring students in the se­nior class who would be eligible for membership of the society. Se­lection represents recognition of a high level of academic achievement, breadth of study and evidence of intellectual adventurousness. 4 4. Rubin, Bright Galaxies, Dark M ­ atters, 214. 45. Joan Brown, “Se­niors Await Graduation Ceremony,” Vassar Miscellany News 32, no. 25, May 5, 1948. 46. “Mark A. McCloskey Dead at 86,” New York Times, November 15, 1977. 47. Schuchat, “Always Starry-­Eyed.” 3 . CO R N E L L A N D T H E R O TAT I N G U N I V E R S E

1. Vera Rubin, interviews by David DeVorkin, September 21, 1995, and May 9, 1996, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­a ip​.­org​/­history​-­programs​/­niels​ -­bohr​-­library​/­oral​-­histories​/­5920​-­1, https://­w ww​.­a ip​.­org​/­history​-­programs​ /­niels​-­bohr​-­library​/­oral​-­histories​/­5920​-­2. Much material in this chapter, not

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referenced to other sources, has made use of information in the online transcripts of ­these interviews. 2. Robert Rubin, manuscript letter to Pete and Rose Cooper, November 8, 1947. Courtesy Allan Rubin. 3. Henry C. Herge, Navy V-12 (Paducah, KY: Turner Publishing, 1996). 4. Robert Rubin file, box 203, Gradu­ate School Student Rec­ords, 1891–2014, Cornell University Rare Books and Manuscript Collections. 5. Donald H. Menzel to Vera Rubin, January 8, 1948, box 95, folder 8, Vera C. Rubin Papers, Manuscript Division, Library of Congress (hereafter Vera Rubin Papers). 6. Vera Rubin file, box 203, Gradu­ate School Student Rec­ords, 1891–2014, Cornell University Rare Books and Manuscript Collections. 7. Paul L. Hartman, “R. William Shaw, 1904–1995,” Bulletin of the American Astronomical Society 28, no. 4 (1996): 1463–1464. 8. “Portrait Photo­graph of R. William Shaw, Professor of Astronomy,” 1942, Cornell University Faculty Biographical Files, #47-10-3394, Rare Book and Manuscript Collection, Cornell University Library, https://­digital​.­library​ .­cornell​.­edu​/­catalog​/­ss:573773. 9. Vera Rubin file, Cornell University. 10. Philip D. Nicholson, Jennifer Ballard, and Shianne Beer, “History of the Fuertes Observatory,” Cornell Astronomical Society, https://­w ww​ .­cornellastrosociety​.­org​/­f uerteshistory. 11. Paul L. Hartman, The Cornell Physics Department: Recollections and a History of Sorts (Ithaca, NY: Physics Department at Cornell University, 1993) 11, 63, 177, 180. https://­ecommons​.­cornell​.­edu​/­handle​/­1813​/­2093. 12. R. William Shaw and Samuel L. Boothroyd, Manual of Astronomy: A Guide to Observation and Laboratory Interpretation in Elementary Astronomy 3rd ed. (New York: Appleton-­Century Crofts, 1947). 13. R. William Shaw, “Reports of Observatories, 1948–1949,” Astronomical Journal 54 (1949): 205–206. 14. Dirk Brouwer, “Report of the Astronomical Fellowship Committee,” Annual Report of the Maria Mitchell Association 49 (1951): 10–11. 15. Gordon Newkirk, interview by David DeVorkin, June 1, 1983, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD,https://­w ww​.­a ip​.­org ​/­history​-­programs​/­niels​-­bohr​-­library​/­oral​ -­histories​/­27554. 16. Hartman, The Cornell Physics Department, 201–202. 17. R. William Shaw, “Reports of Observatories, 1946–1947,” Astronomical Journal 53 (1948): 241–242. 18. Kristine Larsen, “Reminiscences on the Life of Martha Stahr Carpenter,” Journal of the American Association of Variable Star Observers 40 (2012): 51–64, https://­w ww​.­aavso​.­org​/­media ​/­jaavso​/­2838​.­pdf.

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19. Larsen, “Reminiscences.” 20. Vera Rubin to Lawrence W. Fredrick, December 20, 1974, Department of Terrestrial Magnetism Archives, General Files, Series 2: Rubin, Vera C.—­ Biographical (3 boxes), Car­ne­gie Institution of Science, Washington, DC. 21. Hartman, The Cornell Physics Department, 209–210. 22. Vera Rubin, interview by Alan Lightman, April 3, 1989, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://www​.­a ip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​/­oral​ -­histories​/­33963. 23. J. H. Oort, “Observational Evidence Confirming Lindblad’s Hypothesis of a Rotation of the Galactic System,” Bulletin of the Astronomical Institutes of the Netherlands 3, no. 20 (1927): 275–282. 24. William W. Morgan, Stewart Sharpless, and Donald Osterbrock, abstract of paper presented at the meeting of the American Astronomical Society in December 1951, Astronomical Journal 57 (1951): 3. 25. George Gamow, “Rotating Universe?” Nature 158 (1946): 549. 26. Gerard de Vaucoulers, “The Local Supercluster of Galaxies,” Soviet Astronomy 3, no. 6 (1960): 901. The Rus­sian version was published in 1959. 27. Heber D. Curtis, “The Nebulae,” in Handbuch der Astrophysik, vol. 2 (Berlin: Springer, 1933), 774. 28. Vera Rubin, interview by Lightman. 29. M. L. Humason, N. U. Mayall, and A. R. Sandage, “Redshifts and Magnitudes of Extragalactic Nebulae,” Astronomical Journal 61 (1956): 97–162. 30. Vera Rubin file, Cornell University. 31. Curvin H. Gingrich, “The Eighty-­fourth Meeting of the American Astronomical Society,” Popu­lar Astronomy 59 (1951): 57–65. 32. Gingrich, “The Eighty-­fourth Meeting.” 33. B. Sponberg, with P. Routly and J. S. Tenn, “Meetings of the AAS: 1948–51,” American Astronomical Society Historical Astronomy Division, https://­had​.­aas​.­org​/­resources​/­aashistory​/­early​-­meetings​/­1948​-­1951. 34. David DeVorkin, ed., The American Astronomical Society’s First ­Century (Washington, DC: American Institute of Physics, 1999). 35. Jeremiah P. Ostriker, “Biographical Memoir of Martin Schwarzschild 1912–1997,” National Acad­emy of Sciences, 2013, http://­w ww​.­nasonline​.­org​ /­publications​/­biographical​-­memoirs​/­memoir​-­pdfs​/­schwarzschild​-­martin​.­pdf. 36. Martin Schwarzschild to Vera Rubin, January 17, 1951, box 29, folder 1, Vera Rubin Papers. 37. Vera Rubin to Martin Schwarzschild, February 14, 1951, box 29, folder 1, Vera Rubin Papers. 38. Vera Cooper Rubin, “Differential Rotation of the Inner Metagalaxy,” Astronomical Journal 56, no. 1190 (April 1951): 47–48.

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39. Edwin Carpenter to Vera Rubin, March 14, 1951, box 29, folder 1, Vera Rubin Papers. 40. Vera Rubin, Bright Galaxies, Dark M ­ atters (Woodbury, NY: American Institute of Physics, 1997), 199. 4 1. Martin Schwarzschild to Vera Rubin, August 20, 1952, box 82, folder 5, Vera Rubin Papers. 42. Vera Rubin to Martin Schwarzschild, November 5, 1986, box 82, folder 5, Vera Rubin Papers. 4 . G E O R G E T OW N , G A M OW A N D G A L A X I E S

1. Vera Rubin, interview by David DeVorkin, May 9, 1996, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­a ip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​/­oral​ -­histories​/­5920​-­2. Much material in this chapter, not referenced to other sources, has made use of information in the online transcript of this interview. 2. “APL and the VT Fuze,” APL Technical Digest, September–­October 1962, 18–22, https://­w ww​.­jhuapl​.­edu​/­Content​/­techdigest​/­pdf​/­A PL​-­V02​-­N01​/­A PL​ -­02​-­01​-­V Tfuze​.­pdf. 3. Helen E. Worth, “The Visionary Directors of APL: Creating and Nurturing a National Resource,” Johns Hopkins APL Technical Digest 34, no. 2 (2018): 333–348, https://­w ww​.­jhuapl​.­edu​/­Content​/­techdigest​/­pdf​/­V34​-­N02​/­34​-­02​ -­Worth​-­Directors​.­pdf. 4. James R. Schatz and Harry K. Charles Jr., “APL’s Research Organ­ization: Then and Now,” Johns Hopkins APL Technical Digest 34, no. 2 (2018): 256–267, https://­w ww​.­jhuapl​.­edu​/­Content​/­techdigest​/­pdf​/­V34​-­N02​/­34​-­02​ -­Schatz​.­pdf. 5. Ralph A. Alpher and Robert Herman, Genesis of the Big Bang (Oxford: Oxford University Press, 2001), 77. 6. Karl Hufbauer, “George Gamow 1904–1968: A Biographical Memoir” (Washington, DC: National Acad­emy of Sciences, 2009). 7. Merle Tuve, interview by Charles Weiner, March 30, 1967, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­a ip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​/­oral​ -­histories​/­4920. 8. Alpher and Herman, Genesis of the Big Bang, 68–77. 9. Ralph A. Alpher, Hans Bethe, and George Gamow, “The Origin of Chemical Ele­ments,” Physical Review 73 (1948): 803–904. Although Alpher and Gamow made assumptions that ­later proved to be incorrect, the paper was an impor­tant first step in understanding the very early universe.

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10. George Gamow, The Creation of the Universe (New York: The Viking Press, 1952), 65. 11. Ralph A. Alpher and Robert C. Herman, “Evolution of the Universe,” Nature 162 (1948): 774–775. Alpher and Herman predicted that the left-­over radiation would have cooled to a temperature of about 5 K, with a peak intensity in the micro­wave region of the spectrum. This cosmic micro­wave background radiation was first detected in 1964 by Arno Penzias and Robert Wilson at the Bell Telephone Laboratories in Holmdel, New Jersey. For their discovery they received the Nobel Prize in Physics in 1978. The best mea­sured value of the temperature of the radiation is 2.7 K. 12. Ernest P. Gray and Albert M. Stone, “The History of the APL Colloquium,” APL Technical Digest 10 no. 2 (1989): 118. https://­w ww​.­jhuapl​.­edu​/­Content​ /­techdigest​/­pdf​/­V10​-­N02​/­10​-­02​-­Gray​.­pdf. 13. Annals of the Astronomical Observatory of Georgetown College, D. C. No. 1. Containing the Description of the Observatory, and the Description of the Use of the Transit Instrument, and Meridian Circle, (New York: Edward Dunigan & ­Brother, 1852). 14. Charles W. Wardlaw, “Re: Georgetown University Observatory Building,” typewritten memorandum, 1952. Old Archives: Observatory, Box 2 (1947–1971), GTA-000320-­DS. Booth F ­ amily Center for Special Collections, Georgetown University Archives. 15. Amelia Manning, “Dean of Astronomers,” Washington Star Magazine, March 14, 1965. Newspaper cutting. Old Archives: Heyden, Francis J., S.J., Box 15, GTA-000320-­DS. Booth F ­ amily Center for Special Collections, Georgetown University Archives. 16. Martin F. McCarthy SJ, and Jaylee M. Mead, “Obituary of Francis J. Heyden, S. J. (1907–1991),” Bulletin of the American Astronomical Society 24, no. 4 (1992): 1325–1326. 17. Vera C. Rubin, “Charlotte Moore Sitterly,” Journal of Astronomical History and Heritage 13, no. 2 (2010): 145–148. 18. Alpher and Herman, Genesis of the Big Bang, 70. 19. George Gamow, “The Role of Turbulence in the Evolution of the Universe,” Physical Review 86 (1952): 251. 20. George Gamow to Ralph Alpher, August 5, 1952, box 100, folder 10, Vera C. Rubin Papers, Manuscript Division, Library of Congress (hereafter Vera Rubin Papers). 21. Martin Schwarzschild to Vera Rubin, August 20, 1952, box 82, folder 5, Vera Rubin Papers. 22. George Gamow to Ralph Alpher, August 29, 1952, box 1, folder 1 (1949–1961), George Gamow and Barbara Gamow Papers, Manuscript Division, Library of Congress.

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23. Vera Rubin, note to ­daughter Judy on her 40th birthday, September 15, 1992, box 105, folder 6, Vera Rubin Papers. 24. Vera Rubin, “An Unconventional ­Career,” in Rubin, Bright Galaxies, Dark ­Matters (Woodbury, NY: American Institute of Physics, 1997), 155. 25. Lawrence H. Aller, “Leo Goldberg,” Biographical Memoirs, vol. 72 (Washington, DC: National Acad­emy Press, 1997), 114–134. 26. Owen Gingerich, “The Summer of 1953: A Watershed for Astrophysics,” Physics ­Today 47, no. 12 (1994): 34–40. 27. Allan Sandage, Centennial History of the Car­ne­gie Institution of Washington, vol. 1: The Mount Wilson Observatory (Cambridge: Cambridge University Press, 2005), 380. 28. W. Baade, “The Resolution of Messier 32, NGC 205 and the Central Region of the Andromeda Nebula,” Astrophysical Journal, 100 (1944): 137–146. 29. Donald E. Osterbrock, “Walter Baade, Observational Astrophysicist, (3): Palomar and Göttingen 1948–1960 (Part B),” Journal for the History of Astronomy 29, no. 4 (1998): 345–377. 30. Ernest Barker and Leo Goldberg to Vera Rubin, 1953, box 29, folder 1, Vera Rubin Papers. 31. Gingerich, “The Summer of 1953.” 32. Donald E. Osterbrock, Walter Baade: A Life in Astrophysics (Prince­ton: Prince­ton University Press, 2001), ch. 7. 33. Vera Rubin, “Intuition and Inspiration Made Gamow a Star Turn,” Nature 415 (2002): 13. 34. Osterbrock, Walter Baade: A Life, 180. 35. Vera C. Rubin, “An In­ter­est­ing Voyage,” Annual Review of Astronomy and Astrophysics 49 (2011): 1–28, 3. 36. Gingerich, “The Summer of 1953.” 37. Gingerich, “The Summer of 1953.” 38. George Gamow, “On the Formation of Protogalaxies in the Turbulent Primordial Gas,” Proceedings of the National Acad­emy of Sciences 40, no. 6 (1954): 480–484. 39. George Gamow to Vera Rubin, vari­ous correspondence, box 29, folder 1, and box 100, folder 10, Vera Rubin Papers. 40. D. Nelson Limber, “The Analy­sis of Counts of the Extragalactic Nebulae in Terms of a Fluctuating Density Field,” Astrophysical Journal 117 (1953): 134–144. 4 1. D. Nelson Limber, “The Analy­sis of Counts of the Extragalactic Nebulae in Terms of a Fluctuating Density Field II,” Astrophysical Journal 119 (1954): 655–681. 42. George Gamow to Vera Rubin, vari­ous correspondence, box 100, folder 10, Vera Rubin Papers.

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43. Harlow Shapley to Vera Rubin, July 12, 1954, box 29, folder 1, Vera Rubin Papers. 4 4. Vera Cooper Rubin, “Fluctuations in the Space Distribution of the Galaxies,” Proceedings of the National Acad­emy of Sciences 40 (1954): 541–549. 45. John Barrow, The Book of Universes (London: Bodley Head, 2011), 152. 46. Vera Rubin, in “PK9 Mail Bag,” Washington Post, February 5, 1954. 47. “­Mother of 2 at 25 to Receive Her Doctorate in Astronomy,” Washington Post, May 21, 1954. 48. “­Mother of 2 at 25 to Receive Her Doctorate.” 5 . A P R O F E S S I O N A L A S T R O N O M E R AT L A S T

1. Vera met Nancy Roman and Nancy Boggess at the Michigan Symposium, which all three ­women attended in 1953 (Chapter 4). Both Roman and Boggess l­ater went on to have c­ areers with NASA, where they influenced the development of telescopes in space. 2. Owen Gingerich, “The Discovery of the Spiral Arms of the Milky Way,” in The Milky Way Galaxy: Proceedings of the 106th IAU Symposium, Groningen, Netherlands, May 30–­June 3, 1983, ed. Hugo Van Woerden, Ronald J. Allen, W. Butler Burton (Dordrecht: D. Reidel, 1985), 59–70. 3. W. W. Morgan, Stuart Sharpless, and Donald Osterbrock, “Some Features of Galactic Structure in the Neighborhood of the Sun,” Astronomical Journal 57 (1952): 3. 4. Harold I. McEwen and Edward M. Purcell, “Radiation from Galactic Hydrogen at 1,420 MHz,” Nature 168 (1951): 356. 5. J. H. Oort, “Spiral Structure and Interstellar Radio Emission,” Monthly Notices of the Astronomical Society of South Africa 11 (1952): 65. 6. H. C. van de Hulst, C. A. Muller, and J. H. Oort, “The Spiral Structure of the Outer Part of the Galactic System Derived from the Hydrogen Emission at 21 cm Wave Length,” Bulletin of the Astronomical Institutes of the Netherlands 12, no. 452 (1954): 117. 7. Vera Rubin, “Galactic Radio Frequency Radiation,” unpublished manuscript, April 1953, box 105, folder 11, Vera C. Rubin Papers, Manuscript Division, Library of Congress (hereafter Vera Rubin Papers). 8. Vera Rubin, interview by David DeVorkin, May 9, 1996, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­aip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​/­oral​-­histories​/­5920​-­2. 9. Vera Rubin, “The Form of the Galactic Spiral Arms from a Modified Oort Theory,” Astronomical Journal 60 (1955): 177. 10. Montgomery Ju­nior College to Vera Rubin, September 20, 1954, box 29, folder 1, Vera Rubin Papers.

