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    Vera Rubin’s work on dark matter led to a paradigm shift in cosmology

    Bright Galaxies, Dark Matter, and BeyondAshley Jean YeagerMIT Press, $24.95

    Vera Rubin’s research forced cosmologists to radically reimagine the cosmos.

    In the 1960s and ’70s, Rubin’s observations of stars whirling around within galaxies revealed the gravitational tug of invisible “dark matter.” Although astronomers had detected hints of this enigmatic substance for decades, Rubin’s data helped finally convince a skeptical scientific community that dark matter exists (SN: 1/10/20).

    “Her work was pivotal to redefining the composition of our cosmos,” Ashley Yeager, Science News’ associate news editor, writes in her new book. Bright Galaxies, Dark Matter, and Beyond follows Rubin’s journey from stargazing child to preeminent astronomer and fierce advocate for women in science.

    That journey, Yeager shows, was rife with obstacles. When Rubin was a young astronomer in the 1950s and ’60s, many observatories were closed to women, and more established scientists often brushed her off. Much of her early work was met with intense skepticism, but that only made Rubin, who died in 2016 at age 88, a more dogged data collector.

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    On graphs plotting the speeds of stars swirling around galaxies, Rubin showed that stars farther from galactic centers orbited just as fast as inner stars. That is, the galaxies’ rotation curves were flat. Such speedy outer stars must be pulled along by the gravitational grip of dark matter.

    Science News staff writer Maria Temming spoke with Yeager about Rubin’s legacy and what, beyond her pioneering research, made Rubin remarkable. The following discussion has been edited for clarity and brevity.

    Temming: What inspired you to tell Rubin’s story?

    Yeager: It all started when I was working at the National Air and Space Museum in Washington, D.C., in 2007. I was walking around the “Explore the Universe” exhibit and noticed there weren’t many women featured. But then there was this picture of a woman with big glasses and cropped hair, and I thought, “Who is this?” It was Vera Rubin.

    My supervisor was a curator of oral histories. He was working on Rubin’s, so I asked him about her. He said, “I have one more oral history interview to do with her. Would you like to come?” So I got to interview her. She was charismatic, kind and curious — not a person who was all about herself, but wanted to know about you. That stuck with me.

    Temming: You spend much of the book describing evidence for dark matter besides Rubin’s research. Why?

    Yeager: I wanted to make sure I didn’t portray Rubin as this lone person who discovered dark matter, because there were a lot of different moving pieces in astronomy and physics that came together in the ’70s and early ’80s for the scientific community to say, “OK, we really have to take dark matter seriously.”

    Temming: What made Rubin’s work a linchpin for confirming dark matter?

    Yeager: She really went after nailing down that flat rotation curve in all types of galaxies. Mainly because she did get a lot of pushback, continually, that said, “Oh, that’s just a special case in that galaxy, or that’s just for those types of galaxies.” She studied hundreds of galaxies to double-check that, yes, in fact, the rotation curves are flat. People saying, “We don’t believe you,” didn’t ever really knock her down. She just came back swinging harder.

    It helped that she did the work in visible wavelengths of light. There had been a lot of radio astronomy data to suggest flat rotation curves, but because radio astronomy was very new, it was really only once you saw it with the eye that the astronomy community was convinced.

    Temming: Do you have a favorite anecdote about Rubin?

    Yeager: The one that comes to mind is how much she loved flowers. She told me about how on drives from Lowell Observatory to Kitt Peak National Observatory in Arizona, she and her colleague Kent Ford would always stop and buy wildflowers. The fact that picking these wildflowers stuck with her, I thought, was just representative of who she was. Her favorite moments weren’t necessarily these big discoveries she’d made, but stopping to pick some flowers and enjoy their beauty.

    Author Ashley Yeager (left) interviewed Vera Rubin (right) in 2007 as part of an oral history project with Smithsonian’s National Air and Space Museum.Smithsonian National Air and Space Museum (NASM 9A16674)

    Temming: Did you learn anything in your research that surprised you?

    Yeager: I didn’t initially grasp how many different types of projects she had. She did a lot with looking for larger-scale structure [in the universe] and looking at the Hubble constant [which describes how fast the universe is expanding] (SN: 4/21/21). She had a very diverse set of questions that she wanted to answer, well into her 70s.

