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    How the James Webb telescope’s glances back in time are reshaping cosmology

    BALTIMORE — The James Webb Space Telescope is living up to its promise as a wayback machine. The spectacularly sensitive observatory is finding and confirming galaxies more distant, and therefore existing earlier in the universe’s history, than any seen before.

    The telescope, also known as JWST, has confirmed extreme distances to four galaxies, one of which sets a record for cosmic remoteness by shining about 13.475 billion years ago, astronomers reported December 12 at the First Science Results from JWST conference. Dozens of other galaxies may have been spotted as they were just 550 million years or less after the Big Bang, meaning the light from those galaxies traveled at least 13.1 billion years before reaching the telescope.

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    Taken together, the new observations suggest galaxies formed earlier and faster than previously thought. “We’re entering a new era,” says astronomer Swara Ravindranath of the Space Telescope Science Institute in Baltimore.

    That new era is thanks in part to JWST’s ability to see very faint infrared light (SN: 10/6/21). For the most distant objects, like the first stars and galaxies, their visible light is stretched by the relentless expansion of the universe into longer infrared wavelengths that are invisible to human eyes and some previous space telescopes. But now, measurements that were recently impossible are suddenly easy with JWST, researchers say.

    “JWST is the most powerful infrared telescope that has ever been built,” astrophysicist Jane Rigby said at the conference. Rigby, of NASA’s Goddard Space Flight Center in Greenbelt, Md., is the JWST operations project scientist. “Almost across the board, the science performance is better than expected.”

    Even in the very first image, released in July, astronomers spotted galaxies whose light originated 13 billion years ago or more (SN: 7/11/22). But those distances were estimates. To measure the distances precisely, astronomers need spectra, measurements of how much light the galaxies emit across many wavelengths. Those measurements are slower and more difficult to make than pictures.

    “Thanks to this glorious telescope, we’re now getting spectra … for hundreds of galaxies at once,” said astronomer Emma Curtis-Lake of the University of Hertfordshire in England.

    Among those are four of the earliest galaxies ever seen, some of which existed less than 400 million years after the Big Bang, Curtis-Lake and colleagues reported at the meeting and in a paper submitted December 8 to arXiv.org. The team spotted these record holders in a patch of sky that the Hubble Space Telescope once scoured for ultra-remote galaxies (SN: 1/3/10).

    The previous distance record holder existed between 13.3 billion and 13.4 billion years ago, or about 400 million years after the Big Bang (SN: 1/28/20). JWST confirmed the distance to that galaxy and came back with three more whose light comes from as early as 325 million years after the Big Bang.

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    The galaxies are also surprisingly pristine, chemically speaking, lacking in elements heavier than hydrogen and helium.

    “We don’t see that in the present-day universe,” says Ravindranath, who was not involved in the new discovery. It could mean that not many of the galaxies’ stars have died in supernova explosions that spread heavy elements around the universe, which suggests the galaxies’ original stars were not extremely massive.

    In another part of the sky, JWST has spotted 26 galaxies that may have existed about 550 million years or earlier after the Big Bang, astronomer Steven Finkelstein and colleagues reported at the meeting and in a paper submitted November 10 to arXiv.org.

    “On an emotional, visceral level, looking at these images is amazing,” said Finkelstein, of the University of Texas at Austin.

    The first of these to be discovered, dubbed Maisie’s Galaxy after Finkelstein’s daughter, appears to be just 380 million years after the Big Bang, the researchers reported December 1 in the Astrophysical Journal Letters. The most distant galaxy in the team’s survey might lie as much as 130 million years earlier than Maisie. Those galaxies’ distances still need to be confirmed with spectra, but the team expect to get those data in the next few weeks.

    This fuzzy red dot in the inset box at right is Maisie’s Galaxy as seen with JWST. If new measurements of the wavelengths of light it is emitting confirm its distance, astronomers may be seeing this galaxy as it was less than 400 million years after the Big Bang.NASA, STScI, CEERS, TACC, S. Finkelstein, M. Bagley, Z. Levay

    And distant galaxies that lie behind a massive galaxy cluster called Abell 2744 are also more numerous and distant than expected, astrophysicist Guido Roberts-Borsani of UCLA said at the meeting.

