ASTROSTAR/SHUTTERSTOCK In Astronomy Women n the heady days of the space race, the Mercury Seven astronauts were celebrities, and the Moon’s silver face seemed, for the first time in human existence, close enough to touch. For many, space was a tantalizing promise of a wonderful future, beyond the strife of an increasingly divided Earth. For others, supremacy Iin space was the answer to the Cold War. And for yet others, space was a sign of Fighting profligate spending of time and energy on dreams, when reality desperately needed America’s attention.

NASA achieved its most spectacular When engineers needed to calculate first steps in those days, making heroes the trajectory for Alan Shepard’s his- for out of men and women who dared to toric suborbital flight, Johnson volun- push harder, dream bigger, and be teered. She told the men she worked smarter than anyone before them. with exactly where and how to shoot Those moments created titans in Shepard into the sky so he would American history, such as rocket pio- splash down safely in range of watchful neers Robert Goddard and Wernher Navy ships. By the time Glenn orbited Visibility Von Braun, or astronaut adventurers Earth, mechanical computers were John Glenn and Neil Armstrong. beginning to replace humans. But But many of the actors in this play Glenn, fearless as he was, wanted his From pre-NASA remain hidden in the wings. Now, path checked and his life in the hands decades after the work that should of someone he could look in the eye, days to Apollo, the have made them legendary, the black not an unfeeling machine. Johnson women who helped put the United was that person, matching the com- struggles of black States in space are finally having their puter decimal for decimal. And when stories told. Armstrong, Buzz Aldrin, and women in the early These women, though not the faces Michael Collins left Earth for the memorialized in crowded mission-con- Moon, Johnson used the powerful new space program trol room photos or seen waving from computers to calculate their trajectory catwalks before launching beyond as well. By the time she retired in 1986, Women who showed particular skill rarely came to Earth’s grip, were nonetheless stars in she had left her fingerprints on NASA and interest moved out of the comput- their own right. And one of the bright- missions from the agency’s first forays ing pool to work directly with specific light. Until now. est was Katherine Johnson. beyond Earth into the space shuttle era. engineering groups. This allowed Johnson and her colleagues, Johnson and others to break free of the by Korey Haynes A HUMAN Dorothy Vaughan and Mary Jackson, physical walls segregating them by race COMPUTER feature prominently in the new book and gender from the rest of the NASA Born in 1918 in White Sulphur Springs, Hidden Figures, by Margot Shetterly. team. Her work earned her NASA Virginia, Johnson loved numbers as The book, which came out in September achievement awards and landed her in a child. She started college at West 2016, is about to hit the big screen as a lists of both women’s and African- Virginia State University at age 15 and major motion picture. Johnson is the Americans’ success stories. But her blew through the school catalog’s listed lead character, played by Taraji P. work also landed men on the Moon, courses; her professor created new ones Henson of the Fox television show and she deserves — and is finally get- just for her. By 18, she had graduated Empire; Octavia Spencer and Janelle ting — recognition beyond these lesser- Top to bottom: Katherine Johnson, summa cum laude with degrees in math Monáe round out the cast as Vaughan known lists. So why are we only Mary Jackson, and and French. But career paths for black and Jackson, respectively. hearing her story now? Dorothy Vaughan, women were stark in the 1940s, even Johnson is arguably the most famous “She’s almost 98, and she’s still alive three of the “human computers” who with a mind as sharp as Johnson’s. She of a group of black women Langley and able to tell her own story,” helped usher in taught school for more than a decade Research Center hired to perform calcu- Shetterly says. “A lot of people have human spaceflight before joining the space race as one of lations during World War II. They were passed away, and so she’s around in a for NASA, and whose the women, black and white, whom known as the West Computers because moment when we’re looking for people story is just now being told in the NASA (and its predecessor, the National they worked in the segregated West like her. You open the news, and there book and film Hidden Advisory Committee for Aeronautics, or Area of Langley. Toiling as brainy beasts are a lot of really depressing stories out Figures. NASA NACA) hired as “computers”— people of burden, these women — and their there. And this is a positive African- to do the math that kept NASA running. white counterparts in the East wing — American story, it’s a positive female took math problems parceled out by story, it’s a positive American story, it’s Korey Haynes is a contributing editor to engineers and solved them with light- a great space story.” Astronomy. ning speed and meticulous accuracy. Johnson’s story, in fact, seems 2 3 role in history — that a switch flipped “There’s always a balancing act,” says in her mind. She began asking around Bill Barry, a NASA historian who for the women’s stories and realized worked as a consultant for the film. His there were easily enough to fill a book. team delighted in replicating the halls of She hadn’t even finished writing Virginia’s Langley Research Laboratory that book when film producer Donna in a disused hospital in Atlanta, right Giglotti optioned the rights for a down to the art on the walls. But they movie, based on only Shetterly’s were also patient with certain necessary 50-page book proposal. Screenwriter adjustments made in order for the film Allison Schroeder took the proposal to tell a cohesive story out of the jumble and many of Shetterly’s primary source of real people’s lives. materials and got to work. She focused While the film was never meant to on three of the women who shine par- be a documentary, Barry is satisfied ticularly brightly in Shetterly’s that the film will bring the key players research: Johnson, who was central to and events to life. the leading missions of NASA’s heyday A QUESTION OF Katherine Johnson sits at her desk, of space flight; Jackson, an energetic performing the sorts of calculations that young woman who smashed barriers in HISTORY eventually led to the Moon landing. NASA her advance from computer to engi- Another part of the balancing act, not neer; and Vaughan, one of NASA’s first so dissimilar from the question the Left to right: Janelle Monáe as Mary Jackson, Taraji P. Henson as Katherine Johnson, and Octavia Spencer black managers, who ran the segre- women themselves contemplated, is as Dorothy Vaughan in the film Hidden Figures, based on the works of the women and their colleagues in victorious return to Earth, but that gated West Area Computing Division. how much to talk about the challenges the early space program. 