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11. Montgomery Ju­nior College to Vera Rubin, May 23, 1955, box 29, folder 2, Vera Rubin Papers. 12. Francis X. Quinn, “The Georgetown University Observatory,” Woodstock Letters 58, no. 4 (1959): 353–365. 13. Quinn, “Georgetown University Observatory.” 14. Copy of Application for Federal Employment completed by Vera Rubin, 1957, box 95, folder 3, Vera Rubin Papers. 15. Francis Heyden to Vera Rubin, November 18, 1956, box 29, folder 2, Vera Rubin Papers. 16. Francis Heyden to Vera Rubin, January 7, 1957, box 29, folder 2, Vera Rubin Papers. 17. Vera Rubin, draft of letter to Carl Kiess, June 27, 1957, box 95, folder 3, Vera Rubin Papers. 18. Vera Rubin, draft of letter to Carl Kiess, June 27, 1957. 19. Vera Rubin, draft of letter to Dr. D. E. Mann, undated, box 95, folder 3, Vera Rubin Papers. 20. Vera Rubin, draft of letter to Dr. F. K. Edmondson, undated, box 95, folder 3, Vera Rubin Papers. 21. President of Vassar College to Vera Rubin, January 17, 1958, box 29, folder 3, Vera Rubin Papers. 22. Vera Rubin, “Solar Limb Darkening Determined from Eclipse Observations,” Astrophysical Journal 129 (1959): 812–825. 23. Francis Heyden, Georgetown Observatory Report for 1959–60. Old Archives: Observatory, Box 2 (1947–1971), GTA-000320-­DS. Booth ­Family Center for Special Collections, Georgetown University Archives. 24. Vera Rubin, draft CV attached to NSF grant application, 1960, box 29, folder 3, Vera Rubin Papers. 25. The work on the spectrum of iron resulted in C. C. Kiess, V. C. Rubin, and C. E. Moore, “Faint Lines in the Arc Spectrum of Iron (Fe I),” Journal of Research of the National Bureau of Standards A: Physics and Chemistry 65A, no. 1 (1961): 1–29. 26. Gérard de Vaucouleurs, interview by Alan Lightman, November 7, 1988, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­a ip​.­org​/­history​-­programs​/­niels​ -­bohr​-­library​/­oral​-­histories​/­33930. 27. Harlow Shapley and Adelaide Ames, “Photometric Survey of the Nearer Extragalactic Nebulae,” Harvard College Observatory Bulletin, no. 887 (1932): 1–6. 28. Gérard de Vaucouleurs, “Evidence for a Local Supergalaxy,” Astronomical Journal 58, no. 1205 (1953): 30–32. 29. De Vaucouleurs, interview by Lightman.

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30. Gérard de Vaucouleurs, interview by Ronald Doel, November 23, 1991, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­aip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​ /­oral​-­histories​/­31929​-­2. 31. Gerard de Vaucouleurs, “The Local Supercluster of Galaxies,” Soviet Astronomy 3, no. 6 (1960): 901. The Rus­sian version was published in 1959. 32. Vera Rubin to G. de Vaucouleurs, March 5, 1958, box 29, folder 3, Vera Rubin Papers. 33. G. de Vaucouleurs to Vera Rubin, March 15, 1958, box 29, folder 3, Vera Rubin Papers. 34. G. de Vaucouleurs to Vera Rubin, February 24, 1959, box 29, folder 3, Vera Rubin Papers. 35. G. de Vaucouleurs, “Recherches sur les nébuleuses extragalactiques. I. Sur la technique de l’analyse microphotométrique des nébuleuses brillantes,” Annals d’Astrophysique 11 (1948): 247–287. 36. G. de Vaucouleurs to Vera Rubin, May 7, 1959, box 29, folder 3, Vera Rubin Papers. The ONR was prob­ably the Office of Naval Research. 37. Vera Rubin to G. de Vaucouleurs, May 20, 1959, box 29, folder 3, Vera Rubin Papers. 38. G. de Vaucouleurs to Vera Rubin, May 22, 1959, box 29, folder 3, Vera Rubin Papers. 39. Les Houches School of Physics, “History of the School,” https://­w ww​ .­houches​-­school​-­physics​.­com​/­the​-­school​/­history​/­. 40. Emily Mitchell, “Cécile DeWitte-­Morette,” Se­nior ­Women Web Interviews, 2001, http://­w ww​.­seniorwomen​.­com​/­articles​/­articlesIntCecile​.­html. 4 1. Vera C. Rubin, “An In­ter­est­ing Voyage,” Annual Review of Astronomy and Astrophysics 49 no. 1 (2011): 1–28, 6. 42. Rubin, “An In­ter­est­ing Voyage,” 7. 43. Vera Rubin to F. K. Edmondson, January 21, 1960, box 29, folder 3, Vera Rubin Papers. 4 4. G. de Vaucouleurs to Vera Rubin, October 13, 1959, box 29, folder 3, Vera Rubin Papers. 45. Vera Rubin to G. de Vaucouleurs, January 21, 1960, box 29, folder 3, Vera Rubin Papers. 46. Rudd Canaday, “Burroughs E101—­A Weird Computer,” blog post, May 4, 2014, http://­w ww​.­ruddcanaday​.­com​/­burroughs​-­e101​/­, accessed October 7, 2018. 47. Vera Rubin to G. de Vaucouleurs and F. K. Edmondson, January 21, 1960, box 29, folder 3, Vera Rubin Papers. 48. Donald C. Morton, “The 1960 Summer Course at Nyenrode ­Castle,” oral pre­sen­ta­tion at Blaauw 100 Symposium, Groningen, 2014, http://­w ww​.­astro​ .­rug​.­nl​/­~khan​/­blaauw100​/­presentations​/­D1​-­Morton​.­pdf.

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49. Vera Rubin, Bright Galaxies, Dark M ­ atters (Woodbury, NY: American Institute of Physics, 1997), 1. 50. Rubin, “An In­ter­est­ing Voyage,” 7. 51. Vera Rubin, “Structure and Evolution of the Galactic System,” Physics ­Today 13, no. 12 (1960): 32–35. 52. Rubin, Bright Galaxies, Dark M ­ atters, 1. 53. Rubin, “An In­ter­est­ing Voyage,” 7. 54. Vera Rubin to G. de Vaucouleurs, October 22, 1960, box 29, folder 3, Vera Rubin Papers. 55. G. de Vaucouleurs to Vera Rubin, February 4, 1961, box 29, folder 4, Vera Rubin Papers. 56. Vera Rubin to G. de Vaucouleurs, November 12, 1960, box 195, folder 6, Vera Rubin Papers. 57. Vera Rubin to G. de Vaucouleurs, February 10, 1961, box 195, folder 6, Vera Rubin Papers. 58. G. de Vaucouleurs to Vera Rubin, February 17, 1961, box 29, folder 4, Vera Rubin Papers. 59. G. de Vaucouleurs to Vera Rubin, May 22, 1959, box 29, folder 3, Vera Rubin Papers. 60. G. de Vaucouleurs to Vera Rubin, February 17, 1961. box 29, folder 4, Vera Rubin Papers. 61. Vera Rubin to G. de Vaucouleurs, October 9, 1963, box 29, folder 6, Vera Rubin Papers. 6. THE CALL OF THE DOME

1. Vera Rubin to G. de Vaucouleurs, February 10, 1961, box 195, folder 6, Vera C. Rubin Papers, Manuscript Division, Library of Congress (hereafter Vera Rubin Papers). 2. G. C. McVittie, letter to members of the AAS, June / July 1961, box 29, folder 4, Vera Rubin Papers. 3. Thomas E. Corbin, “Clayton A. Smith (1934–1993),” obituary, Bulletin of the American Astronomical Society 25 (1993): 1499. 4. Wayne H. Warren, “Jaylee M. Mead (1929–2012),” obituary, Bulletin of the American Astronomical Society 49 (2017): 36. Jaylee Mead’s husband, Gilbert, was a physicist at Goddard Space Flight Center, where they met, and heir to the im­mense Mead f­ amily fortune. ­A fter their retirements from NASA, they set up a philanthropic foundation and became major patrons of the performing arts. 5. Vera C. Rubin, “An In­ter­est­ing Voyage,” Annual Review of Astronomy and Astrophysics 49 (2011): 1–28, 6.

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6. Johannes Kepler, Harmonices Mundi [The Harmony of the World] (Linz, Austria: Johann Planck, 1619), book 5, chapter 3, p. 189. Kepler’s third law of planetary motion states that the square of the orbital period of a planet is directly proportional to the cube of the semi-­major axis of its elliptical orbit. 7. Jaylee Burley to Vera Rubin, July 12, 1961, box 29, folder 4, Vera Rubin Papers. 8. Rubin, “An In­ter­est­ing Voyage,” 7. 9. G. de Vaucouleurs to O. Heckmann, April 19, 1991; O. Heckmann to symposium invitees, March 7, 1961, box 29, folder 4, Vera Rubin Papers. 10. Jerzy Neyman, Thornton Page, and Elizabeth Scott, “Conference on the Instability of Systems of Galaxies,” Astronomical Journal 66 (1961): 533–535. 11. E. Margaret Burbidge, “The Mea­sure­ment of Rotation in Spiral, Irregular and S0 Galaxies,” in Prob­lems of Extra-­Galactic Research: Proceedings from IAU Symposium no. 15, ed. G. C. McVittie (New York: Macmillan, 1962), 85–104. 12. Geoffrey Burbidge, interview by David DeVorkin, October 21, 1977, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­aip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​ /­oral​-­histories​/­33264. 13. E. Margaret Burbidge, interview by David DeVorkin, July 13, 1978, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­aip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​/­oral​-­histories​ /­25487. 14. Edward Spiegel, “Kevin Prendergast (1929–2004),” obituary, Bulletin of the American Astronomical Society 37 (2005): 1555. 15. Kevin Prendergast, “The Determination of the Masses of Galaxies and Their Internal Mass Distributions,” in Prob­lems of Extra-­Galactic Research: Proceedings from IAU Symposium no. 15, ed. G. C. McVittie (New York: Macmillan, 1962), 126–136. 16. Abstracts of papers presented at the 111th AAS meeting, Astronomical Journal 67 (1962): 281. 17. Vera C. Rubin, Jaylee Burley, Ahmad Kiasatpoor, Benny Klock, Gerald Pease, Erich Rutsheidt, and Clayton Smith, “Kinematic Studies of Early-­ Type Stars. I. Photometric Survey, Space Motions, and Comparison with Radio Observations,” Astronomical Journal 67 (1962): 491–531. 18. Rubin, “An In­ter­est­ing Voyage,” 7. 19. K. Rohlfs, R. Chini, J. E. Wink, and R. Böhme, “The Rotation Curve of the Galaxy,” Astronomy and Astrophysics 158 (1986): 181–190. 20. George Coyne and Vera Rubin, “Martin F. McCarthy S.J. (1923–2010),” obituary, Bulletin of the American Astronomical Society 43 (2011): 19. 21. George Coyne, “One Last Story about Vera Rubin,” The Catholic Astronomer, January 14, 2017, https://­w ww​.­vofoundation​.­org​/­blog​/­tag​/­george​

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-­coyne​/­; George Coyne, telephone conversation with Jacqueline Mitton, January 8, 2019. 22. Vera Rubin to Helmut Abt, June 4, 1963, box 29, folder 7, Vera Rubin Papers. 23. Martin McCarthy and Vera Rubin, “Classification of G Type Stars in the Near Ultraviolet Region,” Ricerche Astronomiche Specola Vaticana 6 (1963): 431–439. 24. Martin McCarthy, untitled manuscript undated [1993], box 160, folder 5, Vera Rubin Papers. 25. “Glenn with Vera Rubin and Martin McCarthy, S.J., Professor of Astronomy,” January 11, 1963, Booth ­Family Center for Special Collections, Georgetown University Archives, https://­w ww​.­library​.­georgetown​.­edu​ /­special​-­collections​/­archives​/­john​-­glenn​-­visits​-­georgetown. 26. Martin McCarthy and Vera Rubin, “Classification of G Type Stars in the Near Ultraviolet Region” (abstract), Astronomical Journal 68 (1963): 285. 27. Rubin, “An In­ter­est­ing Voyage,” 8. Rubin’s recollection that the AAS meeting at which she spoke to the Burbidges was in Phoenix in 1962 is incorrect; ­there was no such meeting. 28. Martin McCarthy to Geoffrey Burbidge, May 28, 1963, box 29, folder 6, Vera Rubin Papers. 29. Vera Rubin to Helmut Abt, June 4, 1963, box 29, folder 7, Vera Rubin Papers. 30. Vera C. Rubin, “Radial Velocities of Distant OB Stars in the Anticenter Region of the Galaxy,” Astrophysical Journal 142 (1965): 934–942. 31. Martin McCarthy to Judy Rubin, July 28, 1963, box 103, folder 1, Vera Rubin Papers. 32. Harold Hartley, “Maine’s Eclipse Is Like Race Day in Indianapolis,” Indianapolis Times, July 20, 1963. 33. Rubin, “An In­ter­est­ing Voyage,” 8. 34. Martin McCarthy to Vera Rubin, September 3, 1963 (letter 1), box 53, folder 3, Vera Rubin Papers. 35. Martin McCarthy to Vera Rubin, September 3, 1963 (letter 2), box 53, folder 3, Vera Rubin Papers. 36. Rubin, “An In­ter­est­ing Voyage,” 8. 37. Rubin, “An In­ter­est­ing Voyage,” 8. 38. (1) E. M. Burbidge, G. R. Burbidge, D. J. Crampin, V. C. Rubin, and K. H. Prendergast, “The Rotation and Mass of NGC 6503,” Astrophysical Journal 139 (February 1964): 539; (2) E. M. Burbidge, G. R. Burbidge, D. J. Crampin, V. C. Rubin, and K. H. Prendergast, “The Rotation and Mass of NGC 3521,” Astrophysical Journal 139 (May 1964): 1058; (3) V. C. Rubin, E. M. Burbidge, G. R. Burbidge, and K. H. Prendergast, “The Rotation and Mass

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of NGC 1792,” Astrophysical Journal 140 (July 1964): 539; (4) E. M. Burbidge, G. R. Burbidge, V. C. Rubin, and K. H. Prendergast, “Motions in Barred Spirals. VI. The Rotation and Velocity Field of NGC 613,” Astrophysical Journal 140 (July 1964): 85; (5) V. C. Rubin, E. M. Burbidge, and G. R. Burbidge, “Motions in Barred Spirals. VII. The Velocity Field of NGC 925,” Astrophysical Journal 140 (July 1964): 94; (6) E. M. Burbidge, G. R. Burbidge, and V. C. Rubin, “A Study of the Velocity Field in M82 and Its Bearing on Explosive Phenomena in That Galaxy,” Astrophysical Journal 140 (October 1964): 942; (7) V. C. Rubin, E. M. Burbidge, and G. R. Burbidge, “NGC 2188, a Peculiar Southern Galaxy,” Astrophysical Journal 140 (October 1964): 1304; (8) V. C. Rubin, E. M. Burbidge, G. R. Burbidge, D. J. Crampin, and K. H. Prendergast, “The Rotation and Mass of NGC 7331,” Astrophysical Journal 141 (February 1965): 759; (9) V. C. Rubin, E. M. Burbidge, G. R. Burbidge, and K. H. Prendergast, “The Rotation and Mass of the Inner Parts of NGC 4826,” Astrophysical Journal 141 (April 1965): 885. Note: Both Margaret Burbidge and Joan Crampin w ­ ere known by their ­middle names rather than the first of their given names, which ­were Eleanor and Dorothy, respectively. 39. Vera Rubin to Sarah Lee Lippincott, October 15, 1963, box 19, folder 6, Vera Rubin Papers. 40. Martin McCarthy to Vera Rubin, October 17, 1963, box 53, folder 3, Vera Rubin Papers. 4 1. Francis Heyden, “Georgetown Observatory,” in “Reports from Observatories,” Astronomical Journal 69 (1964): 658. 42. Francis Heyden to Vera Rubin, November 4, 1963, box 29, folder 6, Vera Rubin Papers. 43. Martin McCarthy to Vera Rubin, November 27, 1963, box 53, folder 3, Vera Rubin Papers. 4 4. Francis Heyden to Vera Rubin, January 29, 1964, box 29, folder 7, Vera Rubin Papers. 45. Francis Heyden to Vera Rubin, April 20, 1964, box 29, folder 7, Vera Rubin Papers. 46. Correspondence between Vera Rubin and Maud Makemson, 1964, box 94, folder 13, Vera Rubin Papers. 47. Vera Rubin to William C. Kelly, American Institute of Physics, September 28, 1964, box 29, folder 7, Vera Rubin Papers. 48. Rubin, “An In­ter­est­ing Voyage,” 8. 49. Martin McCarthy to Vera Rubin, September 24–28, 1964, box 8, folder 5, Vera Rubin Papers. 50. Vera Rubin, “E. Margaret Burbidge,” Science 211 (February 27, 1981): 915–916.