    Temming: I was surprised by her decision to get out of the rat-race of hunting for quasars, when that area of research heated up in the 1960s.

    Yeager: She very much didn’t like to be in pressure situations where she could be wrong. She liked to go and collect so much data that no one could [dispute it]. With quasar research, it was just too fast, and she wanted to be methodical about it.

    Temming: Why is Rubin’s story important to tell now?

    Yeager: Unfortunately for women and minorities in science, it’s still very relevant, in that there are a lot of challenges to pursuing a career in STEM. Her story demonstrates that you have to surround yourself with people who are willing to help you and get away from the people who want to keep you down. Plus her story is also very encouraging: Your curiosity can keep you going and can fuel something way bigger than yourself.

    Temming: How did she advocate for women in astronomy?

    Yeager: She was very outspoken about it. At National Academy of Sciences meetings, the organizers always dreaded her standing up, because she would say, “What are we doing about women in science? We’re not doing enough.” She was constantly pushing for women to be recognized with awards. She kept tabs on the number of women who had earned Ph.D.s and who had gotten staff positions — and their salaries. She was very data-driven. She’d cull that information and use it to advocate for better representation and recognition of women in astronomy.

    Temming: How would you describe Rubin to someone who hasn’t met her?

    Yeager: She was one of the most persistent, gracious and nurturing people that I’ve ever met. You could strip away all that she did in astronomy and she would still be this incredible figure — the way she carried herself, the way she treated people. Just a beautiful human being.

    Buy Bright Galaxies, Dark Matter, and Beyond from Bookshop.org. Science News is a Bookshop.org affiliate and will earn a commission on purchases made from links in this article. More

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    Ancient dog faeces show how our canine friends became omnivores

    By James Urquhart

    Dog food often contains grains – and may have done so for thousands of yearsJaromir Chalabala / Alamy Stock Photo
    Dog diets often contain more starch than those of their carnivorous wolf ancestors, and an analysis of fossilised dog faeces helps explain how the animals made the dietary change. Long before their genomes adapted to their plant-rich chow, their gut microbiome gained a starch-digesting profile.
    Due to their close association with humans, it is thought that dogs’ diets shifted to less meat and more carbohydrates when farming began – an idea that was supported by an archaeological analysis … More

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    Measuring a black hole’s mass isn’t easy. A new technique could change that

    An actively feeding black hole surrounds itself with a disk of hot gas and dust that flickers like a campfire. Astronomers have now found that monitoring changes in those flickers can reveal something that is notoriously hard to measure: the behemoth’s heft.

    “It’s a new way to weigh black holes,” says astronomer Colin Burke of the University of Illinois at Urbana-Champaign. What’s more, the method could be used on any astrophysical object with an accretion disk, and may even help find elusive midsize black holes, researchers report in the Aug. 13 Science.

    It’s not easy to measure a black hole’s mass. For one thing, the dark behemoths are notoriously difficult to see. But sometimes black holes reveal themselves when they eat. As gas and dust falls into a black hole, the material organizes into a disk that is heated to white-hot temperatures and can, in some cases, outshine all the stars in the galaxy combined.

    Measuring the black hole’s diameter can reveal its mass using Einstein’s general theory of relativity. But only the globe-spanning Event Horizon Telescope has made this sort of measurement, and for only one black hole so far (SN: 4/22/19). Other black holes have been weighed via observations of their influence on the material around them, but that takes a lot of data and doesn’t work for every supermassive black hole.

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    So, looking for another way, Burke and colleagues turned to accretion disks. Astronomers aren’t sure how black holes’ disks flicker, but it seems like small changes in light combine to brighten or dim the entire disk over a given span of time. Previous research had hinted that the time it takes a disk to fade, brighten and fade again is related to the mass of its central black hole. But those claims were controversial, and didn’t cover the full range of black hole masses, Burke says.

    So he and colleagues assembled observations of 67 actively feeding black holes with known masses. The behemoths spanned sizes from 10,000 to 10 billion solar masses. For the smallest of these black holes, the flickers changed on timescales of hours to weeks. Supermassive black holes with masses between 100 million and 10 billion solar masses flickered more slowly, every few hundred days.

    “That gives us a hint that, okay, if this relation holds for small supermassive black holes and big ones, maybe it’s sort of a universal feature,” Burke says.