20TH CENTURY FOX milestone is only one small piece of the Schroeder was excited to tell the facing three black women in the ’60s, puzzle of “why now?” story of these women against the back- racing for the Moon when so much “There’s some kind of magic other drop of the most exciting science pro- stood in their way down on Earth. Duchess Harris, a professor of to extend their already advanced techni- thing,” Shetterly admits. “I have no gram in U.S. history. With “We really don’t even deal with American studies at Macalester cal knowledge, but African-Americans idea, but it just is happening of its own grandparents who worked for NASA, race,” observes Henson, who plays College, argues, “That’s not meritoc- were forbidden from many of the local accord.” and a love of numbers and strong Johnson in the movie. “Because you racy.” Harris has written her own book colleges because of segregation laws. The women all her own, Schroeder prom- know what was going on in the ’60s. . . . about the West Area computers, nearby Hampden Institute, a well- THE SILVER ises, “I was born to write this.” We deal with how to rise above it. At Hidden Human Computers. Like respected black university, supplied SCREEN TOUCH But she had her work cut out for the end of the day, how do we get this Shetterly, she has a personal connection much of the desired coursework. Shetterly is one of the people who has her. Unlike the popular Apollo 13 film man on the Moon?” to these women: Miriam Daniel Mann, Compounding the problem, NASA’s long known not only Johnson’s name, — which relied on hours of recorded Barry agrees. “They were focused one of the Langley computers, was her standard position for hiring women was but many women like her. Shetterly conversations and minute-by-minute on the mission,” he says. “So if you had grandmother. She points out that the as a computer — a subprofessional posi- grew up in Hampton, Virginia, in accounts of the event for screenwriters the skill set to do the mission, they put land Langley stands on was, until 1950, tion that paid half an engineer’s salary, Langley’s backyard. Her father worked to insert directly into the movie you to work, and who cares about the a plantation. While NASA extended even for men and women with identical Katherine Johnson receives the Presidential at Langley as a research scien- about a single, compact rules.” But Barry also admits there science jobs to black employees, the degrees. While NASA gave a few black Medal of Freedom for her work ushering in tist. If anything, it took event — scant evidence were rules even NASA wouldn’t break, segregation of the times meant race was women an important foothold, the deck the age of human spaceflight. NASA / BILL INGALLS her this long to tell While existed from which such as segregated restrooms and a still a constant presence in their lives. was very much stacked against them. the women’s story Hidden Figures designated cafeteria area. Many NASA employees took classes But Henson is convinced that the because for many the film was could draw. film doesn’t need to discuss race — or almost tailor-made for the big screen. years, their work never meant to be While Johnson’s gender — to make powerful statements The roots of her computing legacy didn’t seem like a documentary, Barry work is well pre- about representation. “As I’m doing my reach from World War II through the much of a feat. served in his- research,” she recalls, “I see all of this looming threat of the Cold War and the “I feel like it is satisfied that the tory, she recalls NASA footage, and I don’t see any strife and successes of the civil rights was probably one film will bring the her day-to-day women, not even white women. There movement, hurtling through all of it in of the greatest gifts key players and interactions only was a west wing of computing and an the pursuit of space dreams. She was a in my life just grow- by memory. And east wing of computing, and they’re natural fit in an agency that broke sci- ing up thinking this events to life. in a story that spans just erased from history. . . . It blows my entific barriers and never stopped ask- was normal,” she says. decades — Shetterly’s mind that little girls don’t know that ing questions — except that Johnson “There was nothing to me book opens in the height they can do this.” and her fellow computers were breaking that was out of the ordinary about of World War II and follows racial as well as scientific ground. either living in a community with a lot Johnson until her retirement — the THE SPACE WOMEN In 2015, President Barack Obama of scientists or living in a community movie is obliged to condense multiple OF TOMORROW awarded the real Katherine Johnson with a lot of African-American scien- historical people into a few characters, Spreading the women’s message is both the Presidential Medal of Freedom. tists or living in a community with a the better for the audience to track and an important first step, and an incred- And in May 2016, Langley, where lot of female scientists and engineers connect with. For instance, Kevin ibly rewarding one. Many hope that Johnson spent her NASA career, dedi- and such. It seemed totally normal.” Costner plays a character stitched seeing Johnson on the big screen will cated a building in her name. NASA It wasn’t until Shetterly explained together out of real-life details from trumpet her name far beyond NASA dedicated the new research facility on the West Computers to her husband multiple flight directors and adminis- In another still from the film Hidden Figures, the human computers gather around a screen write-ups and awards. the 55th anniversary of Glenn’s — and witnessed his wonder at their trators in NASA’s history. during an important space launch. 20TH CENTURY FOX But the Hollywood story, and even

4 5 OTHER IMPORTANT FIGURES EMERGING FROM HISTORY’S SHADOW

Dorothy Vaughan sits with Leslie Hunter and Vivian Adair (left to right); all three women worked as Melba Roy Mouton, pictured next to an electronic computer, was the leader of a group of human computers who helped track Echo satellites human computers. NASA in the early 1960s. NASA Miriam Daniels Mann was hired at the same time as Dorothy Vaughan, in 1943. FOR THE Refusing the indignity of segregation in Shetterly’s more in-depth book, are only bulky calculator to computer punch cards work with another woman on a project. decades traveling to classrooms and her supposedly enlightened workplace, narrow peeks into the rich history of the — women’s participation in computing “This film offers us an opportunity GREATER GOOD meeting school groups, encouraging Mann stole the signs marking the women who provided the bedrock of fields flagged as the field advanced. And to really reflect on how science was done It’s also noteworthy that the human more women to follow in her “colored” section of the cafeteria for NASA’s endeavors. Last year, Nathalia Holt computers’ stories center not on one years. Her