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51. E. Margaret Burbidge, “Watcher of the Skies,” Annual Review of Astronomy and Astrophysics 32 (1994): 1–36. 52. Vera Rubin to Allan Sandage, October 17, 1964, box 53, folder 1, Vera Rubin Papers. 53. Allan Sandage to Vera Rubin, December 2, 1964, box 53, folder 1, Vera Rubin Papers. 54. Horace W. Babcock to Vera Rubin, February 1, 1965, box 53, folder 1, Vera Rubin Papers. 55. Vera Rubin to Horace W. Babcock, February 8, 1965, box 53, folder 1, Vera Rubin Papers. 56. Vera Rubin to Allan Sandage, February 8, 1965, box 53, folder 1, Vera Rubin Papers. 57. Vera Rubin to Dean James B. Horigan SJ, January 13, 1965, box 29, folder 8, Vera Rubin Papers. 58. Martin McCarthy to Vera Rubin, January 29, 1965, box 29, folder 8, Vera Rubin Papers. 59. Martin McCarthy to Vera Rubin, February 22, 1965, box 103, folder 2, Vera Rubin Papers. 7. T H E D E L I G H T O F D I S COV E RY

1. Vera Rubin, interview by Carol A. Mockros, October 10, 1992, unpublished transcript, box 95, folder 8, Vera C. Rubin Papers, Manuscript Division, Library of Congress (hereafter Vera Rubin Papers). 2. Since 2007, the Car­ne­gie Institution of Washington has operated ­u nder the name “Car­ne­g ie Institution for Science,” although its l­egal name remains unchanged. In 2020, the Institution merged the DTM with its Geophysical Laboratory (already on the same site) to form the Earth and Planets Laboratory. 3. Car­ne­gie Institution of Washington Year Book 64 (1964–1965). 4. Vera Rubin, interview with Carl Lankowski and Pam Lankowski, November 5, 2011, Oral Histories, Historic Chevy Chase DC, https://­w ww​ .­historicchevychasedc​.­org​/­oral​-­histories​/­vera​-­rubin​/­. 5. Vera C. Rubin, “An In­ter­est­ing Voyage,” Annual Review of Astronomy and Astrophysics 49 (2011): 1–28, 9. 6. W. Kent Ford Jr., interview by David DeVorkin and Shaun Hardy, October 25, 2013, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­a ip​.­org​/­history​-­programs​/­niels​ -­bohr​-­library​/­oral​-­histories​/­43241. 7. “Report of the President,” in Car­ne­gie Institution of Washington Year Book 64 (1964–1965), 33.

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8. “Department of Terrestrial Magnetism,” in Car­ne­gie Institution of Washington Year Book 64 (1964–1965), 345. 9. Martin McCarthy to Vera Rubin, March 13, 1965, box 103, folder 3, Vera Rubin Papers. 10. “Committee on Image Tubes for Telescopes,” in Car­ne­gie Institution of Washington Year Book 64 (1964–1965), 361. 11. Vera Rubin to Rev. Brian A. McGrath SJ, March 10, 1965, box 29, folder 8, Vera Rubin Papers. 12. W. Kent Ford Jr., interview by David DeVorkin and Shaun Hardy. 13. Vera Rubin, quoted in Barbara Spector, “A Love of Science: Do Parents Pass It Along to their ­Children?” The Scientist 5, no. 19 (September 30, 1991). 14. Allan Rubin, quoted in Rubin, “An In­ter­est­ing Voyage,” 27. 15. Rubin, “An In­ter­est­ing Voyage,” 21–22. 16. Janet Land, “Vera Rubin: One of the DTM’s Star Scientists,” Car­ne­gie Institution Newsletter, November 1974. 17. Vera Rubin, interview by Carol A. Mockros. 18. Vera Rubin to Harlan Smith, November 25, 1964, box 29, folder 7, Vera Rubin Papers. 19. E. Margaret Burbidge, “Watcher of the Skies,” Annual Review of Astronomy and Astrophysics 32 (1994): 1–36. 20. Martin McCarthy to Vera Rubin, March 7, 1965, box 29, folder 8, Vera Rubin Papers. 21. “Department of Terrestrial Magnetism,” in Car­ne­gie Institution Year Book 64, 360. 22. W. Kent Ford Jr., interview by David DeVorkin and Shaun Hardy. 23. K. I. Kellermann, “The Discovery of Quasars,” Bulletin of the Astronomical Society of India 41 (2013): 1–17. 24. Jesse L. Greenstein, “The Early Years of Radio Astronomy at Caltech,” Australian Journal of Physics 47 (1994): 555–560. 25. T. A. Matthews and A. R. Sandage, “Optical Identification of 3C 48, 3C 196 and 3C 286 with Stellar Objects,” Astrophysical Journal 138 (1963): 30–56. 26. C. ­Hazard, M. B. Mackey, and A. J. Shimmins, “Investigation of the Radio Source 3C 273 by the Method of Lunar Occultations,” Nature 197 (1963): 1037–1039. 27. M. Schmidt, “3C 273: A Star-­Like Object with a Large Red-­Shift,” Nature 197 (1963): 1040. 28. A. R. Sandage, “The Existence of a Major New Constituent of the Universe: The Quasi-­Stellar Galaxies,” Astrophysical Journal 141 (1965): 1560–1578. 29. Vera Rubin to Margaret and Geoffrey Burbidge, May 31, 1965, box 29, folder 8, Vera Rubin Papers.

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30. E. Margaret Burbidge and G. R. Burbidge, “The Rotation and Physical Conditions in the Seyfert Galaxy NGC 7469,” Astrophysical Journal 137 (1963): 1022–1032. 31. Vera Rubin to Margaret and Geoffrey Burbidge, May 31, 1965. 32. Martin McCarthy to Vera Rubin, May 30, 1965, box 29, folder 8, Vera Rubin Papers. . 33. Vera Rubin to Margaret and Geoffrey Burbidge, May 31, 1965. 34. “Royal Greenwich Observatory and the Royal Observatory, Cape of Good Hope: Report for the 15 Months Ending 1966 June 30,” Quarterly Journal of the Royal Astronomical Society 7 (1966): 283. 35. Martin McCarthy to Vera Rubin, June 12, 1965, box 29, folder 8, Vera Rubin Papers. 36. Peter Boyce, telephone interview by Jacqueline Mitton, February 26, 2019. 37. Rubin, “An In­ter­est­ing Voyage,” 10. 38. Vera Rubin and W. Kent Ford Jr., “Low-­Dispersion Image Tube Spectra in the Red: 3C 33, 3C 48, Ton 256 and an Infrared Star,” Astrophysical Journal 142 (1965): 1303–1307. 39. Martin McCarthy to Vera Rubin, August 25, 1965, box 29, folder 8, Vera Rubin Papers. 40. The stars observed ­were R Leonis, R Hydrae, Mu Cephei, and Chi Cygni. M. F. McCarthy, P. Treanor, and W. Kent Ford Jr., “Image Tube Spectra of Late Type Stars,” in Colloquium on Late-­type Stars, Trieste, 1966, ed. Margherita Hack (Trieste: Osservatorio Astronomico, 1967), 100–108. 4 1. Vera Rubin to Martin McCarthy, August 18, 1965, box 29, folder 8, Vera Rubin Papers. 42. Martin McCarthy to Vera Rubin, August 25, 1965, box 29, folder 8, Vera Rubin Papers. 43. Martin McCarthy to Vera Rubin, May 30, 1965, box 29, folder 8, Vera Rubin Papers. 4 4. Martin McCarthy to Vera Rubin, September 20, 1965, box 29, folder 8, Vera Rubin Papers. 45. Rubin, “An In­ter­est­ing Voyage,” 9. 46. Vera Rubin to Horace Babcock, April 4, 1966, box 53, folder 1, Vera Rubin Papers. 47. “Department of Terrestrial Magnetism,” in Car­ne­gie Institution of Washington Year Book 65 (1965–1966), 69. 48. Rubin, “An In­ter­est­ing Voyage,” 12–13. 49. V. C. Rubin, S. Moore, and F. C. Bertiau, “Faint Blue Objects in the Virgo Cluster Region,” Astronomical Journal 72 (1967): 59–64. S. Moore is now better known as Sandra Faber. She spent time at DTM in 1966 when she was a gradu­ate student at Harvard.

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50. Sandra Faber, interview by Alan Lightman, October 15, 1988, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­a ip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​/­oral​ -­histories​/­33932. 51. “Sandra Moore Faber,” Contributions of 20th ­Century W ­ omen to Physics, http://­c wp​.­library​.­ucla​.­edu​/­Phase2​/­Faber,​_ ­Sandra ​_ ­Moore@931234567​.­html. and links to further sources contained therein. 52. Vera Rubin to H. W. Babcock, October 29, 1965, box 53, folder 1, Vera Rubin Papers. 53. H. W. Babcock to Vera Rubin, December 8, 1965, box 29, folder 8, Vera Rubin Papers. 54. Vera Rubin to H. W. Babcock, May 20, 1966, box 29, folder 9, Vera Rubin Papers. 55. V. C. Rubin and J. M. Losee, “A Finding List of Faint Blue Stars in the Anticenter Region of the Galaxy,” Astronomical Journal 76 (1971): 1099–1101; V. C. Rubin, D. Westpfahl, Jr., and M. Tuve, “Second Finding List of Faint Blue Stars in the Anticenter Region of the Galaxy,” Astronomical Journal 79 (1974): 1406–1409. 56. W. Kent Ford Jr to H. W. Babcock, November 9, 1965, box 53, folder 1, Vera Rubin Papers. 57. Allan Sandage to Vera Rubin, January 21, 1966, box 53, folder 1, Vera Rubin Papers. 58. “Department of Terrestrial Magnetism,” in Car­ne­gie Institution Year Book 65, 67. 59. Peter Boyce, interview with Jacqueline Mitton. 60. Vera Rubin, “Reminiscences: Observing at the National Facilities,” in A ­ atters Look at AURA 1994, reprinted in Rubin, Bright Galaxies, Dark M (Woodbury, NY: American Institute of Physics, 1997). 61. Vera Rubin, “Letter from Chile,” August 1971, in Rubin, Bright Galaxies, Dark ­Matters, 84–86. 62. J. D. H. Pilkington and P. F. Scott, “A Survey of Radio Sources between Declinations 20° and 40°,” Memoirs of the Royal Astronomical Society 69 (1965): 183. 63. Vera Rubin to Martin McCarthy, September 19, 1966, box 29, folder 9, Vera Rubin Papers 64. W. Kent Ford Jr., interview by David DeVorkin and Shaun Hardy. 65. Vera Rubin, “An Unconventional ­Career,” in Rubin, Bright Galaxies, Dark ­Matters, 153–163. 66. Rubin, “An In­ter­est­ing Voyage,” 10. 67. Walter Baade and Halton Arp, “Positions of Emission Nebulae in M31,” Astrophysical Journal 139 (1964): 1027.

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68. Rubin, “An In­ter­est­ing Voyage,” 12. 69. “Department of Terrestrial Magnetism,” in Car­ne­gie Institution of Washington Year Book 66 (1966–1967), 58. 8 . A DV E N T U R E S I N A N D R O M E DA

1. Vera C. Rubin, “An In­ter­est­ing Voyage,” Annual Review of Astronomy and Astrophysics 49 (2011): 1–28, 7. 2. “Department of Terrestrial Magnetism,” in Car­ne­gie Institution of Washington Year Book 63 (1963–1964): 341–348. 3. H. C. van de Hulst, E. Raimond, and H. van Woerden, “Rotation and Density Distribution of the Andromeda Nebula Derived from Observations of the 21-cm Line,” Bulletin of the Astronomical Institutes of the Netherlands 480 (1957): 1–16. 4. The parsec, abbreviated “pc,” is a peculiarly astronomical unit of distance, equivalent to 3.262 light years. The word is a contraction of “parallax-­ second.” A kiloparsec (kpc) is one thousand parsecs. 5. Morton S. Roberts, “A High-­Resolution 21-cm Hydrogen-­Line Survey of the Andromeda Nebula,” Astrophysical Journal 144 (1966): 639–656. 6. Vera C. Rubin, Jaylee Burley, Ahmad Kiasatpoor, Benny Klock, Gerald Pease, Erich Rutsheidt, and Clayton Smith, “Kinematic Studies of Early-­ Type Stars. I. Photometric Survey, Space Motions, and Comparison with Radio Observations,” Astronomical Journal 67 (1962): 491–531. 7. N. U. Mayall, “Comparison of Rotational Motions Observed in the Spirals M31 and M33 and in the Galaxy,” Publications of the Observatory of the University of Michigan 10 (1951): 19–24. 8. Roberts, “A High-­Resolution 21-cm Hydrogen-­Line Survey of the Andro­ meda Nebula.” 9. Rubin, “An In­ter­est­ing Voyage,” 8. 10. Vera C. Rubin, “One Hundred Years of Rotating Galaxies,” Publications of the Astronomical Society of the Pacific 112 (2000): 747–750. 11. Vera C. Rubin, “A C ­ entury of Galaxy Spectroscopy,” Astrophysical Journal 451 (1995): 419–428. 12. William Huggins, “On the Spectrum of Some of the Nebulae,” Philosophical Transactions of the Royal Society of London 154 (1864): 437–444. 13. Agnes Mary Clerke, The System of the Stars (London: Longmans, Green and Com­pany, 1890) 376. 14. James Edward Keeler, “Photo­graphs of Nebulae and Clusters, Made with the Crossley Reflector,” Publications of the Lick Observatory 8 (1908): 1. 15. J. Scheiner, “On the Spectrum of the G ­ reat Nebula in Andromeda,” Astrophysical Journal 9 (1899): 149–150.

