Philippa Kaur

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    in Space & Astronomy

    A Jupiter-like planet orbiting a white dwarf hints at our solar system’s future

    A glimpse of our solar system’s future has appeared thousands of light-years away in the constellation Sagittarius. There a giant planet like Jupiter orbits a white dwarf, a dim, dense star that once resembled the sun.

    In 2010, that star passed in front of a much more distant star. Like a magnifying glass, the white dwarf’s gravity bent the more distant star’s light rays so that they converged on Earth and made the distant star look hundreds of times brighter. A giant planet orbiting the white dwarf star also “microlensed” the distant star’s light, revealing the planet’s presence.

    In 2015, 2016 and again in 2018 astrophysicist Joshua Blackman of the University of Tasmania in Hobart, Australia and colleagues pointed the Keck II telescope in Hawaii at the far-off system, which lies some 5,000 to 8,000 light-years from Earth. The team was in search of the giant planet’s star, but saw, well, nothing.

    “We expected that we’d see a star similar to the sun,” Blackman says. “And so we spent quite a few years trying to figure out why on Earth we didn’t see the star which we expected to see.”

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    After failing to detect any light from the spot where the planet’s star should be, Blackman’s team concluded that the object can’t be a typical star like the sun — also known as a main sequence star, which generates energy by converting hydrogen into helium at its center. Instead, the star must be something much fainter. The microlensing data indicate that the star is roughly half as massive as the sun, so the object isn’t massive enough to be a neutron star or black hole. But a white dwarf star fits the bill perfectly, the researchers report online October 13 in Nature.

    “They’ve carefully ruled out the other possible lens stars — neutron stars and black holes and main sequence stars and whatnot,” says Ben Zuckerman, an astronomer at UCLA, who was not involved with the work. He notes that only a handful of planets have ever been found orbiting white dwarfs.

    The new planet is the first ever discovered that is orbiting a white dwarf and resembles Jupiter in both its mass and its distance from its star. Blackman’s team estimates that the planet is one to two times as massive as Jupiter and probably lies 2.5 to six times farther from the white dwarf star than Earth does from the sun. For comparison, Jupiter is 5.2 times farther out from the sun than Earth is. The white dwarf is somewhat larger than Earth, which means the planet is much bigger than its host star.

    The white dwarf formed after a sunlike star expanded and became a red giant star. Then the red giant ejected its outer layers, exposing its hot core. That former core is the white dwarf star.

    Our sun will turn into a white dwarf about 7.8 billion years from now, so the new discovery is “a snapshot into the future of our solar system,” Blackman says. As the sun becomes a red giant, it will engulf and destroy its innermost planet, Mercury, and perhaps Venus too. But Mars, Jupiter and more distant planets should survive.

    And Earth? No one yet knows what will happen to it. More

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    in Space & Astronomy

    The fastest-spinning white dwarf ever seen rotates once every 25 seconds

    The sun turns once a month and the Earth once a day, but a white dwarf star 2,000 light-years away spins every 25 seconds, beating the old champ by five seconds. That makes it the fastest-spinning star of any sort ever seen — unless you consider such exotic objects as neutron stars and black holes, some of which spin even faster, to be stars (SN: 3/13/07).  

    About as small as Earth but roughly as massive as the sun, a white dwarf is extremely dense. The star’s surface gravity is so great that if you dropped a pebble from a height of a few feet, it would smash into the surface at thousands of miles per hour. The typical white dwarf takes hours or days to spin.

    The fast-spinning white dwarf, named LAMOST J0240+1952 and located in the constellation Aries, got in a whirl because of its ongoing affair with a red dwarf star that revolves around it. Just as falling water makes a waterwheel turn, so gas falling from the red companion star made the white dwarf twirl.

    The discovery occurred the night of August 7, when astronomer Ingrid Pelisoli of the University of Warwick in Coventry, England, and her colleagues detected a periodic blip of light from the dim duo. The blip repeated every 24.93 seconds, revealing the white dwarf star’s record-breaking rotation period, the researchers report August 26 at arXiv.org.

    The star’s only known rival is an even faster-spinning object in orbit with the blue star HD 49798. But that rapid rotator’s nature is unclear, with some recent studies saying it is likely a neutron star, not a white dwarf. More

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    in Humans

    Ancient seeds reveal we began using tobacco at least 12,300 years ago

    By Carissa Wong

    Modern cultivated tobacco (Nicotiana tabacum) seed vesselsblickwinkel / Alamy
    Seeds discovered at an ancient campsite in Nevada indicate people have been using tobacco for at least 12,300 years, which is far longer than previously thought.
    Tobacco plants are native to North America, and humans are thought to have reached the continent around 20,000 to 16,000 years ago. “This suggests that people learned the intoxicant properties of tobacco relatively early in their time here rather than only with domestication and agriculture thousands of years later,” says Daron Duke at the … More