granddaughter, Duchess less than a hundred African-American then, and why community took the footsteps. Harris, is now researching the stories released Rise of the Rocket Girls, about the women have earned Ph.D.s in physics. structure it did, including the fact that lone genius, but on brilliant women “She would always include other of all the West Computers. DEWITT WALLACE women of the Jet Propulsion Laboratory, Ever. because of segregation, sometimes it was who were part of a team. Science is people,” says Henson, who has come LIBRARY AT MACCALASTER COLLEGE whose calculations guaranteed the success The reasons for this are manifold and easier for people to create community often seen as a lone wolf endeavor, ide- not only to admire, but to adore the of rocket flights and planetary missions. complex, but it is a self-perpetuating prob- because they were forced into it,” she alizing individuals like Albert Einstein woman she portrays. “Because she Holt credits their legacy to JPL’s retaining lem. With so few black women in these says. “Now the segregation is less visible or . But NASA knows it’s teamwork. But it was her more women-powered space teams than fields, even those who complete advanced or less present, but I think a lot of times has always been about team efforts. calculations.” elsewhere in the NASA family, where degrees can feel unwelcome at their work just less visible, and it can be Studies show that women are “If you’ve done an answer to a prob- female team leads are hard to come by. But and find themselves treading ground not harder for people to find drawn to jobs that fos- lem . . . yours is the answer,” Johnson her book tells the story of only one center so dissimilar from Johnson’s days, the community.” “Our ter cooperation and said in her dedication ceremony. And and its largely white team. Elsewhere, black social barriers less visible but still extant. Studies show that have a clear impact, she is proud of her years of service: women struggled up a steeper hill. And seeing few black women in those as early as middle institutional and that physics’ “When they pulled out a few notes to Harris continues her own study of the workspaces can discourage young potential school, girls and bias against black reputation for cold write down what I had worked on, the women of Langley, her research finding a scientists, who see no one like themselves minorities are calculation turns guy had 20 pages.” home in museums and classrooms instead to whom they can aspire. opting out of women scientists is many of them off Johnson said she was pleased to see of in popular media. She hopes targeting Chanda Prescod-Weinstein, a professor science not so strong that it is at young ages. the emerging pattern of recognizing children with these women’s stories will of physics at the University of Washington, because they literally hard for It is not just women’s work, something she says men provide role models for kids who often counts herself among the few black women enjoy it less or the faces of have long gotten credit for. don’t see scientists who look like them. with physics Ph.D.s. “Our institutional bias even see them- people to imagine Langley’s human Prescod-Weinstein anticipates the One of the younger computers, Speaking for NASA, Barry agrees. “We against black women scientists is so strong selves as less capa- computers that are film as “an opportunity to write history Christine Darden began working at I exist.” NASA in 1967. She rose to the title of hope [the Hidden Figures film] encourages that it is literally hard for people to imagine ble, but because they important, but the correctly, finally, about what has been engineer in 1973, one of the few women more young people to go into the field. I exist,” she says. “I overcame it. The people don’t see science as some- ways in which they did the nature of black contributions to of any color at the time to hold that From our perspective, there’s lots of fallout who hired me overcame it.” thing that is for them. their jobs. American intellectual history.” position. Since then, she has published benefits from telling this kind of story.” She points to the “nonlinearity” of prog- Understanding that not only can “Somebody wants to know some- For many reasons, the West more than 50 papers and is recognized as a world expert in sonic booms. NASA Those benefits are desperately needed. ress in STEM diversity. (STEM refers to the black women excel in space science, but thing,” said the 98-year-old Johnson, Computers’ names are never likely to The space science fields, engineering in disciplines in science, technology, engineer- they have been doing so all along, could explaining her math skills in a speech rise to the level of Neil Armstrong’s or particular, suffer acutely from a lack of ing, and math.) While Johnson and the make a huge impact on the next genera- at her own Langley dedication cer- Jim Webb’s renown. But the solutions women and minorities. While the earliest other Hidden Figures characters worked in tion of scientists. “It really highlights emony. “Help them. Help anybody you were theirs. computer programmers were exactly these a team with other black women, Prescod- the importance of not separating the can help.” She saw her love of math as Women like Katherine Johnson have human computers of NASA — adapting Weinstein says that she was 13 years into science from the history of how it was a way to further America’s dreams. always been part of the story. It’s high their math from pencil and paper and her research before she found the chance to produced,” Prescod-Weinstein says. After her retirement, she spent time we told it. 6 7 Women’s work How VE RUBIN discovered dark matter This famous astronomer carved herself a well-deserved place in history, so why doesn’t the Nobel committee see it that way? by Sarah Scoles

In the late 1970s, Vera Rubin and Kent In the past few years, scientists have gotten that free trip to Ford of the Carnegie Institution of Washington stared, con- Sweden for demonstrating that neutrinos have mass, for fused, at the punch-card readouts from their observations of inventing blue LEDs, for isolating graphene’s single carbon the Andromeda Galaxy. The vast spiral seemed to be rotating layer, and for discovering dark energy. All of these experiments all wrong. The stuff at the edges was moving just as fast as the and ideas are worthy of praise, and some, like dark energy, stuff near the center, apparently violating Newton’s Laws of even tilted the axis of our understanding of the universe. But Motion (which also govern how the planets move around our the graphene work began in 2004; dark energy observations Sun). While the explanation for that strange behavior didn’t happened in the late ’90s; scientists weighed neutrinos around become clear to Rubin until two years later, these printouts the same time; and blue LEDs burst onto the scene a few years represented the first direct evidence of dark matter. before that. Rubin’s work on dark matter, on the other hand, Scientists now know that dark matter comprises some 84 took place in the 1970s. It’s like the committee cannot see her, percent of the universe’s material. Its invisible particles swarm although nearly all of astrophysics feels her influence. and stream and slam through the whole cosmos. It affects how Rubin is now 87. She is too infirm for interviews. And stars move within galaxies, how galaxies tug on each other, and because the Nobel can only be awarded to the living, time is how all that matter clumped together in the first place. It is to running out for her. the cosmos like air is to humans: ubiquitous, necessary, unseen but felt. The discovery of this strange substance deserves a Vera Rubin, with collaborator Kent Ford, is responsible for finding Nobel Prize. But, for Rubin, none has come, although she has dark matter, one of the most fundamental discoveries of the past century long been a “people’s choice” and predicted winner. in astrophysics. Yet a Nobel Prize still eludes her. PETER GINTER, GETTY IMAGES