280

N O T E S T O PA GE S 1 5 7 – 1 6 1

16. Rubin, “A ­Century of Galaxy Spectroscopy.” 17. H. Oleak to Vera Rubin, September 7, 1987, box 105, folder 2, Vera C. Rubin Papers, Manuscript Division, Library of Congress (hereafter Vera Rubin Papers). 18. V. M. Slipher, “The Radial Velocity of the Andromeda Nebula,” Lowell Observatory Bulletin 80 (1913): 59–62. 19. W. Campbell to V. Slipher April 9, 1913, Lowell Observatory archives, cited in R. W. Smith, “The Velocity-­Distance Relation,” Journal for the History of Astronomy 10 (1979): 133–165. 20. V. M. Slipher, “The Detection of Nebular Rotation,” Lowell Observatory Bulletin 2, no. 12 (1914): 12. 21. F. G. Pease, “The Rotation and Relative Velocity of the Central Part of the Andromeda Nebula,” Proceedings of the National Acad­emy of Sciences 4 (1918): 21–24. 22. Vera C. Rubin, “Multi-­spin Galaxies,” Astronomical Journal 108 (1994): 456–467. 23. Vera C. Rubin and W. Kent Ford Jr., “Rotation of the Andromeda Nebula from a Spectroscopic Observation of Emission Regions,” Astrophysical Journal 159 (1970): 379–403. 2 4. The mass-­to-­light (or mass-to-luminosity) ratio of a galaxy, or a region of a galaxy, is its total mass divided by its total luminosity, using the Sun’s mass and luminosity as the units. 25. “Another Universe Seen by Astronomer,” New York Times, January 22, 1926, 2. Edwin Hubble, The Realm of the Nebulae (New Haven: Yale University Press, 1936), 100, gives the figure as “less than a million light years.” 26. E. Öpik (Oepik), “An Estimate of the Distance of the Andromeda Nebula,” Astrophysical Journal 55 (1922): 406–410. 27. Rubin, “A ­Century of Galaxy Spectroscopy.” 28. E. P. Hubble, “Cepheids in Spiral Nebulae,” Publications of the American Astronomical Society 5 (1927): 261–264. 29. Horace W. Babcock, “The Rotation of the Andromeda Nebula,” Lick Observatory Bulletin 498 (1939): 41–51. 30. Allan Sandage, “Horace Welcome Babcock, 13 September 1912–29 August 2003,” Proceedings of the American Philosophical Society 150 (2006): 151–160. 31. William L. Vanderburgh, “Putting a New Spin on Galaxies: Horace W. Babcock, the Andromeda Nebula and the Dark ­Matter Revolution,” Journal for the History of Astronomy 45 (2014): 141–159. 32. Mayall, “Comparison of Rotational Motions.” 33. “Department of Terrestrial Magnetism,” in Car­ne­gie Institution of Washington Year Book 66 (1966–1967), 58.

N O T E S T O PA GE S 1 6 1 – 1 7 0 

281

34. Vera Rubin, “Seeing Dark ­Matter in the Andromeda Galaxy,” Physics ­Today 59, no. 12 (2006): 8–9. 35. Rubin, “An In­ter­est­ing Voyage,” 12. 36. Rubin, “An In­ter­est­ing Voyage,” 13. 37. Guido Münch, “Expanding Motions of Interstellar Gas in the Nuclear Region of M31,” Astrophysical Journal 131 (1960): 250–252. 38. A. Lallemand, M. Duchesne, and Merle F. Walker, “The Rotation of the Nucleus of M31,” Publications of the Astronomical Society of the Pacific 72 (1960): 76–84. 39. Vera C. Rubin and W. Kent Ford Jr., “Rotation of the Andromeda Nebula from a Spectroscopic Survey of Emission Regions,” Astrophysical Journal 159 (1970): 391–393, Figure 11, ­Tables 3 and 4. 40. “Department of Terrestrial Magnetism,” Car­ne­gie Institution Year Book 63, 342. 4 1. Rubin, “One Hundred Years of Rotating Galaxies.” 42. G. de Vaucouleurs, “General Physical Properties of External Galaxies,” in Astrophysics IV: Stellar Systems, Encyclopedia of Physics, vol. 11, ed. S. Flügge (Berlin: Springer, 1959), 311–372. 43. W. Kent Ford Jr., and Vera C. Rubin, “Spectra of Emission Regions in M31,” Bulletin of the American Astronomical Society 1 (1969): 188. 4 4. “American Astronomers Report,” Sky and Telescope 37 (March 1969): 147–149. 45. G. de Vaucouleurs, A. de Vaucouleurs, and M. De Cesare, “Rotation, Masses and Mean Densities of Nine Galaxies (abstract),” Bulletin of the American Astronomical Society 1 (1969): 186. 46. Donald E. Osterbrock, “Rudolph Leo Bernard Minkowski,” Biographical Memoirs 54 (Washington DC: National Acad­emy of Sciences, 1983), 270–298. 47. Rubin and Ford, “Rotation of the Andromeda Nebula.” 48. Maarten Schmidt, “Rotation Par­a meters and Distribution of Mass in the Galaxy,” in Galactic Structure, ed. A. Blaauw and M. Schmidt (Chicago: University of Chicago Press, 1965), 513. 49. S. T. Gottesman, R. D. Davies, and V. C. Reddish, “A Neutral Hydrogen Survey of the Southern Regions of the Andromeda Nebula,” Monthly Notices of the Royal Astronomical Society 133 (1966): 359–387. 50. R. D. Davies and S. T. Gottesman, “Neutral Hydrogen in M31—­I. The Distribution of Neutral Hydrogen,” Monthly Notices of the Royal Astronomical Society 149 (1970): 237–261. 51. S. T. Gottesman and R. D. Davies, “Neutral Hydrogen in M31—­II. The Dynamics and Kinematics of M31,” Monthly Notices of the Royal Astronomical Society 149 (1970): 263–290.

282

N O T E S T O PA GE S 1 7 1 – 1 7 8

52. J. E. Baldwin to Vera Rubin, November 17, 1969, box 30, folder 1, Vera Rubin Papers. 53. Vera Rubin to J. E. Baldwin, November 24, 1969, box 30, folder 1, Vera Rubin Papers. 54. J. M. Deharveng and A. Pellet, “Étude cinématique et dynamique de M31 à partir de l’observation des regions d’émission,” Astronomy and Astrophysics 38 (1975): 15–28. 55. D. T. Emerson, “High Resolution Observations of Neutral Hydrogen in M31—­II,” Monthly Notices of the Royal Astronomical Society 176 (1976): 321–343. 56. Morton S. Roberts and Robert Whitehurst, “The Rotation Curve and Geometry of M31 at Large Galactocentric Distances,” Astrophysical Journal 201 (1975): 327–346. 57. Stephen M. Kent, “A Comparison of Optical and HI Rotation Curves in M31,” Publications of the Astronomical Society of the Pacific 101 (1989): 489–493. 58. Vera C. Rubin and W. Kent Ford Jr., “Radial Velocities and Line Strengths of Emission Lines across the Nuclear Disk of M31,” Astrophysical Journal 170 (1971): 25–52. 59. G. Münch, “Motions of the Interstellar Gas in the Central Regions of Galaxies,” in Prob­lems of Extra-­Galactic Research, ed. G. C. McVittie (New York: Macmillan, 1962), 119. 60. G. W. Rougoor and J. W. Oort, “Distribution and Motion of Hydrogen in the Galactic System with Par­tic­u­lar Reference to the Region within 3 kiloparsecs of the Center,” Proceedings of the National Acad­emy of Sciences 46 (1960): 1–13. 61. Manuel Peimbert, “Physical Conditions in the Nuclei of M51 and M81,” Astrophysical Journal 154 (1968): 33–48. 9 . B R I G H T L I G H T O N DA R K M ­ AT T E R

1. Morton S. Roberts, “The Rotation Curves of Galaxies,” Comments on Astrophysics 6 (1976): 105–111. 2. The 4-­meter telescope at Cerro Tololo was named the Víctor M. Blanco Telescope in 1995. 3. Vera C. Rubin, “The Rotation of Spiral Galaxies,” Science 220 (1983): 1339–1344. 4. Louise Volders, “Neutral Hydrogen in M33 and M101,” Bulletin of the Astronomical Institutes of the Netherlands 14 (1959): 323–334. 5. Vera Rubin, “A ­Century of Galaxy Spectroscopy,” Astrophysical Journal 451 (1995): 419–428.

N O T E S T O PA GE S 1 7 8 – 1 8 1 

283

6. G. S. Shostak, “Aperture Synthesis Study of Neutral Hydrogen in NGC 2403 and NGC 4236,” Astronomy and Astrophysics 24 (1973): 411–419. 7. Marshall Cohen, “Dark M ­ atter and the Owens Valley Radio Observatory,” in The New Astronomy: Opening the Electromagnetic Win­dow and Expanding Our View of Planet Earth, ed. Wayne Orchiston (Dordrecht: Springer, 2005), 169–182. 8. D. H. Rogstad and G. S. Shostak, “Gross Properties of Five Scd Galaxies as Determined from 21-­centimeter Observations,” Astrophysical Journal 176 (1972): 315–321. 9. Thornton Page, “M / L for Double Galaxies: A Correction,” Astrophysical Journal 136 (1962): 685–686. 10. M. S. Roberts and A. H. Rots, “Comparison of Rotation Curves of Dif­fer­ent Galaxy Types,” Astronomy and Astrophysics 26 (1973): 483–485. 11. M. S. Roberts, “The Rotation Curves of Galaxies,” in International Astronomical Union Symposium 69: Dynamics of Stellar Systems, ed. A. Hayli (Dordrecht: Reidel, 1975), 331–340. 12. Vera Rubin, interview by David DeVorkin and Ashley Yeager, July 20, 2007, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­a ip​.­org​/­history​-­programs​/­niels​ -­bohr​-­library​/­oral​-­histories​/­4 4082. 13. Vera Rubin, “A Brief History of Dark ­Matter,” in The Dark Universe: M ­ atter, Energy and Gravity, ed. Mario Livio (Cambridge: Cambridge University Press 2004), 1–13. 14. Revd. John Michell, “On the Means of Discovering the Distance, Magnitude, &c. of the Fixed Stars,” Philosophical Transactions of the Royal Society, London 74 (1784): 35–57. 15. J. C. Kapteyn, “First Attempt at a Theory of the Arrangement and Motion of the Sidereal System,” Astrophysical Journal 55 (1922): 302–328. 16. J.  H. Jeans, Prob­lems of Cosmogony and Stellar Dynamics (Cambridge: Cambridge University Press, 1922), 239. 17. Edwin Hubble and Milton L. Humason, “The Velocity-­Distance Relation among Extra-­Galactic Nebulae,” Astrophysical Journal 74 (1931): 43–80. 18. F. Zwicky, “Die Rotverschiebung von extragalaktischen Nebeln,” Helvetica Physica Acta 6 (1933): 110–128. 19. F. Zwicky, “Republication of: The Redshift of Extragalactic Nebulae,” trans. Anita Ehlers, General Relativity and Gravitation 41 (2008): 207–224. 20. Sinclair Smith, “The Mass of the Virgo Cluster,” Astrophysical Journal 83 (1936): 23–30. 21. John Johnson, Zwicky: The Outcast Genius Who Unmasked the Universe (Cambridge, MA: Harvard University Press, 2019), 89–106.

284

N O T E S T O PA GE S 1 8 1 – 1 8 7

22. F. Zwicky, “On the Masses of Nebulae and Clusters of Nebulae,” Astrophysical Journal 86 (1937): 217–246. 23. M. Schwarzschild, “Mass Distribution and Mass-­Luminosity Ratio in Galaxies,” Astronomical Journal 59 (1954): 274–284. 24. Geoffrey Burbidge, “Acceleration of Cosmic-­R ay Particles among Extragalactic Nebulae,” Physical Review 101 (1957): 269–271. 25. Kenneth Freeman, “Dark ­Matter in Galaxies,” public lecture given at the University of Western Australia, Perth, August 14, 2008. 26. K. C. Freeman, “On the Disks of Spiral and S0 Galaxies,” Astrophysical Journal 160 (June 1970): 811–830. 27. D. W. Sciama, Modern Cosmology (Cambridge: Cambridge University Press, 1971), vii. 28. P. J. E. Peebles and R. B. Partridge, “Upper Limit on the Mean Mass Density Due to Galaxies,” Astrophysical Journal 148 (1967): 713. 29. J. P. Ostriker and P. J. E. Peebles, “A Numerical Study of the Stability of Flattened Galaxies: Or, Can Cold Galaxies Survive?” Astrophysical Journal 186 (1973): 467–480. 30. J. P. Ostriker, P. J. E. Peebles, and A. Yahil, “The Size and Mass of Galaxies, and the Mass of the Universe,” Astrophysical Journal 193 (1974): L1–­L 4. 31. Jaco de Swart, “Closing in on the Cosmos: Cosmology’s Rebirth and the Rise of the Dark ­Matter Prob­lem,” unpublished manuscript, March 11, 2019, arXiv:1903.05281. 32. Jeremiah Ostriker and Simon Mitton, Heart of Darkness: Unravelling the Mysteries of the Invisible Universe (Prince­ton: Prince­ton University Press, 2013), 193. 33. Jaan Einasto, Ants Kaasik, and Enn Saar, “Dynamic Evidence on Massive Coronas of Galaxies,” Nature 250, no. 5464 (1974): 309–310. 34. Vera Rubin, two-­page manuscript ­table headed “Obs at KPNO & CTIO,” undated, box 169, folder 9, Vera Rubin Papers. 35. Vera C. Rubin, W. Kent Ford Jr., and Norbert Thonnard, “Extended Rotation Curves of High-­Luminosity Galaxies IV. Systematic Dynamical Properties Sa–­Sc,” Astrophysical Journal 225 (1978): L107–­L111. 36. Ken Crosswell, The Universe at Midnight: Observations Illuminating the Cosmos (New York: Simon and Schuster, 2002), 100. 37. Albert Bosma, “The Distribution and Kinematics of Neutral Hydrogen in Spiral Galaxies of Vari­ous Morphological Types” (PhD diss., University of Groningen, 1978). 38. A. Bosma, “21-cm Line Studies of Spiral Galaxies. I. Observations of the Galaxies NGC 5033, 3198, 5055, 2841, and 7331,” Astronomical Journal 86 (1981): 1791–1824.

N O T E S T O PA GE S 1 8 7 – 1 9 3 

285

39. A. Bosma, “21-cm Line Studies of Spiral Galaxies. II. The Distribution and Kinematics of Neutral Hydrogen in Spiral Galaxies of Vari­ous Morphological Types,” Astronomical Journal 86 (1981): 1825–1846. 40. E. Noordermeer, J. M. van der Hulst, R. Sancisi, R. S. Swaters, and T. S. van Albada, “The Mass Distribution in Early-­Type Disc Galaxies: Declining Rotation Curves and Correlations with Optical Properties,” Monthly Notices of the Royal Astronomical Society 376 (2007): 1513–1546. 4 1. Vera C. Rubin, “Rotation Curves of High-­Luminosity Spiral Galaxies and the Rotation Curve of Our Galaxy,” in The Large-­Scale Characteristics of the Galaxy, ed. W. Butler Burton, IAU Symposium 84, College Park, MD, 1978 (Boston: D. Reidel, 1979). 4 2. Vera C. Rubin, W. Kent Ford Jr., and Norbert Thonnard, “Rotational Properties of 21 Sc Galaxies with a Large Range of Luminosities and Radii, from NGC 4605 (4 kpc) to UGC 2885 (122 kpc),” Astrophysical Journal 238 (1980): 471–487. 43. Citation data accessed March 7, 2020. Web of Science Core Collection. © Clarivate (2020). 4 4. David Burstein, Vera C. Rubin, Norbert Thonnard, and W. Kent Ford Jr., “The Distribution of Mass in Sc Galaxies,” Astrophysical Journal 253 (1982): 70–85. 45. S. M. Faber and J. S. Gallagher, “Masses and Mass-­to-­Light Ratios of Galaxies,” Annual Review of Astronomy and Astrophysics 17 (1979): 135–187. 46. Vera C. Rubin, W. Kent Ford Jr., Norbert Thonnard, and David Burstein, “Rotational Properties of 23 Sb Galaxies,” Astrophysical Journal 261 (1982): 439–456. 47. Vera C. Rubin, David Burstein, W. Kent Ford Jr., and Norbert Thonnard, “Rotation Velocities of 16 Sa Galaxies and a Comparison of Sa, Sb and Sc Rotation Properties,” Astrophysical Journal 289 (1985): 81–104. 48. “Interview of Vera Rubin part One,” by Eames Demetrios, February 24, 1995, box 116, folder 11, Vera Rubin Papers. 49. William L. Vanderburgh, “Putting a New Spin on Galaxies: Horace W. Babcock, the Andromeda Nebula and the Dark ­Matter Revolution,” Journal for the History of Astronomy 45 (2014): 141–159. 1 0 . T H E DY N A M I C U N I V E R S E

1. “Department of Terrestrial Magnetism,” in Car­ne­gie Institution of Washington Year Book 71 (1971–1972), 219–221. 2. G. Lemaître, “Un univers homogène de masse constante et de rayon croissant rendant compte de la vitesse radiale des nébuleuses extra-­galactiques,” Annales des Sociétés Scientifiques de Bruxelles 47 (1927): 49–56.

