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Categories: Paleontology: Early Mammals and Birds, Space: Astrophysics
Published First ever 3D reconstruction of 52,000-year-old woolly mammoth chromosomes thanks to serendipitously freeze-dried skin
(via sciencedaily.com) Original source An international research team has assembled the genome and 3D chromosomal structures of a 52,000-year-old woolly mammoth -- the first time such a feat has been achieved for any ancient DNA sample. The fossilized chromosomes, which are around a million times longer than most ancient DNA fragments, provide insight into how the mammoth's genome was organized within its living cells and which genes were active within the skin tissue from which the DNA was extracted. This unprecedented level of structural detail was retained because the mammoth underwent freeze-drying shortly after it died, which meant that its DNA was preserved in a glass-like state.
Published Strong evidence for intermediate-mass black hole in Omega Centauri
(via sciencedaily.com) Original source Most known black holes are either extremely massive, like the supermassive black holes that lie at the cores of large galaxies, or relatively lightweight, with a mass of under 100 times that of the Sun. Intermediate-mass black holes (IMBHs) are scarce, however, and are considered rare 'missing links' in black hole evolution.
Published Found with Webb: A potentially habitable icy world
(via sciencedaily.com) Original source A international team of astronomers has made an exciting discovery about the temperate exoplanet LHS 1140 b: it could be a promising 'super-Earth' covered in ice or water.
Published Fresh wind blows from historical supernova
(via sciencedaily.com) Original source A mysterious remnant from a rare type of supernova recorded in 1181 has been explained for the first time. Two white dwarf stars collided, creating a temporary 'guest star,' now labeled supernova (SN) 1181, which was recorded in historical documents in Japan and elsewhere in Asia. However, after the star dimmed, its location and structure remained a mystery until a team pinpointed its location in 2021. Now, through computer modeling and observational analysis, researchers have recreated the structure of the remnant white dwarf, a rare occurrence, explaining its double shock formation. They also discovered that high-speed stellar winds may have started blowing from its surface within just the past 20-30 years. This finding improves our understanding of the diversity of supernova explosions, and highlights the benefits of interdisciplinary research, combining history with modern astronomy to enable new discoveries about our galaxy.
Published Machine learning could aid efforts to answer long-standing astrophysical questions
(via sciencedaily.com) Original source Physicists have developed a computer program incorporating machine learning that could help identify blobs of plasma in outer space known as plasmoids. In a novel twist, the program has been trained using simulated data.
Published Giant salamander-like creature was a top predator in the ice age before the dinosaurs
(via sciencedaily.com) Original source Meet Gaiasia jennyae, the swamp creature with a toilet seat-shaped head. It lived 40 million years before the first dinosaurs, and it was the top predator in its ecosystem.
Published Extinct humans survived on the Tibetan plateau for 160,000 years
(via sciencedaily.com) Original source Bone remains found in a Tibetan cave 3,280 m above sea level indicate an ancient group of humans survived here for many millennia.
Published A new pulsar buried in a mountain of data
(via sciencedaily.com) Original source Astronomers have discovered the first millisecond pulsar in the stellar cluster Glimpse-CO1.
Published The evidence is mounting: humans were responsible for the extinction of large mammals
(via sciencedaily.com) Original source Human hunting, not climate change, played a decisive role in the extinction of large mammals over the last 50,000 years. This conclusion comes from researchers who reviewed over 300 scientific articles from many different fields of research.
Published Tiny bright objects discovered at dawn of universe baffle scientists
(via sciencedaily.com) Original source A recent discovery by NASA's James Webb Space Telescope (JWST) confirmed that luminous, very red objects previously detected in the early universe upend conventional thinking about the origins and evolution of galaxies and their supermassive black holes.
Published Too many missing satellite galaxies found
(via sciencedaily.com) Original source Bringing us one step closer to solving the 'missing satellites problem,' researchers have discovered two new satellite galaxies.
Published The density difference of sub-Neptunes finally deciphered
(via sciencedaily.com) Original source The majority of stars in our galaxy are home to planets. The most abundant are the sub-Neptunes, planets between the size of Earth and Neptune. Calculating their density poses a problem for scientists: depending on the method used to measure their mass, two populations are highlighted, the dense and the less dense. Is this due to an observational bias or the physical existence of two distinct populations of sub-Neptunes? Recent work argues for the latter.
Published Last surviving woolly mammoths were inbred but not doomed to extinction
(via sciencedaily.com) Original source 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.
Published Precision instrument bolsters efforts to find elusive dark energy
(via sciencedaily.com) Original source Dark energy -- a mysterious force pushing the universe apart at an ever-increasing rate -- was discovered 26 years ago, and ever since, scientists have been searching for a new and exotic particle causing the expansion. Physicists combined an optical lattice with an atom interferometer to hold atoms in place for up to 70 seconds -- a record for an atom interferometer -- allowing them to more precisely test for deviations from the accepted theory of gravity that could be caused by dark energy particles such as chameleons or symmetrons. Though they detected no anomalies, they're improving the experiment to perform more sensitive tests of gravity, including whether gravity is quantized.
Published Pillars of creation star in new visualization from NASA's Hubble and Webb telescopes
(via sciencedaily.com) Original source Made famous in 1995 by NASA's Hubble Space Telescope, the Pillars of Creation in the heart of the Eagle Nebula have captured imaginations worldwide with their arresting, ethereal beauty. Now, NASA has released a new 3D visualization of these towering celestial structures using data from NASA's Hubble and James Webb space telescopes. This is the most comprehensive and detailed multiwavelength movie yet of these star-birthing clouds.
Published New evidence for how heat is transported below the sun's surface
(via sciencedaily.com) Original source 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.
Published First of its kind detection made in striking new Webb image
(via sciencedaily.com) Original source 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.
Published A hidden treasure in the Milky Way -- Astronomers uncover ultrabright x-ray source
(via sciencedaily.com) Original source Astronomers uncovered that a well-known X-ray binary, whose exact nature has been a mystery to scientists until now, is actually a hidden ultraluminous X-ray source.
Published Star clusters observed within a galaxy in the early Universe
(via sciencedaily.com) Original source 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.
Published Iron meteorites hint that our infant solar system was more doughnut than dartboard
(via sciencedaily.com) Original source 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.