8 9 astronomy at Cornell University in Ithaca, New York. Ensconced in Ithaca’s gorges and working with astronomer Martha Stahr Carpenter, Rubin began to hunt around for a master’s thesis idea. Carpenter was obsessed with galaxies and how their innards moved. “Her course in galaxy dynamics really set me off on a direction that I followed almost my entire career,” said Rubin. One day, her new husband, Robert Rubin, brought her a journal article by astronomer George Gamow. In it, Gamow wondered, “What if we took the way solar systems rotate and applied it to how galaxies move in the universe?” Our near neighbor, the spiral Andromeda Galaxy (M31), was Rubin’s Rubin wondered, “What if, indeed?” and first target in her study of galaxy rotation. While telescopes reveal took that wonder a step further. She began glittering stars and glowing clouds of dust and gas, Rubin’s studies to measure how galaxies moved. Did some Rubin and Kent Ford (white hat) check on their equipment at Lowell Observatory in 1965 during one implied an additional invisible halo of dark matter. NASA/JPL-CALTECH cluster together in their travel through space of their first observing runs together. CARNEGIE INSTITUTION, DEPARTMENT OF TERRESTRIAL MAGNETISM A young Vera Rubin was already observing the stars when she was — perhaps rotating around a pole, like the an undergraduate at Vassar College, where she earned her bachelor’s planets rotate around the common Sun? degree in astronomy in 1948. ARCHIVES & SPECIAL COLLECTIONS, VASSAR COLLEGE LIBRARY Was it random? their accomplishments and status and will inevitably be exposed While gathering data, she found a plane that was denser with gal- as frauds. “One of the biggest problems in my life [during] those Emily Levesque, an astronomer at the University of Washington “She went to her room, she cut up paper into a skirt image, axies than other regions. She didn’t know it at the time, and no one years was really attempting to answer the question to myself, ‘Will in Seattle who has spoken out about Rubin’s notable lack of a Nobel, and she stuck it on the little person image on the door of the else would discover it for years, but she had identified the “superga- I ever really be an astronomer?’ ” says, “The existence of dark matter has utterly revolutionized our bathroom,” says Bahcall. “She said, ‘There you go; now you have a lactic plane,” the equator of our home supercluster of galaxies. The “real astronomers” pounced on her result (except, notably, concept of the universe and our entire field; the ongoing effort to ladies’ room.’ That’s the type of person Vera is.” When she presented her thesis, William Shaw, one of her advis- Martin Schwarzschild, who defined how big black holes are). “My understand the role of dark matter has basically spawned entire Rubin has continued to champion women’s rights to — and ers, told her just two things: One, the word data is plural. Two, her paper was followed by a rather acrimonious discussion,” she told subfields within astrophysics and at this point. rights within — astronomy. “She frequently would see the list of work was sloppy. But, he continued, she should consider present- DeVorkin. “I didn’t know anyone, so I didn’t know who these Alfred Nobel’s will describes the physics prize as recognizing ‘the speakers [at a conference],” says Bahcall, “and if there were very ing it at the American Astronomical Society (AAS) meeting. Or, people were that were getting up and saying the things they said. most important discovery’ within the field of physics. If dark matter few or no women speakers, she would contact [the organizers] and rather, she should consider having it presented for her. Because she As I recall, all the comments were negative.” doesn’t fit that description, I don’t know what does.” tell them they have a problem and need to fix it.” was pregnant with her first child — due just a month before the Her paper was never published. There’s no way to prove why Rubin remains prize-less. But a But, as Rubin told science writer Ann Finkbeiner for Astronomy meeting — and not a member of the society, he graciously volun- webpage showing images of past winners looks like a 50th-reunion in 2000, she is “getting fed up. . . . What’s wrong with this story is teered to give a talk on her results. “In his name,” she clarified to Back into the field publication from a boys’ prep school. No woman has received the that nothing’s changing, or it’s changing so slowly.” DeVorkin. “Not in my name. I said to him, ‘Oh, I can go.’ ” For six months after her first child was born, Rubin stayed home. Nobel Prize in physics since 1963, when Maria Goeppert Mayer She called her talk “Rotation of the Universe,” ascribing the But while she loved having a child, staying at home emptied her. shared it with Eugene Wigner and J. Hans Jensen for their work An early start ambitious title to “the enthusiasm of youth,” as she recalled. At She cried every time The Astrophysical Journal arrived at the on atomic structure and theory. And the only woman other than Rubin, born in 1928, first found her interest in astronomy when the AAS meeting, she didn’t know anyone, and she thought of house. “I realized that as much as we both adored this child, there Mayer ever to win was Marie Curie. With statistics like that, it’s her family moved to Washington, D.C. Windows lined the herself as a different category of human. “I put these people in a was nothing in my background that had led me to expect that hard to believe gender has nothing to do with the decision. wall next to her bed. She watched the stars move, distant and very special class. They were professional astronomers, and I was [my husband] would go off to work each day doing what he loved Some, like Chanda Prescod-Weinstein of the Massachusetts unreachable. “What fascinated me was that if I opened my eyes not,” she said, showcasing a classic case of impostor syndrome, a to do, and I would stay home with this lovely child,” she said to Institute of Technology, have called for no men to accept the prize during the night, they had all