286

N O T E S T O PA GE S 1 9 4 – 1 9 8

3. Edwin Hubble, “A Relation between Distance and Radial Velocity among Extra-­Galactic Nebulae,” Proceedings of the National Acad­emy of Sciences of the United States of Amer­i­ca 15 (1929): 168–173. 4. Georges Lemaître, L’ hypothèse de l’atome primitive (Neuchatel: Editions du Griffon, 1946). 5. G. Gamow, “Expanding Universe and the Origin of Ele­ments,” Physical Review 70 (1946): 572–573. 6. Vera Cooper Rubin, “Fluctuations in the Space Distribution of the Galaxies,” Proceedings of the National Acad­emy of Sciences 40, no. 7 (1954): 541–549. 7. Gérard de Vaucouleurs, “Further Evidence for a Local Super-­Cluster of Galaxies: Rotation and Expansion,” Astronomical Journal 63 (1958): 253–265. 8. R. B. Partridge and David T. Wilkinson, “Isotropy and Homogeneity of the Universe from Mea­sure­ments of the Cosmic Micro­wave Background,” Physical Review Letters 18 (1967): 557–559. 9. E. K. Conklin, “Velocity of the Earth with Re­spect to the Cosmic Background Radiation,” Nature 222, no. 5197 (June 7, 1969): 971–972. 10. Gérard de Vaucouleurs and William L. Peters, “Motion of the Sun with Re­spect to the Galaxies and the Kinematics of the Local Supercluster,” Nature 220 (November 30, 1968): 868–874. 11. Paul S. Henry, “Isotropy of the 3K Background,” Nature 231 (June 25, 1971): 516–518. 12. de Vaucouleurs and Peters, “Motion of the Sun.” 13. “Department of Terrestrial Magnetism,” in Car­ne­gie Institution Year Book 71, 219–221. 14. Vera C. Rubin, W. Kent Ford Jr., and Judith F. Rubin, “A Curious Distribution of Radial Velocities of ScI Galaxies with 14.0 ≤ m ≤ 15.0,” Astrophysical Journal 183 (1973): L111–­L115. 15. Vera C. Rubin, W. Kent Ford Jr., Norbert Thonnard, Morton S. Roberts, and John A. Graham, “Motion of the Galaxy and the Local Group Determined from the Velocity Anisotropy of Distant ScI Galaxies. I. The Data,” Astrophysical Journal 81 (1976): 687–718. 16. Vera C. Rubin, W. Kent Ford Jr., Norbert Thonnard, and Morton S. Roberts, “Motion of the Galaxy and the Local Group Determined from the Velocity Anisotropy of Distant ScI Galaxies. II. The Analy­sis for the Motion,” Astrophysical Journal 81 (1976): 719–737. 17. S. Michael Fall and Bernard J. H. Jones, “Isotropic Cosmic Expansion and the Rubin-­Ford Effect,” Nature 262 (1976): 457–460. 18. M. Clutton-­Brock and P. J. E. Peebles, “Galaxy Clustering and the Rubin-­ Ford Effect,” Astronomical Journal 86 (1981): 1115–1119. 19. Alan Dressler, Donald Lynden-­Bell, David Burstein, Roger L. Davies, Sandra Faber, Roberto J. Terlevich, and Gary Wegner, “Spectroscopy and

N O T E S T O PA GE S 1 9 8 – 2 0 3 

287

Photometry of Elliptical Galaxies. I. A New Distance Estimator,” Astrophysical Journal 313 (1987): 42–58. 20. D. Lynden-­Bell, S. M. Faber, David Burstein, Roger L. Davies, Alan Dressler, R. J. Terlevich, and Gary Wegner, “Spectroscopy and Photometry of Elliptical Galaxies. V. Galaxy Streaming t­ oward the new Supergalactic Center,” Astrophysical Journal 326 (1988): 19–49. 21. P.  A. James, R. D. Joseph, and C. A. Collins, “Se­lection Bias and the Rubin-­Ford Effect,” Monthly Notices of the Royal Astronomical Society 248 (1991): 444–450. 22. Sandra Faber, “Vera Rubin’s Contributions to Astronomy,” Scientific American Guest Blog, December 29, 2016, https://­blogs​.­scientificamerican​ .­com​/­guest​-­blog​/­vera​-­rubins​-­contributions​-­to​-­a stronomy​/­. 23. David Burstein, Vera C. Rubin, Kent Ford Jr., and Bradley C. Whitmore, “Is the Distribution of Mass within Spiral Galaxies a Function of Galaxy Environment?” Astrophysical Journal 305 (1986): L11–­L14. 2 4. Vera C. Rubin, Bradley C. Whitmore, and W. Kent Ford Jr., “Rotation Curves for Spiral Galaxies in Clusters. I. Data, Global Properties, and a Comparison with Field Galaxies,” Astrophysical Journal 333 (1988): 522–541. 25. Burstein, Rubin, Ford, and Whitmore, “Is the Distribution of Mass.” 26. Rubin, Whitmore, and Ford, “Rotation Curves for Spiral Galaxies in Clusters. I.” 27. Bradley C. Whitmore, Duncan A. Forbes, and Vera C. Rubin, “Rotation Curves for Spiral Galaxies in Clusters. II. Variations as a Function of Cluster Position,” Astrophysical Journal 333 (1988): 542–560. 28. Paul Hickson, “Systematic Properties of Compact Groups of Galaxies,” Astrophysical Journal 255 (1982): 382–391. 29. Vera C. Rubin, Deidre A. Hunter, and W. Kent Ford Jr., “One Galaxy from Several: The Hickson Compact Group H31,” Astrophysical Journal 365 (1990): 86–92. 30. Vera C. Rubin, Deidre A. Hunter, and W. Kent Ford Jr., “Optical Properties and Dynamics of Galaxies in the Hickson Compact Groups,” Astrophysical Journal Supplement Series 76 (1991): 151–183. 31. Vera C. Rubin, Norbert Thonnard, and W. Kent Ford Jr., “Observations of NGC 6764, a Barred Seyfert Galaxy,” Astrophysical Journal 199 (1975): 31–38. 32. W. L. W. Sargent, Peter J. Young, A. Boksenberg, Keith Shortridge, C. R. Lynds, and F. D. A. Hartwick, “Dynamical Evidence for a Central Mass Concentration in the Galaxy M87,” Astrophysical Journal 221 (1978): 731–744. 33. Vera C. Rubin, “NGC 5506: An X-­ray Seyfert Galaxy,” Astrophysical Journal 224 (1978): L55–­L57.

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N O T E S T O PA GE S 2 0 3 – 2 0 7

34. Vera C. Rubin, W. Kent Ford Jr., and Charles J. Peterson, “Evidence for Contraction in the Nuclear Ring of the Barred Spiral Galaxy NGC 3351,” Astrophysical Journal 199 (1975): 39–48. 35. Charles J. Peterson, Vera C. Rubin, W. Kent Ford Jr., and Norbert Thonnard, “Motions of the Stars and the Excited Gas in the Barred Spiral Galaxy NGC 3351,” Astrophysical Journal 208 (1976): 662–672. 36. Douglas A. Swartz, Mihoko Yukita, Allyn F. Tennant, Roberto Soria, and Kajal K. Ghosh, “Chandra Observations of Circumnuclear Star Formation in NGC 3351,” Astrophysical Journal 647 (2006): 1030–1039. 37. Charles J. Peterson, Vera C. Rubin, W. Kent Ford Jr., and Norbert Thonnard, “The Velocity Field of the Barred Spiral Galaxy NGC 3351,” Astrophysical Journal 219 (1978): 31–45. 38. Vera C. Rubin, “Velocities and Mass Distribution in the Barred Spiral NGC 5728,” Astrophysical Journal 238 (1980): 808–817. 39. L. Mestel, “On the Galactic Law of Rotation,” Monthly Notices of the Royal Astronomical Society 126 (1963): 553–575. 40. James E. Gunn, Michael Carr, G. Edward Danielson, et al., “Four-­Shooter: A Large Format Charge-­Coupled-­Device Camera for the Hale Telescope,” Optical Engineering 26 (1987): 779–787. 4 1. Vera C. Rubin, Andrew H. Waterman, and Jeffrey D. P. Kenney, “Kinematic Disturbances in Optical Rotation Curves among 89 Virgo Disk Galaxies,” Astronomical Journal 118 (1999): 236–260. 42. Vera C. Rubin, Jeffrey D. P. Kenney, and Judith S. Young, “Rapidly Rotating Circumnuclear Disks in Virgo Disk Galaxies,” Astronomical Journal 113 (1997): 1250–1278. 43. Rubin, Kenney, and Young, “Rapidly Rotating Circumnuclear Disks,” ­Table 5, “Kinematic circumnuclear disk properties of Virgo galaxies.” 4 4. M. L. Humason, N. U. Mayall, and A. R. Sandage, “Redshifts and Magnitudes of Extragalactic Nebulae,” Astronomical Journal 61 (1956): 98–162. 45. Vera Rubin, interview by Carol A. Mockros, unpublished transcript, October 10, 1992, box 95, folder 8, Vera Rubin Papers. 46. V. C. Rubin, “NGC 4550: A Two-­Way Galaxy,” Mercury 22 (1992): 109–110. 47. D. Lynden-­Bell, “Can ­Spherical Clusters Rotate?” Monthly Notices of the Royal Astronomical Society 120 (1960): 204–213. 48. Vera C. Rubin, J. A. Graham, and Jeffrey D. P. Kenney, “Cospatial Counterrotating Stellar Disks in the Virgo E7 / S0 Galaxy NGC 4550,” Astrophysical Journal 394 (1992): L9–­L12. 49. Rubin, “NGC 4550: A Two-­Way Galaxy.”

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1. Miriam Forman, “Recruitment and Retention of ­Women in Physics Conference Held,” American Physical Society CSWP Gazette 11, no. 1, February 1991. 2. Vera Rubin, Introduction to Part 4, in Rubin, Bright Galaxies, Dark M ­ atters (Woodbury, NY: American Institute of Physics, 1997), 151–152. 3. Vera Rubin, “­Women’s Work,” in Rubin, Bright Galaxies, Dark M ­ atters, 164–165. 4. Vera Rubin, “Opening the Doors,” in Rubin, Bright Galaxies, Dark M ­ atters, 174. 5. Susan Simpkin, “Committee on the Status of ­Women,” in The American Astronomical Society’s First C ­ entury, ed. David DeVorkin (Washington, DC: American Institute of Physics / Springer Verlag, 1999). 6. William C. Kelly to Vera Rubin, July 29, 1964, box 29, folder 7, Vera C. Rubin Papers, Manuscript Division, Library of Congress (hereafter Vera Rubin Papers). 7. Elizabeth A. Wood, “Rewarding ­Careers for W ­ omen in Physics,” American Institute of Physics, 1964, box 29, folder 7, Vera Rubin Papers. 8. Vera Rubin to Editor of Nature (John Maddox), September 4, 1970, box 59, folder 2, Vera Rubin Papers. 9. John Maddox to Vera Rubin, September 9, 1970, box 59, folder 2, Vera Rubin Papers. 10. Secretary of the AAS (Laurence W. Fredrick), Notice to Members of the AAS, August 27, 1971, box 64, folder 5, Vera Rubin Papers. 11. Roberta M. Humphreys, “How We Got from Then (1971) to Now—­The Annie Jump Cannon Award and the First Working Group on the Status of ­Women in Astronomy,” oral pre­sen­ta­tion at CSWA Special Session at the 231st Meeting of the AAS, Washington, DC, January 11, 2018. Slides accessed August 24, 2020, at https://­aas​.­org​/­sites​/­default​/­files​/­2019​-­09​/­AJC01​.­02​.­pptx​.­pdf. 12. Secretary of the AAS, Notice to Members, August 27, 1971. 13. Vera Rubin to Bart J. Bok, September 28, 1971, box 64, folder 5, Vera Rubin Papers. 14. Vera Rubin to AAS Special Committee on Cannon Prize, September 27, 1971, box 64, folder 5, Vera Rubin Papers. 15. Vera Rubin to Donald Osterbrock, August 7, 1972, box 64, folder 5, Vera Rubin Papers. 16. Humphreys, “How We Got from Then (1971) to Now.” 17. Vera Rubin to Donald Osterbrock, August 7, 1972. 18. A. Cowley, R. Humphreys, B. Lynds, and V. Rubin, “Report to the Council of the AAS from the Working Group on the Status of ­Women in

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Astronomy—1973,” Bulletin of the American Astronomical Society 6 (1974): 412–423. 19. “About the Cosmos Club,” Cosmos Club, Washington, DC, http://­w ww​ .­cosmosclub​.­org. 20. Vera Rubin to Philip H. Abelson, May 22, 1972, box 64, folder 5, Vera Rubin Papers. 21. Frederic L. Kirgis, The American Society of International Law’s First C ­ entury 1906–2006 (Leiden: Martinus Nijhoff, 2006). 22. Vera Rubin to Elizabeth Ostaggi, Office Man­ag­er of the PSW, September 19, 1972, Department of Terrestrial Magnetism Archives, General Files, Series 2: Rubin, Vera C.—­Biographical (3 boxes), Car­ne­gie Institution of Science, Washington, DC (hereafter DTM Archives). 23. Dirse Sallet, Chair of the PSW Program Committee, to Vera Rubin, Oc­ to­ber 25, 1972, box 30, folder 5, Vera Rubin Papers. 24. Vera Rubin to John Teem, May 31, 1981, box 32, folder 1, Vera Rubin Papers. 25. Richard C. Henry to John Teem, June 10, 1981, box 32, folder 1, Vera Rubin Papers. 26. Margaret Burbidge to Vera Rubin, July 8, 1981, box 32, folder 1, Vera Rubin Papers. 27. Benjamin Weiser, “Proposal to Admit ­Women Is Agitating Cosmos Club,” Washington Post, November 15, 1980. 28. M. H. Liller, A. P. Cowley, P. W. Hodge, F. J. Kerr, and N. D. Morrison, “Report of the Committee on the Status of ­Women,” Bulletin of the American Astronomical Society 12 (1980): 624–635. 29. Committee on the Status of ­Women in Astronomy, “Membership of the CSWA—­Chronological,” https://­aas​.­org​/­comms​/­cswa​/­membership 30. Vera Rubin, “Sexism in Science,” Physics ­Today 31, no. 1 (1978): 13–14; Vera Rubin to “Letters to the Editor, Physics ­Today,” typewritten draft, August 18, 1977, DTM Archives. 31. The Letter cited in Note 30 indicates that the magazine concerned was an issue of Smithsonian published in 1977. 32. Vera Rubin is h ­ ere referring to the Board of Directors of AURA, of which she was a member 1973–1976. 33. Vera Rubin to Ray L. Bowers, September 12, 1979, and enclosure of annotated copy of pages of the CIW Cata­logue 1978–1979, DTM Archives. 34. Vera Rubin to Bryce Crawford Jr, Home Secretary, NAS, April 7, 1986, box 175, folder 1, Vera Rubin Papers. 35. ­Virginia Trimble “Astrophysics in 1991,” Publications of the Astronomical Society of the Pacific 104 (1992): 1–14.

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36. Vera Rubin to Julie Lutz, October 5, 1993, annotation in Rubin’s handwriting that the original (to Howard Bond) was sent on February 13, 1992, box 175, folder 2, Vera Rubin Papers. 37. ­Virginia Trimble to Vera Rubin, February 21, 1992, box 175, folder 2, Vera Rubin Papers. 38. Bruce Carney to Vera Rubin, February 26, 1992, box 175, folder 2, Vera Rubin Papers. 39. Vera Rubin, manuscript of letter to the Editor, New Yorker, July 1, 1982, box 32, folder 7, Vera Rubin Papers. 40. “History of the Equal Rights Amendment,” Alice Paul Institute, Mt. Laurel, NJ, 2018, https://­w ww​.­equalrightsamendment​.­org ​/­t he​- ­equal​-­rights​ -­a mendment. 4 1. E. Margaret Burbidge, interview by David DeVorkin, July 13, 1978, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­aip​.­org​/­history​-­programs​/­niels​-­bohr​-­library​ /­oral​-­histories​/­25487. 42. Vera Rubin to M. Joan Callanan, May 5, 1982, box 32, folder 7, Vera Rubin Papers. 43. National Science Foundation, ­Women and Minorities in Science and Engineering, January 1982, i. 4 4. Derek McNally to Michael Penston (representing the Royal Astronomical Society’s Committee on the Status of ­Women in British Astronomy and Geophysics), January 2, 1990, enclosed with an undated note from Michael Penston to Vera Rubin, box 159, folder 11, Vera Rubin Papers. 45. Jean-­Pierre Swings, IAU General Secretary, to Deidre Hunter, October 5, 1987, box 111, folder 6, Vera Rubin Papers. 46. Deidre A. Hunter and Vera C. Rubin, “­Women Worldwide in Astronomy,” Mercury 21, (1992): 32–34. 47. D. Hunter, V. Abalakin, E. Athanassoula, J. Bergeron et al., “­Women Worldwide in Astronomy,” undated manuscript, box 111, folder 6, Vera Rubin Papers. 48. Anne Cowley to Vera Rubin, memo headed “­Women at International Meetings,” July 12, 1990, box 159, folder 11, Vera Rubin Papers. 49. Kenneth Kellerman to the AAS Council, memo, copied to Vera Rubin, undated (c. 1992–1993), box 111, folder 6, Vera Rubin Papers. 50. C. M. Urry, L. Danly, E. J. Schreier, and S. Tobias, “The Baltimore Charter for W ­ omen in Astronomy,” 1992, http://­w ww​.­stsci​.­edu​/­stsci​/­meetings​/ ­WiA​ /­BaltoCharter​.­html. 51. The National Acad­emy of Sciences is now part of the National Academies of Sciences, Engineering, and Medicine.