    Before JWST observed the cluster, astronomers predicted it should find effectively zero galaxies from 13.2 billion years ago. “But we found two,” said Roberts-Borsani, who reported the results at the meeting. “So something’s a little bit weird.” It could mean that galaxies form earlier and faster than thought, he said, although it could also mean that JWST was just looking at a particularly galaxy-rich patch of the sky.

    All these new galaxies are exciting because they could be responsible for making the universe transparent to visible light, a process astronomers call reionization (SN: 12/2/22). Before the first stars ignited, the universe was filled with a hot dense soup of particles. The first stars and galaxies bathed the universe in ultraviolet light, splitting electrons off hydrogen atoms and allowing light to zip through until it reached JWST.

    The new data, Roberts-Borsani said, “give us constraints on when this process started, ended, and which galaxies were the culprits for this process.” More

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    Read Orris, an exclusive sci-fi short story from Arkady Martine

    In a future where climate change has devastated Florence’s iris fields, a perfumer makes a hard choice in the Hugo award-winning novelist Arkady Martine’s short story

    Humans

    14 December 2022

    By Arkady Martine
    Bekologic
    Elena could give the lecture half-asleep. She’d done it more than once: earbuds shoved in haphazard in the dark and micbead balanced on her sternum, the rest of her cocooned in 30 pounds of weighted blanket. Warm, serene and bodiless. When she needed to do an onboarding for someone in a time zone radically askew to her circadians, she’d even skip VR. The lecture didn’t need an image, just a voice. In Elena’s opinion, it worked better with just a voice. She had the data analytics to prove it, and those data analytics earned her the top end of her salary band. … More

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    This was a terrible year for me, but spending time in nature helped

    My mental health cratered this year after the death of my wife, Clare. Getting out into the natural world has helped me to cope, says Graham Lawton

    Humans

    | Columnist

    14 December 2022

    By Graham Lawton
    Lake Edward in Queen Elizabeth National Park, UgandaRadek Borovka/Shutterstock
    I WON’T mourn the passing of 2022. It has been an annus horribilis for me, my family and our friends. Clare, my life partner of nearly 30 years, wife for 24 of them and mother of my three children, ended her own life in August after enduring a chronic pain syndrome for the best part of a year. I became her carer as her pain spiralled into an abyss of torture. I tried everything I could to save her life, but I failed. … More

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    We have finally found the land of Punt, where pharaohs got their gifts

    The land of Punt, a mysterious place where ancient Egyptians bought gold, incense and other luxury items, has been located using DNA from mummified baboons

    Humans

    14 December 2022

    By Colin Barras
    Antonio Sortino
    WHERE do you find a gift for the pharaoh who has it all? The ancient Egyptians knew: suitably lavish goods were available in Punt. In this mysterious, far-flung land you could obtain all the gold, frankincense and myrrh a pharaoh might desire. To top it off, you could even throw in a baboon or two.
    We have long known of the existence of Punt, a trading partner of the ancient Egyptians that provided them with expensive jewels, spices, ivory and animals. But hieroglyphic texts are frustratingly vague regarding the whereabouts of this extraordinary land, which means the hunt for Punt is one of the unsolved puzzles of Egyptology. Now, finally, we may be zeroing in on an exact location. Surprisingly, the clinching evidence isn’t some newly discovered ancient map. Instead, it comes – quite literally – from the mouth of one of Punt’s baboons.
    The ancient Egyptians first began sailing to Punt about 4500 years ago, visiting the land infrequently for 1300 years. In Punt, the Egyptians could trade their grain, linen and other goods for aromatics, hardwoods and all manner of exotic products that were difficult or impossible to find in Egypt. “Some scholars describe the Egypt-Punt trade relationship as the origin of international peaceful commerce,” says Nathaniel Dominy at Dartmouth College in New Hampshire. “So it’s a big deal.”
    But there is another side to Punt. Consider The Tale of the Shipwrecked Sailor, an approximately 4000-year-old ancient Egyptian text that has been described as the world’s earliest work of fiction. The story tells of a sailor marooned on a fantasy island. There, he meets a gigantic serpent that identifies … More

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    Your gut bacteria may influence how motivated you are to exercise

    A study conducted in mice suggests certain gut bacteria can regulate motivation to exercise by increasing dopamine levels in the brain during physical activity

