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Categories: Paleontology: Early Mammals and Birds, Space: The Solar System

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The last population of woolly mammoths was isolated on Wrangel Island off the coast of Siberia 10,000 years ago, when sea levels rose and cut the mountainous island off from the mainland. A new genomic analysis reveals that the isolated mammoths, who lived on the island for the subsequent 6,000 years, originated from at most 8 individuals but grew to 200--300 individuals within 20 generations. The researchers report that the Wrangel Island mammoths' genomes showed signs of inbreeding and low genetic diversity but not to the extent that it can explain their ultimate (and mysterious) extinction.

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Researchers continue to expand the case for the Younger Dryas Impact hypothesis. The idea proposes that a fragmented comet smashed into the Earth's atmosphere 12,800 years ago, causing a widespread climatic shift that, among other things, led to the abrupt reversal of the Earth's warming trend and into an anomalous near-glacial period called the Younger Dryas.

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Early analysis of the asteroid Bennu sample returned by NASA's OSIRIS-REx mission has revealed dust rich in carbon, nitrogen, and organic compounds, all of which are essential components for life as we know it. Dominated by clay minerals, particularly serpentine, the sample mirrors the type of rock found at mid-ocean ridges on Earth. The magnesium-sodium phosphate found in the sample hints that the asteroid could have splintered off from an ancient, small, primitive ocean world.

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Solar physicists have revealed the interior structure of the sun's supergranules, a flow structure that transports heat from the sun's hidden interior to its surface. The researchers' analysis of the supergranules presents a challenge to the current understanding of solar convection.

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If aliens modified a planet in their solar system to make it warmer, we'd be able to tell. A new study identifies the artificial greenhouse gases that would be giveaways of a terraformed planet.

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If liquid water exists today on Mars, it may be too deep underground to detect with traditional methods used on Earth. But listening to earthquakes that occur on Mars -- or marsquakes -- could offer a new tool in the search.

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For the first time, a phenomenon astronomers have long hoped to directly image has been captured by NASA's James Webb Space Telescope's Near-Infrared Camera (NIRCam). In this stunning image of the Serpens Nebula, the discovery lies in the northern area of this young, nearby star-forming region.

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On June 25, China's Chang'e-6 (CE-6) lunar probe is set to return to Earth, carrying the first surface samples collected from the farside of the Moon. In anticipation of this historic event, scientists are publishing their predictions for the unique materials that may be found in the CE-6 samples.

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The history of how stars and galaxies came to be and evolved into the present day remains among the most challenging astrophysical questions to solve yet, but new research brings us closer to understanding it. New insights about young galaxies during the Epoch of Reionization have been revealed. Observations with the James Webb Space Telescope (JWST) of the galaxy Cosmic Gems arc (SPT0615-JD) have confirmed that the light of the galaxy was emitted 460 million years after the big bang. What makes this galaxy unique is that it is magnified through an effect called gravitational lensing, which has not been observed in other galaxies formed during that age.

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Iron meteorites are remnants of the metallic cores of the earliest asteroids in our solar system. Iron meteorites contain refractory metals, such as iridium and platinum, that formed near the sun but were transported to the outer solar system. New research shows that for this to have happened, the protoplanetary disk of our solar system had to have been doughnut-shaped because the refractory metals could not have crossed the large gaps in a target-shaped disk of concentric rings. The paper suggests that the refractory metals moved outward as the protoplanetary disk rapidly expanded, and were trapped in the outer solar system by Jupiter.

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Geologists studied Titan's shorelines and showed through simulations that coastlines of the moon's methane- and ethane-filled seas have likely been shaped by waves. Until now, scientists have found indirect and conflicting signs of wave activity, based on Cassini images of Titan's surface.

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Jupiter's iconic Great Red Spot has persisted for at least 190 years and is likely a different spot from the one observed by the astronomer Giovanni Domenico Cassini in 1665, a new study reports. The Great Red Spot we see today likely formed because of an instability in the planet's intense atmospheric winds, producing a long, persistent atmospheric cell, the study also finds.

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Scientists are rethinking the evolution of vocal learning in birds. New Zealand's smallest bird, the rifleman or titipounamu, may have a rudimentary version of the talent possessed by parrots, hummingbirds and songbirds.

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The small footprint and dim light of white dwarfs, remnants of stars that have burned through their fuel, may make excellent backdrops for studying planets with enough water to harbor life. The trick is spotting the shadow of a planet against a former star that has withered to a fraction of its size and finding that it's a planet that has kept its water oceans for billions of years even after riding out the star's explosive and violent final throes. A new study of the dynamics of white dwarf systems suggests that, in theory, some watery planets may indeed thread the celestial needles necessary to await discovery and closer scrutiny.

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This study discovered mini-Neptunes around four red dwarfs using observations from a global network of ground-based telescopes and the TESS space telescope. These four mini-Neptunes are close to their parent stars, and the three of them are likely to be in eccentric orbits.

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As space travel becomes more frequent, a new biomarker tool was developed by an international team of researchers to help improve the growing field of aerospace medicine and the health of astronauts.

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The structure and function of the kidneys is altered by space flight, with galactic radiation causing permanent damage that would jeopardise any mission to Mars, according to a new study led by researchers from UCL.

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Crater 2, located approximately 380,000 light years from Earth, is one of the largest satellite galaxies of the Milky Way. Extremely cold and with slow-moving stars, Crater 2 has low surface brightness. How this galaxy originated remains unclear. A team of physicists now offers an explanation.

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Astronomers have captured what appears to be a snapshot of a massive collision of giant asteroids in Beta Pictoris, a neighboring star system known for its early age and tumultuous planet-forming activity.

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Astrophysicists calculate the likelihood that Earth was exposed to cold, harsh interstellar clouds, a phenomenon not previously considered in geologic climate models.