    Out of curiosity, the team also looked at white dwarfs, the compact corpses of stars like the sun, which are some of the smallest objects to sport consistent accretion disks. Those white dwarfs followed the same relationship between flicker speed and mass.

    The analyzed black holes didn’t cover the entire possible range of masses. Known black holes that are from about 100 to 100,000 times the mass of the sun are rare. There are several potential candidates, but only one has been confirmed (SN: 9/2/20). In the future, the relationship between disk flickers and black hole mass could tell astronomers exactly what kind of disk flickers to look for to help bring these midsize beasts out of hiding, if they’re there to be found, Burke says.

    Astrophysicist Vivienne Baldassare of Washington State University in Pullman studies black holes in dwarf galaxies, which may preserve some of the properties of ancient black holes that formed in the early universe. One of the biggest challenges in her work is measuring black hole masses. The study’s “super exciting results … will have a large impact for my research, and I expect many others as well,” she says.

    The method offers a simpler way to weigh black holes than any previous technique, Burke says — but not necessarily a faster one. More massive black holes, for example, would need hundreds of days, or possibly years, of observations to reveal their masses.

    Upcoming observatories are already planning to take that kind of data. The Vera C. Rubin Observatory is expected to start observing the entire sky every night beginning in 2022 or 2023 (SN: 1/10/20). Once the telescope has been running long enough, the observations needed to weigh black holes “will fall out for free” from the Rubin Observatory data, Burke says. “We’re already building it. We may as well do this.” More

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    I'm Your Man review: How to fall in love with a robot – maybe

    By Jon O’Brien

    Alma and Tom gradually become closer in this offbeat love storyChristine Fenzl
    Film
    I’m Your Man
    Maria SchraderAdvertisement

    CAN happiness flourish even when it is knowingly built on fabrication? Is perfection conducive to a healthy partnership? Can artificial and emotional intelligence truly coexist? Fresh from her Emmy-winning success with the Netflix miniseries Unorthodox, Maria Schrader leaves such questions hanging in I’m Your Man, her fourth film.
    Adapted from Emma Braslavsky’s short story Ich bin dein Mensch, this German-language tale stars Downton Abbey‘s Dan Stevens as Tom, the ideal life partner. He is a handsome sharp-dresser with blue eyes that could pierce a stone, a penchant for romantic gestures and a willingness to cater to every whim. He is also a humanoid robot.
    Love in the time of algorithms has been explored in the Amazon anthology Soulmates and Netflix’s Osmosis and The One. However, the central coupling here is born out of necessity rather than a search for “the one”.
    Academic Alma (Maren Eggert) has reluctantly agreed to house Tom in a three-week experiment, which will help finance her research. She is completely uninterested in sharing a bed, or even a conversation, with this apparent kindred spirit, created to make her happy. “Leaving me alone should be no problem at all,” she tells Tom, who can’t compute her disdain. “That’s what makes me happiest.”
    I’m Your Man is a curiosity. You could call it a sci-fi rom, yet there is little if any sci-fi or, indeed, rom. The tech behind Tom comes into play just once when he briefly malfunctions, while the film’s Berlin setting is a near-future whose aesthetic is more soft pastels than dark dystopia.
    Despite Tom’s best efforts to ignite a spark using the millions of data strands at his disposal, he is thwarted by a dismissive Alma at every turn. “Ninety-three per cent of German women dream of this,” he remarks, after running a candlelit bath, strewn with rose petals. “Guess which group I belong to,” comes the reply.
    It is only when Tom tones down the programmed cliches and starts responding less, well, robotically that the iciness thaws. He senses the sadness behind Alma’s steely exterior, and his matter-of-fact, yet effective, probing renders their “couples counsellor” (Toni Erdmann‘s Sandra Hüller) obsolete. Before long, Alma surprises herself by defending Tom from a colleague with no sense of personal space.
    If I’m Your Man had emerged from Hollywood, this would be the cue for wedding bells. But European arthouse tends to avoid wrapping things up neatly in a bow. Although she slowly succumbs to Tom’s attributes, both physical and mental, Alma always remains aware that she is being manipulated by his constant recalibration. Happily-ever-after never looks likely.
    Still, the two stars ensure you remain invested in this relationship, wherever it leads. Eggert offsets Alma’s abrasiveness with a quiet vulnerability and compassion, particularly in the scenes with her cranky dad (Wolfgang Hübsch) who has dementia, which hint at her fear of ending up in a lonely state, too.
    Meanwhile, Stevens is charm personified in a performance partly inspired by Cary Grant. His comic timing is exquisite, proving that his scene-stealing turn in last year’s Eurovision movie was no fluke.
    Schrader has served up a new, if resolutely low-key, tragi-comic spin on the digital love story that combines depth, humour and, no matter how mechanical, heart.