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52. Vera Rubin to Frank D. Drake, November 9, 1989, box 75, folder 6, Vera Rubin Papers. 53. Marian Glenn, Association of ­Women in Science Newsletter 18, no. 6 (1989): 14. 54. Vera Rubin to William Spindel, November 13, 1989, box 75, folder 6, Vera Rubin Papers. 55. Vera Rubin to Frank Press, November 16, 1990, box 75, folder 6, Vera Rubin Papers. 56. Sandra Faber to Frank Press, February 14, 1991, box 111, folder 7, Vera Rubin Papers. 57. Frank Press to Karen K. Uhlenbeck, December 19, 1990, box 111, folder 7, Vera Rubin Papers. 58. Vera Rubin to Mildred S. Dresselhaus, July 29, 1992, box 111, folder 8, Vera Rubin Papers. 59. Sheila David to Vera Rubin, April 29, 1993, box 75, folder 6, Vera Rubin Papers. 60. Vera Rubin to Bruce Alberts and ­others, December 27, 1999, box 176, folder 1, Vera Rubin Papers. 61. Beyond Bias and Barriers: Fulfilling the Potential of ­Women in Academic Science and Engineering (Washington DC: National Academies Press, 2007). 62. Jaleh Daie, President of AWIS, to Vera Rubin, January 10, 1995, box 111, folder 10, Vera Rubin Papers. 63. Vera Rubin, interview by Carol A. Mockros, unpublished transcript, October 10, 1992, box 95, folder 8, Vera Rubin Papers. 64. Wendy Freedman to Vera Rubin, June 10, 1986, box 175, folder 1, Vera Rubin Papers. 1 2 . WO N D E R F U L L I F E

1. Vera Rubin, “An In­ter­est­ing Voyage,” Annual Review of Astronomy and Astrophysics 49 (2011): 1–28, 15–16. 2. Alycia Weinberger, “Remembering Vera,” in the “Memories” section, Earth and Planets Laboratory, Car­ne­gie Science, https://­dtm​.­carnegiescience​.­edu​ /­remembering​-­vera. 3. Jocelyn Bell Burnell, diary entry, May 8, 2000, private communication to authors. 4. Vera Rubin, interview by Carol A. Mockros, October 10, 1992, unpublished transcript, box 95, folder 8, Vera C. Rubin Papers, Manuscript Division, Library of Congress (hereafter Vera Rubin Papers). 5. Vera Rubin to Merle Tuve, April 6, 1981, box 32, folder 5, Vera Rubin Papers. 6. Vera Rubin, interview by Carol A. Mockros.

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7. Alicia Aarnio, in “Remembering Vera,” in the “Memories” section, Earth and Planets Laboratory, Car­ne­gie Science, https://­dtm​.­carnegiescience​.­edu​ /­remembering​-­vera. 8. Vera Rubin to Margaret Burbidge, September 13, 1984, box 98, folder 3, Vera Rubin Papers. 9. Rubin, “An In­ter­est­ing Voyage,” 19–20. The mention ­here of the First Vatican Observatory Summer School in the summer of 1985 is incorrect. It took place in 1986. 10. Vera Rubin to Frances D. Fergusson, October 21, 1986, box 100, folder 2, Vera Rubin Papers. 11. Vera Rubin to Frances D. Fergusson, February 27, 1987, box 100, folder 2, Vera Rubin Papers. 12. Frances D. Fergusson to Vera Rubin, February 18, 1987, box 100, folder 2, Vera Rubin Papers. 13. Rubin, “An In­ter­est­ing Voyage,” 17. 14. Vari­ous correspondence, box 126, folder 11, Vera Rubin Papers. 15. Vera Rubin to Yuval Ne’eman, January 5, 1971, box 195, folder 12, Vera Rubin Papers. 16. Janet Land, “Vera Rubin: One of the DTM’s Star Scientists,” Car­ne­gie Institution Newsletter, November 1974. 17. Vera Rubin, “Preface,” in Rubin, Bright Galaxies, Dark M ­ atters (Woodbury, NY: American Institute of Physics, 1997), xiv. 18. Vera Rubin, “Lifelines,” Nature 425 (October 23, 2003): 773. 19. Weinberger, in “Remembering Vera.” 20. Vari­ous documents, 1997, box 78, folder 9, Vera Rubin Papers. 21. Rubin, “An In­ter­est­ing Voyage,” 23. 22. Vera C. Rubin, W. Kent Ford Jr., and Norbert Thonnard, “Extended Rotation Curves of High-­Luminosity Galaxies IV. Systematic Dynamical Properties Sa–­Sc,” Astrophysical Journal 225 (1978): L107–­L111. 23. Vera C. Rubin, W. Kent Ford Jr., and Norbert Thonnard, “Rotational Properties of 21 Sc Galaxies with a Large Range of Luminosities and Radii, from NGC 4605 (4 kpc) to UGC 2885 (122 kpc),” Astrophysical Journal 238 (1980): 471–487. 2 4. Vera C. Rubin, David Burstein, W. Kent Ford Jr., and Norbert Thonnard, “Rotation Velocities of 16 Sa Galaxies and a Comparison of Sa, Sb, and Sc Rotation Properties,” Astrophysical Journal 289 (February 1, 1985): 81–104. 25. John H. Gibbons to Vera Rubin, July 13, 1993, box 114, folder 4, Vera Rubin Papers. 26. CV submitted in support of Vera Rubin’s nomination for the National Medal of Science, box 114, folder 4, Vera Rubin Papers.

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27. National Science Foundation Fact Sheet on the National Medal of Science, 1983, box 114, folder 4, Vera Rubin Papers. 28. Vari­ous documents, 1993, box 114, folder 4, Vera Rubin Papers. 29. Vera Rubin to Carole Jordan, February 27, 1996, box 82, folder 6, Vera Rubin Papers. 30. “President Clinton Names Five New Members to the National Science Board,” White House press notice, July 26, 1996, box 76, folder 1, Vera Rubin Papers. 31. National Science Foundation, “About the NSB,” https://­w ww​.­nsf​.­gov​/­nsb​ /­about​/­index​.­jsp. 32. Marta Cehelsky, NSB Executive Officer, to Vera Rubin, July 26, 1996, box 76, folder 1, Vera Rubin Papers. 33. Vera Rubin to Marta Cehelsky, December 13, 1966, box 76, folder 4, Vera Rubin Papers. 34. Vera Rubin’s CV, unpublished, 2009. Courtesy Department of Terrestrial Magnetism (DTM), Car­ne­gie Institution for Science, Washington, DC. 35. Vera Rubin, “An In­ter­est­ing Voyage,” 22. 36. Vera Rubin, interview with Carl Lankowski and Pam Lankowski, Historic Chevy Chase DC, November 5, 2011, https://­w ww​.­historicchevychasedc​.­org​ /­oral​-­histories​/­vera​-­rubin​/­. 37. Vari­ous documents, box 134, folder 2, Vera Rubin Papers. 38. Vari­ous documents, box 141, folder 6, Vera Rubin Papers. 39. Vera Rubin to Rev. Timothy S. Healy SJ, December 24, 1982, box 32, folder 8, Vera Rubin Papers. 40. Martin McCarthy, “Report by MFM on Consultation with V. C. Rubin Washington DC 5 June 83 on the Tucson Castel Gandolfo Experiment of the Vat. Obs.,” box 103, folder 1, Vera Rubin Papers. The typewritten note is annotated by hand “Notes by MFM. To be submitted for review to VCR.” 4 1. Martin McCarthy to Vera Rubin, July 20, 1986, box 103, folder 1, Vera Rubin Papers. 42. Martin McCarthy to Sandro D’Odorico, July 23, 1986, box 103, folder 1, Vera Rubin Papers. 43. Vera Rubin, “Reminiscences of the First Vatican Summer School,” unpublished manuscript, 1996, box 81, folder 10, Vera Rubin Papers. 4 4. Vera Rubin to Sandra Faber, Donald Lynden-Bell, and Alex Szalay, February 27, 1987, box 209, folder 3, Vera Rubin Papers. 45. Rubin, “Lifelines.” 46. Vera Rubin, interview by Carol A. Mockros. 47. Deidre A. Hunter, Vera C. Rubin, Rob A. Swaters, Linda S. Sparke, and Stephen E. Levine, “The Stellar Velocity Dispersion in the Inner 1.3 Disk Scale Lengths of the Irregular Galaxy NGC 4449,” Astrophysical Journal 634, no. 1 (2005): 281–286.

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4 8. Deidre A. Hunter, “Vera Cooper Rubin (1928–2016),” Publications of the Astronomical Society of the Pacific 129, no. 174 (April 2017): 1–4. 49. Vera Rubin to Mildred Dresselhaus and Susan Solomon, April 12, 2002, box 171, folder 2, Vera Rubin Papers. 50. Judith Young, after-­dinner address, typescript, June 2009. Courtesy Rubin ­family. 51. Barbara Spector, “A love of science: Do parents pass it along to their c­ hildren?” The Scientist 5, no. 19 (September 30, 1991). 52. Vera Rubin, “Reminiscences 1994: Observing at the National Facilities,” Bright Galaxies, Dark M ­ atters, 88. 53. Vera Rubin, “An Unconventional ­Career,” Bright Galaxies, Dark M ­ atters, 163. 54. Rubin, “An Unconventional ­Career,” 163. 55. Vera Rubin, typewritten note, 1973, Department of Terrestrial Magnetism Archives, General Files, Series 2: Rubin, Vera C.—­Biographical (3 boxes), Car­ne­gie Institution of Science, Washington, DC. 56. Ruth Burg, Eulogy delivered at funeral of Vera Rubin, 2016. Courtesy of Ruth Burg. 57. David DeVorkin, “Capturing the Essence of Astronomer Vera Rubin,” National Air and Space Museum, Smithsonian, December 30, 2016, https://­ airandspace​.­si​.­edu​/­stories​/­editorial​/­capturing​-­essence​-­astronomer​-­vera​-­rubin. 58. Neta A. Bahcall, “Vera Rubin (1928–2016),” Nature 542 (February 2, 2017): 32; Matt Schudel, “Vera Rubin, Astronomer Who Proved Existence of Dark ­Matter, Dies at 88,” Washington Post, December 26, 2016; Howard Blume, “Pioneering Astronomer Vera Rubin Dies at 88; She Helped Find Evidence of Dark ­Matter,” Los Angeles Times, December 26, 2016. 59. Dennis Overbye, “Vera Rubin, Scientist Who Opened Doors for Physics and for ­Women, Dies at 88,” New York Times, December 28, 2016, A18. 60. Sandra Faber, “Vera Rubin’s Contributions to Astronomy,” Scientific American Guest Blog, December 29, 2016, https://­blogs​.­scientificamerican​ .­com​/­guest​-­blog​/­vera​-­rubins​-­contributions​-­to​-­a stronomy​/­. 61. Vera Rubin, interview by Carol A. Mockros. 62. Lisa Randall, “Why Vera Rubin Deserved a Nobel,” New York Times, January 4, 2017, A21. 63. Vera Rubin, interview by David DeVorkin and Ashley Yeager, July 20, 2007, Oral Histories, Niels Bohr Library and Archives, American Institute of Physics, College Park, MD, https://­w ww​.­a ip​.­org​/­history​-­programs​/­niels​ -­bohr​-­library​/­oral​-­histories​/­4 4082. 64. Robert Irion, “The Bright Face ­behind the Dark Sides of Galaxies,” Science 295, no. 5557 (February 8, 2002): 960–961. 65. American Physical Society, “Car­ne­gie Institution, Department of Terrestrial Magnetism,” November 8, 2013, https://­w ww​.­aps​.­org​/­programs​/­outreach​ /­history​/­historicsites​/­carnegie​.­cfm.

Acknowl­edgments

When the opportunity arose for us to write a biography of Vera Rubin, the task seemed both daunting and irresistible. Would we find enough material to make the story in­ter­est­ing? How could we best do justice to her—­one of the most outstanding astronomers of her generation—as a scientist and a person? And yet one of us (Jacqueline Mitton) had for many years been giving talks to amateur astronomers, community groups, and cruise passengers ­under the title “A ­Woman’s Place is in the Dome”— ­a slogan Jacqueline did not invent but was more than happy to adopt. Vera Rubin certainly made herself thoroughly at home in observatory domes, freely admitting that she never felt happier than when she was observing. And one of us (Simon Mitton) had already experienced the satisfaction of researching and writing about the life of an eminent astronomer—­Fred Hoyle. We w ­ ere in no doubt we wanted to take on the challenge together. So began a three-­year journey alongside Vera, beginning with her f­amily history and earliest childhood, through school, college, marriage and ­family, and her anxiety about w ­ hether she would ever make it as an astronomer, to the climax of her c­ areer and her national and international recognition. Our journey took us to Washington, DC, to see for ourselves where she studied and worked at Georgetown University and at the Department of Terrestrial Magnetism of the Car­ne­gie Institution for Science. We searched archives and talked to p ­ eople who had known her. The more we have learned, the more we have come to admire her remarkable achievements in science and the ways her warmth of personality and care for ­others touched so many. As for our concern about w ­ hether t­ here would be enough in­ter­est­ing material to fill a book, we need not have worried. In the event, our prob­lem has been what to leave out rather than what to include. Vera recorded oral histories, gave numerous interviews, and wrote an autobiographical memoir, in which she spoke of her professional c­ areer and ­family life. Most of ­these are in the public domain. They are valuable resources for biographers and give a perspective on how Vera viewed ­things with hindsight. But our greatest insight into the real­ity of her life, why and how she made decisions, and what she was feeling, came from the remarkable collection

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of her personal papers held in the Library of Congress. Fortunately, Vera seems to have filed almost e­ very letter that landed on her desk and copies of many that she sent, along with all her research files and assorted miscellaneous paperwork dating back to her student days. ­These con­temporary documents ­really bring Vera’s character to life. They also show that, in ­later years, her memories had sometimes faded, and that t­ here ­were aspects of her life she rarely, if ever, mentioned to interviewers. Vera had not looked through most of her older files for de­cades when she donated them to the Library of Congress. No one had. We w ­ ere lucky to be the first to have that privilege.

We are indebted to the many p ­ eople and organ­izations who have helped us or given us permission to use copyrighted material. The support and encouragement of Vera Rubin’s ­family has been especially impor­tant. We would particularly like to thank Allan Rubin, who has acted as our point of contact with the ­family throughout and shared relevant documents and photo­graphs still in the f­ amily’s possession. He and Karl both made helpful comments on a draft of our manuscript. Allan, David, and Karl told us about the oral history recorded by their grand­father, and made it available to us. We are grateful to them all for permission to quote from this recording and from Vera’s papers in the Library of Congress collection, and to reproduce photo­graphs from the ­family collection. We have also much appreciated the assistance of Vera’s s­ ister, Ruth Burg, who spared the time for a long telephone call and provided vari­ous documents—­and a copy of Bob and Vera’s wedding photo­graph. When we began our research in 2018, we discovered that Rubin’s papers in the Library of Congress ­were only just being pro­cessed and w ­ ere not yet available to the public. We are eternally grateful for the flexibility the library showed and in par­tic­u­lar for the wonderful help we received from archivist Karen Linn Femia, who allowed us early access to the collection while she was still pro­cessing it. At the Department of Terrestrial Magnetism (since 2020 part of the Earth and Planets Laboratory), librarian and archivist Shaun Hardy helped us with our research ­there and with the scanning of images. Janice Dunlap also helped with some of the images. We thank them both personally, and also the Car­ne­gie Institution of Washington for permission to quote from documents in the DTM archives and to reproduce images held in the Vera C. Rubin Photo­graph Collection (1942–2012). In figure captions we have used the abbreviated form “DTM, Car­ne­gie Institution of Washington” to acknowledge that permission. The wonderful oral history transcripts made available online by the Neils Bohr Library and Archive of the American Institute of Physics w ­ ere an invaluable resource and we are grateful for permission to quote from them. We also wish to acknowledge the American Astronomical Society for permission to reproduce diagrams from The Astrophysical Journal.