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    in Humans

    Football teams lost home advantage in lockdowns but it is coming back

    By Luke Taylor

    The roar of the home crowd really does have an impactClive Rose/Getty Images
    It is a long-held belief that football teams playing in their home stadium get a boost from their fans. However, quantifying this effect on match results was difficult until the pandemic created an unprecedented natural experiment when most of the 2020/21 season was played behind closed doors.
    Statistics shared with New Scientist by London-based sports intelligence firm Twenty First Group show that home teams in Europe’s five major men’s football leagues lost a significant home advantage when their games … More

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    in Space & Astronomy

    China’s lunar rock samples show lava flowed on the moon 2 billion years ago

    Lava oozed across the moon’s surface just 2 billion years ago, bits of lunar rocks retrieved by China’s Chang’e-5 mission reveal.

    A chemical analysis of the volcanic rocks confirms that the moon remained volcanically active far longer that its size would suggest possible, researchers report online October 7 in Science.

    Chang’e-5 is the first mission to retrieve lunar rocks and return them to Earth in over 40 years (SN: 12/1/20). An international group of researchers found that the rocks formed 2 billion years ago, around when multicellular life first evolved on Earth. That makes them the youngest moon rocks ever collected, says study coauthor Carolyn Crow, a planetary scientist at the University of Colorado Boulder.  

    The moon formed roughly 4.5 billion years ago. Lunar rocks from the Apollo and Soviet missions of the late 1960s and 70s revealed that volcanism on the moon was commonplace for the first billion or so years of its existence, with flows lasting for millions, if not hundreds of millions, of years.

    Samples of bits of lunar rocks, such as this, are helping scientists study the volcanic evolution of the moon.Beijing SHRIMP Center/Institute of Geology/CAGS

    Given its size, scientist thought that the moon started cooling off around 3 billion years ago, eventually becoming the quiet, inactive neighbor it is today. Yet a dearth of craters in some regions left scientists scratching their heads. Parts of celestial bodies devoid of volcanism accumulate more and more craters over time, in part because there aren’t lava flows depositing new material that hardens into smooth stretches. The moon’s smoother spots seemed to suggest that volcanism had persisted past the moon’s early history.  

    “Young volcanism on a small body like the moon is challenging to explain, because usually small bodies cool fast,” says Juliane Gross, a planetary scientist at Rutgers University in Piscataway, N.J., not involved in the study.

    Scientist had suggested that radioactive elements might offer an explanation for later volcanism. Radioactive decay generates a lot of heat, which is why nuclear reactors are kept in water. Enough radioactive materials in the moon’s mantle, the layer just below the visible crust, would have provided a heat source that could explain younger lava flows.

    To test this theory, the Chang’e-5 lander gathered chunks of basalt — a type of rock that forms from volcanic activity — from a previously unexplored part of the moon thought to be younger than 3 billion years old. The team determined that the rocks formed from lava flows 2 billion years ago, but chemical analysis did not yield the concentration of radioactive elements one would expect if radioactive decay were to explain the volcanism.

    The Chang’e-5 lunar lander extracts samples of the moon that were returned to Earth. The lunar material is the first brought back to Earth in more than 40 years.Chinese National Space Agency’s Lunar Exploration and Space Engineering Center

    This finding is compelling scientists to consider what other forces could have maintained volcanic activity on the moon.

    One theory, says study coauthor Alexander Nemchin, a planetary scientist at the Beijing SHRIMP Center and Curtin University in Bentley, Australia, is that gravitational forces from the Earth could have liquefied the lunar interior, keeping lunar magma flowing for another billion or so years past when it should have stopped.

    “The moon was a lot closer 2 billion years ago,” Nemchin explains. As the moon slowly inched away from the Earth — a slow escape still at work today — these forces would have become less and less powerful until volcanism eventually petered out.

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    Impacts from asteroids and comets also could have kept the moon’s volcanic juices flowing, but “at this point, any guess is a good guess,” says Jessica Barnes, a planetary scientist at the University of Arizona in Tucson not involved in the study.

    “This is a good example of why we need to get to know our closest neighbor,” Barnes says. “A lot people think we already know what’s going on with the moon, but it’s actually quite mysterious.” More

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    in Humans

    Eating to Extinction review: Are our bland diets bad for the world?