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    The surprising ways the place where you work affects your performance

    Your brain is exquisitely sensitive to your surroundings, tuning into external cues and distractions whether you like it or not. Understanding how this happens could change the way we work

    Humans

    11 August 2021

    By Annie Murphy Paul

    Objects we place in our workspace reinforce our sense of identityMelanie Acevedo/trunkarchive.com
    IN THE summer of 2001, Sapna Cheryan was a new graduate interviewing for internships at tech firms in California’s Bay Area. At one company, she recalls, the workspace looked like a computer enthusiast’s basement hang-out, full of action figures and Nerf guns, with a soda-can model of the Golden Gate Bridge. To her, it seemed designed to promote an exclusive conception of the firm’s ideal employee. As a young woman of colour, she felt unwelcome, even alienated. She accepted a place at another company – one with a workspace that was bright and inviting.
    Five years later, Cheryan’s next move was to Stanford University in California to start a PhD investigating how physical cues in our environment affect how we think and feel. She is among a growing number of psychologists and cognitive scientists whose research challenges the idea that the brain is like a computer. Computers are indifferent to their surroundings: a laptop works the same in a fluorescent-lit office or a leafy park. The same isn’t true of the human brain. In fact, Cheryan and others have found its performance to be exquisitely sensitive to the context in which it operates.
    This research seems especially relevant right now. During the pandemic, many of us were abruptly forced to work and learn in different surroundings, and the effect of place on cognition came into sharp focus. As some of us return to offices and schools, we have an opportunity to reimagine these spaces in accordance with what researchers have … More

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    Why are so many records being broken at the Tokyo Olympics?

    Michelle Durbano
    THE Tokyo Olympics have brought some of the fastest times ever seen on the athletics track. At an astonishing number of races, athletes are beating personal bests along with national, Olympic and world records. Elaine Thompson-Herah set a new Olympic record in the women’s 100 metres, breaking Florence Griffith Joyner’s record set over 33 years ago. World records were smashed in both the men’s and women’s 400 metres hurdles, by Karsten Warholm and Sydney McLaughlin respectively. In both these events, the silver medallist also ran faster than the previous world record.
    Is this just an unusually good Olympics for record-breaking races or is something different going on? Part of the answer can be found by looking down at an athlete’s feet.
    If you look closely, you might spot some new technology known as “super spikes” – and underfoot, there is a high-tech track.Advertisement
    Recently, track spikes – shoes that have spikes on the underside to give runners grip – have seen a similar shift in the performance-enhancing technology that previously took over marathon racing shoes. Marathon “super shoes” first emerged in 2017 with Nike’s Vaporfly 4%, which gave athletes average energy savings of 4 per cent compared with competitors not wearing them. By now, almost every brand has a super shoe, and the new technology is being applied to track spikes.
    Similar to their super shoe counterparts, super spikes combine soft, compliant and resilient foam with a stiff, curved carbon-fibre plate. The exact benefits of super spikes are difficult to quantify, but each component probably plays a role.

    Traditionally, track spikes have tried to lessen the amount of midsole foam to reduce weight and energy absorption. However, new technology is lightweight and the foam is better at returning energy to the athlete than foams before it, giving back as much as 80 to 90 per cent. In this way, the foam acts as a spring with each step the athlete takes.
    The role of the carbon-fibre plate is less clear. Research has shown that stiffening track spikes will reduce the amount of energy lost during toe flexion. This may increase the demands on the ankle. However, it has also been shown that if an athlete is strong enough to meet these increased demands, the plate allows them to get a more effective push off.
    Another new technology contributing to athletes’ speed in Tokyo is the track. While it may look like a regular track, Mondo, the company behind it, spent three years researching and developing the surface specifically for Tokyo 2020. The track has been precisely tuned to allow shock absorption and energy return, playing a similar role to the foam in spikes.
    Research on engineered track surfaces is as old as 1978, when it was found that a compliant, resilient track surface could improve times by as much as 2.9 per cent. Although the exact savings of the Tokyo track are unknown, its developers have said it could improve times by as much as 2 per cent compared with previous Olympic tracks.
    While it is tempting to attribute the record-breaking times to the new spike and track technologies alone, other factors are at play too. The games being delayed by a year due to the covid-19 pandemic may actually have benefited some athletes, giving them more time to train. Other, more variable, factors, such as the weather, can affect how an athlete performs on any given day. And above all, we cannot ignore the effort and talent of the athletes competing in these races. It may just be that we have got a particularly talented crop this year.
    Overall, the record-breaking times seen in Tokyo are likely to be a combination of all the above, including fast shoes, fast tracks and extremely talented athletes. ❚
    Laura Healey is a manager of footwear innovation at Puma 