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The following p ­ eople all gave us valuable assistance: Laura Caron of Georgetown University Astronomical Society; Lynn Conway, university archivist at Georgetown University; David DeVorkin of the Smithsonian Air and Space Museum; Chunyang Ding of Yale Scientific Magazine; Eisha Neely of the Carl A. Kroch Library at Cornell University; and Dean M. Rogers of Vassar College Libraries. Peter Teuben kindly gave us permission to reproduce his photo­graph of Vera Rubin with her ­daughter, Judy Young (Fig. 12.5). We thank them all, and also the many colleagues with whom we have had in­ter­e st­ing and helpful discussions about their memories of Vera Rubin, including Jocelyn Bell Burnell, Peter Boyce, George Coyne, Debra Elmegreen, Steve Maran, Jeremiah Ostriker, and Alycia Weinberger. Sandra Faber and Morton Roberts provided very useful and constructive suggestions for improving the chapters concerned with Rubin’s work on galaxy rotation curves. We apologize if we have neglected to acknowledge anyone we should have named. Last but not least, we would like to thank the team at Harvard University Press, especially our editor Janice Audet, whose editorial comments, wise advice, and unstinting support helped us make this a better book.

Index

Aarnio, Alicia, 4 Abelson, Philip H. (1913–2004), 217 Abt, Helmut A. (b. 1925), 113, 116, 117 Alberts, Bruce, 229 Alpher, Ralph A. (1921–2007), 65, 66–67, 73–74 American Association of Physics Teachers, 208 American Association of University W ­ omen, 70, 215 American Astronomical Society, 60, 86, 227; Annie J. Cannon Award, 212–215; Apollo program questionnaire, 106; Committee on the Status of ­Women in Astronomy, 219–220, 223, 225; Equal Rights Amendment policy, 223; 33rd meeting Washington, DC (1924), 159; 84th meeting, Haverford, Pennsylvania (1950), 57, 58–61, 83, 94; 86th meeting East Cleveland, Ohio (1951), 87; 92nd meeting Prince­ton, New Jersey (1955), 88; 110th meeting Cambridge, Mas­sa­chu­setts (1962), 110; 113th meeting Tucson, Arizona (1963), 116; 121st meeting Hampton, V ­ irginia (1966), 149; 128th meeting Austin, Texas (1968), 167; 235th meeting, Honolulu, Hawaii (2020), 1; Rubin’s Russell Prize Lecture, 156; working group on ­women in astronomy, 215–216, 219 American Institute of Physics, 208, 209, 210 American Physical Society, 208, 222, 251 Andromeda Galaxy: Baade’s observations, 77–78, 150–151; Cepheid variables, 159;

chemical composition, 173, 174; distance, 159, 164; history of observation, 156–161; H II regions, 150, 160, 161, 163, 165, 170; mass, 160, 165, 166, 168–169, 170, 172, 173, 174; mass-­to-­light ratio, 174–175; Milky Way comparison, 55, 152, 159, 169–170, 174; nucleus, 157, 173–174; radial velocity, 158; radio observations, 154–155, 169, 170, 171–172; rotation curve, 108, 154–155, 158–159, 160–161, 165, 167, 168–173, 174, 182; rotation discovery, 158; Rubin and Ford’s 1970 paper, 152, 168–170; Rubin and Ford’s observations, 149, 150–151, 161–164; stellar populations, 77–78 Andromeda Nebula, 17, 156, 157, 158, 159, 168. See also Andromeda Galaxy Antarctica. See South Pole Applebaum, Rose. See Cooper, Rose Applied Physics Laboratory (APL), 63–65, 67, 75, 90 Arp, Halton C. (1927–2013), 151 Association for ­Women in Science, 222, 230–231, 237 Association of Universities for Research in Astronomy (AURA), 219, 227 Astronomical Journal, 60, 61, 111, 112, 176, 244 Astrophysical Journal, 68, 77, 81–82, 86, 116, 140, 151, 183, 200; Rubin’s published papers, 93, 118, 120, 140, 168, 170, 176, 185, 187, 244; Rubin’s rejected papers, 61, 82 Auroral display (1941), 16

302 I n d e x Baade, W. H. Walter (1893–1960), 77–80, 86, 87, 88, 137, 150–151 Babcock, Horace W. (1912–2003), 125, 126, 130, 139, 142, 144–145, 160 Baldwin, John E. (1931–2010), 171 Baltimore Charter, 227 Batchelor, George K. (1920–2000), 79 Bell Burnell, S. Jocelyn (b. 1943), 232 Bell Telephone Com­pany, 9, 10, 16, 210 Bethe, Hans A. (1906–2005), 53, 66–67, 79 Boggess, Nancy (1925–2019), 80, 86 Bok, Bart J. (1906–1983) and Priscilla F. (1896–1975), 213 Bond, Howard, 221–222 Boothroyd, Samuel L. (1874–1965), 51 Bosma, Albert, 186–187 Bowen, Ira S. (1898–1973), 124 Boyce, Peter B. (b. 1936), 140, 147 Bright Galaxies, Dark ­Matters, 103, 147 Brouwer, Dirk (1902–1966), 59, 60, 111 Burbidge, E. Margaret (1919–2020): Annie Jump Cannon award, 212–213, 216; Cosmos Club, 218, 219; discrimination by Car­ne­gie Observatories, 124–125; friendship with de Vaucouleurs, 94; friendship with Rubin, 80, 86, 129, 134, 233; galaxy rotation curve work, 109–110; Gold Medal of Royal Astronomical Society, 144; International Astronomical Union, 225–226; La Jolla, 116, 119, 177; McDonald Observatory, 104, 110, 130, 135–136; National Acad­e my of Sciences, 237; NGC 7469, 138–139; NUFFIC summer course (1960), 102; on Equal Rights Amendment, 223; Rubin’s work with, 116, 120, 131, 135–136, 155, 177–178; Warner Prize, 213 Burbidge, Geoffrey (1925–2010): AAS Council membership, 213; discrimination by Car­ne­g ie Observatories, 124–125; friendship with de Vaucouleurs, 94; friendship with Rubin, 80; galaxy rotation curve work, 109–110; La Jolla, 116, 119, 177; McDonald Observatory,

104, 109, 130, 135; NGC 7469, 138–139; NUFFIC summer course (1960), 102; on dark ­matter, 182; Rubin’s work with, 116, 120, 131, 135–136, 155, 177–178; Warner Prize, 213 Burg, Ruth Cooper, 5, 9–12, 13, 15, 24, 237, 248 Burke, Bernard F. (Bernie) (1928–2018), 130, 131, 154 Burley, Jaylee. See Mead, Jaylee Burley Burroughs E101 computer, 101–102, 103 Burstein, David (1947–2009), 177, 188, 199 Byberry asylum, 12 California Institute of Technology (CalTech), 124, 130, 132, 137, 140, 142, 144, 147, 180 Calvin Coo­lidge High School, 23–26 Campbell, William Wallace (1862–1938), 158 Cannon, Annie J. (1863–1941), 212 Car­ne­gie Institution for Science. See Car­ne­gie Institution of Washington Car­ne­gie Institution of Washington, 2, 129, 130, 132, 204, 217, 220–221, 228. See also Department of Terrestrial Magnetism Car­ne­gie Observatories, 116, 124, 139, 180, 231. See also Mount Wilson and Palomar Observatories; Mount Wilson Observatory; Palomar Observatory Carpenter, Edwin F. (1898–1963), 61 Carpenter, Martha Stahr, 52–53, 54, 56, 57, 58 Cerro Tololo Inter-­A merican Observatory, 147–149, 176, 185, 196, 199 Chandrasekhar, Subrahmanyan (1910–1995), 82–83 Clerke, Agnes Mary (1842–1907), 156 Clinton, Bill, 237, 241 Clinton, Hillary, 241 Coma cluster of galaxies, 180, 181, 182 Cooper, Philip (Pete): birth of ­daughters, 10; cars, 12–13, 15; early life, 6–9; education, 7, 9; employment, 9–10, 11, 12, 13–14, 15; marriage, 10; move to Washington, 13–15; support for Vera, 18, 19, 36, 58–59, 68, 71–72, 75, 79, 101, 243; war­time ser­vice, 16

Index

Cooper, Rose (née Applebaum), 6, 9–15, 26, 27, 42, 46, 79, 99; death, 243; support for Vera, 58–59, 68, 71–72, 79, 101, 243 Cooper, Ruth. See Burg, Ruth Cooper Cornell University: astronomy department, 49, 51–52, 54; Bob Rubin’s studies, 42, 48–49; Fuertes Observatory, 51; physics department, 40, 52, 53–54; radio astronomy, 52; Rubin’s applications, 33, 43, 50; Rubin’s studies, 53–57, 70, 194 Cosmic micro­wave background: anisotropy, 195, 197; as reference frame, 195; discovery by Penzias and Wilson, 195; prediction of, 67 Cosmos Club: award to Rubin, 245; discrimination against w ­ omen, 216–219 Cowley, Anne P. (b. 1938), 213, 215, 226 Coyne, George, SJ (1933–2020), 112–113 Crampin, D. Joan (1936–1990), 119, 120 Dark m ­ atter: assessments of Rubin’s contribution, 1–3, 4, 179, 191–192, 237, 238, 248–250; in compact groups of galaxies, 201; cosmological significance, 182–183, 186; discovery of evidence, 2, 4, 172, 179–188, 191–192, 199, 238, 249; first use of term, 180; in galaxy clusters, 189, 198, 199–200; halos around galaxies, 183, 184, 186, 191, 199; in Milky Way, 184; in stability of galaxies, 183 Davies, Rodney D. (Rod) (1930–2015), 170 Department of Terrestrial Magnetism (DTM): Car­ne­gie image tube, 131–132; collaboration with Vatican Observatory, 141–142; DTM image tube spectrograph, 136, 138, 144–146, 149, 150, 152, 163, 164; history, 129–130; Proximity fuze proj­ect, 64; radio astronomy group, 130, 151, 154, 170; registered as Historic Physics Site, 251; rivalry with Car­ne­gie Observatories, 139, 144–146; Rubin’s employment, 129–131, 133–135, 245; Rubin’s relationship with, 70, 233, 235. See also image tubes de Vaucouleurs, Antoinette (1921–1987), 94

303 de Vaucouleurs, Gérard (1918–1995), 56, 61–62, 94–98, 101, 102, 103–105, 106, 109, 167, 195 DeVorkin, David (b. 1944), 248 DeWitte-­Morette, Cécile (1922–2017), 99 District of Columbia, po­liti­cal repre­sen­ta­tion, 84–85 D’Odorico, Sandro, 235 Drake, Frank D. (b. 1930), 228 Dresselhaus, Mildred S. (1930–2017), 229 DTM. See Department of Terrestrial Magnetism Dwingeloo Radio Observatory, 102, 154 Eastern Colleges Science Conference, 39, 41–43 Eclipse, solar: Rubin’s research, 93; total eclipse in 1963, 118. See also Georgetown University Eddington, Sir Arthur S. (1882–1944), 18 Edmondson, Frank K. (1912–2008), 93, 102 Einasto, Jaan (b. 1929), 184 Emerson, Darrel, 171 Emission nebula, 151, 152, 160, 161. See also H II region Equal Rights Amendment, 223–224 Everett, Edward (1794–1865), 29 Ewen, Harold I. (1922–2015), 87 Faber, Sandra Moore (b. 1944), 143–144, 189, 198, 228, 250 Feurer, Lewis S. (1912–2002), 36–37 Feynman, Richard P. (1918–1988), 40, 42, 52, 53, 54, 57, 58 Ford, W. Kent, Jr. (b. 1931): collaboration with Rubin, 2, 134, 136, 138–141, 147, 149, 151, 155, 158, 161–164, 173, 177, 185–187, 200–202, 232, 237, 249, 251; Committee on the Status of ­Women in Astronomy membership, 220; competitiveness with Car­ne­g ie Observatories, 144–147, 150; development of image tube spectrograph, 131–132, 136, 149, 176; papers with Rubin, 140, 152, 164, 169–171, 174, 182, 186–188, 196, 236; Rubin-­Ford effect, 193, 197–198

304 I n d e x Frank, Philipp (1884–1966), 40 Freedman, Wendy L. (b. 1957), 231 Freeman, Kenneth (b. 1940), 182, 186 Frenkiel, François N. (1910–1986), 75 Furness, Caroline E. (1869–1936), 30 Galaxies: barred spiral, 202, 203; classification, 176; cluster galaxies, 199, 204–205; distance mea­sure­ment, 56, 78; distribution in space, 74, 194; field galaxies, 198–199, 201; formation, 73–74; mass, 110, 183–184, 186–188, 206; massive halos, 184, 186, 187–189, 199; mass-­to-­l ight ratio, 159, 174–175, 178, 181, 182, 183, 186; nature, 156–158; photometry, 98, 103; quasi-­stellar, 138; radial velocities, 56, 196; rotation, 55, 108, 110, 111, 119, 150, 155, 176, 178, 185–186, 188; Sa, 176, 191, 198; Sb, 176, 191, 198; Sc, 176, 191, 196, 198; Seyfert, 138, 202–203; spiral, 152, 176, 191, 198–199. See also Dark ­matter; Rotation curves; Milky Way; individually named galaxies Galaxy, The. See Milky Way Gallagher, John, 189 Gamow, George (1901–1968): collaboration with Alpher, 66–67; defection to the USA, 65; early life, 65–66; galaxy formation theory, 73–74; Michigan symposium, 76, 79–80; origin of the ele­ments, 66, 194; publication of Rubin’s thesis, 81–83; rotating universe theory, 55–56; turbulent universe theory, 83; Vera Rubin connection, 63, 67–68, 70–71, 73–76, 81 Gender-­neutral language, 220–222 Georgetown University: Air Force contracts, 88, 89–91, 93; astronomy department, 68–69, 71, 73, 88–89, 92, 127; astronomy teaching, 71, 91, 101, 121, 122–123; John Glenn’s visit, 114–115; observatory building, 68–69; registration as a student, 70, 74–75; Rubin’s employment, 88–89, 90, 93–94; Rubin’s gradu­ate students, 106–107, 108, 110–112; Rubin’s honorary degree,

243; Rubin’s PhD awarded, 81, 84; Rubin’s resignation, 127, 129, 130–131, 134; Rubins’s donation, 242–243; solar eclipse observing, 89–90 George Washington University, 65, 66 GI Bill, 49 Gingerich, Owen J. (b. 1930), 80–81 Glenn, John H. (1921–2016), 114–115 Gloversville (New York), 7, 8 Goldberg, Leo (1913–1987), 76–77 Gottesman, Stephen T. (b. 1939), 170 ­Great Attractor, 198 Greenstein, Jesse L. (1909–2002), 140 H II region, 151, 160, 161, 163, 165, 170. See also Emission nebula Hagen, John P. (1908–1990), 71 Hall, John S. (1908–1991), 136 Harvard College Observatory, 19, 52, 96 Harvard University, 49–50, 52, 77, 87, 237 ­Hazard, Cyril (b. 1928), 137 Healea, Monica (1899–1993), 50 Heckman, Otto H. L. (1901–1983), 109 Hempel, Carl G. (1905–1997), 40 Henry, Paul, 195 Henry, Richard C. (b. 1940), 219 Herman, Robert (1914–1997), 65, 66, 67 Herschel, Caroline (1750–1848), 156, 241 Herschel, William (1738–1822), 156 Heyden, Francis J., SJ (1907–1991), 69–70, 71, 73, 88–94, 101, 115, 121–123, 124, 141, 242–243 Hickson compact groups (of galaxies), 200–201 Hogg, Helen Sawyer (1905–1993), 213 Hubble, Edwin P. (1889–1953), 17, 18, 116, 159, 176, 180, 181, 191, 193 Hubble expansion. See Hubble flow Hubble flow, 193–194, 196–198 Hubble-­L emaître law, 180 Huggins, William (1824–1910), 156 Humason, Milton L. (1891–1972), 17, 159, 180, 181