rotated around the pole,” she told psychological phenomenon in which people don’t feel they deserve DeVorkin. “I really found it very, very hard. And it was he who until Rubin receives it. But given the human ego and nearly David DeVorkin in 1995 as part of the American Institute of insisted that I go back to school.” million-dollar prize amount, that’s likely to remain an Internet- Physics oral history interview series. “And I found that inconceiv- She was accepted into a Ph.D. program at Georgetown only call to action. able. I just was captured.” Flat rotation curves University in Washington, D.C., and she discovered that galaxies She started watching meteor showers and drew maps of the did clump together, like iron filings, and weren’t randomly strewn. No room for women streaks, which striped the sky for a second and then were gone. She The work, though now part of mainstream astronomy, was largely Rubin isn’t unfamiliar with discrimination more outright than the built a telescope and chose astronomical topics for English papers, Observed ignored for decades; that lack of reinforcement perhaps contributed from spectra Nobel committee’s. Former colleague Neta Bahcall of Princeton using every subject as an opportunity to peer deeper into the uni- to her lingering, false feeling that she wasn’t a real astronomer. As University tells a story about a trip Rubin took to Palomar verse. “How could you possibly live on this Earth and not want to E she described it, “My husband heard my question often, ‘Will I ever xp e ec Observatory outside of San Diego early in her career. For many study these things?” she wondered, retelling the story to DeVorkin. Velocity x te really be an astronomer?’ First I thought when I’d have a Ph.D., ten d from t of visible years, the observatory was a researcher’s man cave. Rubin was one While her parents supported her, it was a different story at galaxy I would. Then even after I had my Ph.D., I wondered if I would.” of the first women to gain access to its gilt- school. When she told her physics teacher, for edged, carved-pillar grandeur. But while she was instance, that she had received a scholarship Distance from galaxy center Mysteriously flat allowed to be present, the building had no wom- “The existence of to Vassar College, he said, “As long as you stay In 1965, after a stint as a professor at Georgetown, Rubin began en’s restroom, just urinal-studded water closets. DARK MATTER away from science, you should do OK.” her work at the Carnegie Institution’s Department of Terrestrial She didn’t. If galaxies were only the stars, dust, and gas that astronomers can see, Magnetism in Washington, D.C., where she met astronomer Kent Former Astronomy Associate Editor Sarah Scoles has utterly revolutionized then you would expect the red line: Gravity pulls most strongly and objects Ford and his spectacular spectrometer, which was more sensitive is a freelance writer living in the San Francisco area. therefore rotate more quickly where most of the matter resides. But Rubin’s than any other at the time. our concept of the Rotation of the universe and hundreds of later observations revealed that the speed of the galaxy’s She is writing a book on astronomer and SETI pioneer universe and After receiving her bachelor’s degree from outer material is the same as the speed of matter closer in, indicating some A spectrometer takes light and splits it up into its constitu- Jill Tarter. Vassar, Rubin enrolled in graduate school in enormous invisible mass hurrying things along. ASTRONOMY: ROEN KELLY ent wavelengths. Instead of just showing that a fluorescent bulb our entire field.” 10 — Emily Levesque 11 A dark answer THE BULLET THAT KILLED MOND Dark matter existed as a concept, first proposed by astronomers like Jan Oort in 1932 and Fritz Zwicky in 1933, who also noticed discrepancies in how much mass astronomers could see and how much physics implied should be present. But few paid their work any attention, writing their research off as little more than cos- mological oddities. And no one had bagged such solid evidence of it before. And because no one had predicted what dark matter’s existence might mean for galaxy dynamics, Rubin and Ford ini- tially didn’t recognize the meaning of their flat rotation curves. “Months were taken up in trying to understand what I was looking at,” Rubin told journalist Maria Popova. “One day I just decided that I had to understand what this complexity was that I was looking at, and I made sketches on a piece of paper, and sud- denly I understood it all.” If a halo of dark matter graced each galaxy, she realized, the Rubin operates the 2.1-meter telescope at Kitt Peak National Observatory. Kent Ford’s spectrograph is attached so they can measure the speed mass would be spread throughout the galaxy, rather than concen- of matter at different distances from galaxies’ centers. NOAO/AURA/NSF trating in the center. The gravitational force — and the orbital The Bullet Cluster is often claimed as a smoking gun for dark matter. speed — would be similar throughout. Rubin and Ford had discovered the unseeable stuff that influ- Dark matter is hard to believe. We can’t see it, and it barely interacts return to Rubin’s interest in galaxy dynamics. “People had inferred ences not only how galaxies move, but how the universe came with normal matter. Vera Rubin and others inferred its presence from what galaxy rotations must be like,” said Rubin, “but no one had to be and what it will become. “My entire education highlighted Isaac Newton’s laws about gravity. But what if Newton was wrong? really made a detailed study to show that that was so.” Now, because how fundamental dark matter is to our current understanding of In 1983, Mordehai Milgrom suggested Modified Newtonian Rubin continued to work at the Carnegie Institution’s Department of Ford’s out-of-this-world spectrograph, they could turn the infer- astrophysics,” says Levesque, “and it’s hard for me to imagine the Dynamics (MOND) as a more palatable explanation. He proposed that of Terrestrial Magnetism until recently, still fascinated by galaxies and studying how they move in the universe. AIP/EMILIO SEGRE VISUAL ARCHIVES gravity behaves differently in low-acceleration regions such as the out- ences into observations. field or the universe without it.” skirts of galaxies. It neatly explained most of the galaxies Rubin had When they pointed the telescope at M31, they expected to Within a few years of the M31 observations, physicists like observed without invoking a mysterious new form of matter. see it rotate like the solar system does: Objects closer to the Jeremiah Ostriker and James Peebles provided the theoretical But MOND can’t explain objects such as the Bullet Cluster, the result center move faster than ones toward the edge. Mass causes grav- framework to support what Rubin and Ford had already shown, and No matter which way or where scientists measure Rubin’s discov- of two colliding galaxy clusters. Gravitational lensing (shown in blue) ity, which determines the speed of rotation. Since