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Categories: Paleontology: Early Mammals and Birds, Space: Cosmology

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A new analysis of distant galaxies imaged by NASA's James Webb Space Telescope shows that they are extremely young and share some remarkable similarities to 'green peas,' a rare class of small galaxies in our cosmic backyard.

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New images from NASA's James Webb Space Telescope (JWST) reveal galaxies with stellar bars -- elongated features of stars stretching from the centers of galaxies into their outer disks -- at a time when the universe was a mere 25% of its present age. The finding of so-called barred galaxies, similar to our Milky Way, this early in the universe will require astrophysicists to refine their theories of galaxy evolution.

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In giant clusters of hundreds or thousands of galaxies, innumerable stars wander among the galaxies like lost souls, emitting a ghostly haze of light. These stars are not gravitationally tied to any one galaxy in a cluster. The nagging question for astronomers has been: how did the stars get so scattered throughout the cluster in the first place? Several competing theories include the possibility that the stars were stripped out of a cluster's galaxies, or they were tossed around after mergers of galaxies, or they were present early in a cluster's formative years many billions of years ago.

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Orangutans, mice, and horses are covered with it, but humans aren't. Why we have significantly less body hair than most other mammals has long remained a mystery. But a first-of-its-kind comparison of genetic codes from 62 animals is beginning to tell the story of how people -- and other mammals -- lost their locks.

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Microraptor was an opportunistic predator, feeding on fish, birds, lizards -- and now small mammals. The discovery of a rare fossil reveals the creature was a generalist carnivore in the ancient ecosystem of dinosaurs.

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When stars die out, they emit gamma-ray bursts. Although scientist can calculate the explosion energy from dying stars, it is difficult to do when the conversion efficiency is low or unknown. Using light polarization, a research group has found a workaround for this, enabling astronomers to calculate the hidden energy of gamma-ray bursts.

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Astronomers took a 'deep dive' into one of the first images from NASA's James Webb Space Telescope and were rewarded with a surprising discovery: telltale signs of two dozen previously unseen young stars about 7,500 light years from Earth.

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Scientists analyzed new measurements showing that the light emitted by stars outside our galaxy is two to three times brighter than the light from known populations of galaxies, challenging assumptions about the number and environment of stars are in the universe.

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For decades, the Hubble Space Telescope provided us with the most spectacular images of galaxies. This all changed when the James Webb Space Telescope (JWST) launched and successfully completed commissioning. For astronomers, the universe is now revealed in a new way never imagined by the telescope's Near-Infrared Camera (NIRCam) instrument.

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Black holes are surrounded by an invisible layer that swallows every bit of evidence about their past. Researchers are now using machine learning and supercomputers to reconstruct the growth histories of black holes.

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Sediment cores obtained from Eifel maar sites provide insight into the presence of large Ice Age mammals in Central Europe over the past 60,000 years: Overkill hypothesis not confirmed. Herds of megafauna, such as mammoth and bison, have roamed the prehistoric plains in what is today's Central Europe for several tens of thousands of years. As woodland expanded at the end of the last Ice Age, the numbers of these animals declined and by roughly 11,000 years ago, they had completely vanished from this region. Thus, the growth of forests was the main factor that determined the extinction of such megafauna in Central Europe.

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Morphology of galaxies contain important information about the process of galaxy formation and evolution. With its state-of-the-art resolution, NASA's James Webb Space Telescope has now captured several red spiral galaxies in its first image at an unprecedented resolution. Researchers have now analyzed these galaxies, revealing that these are among the furthest known spiral galaxies till date. The analysis further detected a passive red spiral galaxy in the early universe, a surprising discovery.

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While the Diprotodon -- the extinct megafauna species that is distantly related to wombats but was the size of a small car -- is commonly (but incorrectly) thought of as Australia's 'giant wombat', researchers have shed light on a large species that does belong in the modern-day wombat family. The complete skull of this true fossil giant wombat, found in a Rockhampton cave in Queensland, Australia and estimated to be around 80,000 years old, has been described for the first time.

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A study finds that, for now, the catalog of known black hole binaries does not reveal anything fundamental about how black holes form. More data will be needed to determine whether the invisible giants arose from a quiet galactic disk or a more dynamic cluster of stars.

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In a laboratory experiment, researchers have succeeded in realizing an effective spacetime that can be manipulated. In their research on ultracold quantum gases, they were able to simulate an entire family of curved universes to investigate different cosmological scenarios and compare them with the predictions of a quantum field theoretical model.

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Astronomers have discovered the earliest and most distant galaxies confirmed to date using data from the James Webb Space Telescope. The telescope captured light emitted by these galaxies more than 13.4 billion years ago, which means the galaxies date back to less than 400 million years after the Big Bang, when the universe was only 2 percent of its current age.

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Researchers have tested the biting efficiency of Smilodon, an extinct species of carnivore close to the extant felines. Using high-precision 3D scans and simulation methods, the team has just revealed how these animals managed to bite despite the impressive length of their teeth.

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On Dec. 11, 2021, astronomers detected a blast of high-energy light from the outskirts of a galaxy around 1 billion light-years away. The event has rattled scientists' understanding of gamma-ray bursts (GRBs), the most powerful events in the universe.

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Dinosaurs dominated the world right up until a deadly asteroid hit the earth, leading to their mass extinction, some 66 million years ago, a landmark study reveals. Fresh insights into dinosaurs' ecosystems -- the habitats and food types that supported their lives -- suggests that their environments were robust and thriving, right up until that fateful day, at the end of the Cretaceous period.

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Even as detailed images of distant galaxies from the James Webb Space Telescope show us more of the greater universe, scientists still disagree about how life began here on Earth. One hypothesis is that meteorites delivered amino acids -- life's building blocks -- to our planet. Now, researchers have experimentally shown that amino acids could have formed in these early meteorites from reactions driven by gamma rays produced inside the space rocks.