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Categories: Paleontology: Early Mammals and Birds, Space: Cosmology
Published Astrophysicists propose a new way of measuring cosmic expansion: Lensed gravitational waves
(via sciencedaily.com) Original source The universe is expanding; we've had evidence of that for about a century. But just how quickly celestial objects are receding from each other is still up for debate.
Published First 'ghost particle' image of Milky Way
(via sciencedaily.com) Original source Scientists have revealed a uniquely different image of our galaxy by determining the galactic origin of thousands of neutrinos -- invisible 'ghost particles' which exist in great quantities but normally pass straight through Earth undetected. The neutrino-based image of the Milky Way is the first of its kind: a galactic portrait made with particles of matter rather than electromagnetic energy.
Published Earliest strands of the cosmic web
(via sciencedaily.com) Original source Galaxies are not scattered randomly across the universe. They gather together not only into clusters, but into vast interconnected filamentary structures with gigantic barren voids in between. This 'cosmic web' started out tenuous and became more distinct over time as gravity drew matter together.
Published Gravitational waves from colossal black holes found using 'cosmic clocks'
(via sciencedaily.com) Original source You can't see or feel it, but everything around you -- including your own body -- is slowly shrinking and expanding. It's the weird, spacetime-warping effect of gravitational waves passing through our galaxy. New results are the first evidence of the gravitational wave background -- a sort of soup of spacetime distortions pervading the entire universe and long predicted to exist by scientists.
Published Starlight and the first black holes: researchers detect the host galaxies of quasars in the early universe
(via sciencedaily.com) Original source For the first time, the James Webb Space Telescope has revealed starlight from two massive galaxies hosting actively growing black holes -- quasars -- seen less than a billion years after the Big Bang.
Published A jaw-dropping conundrum: Why do mammals have a stiff lower jaw?
(via sciencedaily.com) Original source The lower jaws of lizards, birds, fish and even dinosaurs are comprised of multiple bones per side. Yet mammals diverged from all other vertebrates and settled on just one bone, repurposing the extra bones into a more elaborate inner ear, perhaps the better to hear. The single bone per side, fused in primates into one jawbone, makes the jaw more rigid. A paleontologist asks, Did the stiffer, rigid jaw make mammals more successful?
Published Humans' ancestors survived the asteroid impact that killed the dinosaurs
(via sciencedaily.com) Original source A Cretaceous origin for placental mammals, the group that includes humans, dogs and bats, has been revealed by in-depth analysis of the fossil record, showing they co-existed with dinosaurs for a short time before the dinosaurs went extinct.
Published Megalodon was no cold-blooded killer
(via sciencedaily.com) Original source How the megalodon, a shark that went extinct 3.6 million years ago, stayed warm was a matter of speculation among scientists. Using an analysis of tooth fossils from the megalodon and other sharks of the same period, a study suggests the animal was able to maintain a body temperature well above the temperature of the water in which it lived. The finding could help explain why the megalodon went extinct during the Pliocene Epoch.
Published Extinct warbler's genome sequenced from museum specimens
(via sciencedaily.com) Original source The Bachman's warbler, a songbird that was last seen in North America nearly 40 years ago, was a distinct species and not a hybrid of its two living sister species, according a new study in which the full genomes of seven museum specimens of the bird were sequenced.
Published Einstein and Euler put to the test at the edge of the Universe
(via sciencedaily.com) Original source The cosmos is a unique laboratory for testing the laws of physics, in particular those of Euler and Einstein. Euler described the movements of celestial objects, while Einstein described the way in which celestial objects distort the Universe. Since the discovery of dark matter and the acceleration of the Universe's expansion, the validity of their equations has been put to the test: are they capable of explaining these mysterious phenomena? A team has developed the first method to find out. It considers a never-before-used measure: time distortion.
Published Never-before-seen way to annihilate a star
(via sciencedaily.com) Original source Astronomers studying a powerful gamma-ray burst, may have detected a never-before-seen way to destroy a star. Unlike most GRBs, which are caused by exploding massive stars or the chance mergers of neutron stars, astronomers have concluded that this GRB came instead from the collision of stars or stellar remnants in the jam-packed environment surrounding a supermassive black hole at the core of an ancient galaxy.