most of the dark matter settled firmly into its celebrated place in the universe. ery, it’s huge. maps most of the mass to the bright stellar material. But galaxies carry stars, dust, and gas — and therefore gravity — is clustered in In more recent years, the Planck satellite measured the dark And while no one knows what all the dark matter is, scien- most of their normal mass in hot gas (shown in pink from X-ray emis- sion) and waylaid in the middle of the collision thanks to drag forces. the middle of galaxies, the stuff on the periphery shouldn’t feel matter content of the universe by looking at the cosmic micro- tists have discovered that some small fraction of it is made of Just as Rubin showed with her rotation curves, the Bullet Cluster much pull. They concentrated their observations on Hydrogen-II wave background, the radiation left over from the Big Bang. The neutrinos — tiny, fast-moving particles that don’t really interact proves that galaxies hold far more mass than our telescopes can see. (HII) regions — areas of ionized hydrogen gas where stars have clumps of matter in this baby picture of the universe evolved into with normal matter. Measurements from the cosmic micro- And neither Newton nor MOND can explain that without the myste- recently formed — at different distances from the galaxy’s center. the galaxy superclusters we see today, and it was dark matter that wave background, like those being taken by experiments called rious power of dark matter. — Korey Haynes But no matter how far out they looked, the HII regions seemed to clumped first and drew the regular matter together. POLARBEAR in Chile and BICEP2 and BICEP3 in Antarctica, be moving at the same speed. They weren’t slowing down. Data from galaxy clusters now also confirms dark matter and will help pin down how many neutrinos are streaming through “We kept going farther and farther out and had some disap- helps scientists measure how much of it exists within a given the universe and how much of the dark matter they make up. glows white, for instance, it would show how much of that light pointment that we never saw anything,” says Ford. group — a modern echo of Zwicky’s almost forgotten work. When Some setups, like the Gran Sasso National Laboratory in Italy is blue and how much yellow, and which specific wavelengths of “I do remember my puzzling at the end of the first couple of light from more distant sources passes near a cluster, the gravity and the Deep Underground Science and Engineering Laboratory blue and yellow. Ford’s spectrometer stood out from others at the nights that the spectra were all so straight,” said Rubin, referring — from the cluster’s huge mass — bends the light like a lens. in South Dakota, are trying to detect dark matter particles time because it employed state-of-the-art photomultipliers that to the unchanging speed of the various HII regions. The amount of bending can reveal the amount of dark matter. directly, when they crash into atoms in cryogenically cooled let researchers study small regions of galaxies, and not simply the They didn’t know what, if anything, it meant yet. tanks filled with liquefied noble gases. So far, they haven’t man- entire objects. The project took years and involved treks westward to telescopes. aged to capture a dark matter particle in action. But researchers With this device, Ford and Rubin decided to look at quasars — Ford recalls flying to Flagstaff, Arizona, dragging the spectrograph are taking dark matter — whatever it is — into account when distant galaxies with dynamic, supermassive black holes at their from the closet, working for a few nights at Lowell, and then throw- they think about how the universe evolves. centers. But this was competitive work: Quasars had just been ing the instrument into a Suburban so they could drive it to Kitt The Nobel committee may overlook Rubin, passing by her as discovered in 1963, and their identity was in those days a mystery Peak. “We both thought we were better at guiding the telescope,” he if they can’t see what all of astrophysics feels. But that won’t hurt that everyone wanted to solve. Rubin and Ford didn’t have their says. They raced each other to be first to the eyepiece. her legacy, says Levesque: It will hurt the legacy of the Nobel own telescope and had to request time on the world-class instru- The data came out on punch cards, which Rubin spent hours itself. “It would then permanently lack any recognition of such ments that astronomers who worked directly for the observatories analyzing in a cubbyhole beneath a set of stairs. They all showed groundbreaking work,” Levesque says. could access all the time. Rubin didn’t like the competition. the same thing. Rubin herself has never spoken about how she deserves a “After about a year or two, it was very, very clear to me that that Rubin and Ford moved on from M31 to test other galaxies and Nobel Prize. She simply continued her scientific work until was not the way I wanted to work,” she told their rotation curves. Like an obsessive art- recently, all the while influencing the origins, evolutions, and Alan Lightman in another American Institute of ist, each painted the same picture. Although fates of other scientists. “If they didn’t get a job or they didn’t get Physics oral history interview. “I decided to pick “My entire education the result contradicted theory, and although a paper published, she would cheer people up,” says Bahcall. “She a problem that I could go observing and make highlighted how they didn’t understand what it meant, no one kept telling her story about how there are ups and downs and you headway on, hopefully a problem that people fundamental doubted their data. “All you had to do was stick with it and keep doing what you love doing.” would be interested in, but not so interested [in] show them a picture of the spectrum,” Rubin Rubin measures spectra at the Carnegie Institution’s Department of Rubin, herself, loves trying to understand the universe, and DARK MATTER is to Terrestrial Magnetism. It was such measurements that revealed to Rubin that anyone would bother me before I was done.” told Lightman. “It just piled up too fast. Soon that the outer regions of galaxies rotated as fast as their inner regions — in doing so, she has changed everyone’s understanding of it. Rubin and Ford chose to focus on the nearby our current understanding there were 20, then 40, then 60 rotation curves, indicating some huge amount of missing mass that would later be realized That carries more weight than some medal from Sweden. But let Andromeda Galaxy (M31). It represented a of astrophysics.” and they were all flat.” AL. ET MAGELLAN/U.ARIZONA/D.CLOWE WFI; ESO NASA/STSCI; MAP: LENSING AL.; ET OPTICAL: MAGELLAN/U.ARIZONA/D.CLOWE NASA/STSCI; AL.; ET NASA/CXC/CFA/M.MARKEVITCH X-RAY: CLUSTER) (BULLET as dark matter. AIP/EMILIO SEGRE VISUAL ARCHIVES Sweden recognize that for what it is: worthy of a prize. 12 — Emily Levesque 13 The Universe According to Emmy Noether How a deceptively simple theorem from a century ago still shapes modern physics.