    By Gege Li

    The foraging of Hadza honey in Tanzania is under threat due to increasing demand for landKatiekk2/Getty Images
    Book
    Eating to Extinction
    Dan SaladinoAdvertisement

    OUR diets are more homogenous than at any other point in human history, says food journalist Dan Saladino. Particularly in the West, a revolution in farming methods since the second world war has led us to a point where much of what we eat comes from just a few established varieties of crops and animals, controlled by a handful of companies.
    This has undoubtedly had many benefits for humanity, making food supplies more predictable, cheaper and more accessible, and helping to curb malnutrition. Yet in his new book, Eating to Extinction: The world’s rarest foods and why we need to save them, Saladino argues that it has also pushed thousands of little-known foods, many with beneficial characteristics or rich historical and cultural significance, to the brink of extinction.
    “The human diet has undergone more change in the last 150 years (roughly six generations) than in the previous one million years (around 40,000 generations),” he writes. This is worrisome, because restricting ourselves to such a narrow range of varieties diminishes the genetic variation that might protect crops and livestock from disease.
    It also narrows the diversity of our gut microbiome, which is vital for our health and well-being, and risks the loss of entire culinary traditions forever. As Saladino puts it, “where nature creates diversity, the food system crushes it”.
    Through a narrative that weaves science and history with stories spanning every corner of the globe, Saladino makes an urgent call to protect the world’s rare foods. The alternative, he warns, is a future where we lose our grip on nature and the vital services it provides, perhaps permanently.
    The book is split into 10 parts, each focusing on a different category: wild foods (hunted or foraged); cereals; vegetables; meat; fish and seafood; fruit; cheese; alcohol; stimulants (tea and coffee) and sweet foods. In every chapter, Saladino highlights a few ingredients and traces their origins, meeting the people who are championing food biodiversity. Often, these individuals represent the last line of defence between a food and its extinction.
    Saladino covers so much ground that it is hard to touch on even a fraction of the foods he explores. Just one example of a rare food with a remarkable story to tell is Hadza honey, foraged by some of the few remaining hunter-gatherer societies – the Hadza people of Tanzania.
    Through a relationship forged over millennia, the Hadza have learned to work together with honeyguide birds so both can reap the rewards of the nutritious honey found high in baobab trees.
    But this special dynamic is under threat: the rising demand for land for crops and livestock is spilling into Hadza territory, putting their livelihoods at risk and depleting the supply of honey and other wild foods on which they depend. Saladino makes the impact of these potential losses clear, often rounding off a chapter with a moving story that underscores how tragic it would be if these foods ceased to exist.
    Packed full of knowledge about a host of ingredients that you probably didn’t even know existed, Eating to Extinction captures the urgency (and cost) of heading towards a future that is less nutritionally diverse.
    “We cannot afford to carry on growing crops and producing food in ways that are so violently in conflict with nature; we can’t continue to beat the planet into submission, to control, dominate and all too often destroy ecosystems,” Saladino concludes. “The endangered foods in this book helped make us who we are; they could be foods that show us who we become.”

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    in Humans

    The Apollo Murders review: Chris Hadfield's novel is a space thriller

    By Jacob Aron

    Home feels a long way away when you don’t know who to trustFabio Formaggio/EyeEm/Getty Images
    Book
    The Apollo Murders
    Chris Hadfield QuercusAdvertisement

    I FOLLOW space flight pretty closely, and yet I couldn’t tell you the names of the people currently aboard the International Space Station (ISS) without looking it up.
    We weren’t always this blasé about human space flight. In the early days of crewed missions, NASA’s Mercury Seven astronauts were magazine cover stars and celebrities. In the 21st century, though, most astronauts are completely anonymous.
    Chris Hadfield, the Canadian former commander of the ISS, is a rare exception. He first flew to space in 1995, riding on NASA’s space shuttle to visit the Russian space station Mir. He came to public prominence much later, in 2013, during his third and final mission to orbit, when he used social media including Twitter and YouTube to swap messages with the likes of William Shatner and talk about life onboard the station.
    All of this culminated with Hadfield releasing a cover of David Bowie’s Space Oddity, recorded in microgravity. The video has since been viewed more than 50 million times, and is still as awe-inspiring as ever. While on the ISS, Hadfield made space seem exciting and relevant to the average person in a way that it hadn’t been for many years. “Space flight isn’t just about doing experiments, it’s about an extension of human culture,” he told me when we spoke following his return to Earth.
    Since retiring from the Canadian Space Agency, Hadfield has written a number of non-fiction books, including his autobiography, An Astronaut’s Guide to Life on Earth. Now, he has turned his hand to thrillers with The Apollo Murders, an alt-history set during the cold war that seemingly draws on his own space flight experiences and takes them to dramatic extremes.
    The story unfolds in an alternative version of 1973, when a new kind of space race quickly gets ugly as both the USSR and the US are hoping to exploit an unusual find on the surface of the moon. Hadfield’s version of 1973 has two key differences from our own. First, the Apollo 18 moon mission was redesignated to be a military operation run by the US Air Force, rather than being cancelled along with Apollo 19 and 20 following the failure of Apollo 13, as happened in reality.
    Second, the Soviet Union’s first attempt at launching an Almaz military space station was successful. The real version burned up in Earth’s atmosphere after failing to reach a stable orbit, though a second attempt succeeded in 1974.
    These two historical tweaks set the stage for the first military encounter in space – an event that thankfully has never happened in the real world. Old rivalries between the nations play out alongside personal grudges and a rising uncertainty about who to trust. The fact that back-up is almost 400,000 kilometres away only adds to the tension. It also allows Hadfield to unleash his inner Tom Clancy to great effect.
    As someone who has actually been to space, Hadfield makes his techno-thiller jargon read true, whether it is the details of managing air pressure changes during a rocket launch or the blow-by-blow mechanics of hand-to-hand combat in microgravity.
    “The story is improbable but not implausible. Hadfield only includes events that could have actually happened”
    Overall, the story comes across as improbable but not implausible. Hadfield is careful to only include events that could have actually happened. In this respect, there are echoes of the excellent Apple TV+ series For All Mankind, which also deals with an alt-history space conflict. While reading, I did wonder if Hadfield had been watching the series and taking notes – the book was written during lockdown in the covid-19 pandemic, so perhaps he had time on his hands.
    Either way, I wouldn’t be surprised to see The Apollo Murders get its own turn on the screen, because it seems ripe for adaptation as a film or TV series.
    If I have one quibble, it is with the way that Hadfield has written some of the dialogue between Soviet characters. Scenes with Russian speakers that take place in the USSR are written in plain English, but when they encounter people from the US, the writing switches to transliterated Cyrillic, which is then repeated in English, to grating effect.
    Still, it is a minor point for what is otherwise an accomplished story from a first-time novelist. Hadfield leaves the door open for potential sequels in this universe, and I am keen to see what he does next.