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    Both boys and girls tend to write stories about boys

    By Jason Arunn Murugesu

    School children in the UK tend to place male characters in the stories they writemartin-dm/Getty Images
    Stories written by children are far more likely to feature male characters – regardless of whether the writer is a boy or a girl.
    Yaling Hsiao at the University of Oxford and her colleagues analysed more than 100,000 short stories written by British children, aged 5 to 13, for a national writing competition organised by the BBC in 2019.
    The researchers wanted to find out how a child’s gender influenced the gender of the characters … More

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    After Yang review: A delightful movie about robots teaching humans

    By Davide Abbatescianni

    Jake (Colin Farrell) is taught important life lessons by an android in After YangA24 FILMS
    After Yang
    Kogonada
    Distribution pendingAdvertisement
    MANY great works of art have depicted complex relationships between humans and androids, and how their interactions could shake up how we see society and its constructs. Take Steven Spielberg’s movie A.I. Artificial Intelligence, Isaac Asimov’s seminal novel I, Robot or even David Cage’s recent video game Detroit: Become Human. Now there is After Yang, from director Kogonada.
    The movie, which premiered at the Cannes Film Festival last month, is based on Alexander Weinstein’s short story Saying Goodbye to Yang. It follows tea seller Jake (Colin Farrell) and his wife Kyra (Jodie Turner-Smith), who have bought an android named Yang (Justin H. Min) for their adopted daughter Mika (newcomer Malea Emma Tjandrawidjaja).
    Their hope is that Yang, who resembles a teenager, will help Mika reconnect with her roots in China. After a few days, the android stops working and Jake must find a way to reactivate him. Yang, however, is a refurbished “technosapien”, so the seller can only offer Jake a discount on his next purchase or to destroy Yang for a fee.
    Mika has already developed a connection with the android and Jake doesn’t want to disappoint her. Through different repair attempts and an encounter with a technosapiens museum curator, Cleo (Sarita Choudhury), Jake delves into his own past as well as Yang’s. In the process, he starts to question the way he sees organic and synthetic life, gradually discovering that Yang is capable, like “real” humans, of loving, remembering and appreciating the taste of a good cup of tea.
    Thanks to the elegant production design, the future depicted by Kogonada is a visual feast, loosely echoing the world evoked in Spike Jonze’s Her. Here, advanced technology and environmental awareness seem to coexist within a heavily urbanised, multicultural society. It is a place where androids and humans can live together peacefully, or at least tolerate each other’s presence.
    Throughout the film, Kogonada builds a strong bond between the family and Yang. Yes, Yang is a machine programmed to feel and express emotions, but what makes him human (or at least “organic”) are his memories, which let him develop an identity and learn from other people’s emotions and experiences.
    Yang’s life with Jake’s family is meaningful: his presence and (spoiler alert) subsequent demise force the family to go through an unexpected crisis, but also help them heal deeper wounds, with Jake and Kyra coming to realise that they are the only ones who can really be in charge of Mika’s future and how she reconnects to her Chinese roots.
    The cast – Farrell and Turner-Smith, in particular – deliver understated performances, which suit the intimate atmosphere of this tale. Skilfully combining elements of family drama and science fiction with elegant tributes to Japanese director YasujirŌ Ozu, Kogonada creates a compelling, quasi-philosophical piece about the mystery of the soul. The movie could have ended before the final exchange between Jake and Mika, but never mind, it’s still enchanting.
    If you are hungry for similar fare, try Kazuo Ishiguro’s recent novel Klara and the Sun, a darker world where children are genetically engineered to achieve academically and are homeschooled by solar-powered AIs.

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