BY STEVE NADIS ILLUSTRATIONS BY JAY SMITH PICTORIAL PARADE/HULTON ARCHIVE/GETTY IMAGES PARADE/HULTON PICTORIAL

14 155 accomplished if society andaccomplished ifsociety impact algebra onboth and 16 physics. There’s notelling that impeded herpursuit fate had more been kind. what she might else have of mathematics, Noether spent bucking asystem In her53years, many had anextraordinary I symmetry andconservation is how we describeourworld.” our methods, ourtheoriesandintuition.Thelinkbetween said acenturylater. “Herbasicinsightsonsymmetryunderlie modern physics,” DurhamUniversity physicist Ruth Gregory known simply asNoether’s theorem. particles toblack holes, draws heavily uponthistheorem, now Today, thephysical world, ourcurrent grasp of from subatomic nature, aconnectionthatof physicists have exploited ever since. laws energy) andthesymmetries (suchastheconservation of greater impact,uncovered anintimate linkbetween conservation Germany. Theothertheorem, which would ultimately have afar two theoremsThat sheproved was oneof that year inGöttingen, — but everything works outwhen thespaceissufficiently large. conserved “locally” —that is, space inanarbitrarily smallpatch of gladly acceptedthechallenge. a young mathematician withnoformal academicappointment, destroyed. Total energy issupposedtoremain constant.Noether, energy, which states that energy canchangeforms but cannever be from surgery toremove an ovarian cyst. Einstein.Shedied just 18monthslater duetocomplications of landed ajobat BrynMawr CollegeinPennsylvania, with thehelp academia inNaziGermany. Soonafter, she leftthecountryand later, shelostherjobwhen sheandotherJews were castoutof Göttingen, where shewas allottedamodestsalary. But11years finally becameanuntenured associate math professor in1922 at receiving nopay. her triptoGöttingenin1915,shestayed onasalecturer, again occasionally fillingin for herfather asasubstituteteacher. After official position, relying onherfamily for financial support while and spentnearly eightyears working there withoutpay oran Erlangen. Shereceivedat aPh.D. theUniversity of in1907 the final exams that she earnedanundergraduate degree. Noether hadtoauditclassesinstead.Eventually shedidsowell in universities didnotadmitwomen when shereached collegeage, so her mathematicianin thefootsteps father, of Max.ButGerman expertise couldhelpclearuptheproblem withgeneral relativity. had published someimportantpapers, andHilbertfeltthat her and was barely able togetaneducation inthefield. Yet she a curiouschoice. Shedidnothave anactualjobinmathematics it,Noether(pronounced NUR-tuh)appears tohaveface of been mathematicians tohelprescue Einstein’s masterwork? Onthe Who was thiswoman, calleduponby two renowned A LIFEOFWORK “It is hard to overstate the importance of Noether’s“It ishard tooverstate work theimportanceof in She resolved theissuehead-on,showing that energy may notbe After years of working essentially asavolunteer,After years of Noether toenrollIn 1904shewas permitted inadoctoral program Born inErlangen, Germany, in1882,Noetherhopedtofollow established physical principleknown asconservation of year. Itseemed that thetheorydidnotadhere toawell- general relativity, which hadbeenunveiled earlier inthe had cropped upinAlbertEinstein’s gravity, new theoryof GöttingentoinvestigateUniversity apuzzle. of Aproblem Hilbert andFelix Klein,invited Emmy Noethertothe theworld’sn 1915, two of topmathematicians, David

EMILIANA AND MONICA NOETHER VIA MATHEMATICAL ASSOCIATION OF AMERICA/FLICKR momentum namesake theorem perhaps hermostdurable contribution. great scientists,to secure withher herplaceinthepantheonof more kind.Nevertheless, work was herbody more thanenough of societyandfateelse shemighthave hadbeen accomplishedif both algebra (hermainfield)andphysics. There’s notelling what mathematics,pursuit of Noetherhadanextraordinary impacton momentum thoseterms. down afew of has acorresponding conservation law, andviceversa. Let’s break it,too.nonphysicists cangetthegistof unrelated conceptsthat is, today, almostobvious tophysicists. But Noether’s theorem isasimpleandelegantlinkbetween seemingly THE THICKOFTHEOREM or rotational invariance, leadstothe moves thesmoothiceasonanother. thesameway ononepartof movements (ortranslations) withinauniform space. Thepuck sayingis anotherway that physics of isnotaffected by linear space remains unchanged. Nothing willchange, however, theiceremains smoothand if theice, inthiscase—were tovary. —thesurfaceof space itself puck toalteritscourse, ortogainlosespeed,would beif be retained, orconserved. Theonly thingthat couldcausethe itsmassandvelocity,down. Itsmomentum,theproduct of will puck willcontinue toglideinastraight linewithoutever slowing on thepuckwhatsoever. conditions, Undertheseidealized the ice. Let’ssheet of furthersupposethat noexternal forces are acting puck glidingalongaperfectly smooth,endlessandfrictionless conservation law that corresponds toagiven symmetry. underlies agiven conservation law and,conversely, findingthe an explicit mathematical formula for findingthesymmetrythat until thenhadbeentreated separately. Thetheorem provides basic concepts—symmetriesandconserved quantities—that repeat thecalculation. or destroyed; onceyou’ve computed itsvalue, there’s noneedto not fluctuate over time. Energy, for example, cannotbecreated refers toaphysical quantitythat remains fixed andhencedoes The theorem also links the symmetry of “time translation”The theorem alsolinksthesymmetryof tothe indeed by any amount, theexperimental results will notdiffer. experiment onatable andthenrotate that table by 45degrees, or Physics, inotherwords, you doan hasnopreferred direction. If Noether’s theorem applies. A doesn’t symmetrytowhich alteritsappearance. Thisisthekindof symmetry sincerotating itby any degree, orafraction thereof, a diamond).Acircle, ontheotherhand, possessescontinuous 45-degree rotation yieldssomethingdifferent (commonly called “discrete” symmetry. Thesquare stilllooksthesame, whereas a it unchanged.Rotating asquare by 90degrees isanexample of an operation that canbedonetoanobjectorsystemthat leaves In her53years, many spentbucking asystemthat impededher Basically, itstates that every “continuous” symmetryinnature Similarly, Noether’s theorem shows that symmetryunderrotation, Noether’s theorem shows that thepuck’s Here’s thetheorem inaction:Imagine ahockey a glimpseof Noether’s theorem uncovered ahidden relationship between two , which measures how much anobjectisrotating.