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    in Humans

    Living Proof review: A unique take on Scotland's environmental history

    By Simon Ings

    National Library of Scotland
    Film
    Living Proof: A climate story Emily Munro
    Online nowAdvertisement

    An era-defining investigation of how growth occurs in nature and society, from tiny organisms to empires and civilisations, exploring the pitfalls of the drive to go big.
    MOST environmental documentaries concentrate on the environment. Most films about climate change focus on people tackling the crisis. Living Proof, assembled and edited by Emily Munro, a curator of the moving image at the National Library of Scotland, is different.
    It is a film about working people and their employers, about people whose day-to-day actions have contributed to Scotland’s industrialisation, its export of materials and methods (particularly in the field of offshore oil and gas) and the associated environmental impact.
    Collated from an array of public information films and promotional videos from the 1940s onwards, and set to a contemporary soundtrack, Living Proof is an archival history of what Scotland has told itself about itself. It also explores the local and global repercussions of those stories, ambitions and visions.
    Munro is in thrall to the changing Scottish industrial landscape, from its herring fisheries to its dams, from its slums and derelict mine-heads to the high modernism of its motorways and strip malls.
    Living Proof is also – and this is more important – a film that respects its subjects’ changing aspirations. It tells the story of a nation that is trying to do right by its people.
    It will come as no surprise, as Glasgow prepares to host the COP26 global climate conference, to hear that the consequences of those efforts haven’t been uniformly good. Powered by offshore oil and gas, and a redundancy-haunted grave for a dozen heavy industries, from coal mining and shipbuilding to steel manufacture, Scotland has a somewhat chequered environmental history.
    “Much harm has been done to the planet in the name of doing what is best for the people”
    As Munro’s film shows, however, the environment has always been a central plank of arguments both for and against industrial development in Scotland. The idea that people in Scotland (and elsewhere) have only now considered the environment is nonsense.
    Only towards the end of Munro’s film do we meet protesters of any kind, deploring the construction in 1980 of a nuclear power plant at Torness, about 50 kilometres east of Edinburgh. Munro is less interested in the protest itself than in one impassioned speech that completes the argument begun in the first reel (via a public information film from the mid-1940s): that much harm has been done to the planet in the name of what is best for the people who depend on it, both as a home and a source of income.
    This, indeed, is where we began: with a vision of a nation that, if it cannot support its own people, will go to rack and ruin, with (to quote that 1943 information film) “only the old people and a few children left in the glen”.
    Living Proof critiques an economic system that, whatever its promises, cannot help but denude the planet of its resources, often at the expense of its people. It is all the more powerful for being articulated through real things: schools and pharmaceuticals, earth movers and oil rigs, washing machines and gas boilers.
    Reasonable aspirations have done unreasonable harm to the planet. That is the real crisis elucidated by Living Proof. It is a point too easily lost in all the shouting. And it has rarely been made so well.
    Simon also recommends…
    Film
    Bodysong
    Simon Pummell
    This BAFTA award-winning documentary about the human condition is woven from a dizzying array of archive resources.
    Book
    Growth
    Vaclav Smil

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