    Humans

    14 December 2022

    By Grace Wade
    The gut may play a roll in our motivation to exerciseJacob Lund/Alamy
    Motivation to exercise may come from the gut in addition to the brain. A study in mice finds that certain gut bacteria can increase the release of dopamine during physical activity, which helps drive motivation.
    Though most of us know that exercise comes with many benefits, how much people exercise varies widely, says Christoph Thaiss at the University of Pennsylvania. He and his colleagues wanted to identify physiological factors that may explain this variation.
    They collected data from 106 mice on exercise capacity, genetics, gut microbiome composition and more, and fed it to a machine learning model for analysis. The model found that how often mice exercised was most strongly associated with the makeup of their microbiome.Advertisement
    In a series of experiments that followed, the researchers found that mice with depleted gut microbes spent about half as much time voluntarily running on a wheel as those with intact microbiomes. What’s more, they had reduced dopamine levels in their brains during physical activity, suggesting they found exercise less rewarding. The team then repeated these experiments in mice that had intact microbiomes but lacked neurons connecting the gut to the brain and found this resulted in the same effects seen in mice with depleted microbiomes. Together, these findings show the gut plays an integral role in motivation for exercise, Thaiss says.
    The team also identified molecules produced by certain gut bacteria called fatty acid amides that, when given to mice with depleted microbiomes, restored how often they exercised to levels seen in mice with intact microbiomes. “Surprisingly, the motivation for exercise is not brain-intrinsic but is regulated by the gastrointestinal tract,” says Thaiss.
    This isn’t the first time the microbiome has been found to play a role in functions outside our gastrointestinal system. In fact, previous studies have shown that the bacteria in our guts may influence our mood, control blood sugar levels and even protect against inflammation linked to conditions like heart disease and dementia.
    However, it is too early to know if these findings in mice are also true for humans, Thaiss says. He and his team are currently conducting a similar trial in people to see whether we have the same gut-to-brain pathway, and if so, whether leveraging it will boost our motivation to exercise.
    Journal reference: Nature, DOI: 10.1038/s41586-022-05525-z

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    The human brain can be squished 10 times as easily as polystyrene foam

    Researchers used MRI scans and an algorithm to measure the stiffness and resilience to pressure of the brain in living people

    Humans

    14 December 2022

    By Karmela Padavic-Callaghan
    Brains are surprisingly squishyShutterstock/Teeradej
    Though they may look like they are made from rubber, human brains are softer and squishier. Their ability to resist pressure is much less than the polystyrene foam used for packaging, more comparable to that of Jell-O.
    Nicholas Bennion at Cardiff University in the UK and his colleagues set out to develop a method for obtaining more accurate measurements of the brain’s physical properties inside living humans. Most of what we know about how brain tissue reacts to instruments touching it during neurosurgery comes from organs that have been cut into or removed and preserved in chemicals, which can affect tissue stiffness and resilience.
    The researchers performed MRI scans of people lying face down and then face up to shift the location of the brain in the skull. By analysing this data with a machine learning algorithm, they were able to work out different material characteristics of the brain and tissues that connect it to the skull. They quantified how much the brain collapses when pressed on, how it reacts to being pushed sideways and how springy the connective tissues are.Advertisement
    “If you take a brain which hasn’t been preserved in any way, its stiffness is incredibly low, and it breaks apart very easily. And it really is probably a lot softer than most people realise,” says Bennion.
    The team found that brain matter can be compressed up to 10 times as easily as polystyrene foam and that its resilience to being pushed sideways is about a thousandth of what it would be if it were made from rubber – its squishiness is comparable to a slab of Jell-O. Bennion says that the algorithm calculated that the tissues connecting the brain to the skull were also fairly soft, possibly to protect the brain from moving too abruptly.
    Though researchers have long known that brains are very soft and very fragile, the new study makes that notion precise enough to better inform sensitive surgical procedures, says Ellen Kuhl at Stanford University in California.
    The new method, however, may not fully capture the way the brain deforms during motions more violent than shifting positions, such as head trauma in an contact sport or traffic accident, says Krystyn Van Vliet at the Massachusetts Institute of Technology. In these situations, the flow of fluids within the brain can change its material properties.
    The team hopes the model can now be used to predict brain shifts that would occur during surgery for each individual patient based on pre-operative MRI scans. This may eliminate the need for inserting and re-inserting instruments into the brain until they hit the correct spot, making procedures less invasive.
    Journal reference: Journal of the Royal Society Interface, DOI: 10.1098/rsif.2022.0557

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