is tied to its “symmetry of spacetranslation,”is tiedtoits“symmetryof which Symmetry

conservation law conservation of angular conservation of , inthiscontext, refers to conservation of conservation of , meanwhile, conservation of angularmomentum conservation of conservation of momentum conservation of conservation law symmetry 17 conservation of energy, so physics also doesn’t care if you do an Collider, would be “a reflection of all the Standard Model particles, experiment today, next Tuesday or the third Sunday in October. using a mirror that is slightly distorted,” explains Joseph Incandela, Physicists had known about the conservation of momentum, a physicist at the University of California, Santa Barbara. “The angular momentum and energy long before Noether’s theorem came particles on the other side of the mirror look just like Standard along. They are foundational precepts of classical mechanics. But it Model particles, except that their spins have been slightly shifted.” was not known that these hallowed laws shared a common origin, One possibility that has been associated with this assumed each bound to a particular symmetry. This new insight, which symmetry, says Incandela, is the conservation of something called sprang from Noether’s work, is a guiding principle that permeates r parity, which implies that the lightest supersymmetric particle has physics research, while informing our views of the universe at large. to be stable and can never decay. If r parity is indeed conserved, every ordinary particle’s unseen supersymmetric partner will conservation of energy PUTTING IT ALL TOGETHER eventually decay into the lightest supersymmetric particle, which soft particles Noether’s theorem applies not only to these intuitive symmetries — sticks around forever. That particle, whatever it may be, would be rotations and shifts in time or space — but also to more abstract, available in abundant quantities and could thus be a good candidate “internal” symmetries that underlie the forces of nature. for the mysterious dark matter believed to account for more than For example, the conservation of electric charge, a central one-quarter of the stuff in the universe. tenet of the theory of electromagnetism, stems from a symmetry related to details of the particle’s spin. Another example: A ILLUMINATING BLACK HOLES symmetry called isospin that allows electrons to be substituted for Noether’s theorem, however, is crucial to more than just the search event horizon neutrinos, and neutrinos for electrons, helped physicists develop for new particles; it extends to all branches of physics. Harvard a theory in the 1960s that unified the electromagnetic force and physicist , for example, has identified an infinite conservation of electric charge the weak force (which explains particle decays and radioactive number of symmetries related to soft particles, which are processes) into a single electroweak force. The conserved quantity particles that have no energy. These particles come in two varieties: here is “hypercharge” — a kind of charge, analogous to electric soft photons (particles that transmit the electromagnetic force) charge, that is associated with this electroweak force. A decade later, and soft gravitons (particles that transmit the gravitational force). black hole physicists devised a theory for the strong nuclear force, which binds Recent papers by Strominger and his colleagues, Stephen Hawking information protons and neutrons in the atomic nucleus. At the heart of this and Malcolm Perry of Cambridge University, suggest that material paradox force is something called color symmetry. (Color is a property falling into a black hole adds soft particles to the black hole’s of the quarks that make up protons and neutrons, which physicists boundary, or event horizon. These particles would in effect serve view as another kind of charge.) as recording devices that store information, providing clues about In the 1970s, physicists put all the known particles (including the original material that went into the black hole. color symmetry a few whose existence had not yet been confirmed, like the The idea proposed by the three physicists offers a new strategy Higgs boson) and the forces that govern their interactions — for addressing a long-standing conundrum in physics known as the electromagnetic, weak and strong — into a single theoretical the black hole information paradox. Hawking showed in the u c t γ H framework known as the Standard Model. 1970s that every black hole will eventually evaporate and disappear, According to Stanford University physicist Michael Peskin, potentially destroying all the information the object once contained Noether’s theorem was a basic tool in the construction of this about how it formed and evolved over time. The permanent loss d s b g amazingly successful model. “In quantum mechanics, you identify of information in Hawking’s scenario was troubling to theorists — two or three particles that are supposed to be tied by a symmetry including Hawking — as it would violate a cherished law of quantum

υe υμ υτ z0 and then see if the inferred conservation law is valid. That’s how physics holding that information, like energy, is always conserved. you learn whether it is a real symmetry of nature, and that’s how The presence of soft particles along the event horizon, and their the Standard Model was built” — through a cumulative, step-by- attendant symmetries, may point toward a way out of this dilemma. e μ τ W step process like this. It’s also how researchers are now trying to “We quickly realized through Noether’s theorem that there were move forward. conservation laws corresponding to the new symmetries that place Standard Model very stringent constraints on the formation and evaporation of A SUPER LEGACY black holes,” says Strominger, although he acknowledges this work The hunt is on to find new particles and deeper, broader symmetries is still at an early stage. Noether’s theorem is from which they stem, a process in which Noether’s theorem It is just one more setting in which Noether’s theorem looms continues to play a pivotal role. Much of the current effort focuses on large, and the list of examples keeps growing. “The relationship crucial to more than looking for signs of supersymmetry — a theory that postulates a between symmetries and conservation laws is a never-ending story,” symmetry between the particles that make up matter (fermions) and says Strominger. “One hundred years later, Noether’s theorem keeps just the search for new the particles that transmit forces, like electromagnetism (bosons). finding more and more applications.” particles; it extends to If supersymmetry is right, every known fermion has a yet-to-be- While no one knows what will come next, the incredible power, supersymmetry observed bosonic “superpartner,” and every known boson, likewise, and longevity, of Emmy Noether’s theorem is undeniable. D all branches of physics. has an as-yet-unseen fermionic superpartner. The hypothetical supersymmetric particles, which physicists hope Steve Nadis, a contributing editor to Discover and Astronomy, is co-author of to discover at giant particle accelerators like the Large Hadron From the Great Wall to the Great Collider.

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