Published Astronomers discover new link between dark matter and clumpiness of the universe
(via sciencedaily.com) Original source Researchers reveal a theoretical breakthrough that may explain both the nature of invisible dark matter and the large-scale structure of the universe known as the cosmic web. The result establishes a new link between these two longstanding problems in astronomy, opening new possibilities for understanding the cosmos. The research suggests that the 'clumpiness problem,' which centres on the unexpectedly even distribution of matter on large scales throughout the cosmos, may be a sign that dark matter is composed of hypothetical, ultra-light particles called axions. The implications of proving the existence of hard-to-detect axions extend beyond understanding dark matter and could address fundamental questions about the nature of the universe itself.
Published DESI early data release holds nearly two million objects
(via sciencedaily.com) Original source The first batch of data from the Dark Energy Spectroscopic Instrument is now available for researchers to explore. Taken during the experiment's 'survey validation' phase, the data include distant galaxies and quasars as well as stars in our own Milky Way.
Published Astronomers discover supernova explosion through rare 'cosmic magnifying glasses'
(via sciencedaily.com) Original source An international team of scientists recently discovered an exceptionally rare gravitationally lensed supernova, which the team named 'SN Zwicky.' Located more than 4 billion light years away, the supernova was magnified nearly 25 times by a foreground galaxy acting as a lens. The discovery presents a unique opportunity for astronomers to learn more about the inner cores of galaxies, dark matter and the mechanics behind universe expansion.
Published Lost giants: New study reveals the abundance decline of African megafauna
(via sciencedaily.com) Original source A groundbreaking new paper focuses on the size and abundance of living and fossil African large mammals, shedding light on the ecological dynamics behind the decline of these iconic creatures. The findings challenge previous assumptions about the causes of megafaunal extinctions in Africa and provide new insights into the restructuring of ecosystems over millions of years.
Published New study identifies mechanism driving the sun's fast wind
(via sciencedaily.com) Original source Researchers used data from NASA's Parker Solar Probe to explain how the solar wind is capable of surpassing speeds of 1 million miles per hour. They discovered that the energy released from the magnetic field near the sun's surface is powerful enough to drive the fast solar wind, which is made up of ionized particles -- called plasma -- that flow outward from the sun.
Published Webb Space Telescope detects universe's most distant complex organic molecules
(via sciencedaily.com) Original source Researchers have detected complex organic molecules in a galaxy more than 12 billion light-years away from Earth -- the most distant galaxy in which these molecules are now known to exist. Thanks to the capabilities of the recently launched James Webb Space Telescope and careful analyses from the research team, a new study lends critical insight into the complex chemical interactions that occur in the first galaxies in the early universe.
Published Early universe crackled with bursts of star formation, Webb shows
(via sciencedaily.com) Original source Among the most fundamental questions in astronomy is: How did the first stars and galaxies form? NASA's James Webb Space Telescope is already providing new insights into this question. One of the largest programs in Webb's first year of science is the JWST Advanced Deep Extragalactic Survey, or JADES, which will devote about 32 days of telescope time to uncover and characterize faint, distant galaxies. While the data is still coming in, JADES already has discovered hundreds of galaxies that existed when the universe was less than 600 million years old. The team also has identified galaxies sparkling with a multitude of young, hot stars.
Published Weigh a quasar's galaxy with precision
(via sciencedaily.com) Original source Scientists have managed to weigh -- more precisely than any other technique -- a galaxy hosting a quasar, thanks to the fact that it acts as a gravitational lens. Detection of strong gravitational lensing quasars is expected to multiply with the launch of Euclid this summer.
Published Eventually everything will evaporate, not only black holes
(via sciencedaily.com) Original source New theoretical research has shown that Stephen Hawking was likely right about black holes, although not completely. Due to Hawking radiation, black holes will eventually evaporate, but the event horizon is not as crucial as had been believed. Gravity and the curvature of spacetime cause this radiation too. This means that all large objects in the universe, like the remnants of stars, will eventually evaporate.