Index

Humphreys, Roberta M. (b. 1944), 214, 215 Hunter, Deidre A., 3, 200, 201, 225–226 Image tubes: advantages, 136–137, 138, 140, 141, 150; DTM image tube spectrograph, 136, 138, 144–146, 149, 150, 152, 163, 164; DTM proj­ect, 14, 130, 131, 132, 133, 134, 136; Joint Committee on Image Tubes for Telescopes, 132, 133 International Astronomical Union: General Assembly Rome, Italy (1952), 77, 78; General Assembly Berkeley, California (1961), 109; General Assembly Hamburg, Germany (1964), 123–124; General Assembly Brighton, UK (1970), 171; General Assembly, Baltimore, USA (1988), 225; General Assembly, Buenos Aires (1991), 225; policy on status of ­women, 224–226; Rubin admitted as member, 123; Symposium 15 Santa Barbara, California (1961), 109–110; Symposium 84 (1979), 187; Symposium 148 Sydney, Australia (1990), 226; US National Committee, 226; ­Women Worldwide in Astronomy event (1988), 225 Israel, Rubin’s visit (1984), 234–235 Japan, Rubin’s visit (1978), 234 Jeans, Sir James (1877–1946), 18, 180 Jewish ­people: emigration to the USA, 7–8, 9, 42; persecution, 7, 9 Jodrell Bank, 170 Johns Hopkins University, 63, 64 Jordan, Carole (b. 1941), 240 Kaasik, Ants, 184 Kant, Immanuel (1724–1804), 156 Keeler, James E. (1857–1900), 156–157 Keller, Geoffrey (1918–2007), 93, 101 Kellerman, Kenneth I. (b. 1937), 226 Kelly, William C., 209 Kennedy, John F., 106; assassination, 121–122 Kenney, Jeffrey, 203 Kent, Stephen, 172–173

305 Kepler, Johannes (1571–1630): Keplerian rotation, 108, 111, 154, 167; laws of planetary motion, 108, 166, 167 Kerr, Frank J. (1918–2000), 59 Kiess, Carl, C. (1887–1967), 71, 72–73, 92, 93, 94 Kitt Peak National Observatory (KPNO), 113, 116, 117, 136, 176, 244; Rubin’s grants of observing time, 118, 120, 130, 147, 163, 164, 185, 196, 199, 201, 202, 205, 233 Kobchefski, Pesach. See Cooper, Philip (Pete) La Jolla, California, 117, 118 Large Synoptic Survey Telescope, 1 League of ­Women Voters, 84 Leavitt, Henrietta Swan (1868–1921), 78 Leiden Observatory, 102 Lemaître, Georges (1894–1966), 193–194 Les Houches Physics Summer School, 99–100, 149 Lick Observatory, 53, 56, 82, 136, 156–157, 161 Lifshitz, Evgeny (1915–1985), 73–74 Liller, Martha (Martha Locke Hazen) (1931–2006), 219 Liller, William (b. 1927), 213 Limb darkening (solar), 93 Limber, D. Nelson (1928–1977), 82 Lindblad, Bertil (1895–1965), 109, 160 Lindblad, Per Olaf (b. 1927), 109 Lippincott, Sarah Lee (1920–2019), 120 Local Group (of galaxies), 196, 197 Local Supercluster, 194 Lowell, Percival (1855–1916), 157–158 Lowell Observatory, 94, 96, 141; image tube spectrograph, 131, 136, 161; Morgan telescope, 131; Perkins telescope, 131, 136, 140, 161; Rubin’s observing time, 136, 139, 140, 147, 161–162, 163 Lynden-­Bell, Donald (1935–2018), 100, 207 Lynds, Beverly T. (b. 1929), 215 Lynds, C. Roger (b. 1928), 147

306 I n d e x M101, 178 M31. See Andromeda Galaxy M33. See Triangulum Galaxy M51, 174 M81, 174, 178 M87, 203 M95, 203 Maddox, John, 211–212 Makemson, Maud (1891–1977), 30, 34–35, 36, 37, 43–44, 93, 123 Marrison, Joyce, 52 Matthews, Thomas, 137 Mayall, Nicholas U. (1906–1993), 155, 160 McCarthy, Martin F., SJ (1923–2010), 112, 113–119, 120, 128, 133, 139, 140, 141–142, 237, 243 McDonald Observatory, 104, 110, 130, 135–136, 155, 160 McNally, Derek (1934–2020), 224, 226 McNally, Paul A., SJ (1890–1955), 89 Mead, Jaylee Burley (1929–2012), 106–107, 108–109, 111 Menzel, Donald H. (1901–1976), 19, 49, 50 Mercury (magazine), 225; Rubin interviewed by Sally Stephens, 75, 247 Metagalaxy, 60, 96 Michell, John (1724–1793), 179 Michigan symposium (1953), 76, 79–81 Milky Way (the Galaxy), 17, 18; dynamics, 54, 55, 88, 101, 169; mass, 170, 184; nucleus, 174; radio observations, 154 rotation, 55, 56, 86–88, 107, 108, 111–112, 125, 130, 142; spiral structure, 55, 86–88, 107, 152 Minkowski, Rudolf (1895–1976), 137, 167 ­ atter Missing mass. See Dark m Mitchell, Maria (1818–1889), 28–29 Mockros, Carol, interview of Rubin, 206, 232, 250 Montgomery Ju­nior College, Takoma Park, 88, 89 Morgan, William W. (1906–1994), 87 Morrison, Philip (1915–2005), 53, 58, 78

Mount Wilson and Palomar Observatories, 73, 124, 125, 130, 132. See also Mount Wilson Observatory; Palomar Observatory Mount Wilson Observatory, 56, 77, 79; 60-­inch telescope, 158; 100-­inch telescope, 77, 131, 159. See also Mount Wilson and Palomar Observatories Mullard Radio Astronomy Observatory, University of Cambridge, 137, 150, 171 Münch, Guido (1921–2020), 164 National Acad­emy of Sciences, 70–71, 227–230; Rubin’s membership, 222, 237 National Bureau of Standards, 71, 73, 92, 93, 109, 132 National Medal of Science: Rubin’s appointment to Committee, 241; Rubin’s award ceremony, 237–239; Rubin’s citation, 3, 238 National Organ­ization for ­Women, 223 National Radio Astronomy Observatory (NRAO), 154, 167, 170, 171, 174, 178, 196 National Research Council, 227–228, 229 National Science Board, 235, 241 National Science Foundation, 79, 93, 101–102, 105, 124, 222, 241; W ­ omen in Science programs, 224 Nature (journal), 55, 197, 211–212, 249 Nebulae, nature of, 156–158. See also Andromeda Nebula; Emission nebula; Galaxies; H II region; Orion Nebula; Spiral nebula Netherlands Universities Foundation for International Co-­Operation (NUFFIC), 102 Newton, Isaac (1642–1727), 166; law of universal gravitation, 166; shell theorem, 166 NGC 300, 182 NGC 3115, 181 NGC 3351, 203 NGC 4216, 206 NGC 4383, 203–204 NGC 4526, 206 NGC 4550, 206–207

307

Index

NGC 5383, 203 NGC 5506, 203 NGC 5548, 138 NGC 5728, 203 NGC 6764, 202 NGC 7469 Nicodemus, Julia, 4 Nobel Prize in Physics, 53, 250–251 NUFFIC (Netherlands Universities Foundation for International Co-­Operation), 102 Nuffield Radio Astronomy Laboratories, University of Manchester, 170 Nyenrode ­Castle, 102, 103 objective prism, 114 Observatoire de Haute Provence, 97 O’Connell, Daniel J. K., SJ (1896–1982), 141 Oleak, Hans (1930–2018), 157 Oort, Jan H. (1900–1992), 55, 87, 102, 103, 109, 160, 174, 181, 182 Öpik, Ernst (1893–1985), 159 Oppenheimer, Rebecca, 4 Orion Nebula, 35 Orogodnikov, Kirill (1900–1985), 61 Osterbrock, Donald (1924–2007), 80, 87, 214, 215 Ostriker, Jeremiah P. (b. 1937), 183, 184, 250 Owens Valley Radio Observatory, 137, 178 Palomar Observatory, 116, 137, 147, 204, 206; 18-­inch Schmidt, 181; 48-­inch Schmidt, 125, 126, 130; 200-­inch (Hale) telescope, 7, 78, 131, 137, 138, 145, 171, 201; “monastery,” 126, 142; Rubin’s observing run in 1965, 124–126, 142. See also Mount Wilson and Palomar Observatories Pease, Francis G. (1881–1938), 158 Peebles, P. James E. (Jim) (b. 1935), 183, 184, 197 Peery, Benjamin F. (1922–2010), 213 Peterson, Charles J., 177 Philadelphia, 8, 9, 10; Fels Planetarium, 22; Franklin Institute, 21–22; Hospital for ­Mental Diseases, 12

Philosophical Society of Washington, 65, 216–218 Planetary alignment of 1940–1941, 16 Pontifical Acad­emy of Sciences, 241–242 Populations, stellar, 77, 78, 86–87 Potsdam Observatory, 157 Prendergast, Kevin H. (1929–2004), 110, 120, 156 Press, Frank (1924–2020), 228 Preston, George (b. 1930), 213 Prince­ton University, 244 Proper motion, 54, 107 Proximity fuze, 64, 67, 130 Purcell, Edward A. (1912–1997), 87 quasars, 137–138, 139, 149, 150 quasi-­stellar objects (or sources). See quasars Queen’s University, Kingston, Ontario, Rubin cele­bration meeting, 245–246 Randall, Lisa (b. 1962), 250 Reddish, Vincent C. (1926–2015), 170 Religion, Rubin’s views, 242 Roberts, Morton S. (Mort) (b. 1926), 154–155, 170, 171, 177, 178, 179, 196 Rogstad, David H. (b. 1940), 178 Roman, Nancy G. (1925–2018), 80, 86 Roo­se­velt, Eleanor, 33 Roo­se­velt, Franklin D., 12, 31 Rosse, Lord (William Parsons, 3rd Earl of Rosse) (1800–1867), 156 Rotation curves (of galaxies), 108, 109–111, 119; barred spiral galaxies, 203; flat, 111–112, 154, 167, 169, 171, 174, 175, 178, 179, 182, 184, 186, 187, 236–237, 250; optical mea­sure­ ment, 109, 155–156, 161, 164–165, 176; radio mea­sure­ment, 178, 179, 184, 186–187; Rubin and Ford’s observing program, 178, 179, 185–186, 187, 189–191. See also Andromeda Galaxy; Galaxies; Milky Way Royal Astronomical Society, Gold Medal awarded to Rubin, 240–241

308 I n d e x Rubin, Allan (b. 1960), 102, 134, 237, 245, 246 Rubin, David (b. 1950), 58, 68, 85, 99 Rubin, Judith. See Young, Judith Rubin, Karl (b. 1956), 90, 99, 237 Rubin, Robert (Bob) (1926–2008): education, 49, 54, 63; employment, 63, 67, 90, 91–92, 109, 115, 139; engagement, 47–48; illness and death, 245; marriage, 46; meeting with Vera, 41–43; navy ser­vice, 48; support for Vera, 54, 56, 58, 59, 68, 70, 71–75, 93, 112, 115, 128, 140, 166, 173, 243, 248; travel with Vera, 123, 234, 235, 236 Rubin–­Ford effect, 196–198; criticism, 197, 198 Rubin’s Galaxy. See UGC 2885 Rudnicki, Konrad (1926–2013), 142 Russell, Henry Norris (1877–1957), 30 Rus­sian Empire, 5, 6, 9 Rus­sian Revolution, 7 Saar, Enn, 184 Salpeter, Edwin E. (1924–2008), 79, 81 Sandage, Allan R. (1926–2010), 81, 109, 116, 124–125, 126, 137, 140, 144, 147, 197 Schatzmann, Évry L. (1920–2010), 100 Scheiner, Julius (1858–1913), 157 Schmidt, Maarten (b. 1929), 137, 138, 140, 170 Schwartzschild, Martin (1912–1997), 60, 61, 62, 74, 182 Scott, Elizabeth L. (1917–1988), 82 Selinsgrove (Pennsylvania), 12–13; State Colony for Epileptics, 12 Ser­vicemen’s Readjustment Act. See GI Bill Seven Samurai, 197 Sex discrimination, 24–25, 209–210, 211–213. See also Cosmos Club Shapley, Harlow (1885–1972), 19, 60, 76, 83, 95, 196 Shapley-­A mes Cata­log, 95 Sharpless, Stewart (1926–2013), 87 Shaw, R. William (1904–1995), 49, 50–51, 54, 57 Shostak, Seth (b. 1943), 178

Singer, Maxine F. (b. 1931), 228 Sitterly, Charlotte Moore (1898–1990), 73, 86, 94 Slipher, Vesto (1875–1969), 17, 157–158, 167 Smith, Clayton A. (1934–1993), 106 Smith, Sinclair (1899–1938), 180, 181, 182 South Pole, Rubin’s visit in 1997, 235–236 Spiral nebula, 17, 18, 95, 157–158, 167. See also Galaxies Stahr, Martha. See Carpenter, Martha Stahr Stars: Cepheids, 159; classification, 113–114; faint blue, 125; ­g iant, 114; G-­t ype, 114, 116; O-­B, 107, 111, 117, 120, 125, 142, 144; variable, 125, 159 Supergalaxy, 95 Swarthmore College, 27–28 Teem, John, 219, 220 Third Cambridge Cata­logue of radio sources (3C), 137 3C 9, 138 3C 33, 140 3C 48, 137, 140 3C 196, 137 3C 273, 137–138, 139 3C 286, 137 Thonnard, Norbert (1943–2014), 177, 186, 188 Tinker, Katherine Prescott (1901–1980), 37 Ton 256, 140 Tousey, Richard (1908–1997), 40–41, 46 Trager, Scott C., 4 Treanor, Patrick J., SJ (1920–1978), 113 Triangulum Galaxy, 159, 178, 182 Trimble, V ­ irginia L. (b. 1943), 221–222 Turner, Kenneth C. (b. 1934), 154 Tuve, Merle A. (1901–1982), 64, 129, 131–135, 141, 149, 154, 233 21-­centimeter radio emission, 87, 88, 107, 169, 178, 182, 187, 196 UGC 2885, 188 Uhlenbeck, Karen K. (b. 1942), 228 United States Naval Observatory, 36, 71, 93, 106, 132, 151

309

Index

United States Naval Research Laboratory (NRL), 36, 40–41, 46, 71 Universe: anisotropy of expansion, 196–198; closure, 182–183, 186; dark m ­ atter content, 179–180, 183, 184, 188, 191; early, 66, 67, 73, 188; expansion, 17, 56–57, 137, 138, 148, 182–183, 184, 193–195; “island universe” hypothesis, 156, 159; origin, 66, 67, 182, 194; rotation, 55–60, 67, 194; scale, 17, 77, 78, 96; structure, 61, 159, 194; turbulence, 74, 83 University of California, San Diego, 115, 119 University of California at Santa Cruz, 4 University of Durham, 240 University of Illinois, 90 University of Michigan, 76. See also Michigan symposium University of Pennsylvania, 9, 27, 28 University of Texas, Austin, 103, 240 Urry, C. Megan (Meg) (b. 1955), 227 V-12 program, 48, 52 V-2 rockets, 41 Vassar Club of Washington, DC, 31, 84 Vassar College, 28, 30–31, 211; astronomy teaching, 34–35, 37–38; college life, 32–33; Commencement weekend, 45; foundation, 29; male students, 35–36; observatory, 37; Rubin as President’s Distinguished Visitor, 234; Rubin’s scholarship award, 27, 31; war­time changes, 32 Vatican Observatory, 112, 113, 142, 243; Vatican Advanced Technology Telescope, 114; Vatican Schmidt camera, 114; Vatican

Study Week, 243; Vatican Summer Schools, 243 Vera C. Rubin Observatory, 1 Vera Rubin Presidential Chair for Diversity in Astronomy, 4 Vilna (Lithuania), 5, 6 Virgo cluster of galaxies, 142, 143, 180–181, 194, 196, 197, 204–206 Volders, Louise, 178 Walker, Merle F. (b. 1926), 164 Washington Post, 61–62, 83–84, 219, 249, 250 Weinberger, Alycia, 232, 235, 245 Weizmann Institute, 241 Westerbork Synthesis Radio Telescope, 186 Westphal, James A. (1930–2004), 142 Whitmore, Bradley C., 177 Whitney, Mary Watson (1847–1921), 29 Williams College, 240 Wolff, Sidney Carne (b. 1941), 213 Works Pro­gress Administration, 12 World War II: conscription, 26; dropping of atomic bomb, 26; US declaration of war, 16 Yahil, Amos, 183, 184 Yale Scientific Magazine, 39 Yale University, 237 Yerkes Observatory, 110, 160 Young, Judith (Judy, née Rubin) (1952–2014), 3, 74, 85, 99, 196, 208, 215, 220, 237, 245, 246 Zwicky, Fritz (1898–1974), 2, 180–182