Showing 20 articles starting at article 501
< Previous 20 articles Next 20 articles >
Categories: Paleontology: Early Mammals and Birds, Space: Exploration
Published Evolutionary origins of the pygmy right whale
(via sciencedaily.com) Original source Researchers have finally settled a decades-long dispute about the evolutionary origins of the pygmy right whale.
Published Gauging the strength of ancient and active rivers beyond Earth
(via sciencedaily.com) Original source A new technique allows scientists to see how intensely rivers used to flow on Mars, and how they currently flow on Titan. The method uses satellite observations to estimate the rate at which rivers move fluid and sediment downstream.
Published Webb Telescope detects most distant active supermassive black hole
(via sciencedaily.com) Original source Researchers have discovered the most distant active supermassive black hole to date with the James Webb Space Telescope (JWST). The galaxy, CEERS 1019, existed about 570 million years after the big bang, and its black hole is less massive than any other yet identified in the early universe.
Published Fossils reveal how ancient birds molted their feathers -- which could help explain why ancestors of modern birds survived when all the other dinosaurs died
(via sciencedaily.com) Original source Birds are the only group of dinosaurs that survived the asteroid-induced mass extinction 66 million years ago. But not all the birds alive at the time made it. Why the ancestors of modern birds lived while so many of their relatives died has been a mystery that paleontologists have been trying to solve for decades. Two new studies point to one possible factor: the differences between how modern birds and their ancient cousins molt their feathers.
Published Webb locates dust reservoirs in two supernovae
(via sciencedaily.com) Original source Researchers have made major strides in confirming the source of dust in early galaxies. Observations of two Type II supernovae, Supernova 2004et (SN 2004et) and Supernova 2017eaw (SN 2017eaw), have revealed large amounts of dust within the ejecta of each of these objects. The mass found by researchers supports the theory that supernovae played a key role in supplying dust to the early universe.
Published Large sub-surface granite formation signals ancient volcanic activity on Moon's dark side
(via sciencedaily.com) Original source A large formation of granite discovered below the lunar surface likely was formed from the cooling of molten lava that fed a volcano or volcanoes that erupted early in the Moon's history -- as long as 3.5 billion years ago.
Published New image from James Webb Space Telescope reveals astonishing Saturn and its rings
(via sciencedaily.com) Original source Saturn's iconic rings seem to glow eerily in this incredible infrared picture, which also unveils unexpected features in Saturn's atmosphere. This image serves as context for an observing program that will test the telescope's capacity to detect faint moons around the planet and its bright rings. Any newly discovered moons could help scientists put together a more complete picture of the current system of Saturn, as well as its past.
Published Gullies on Mars could have been formed by recent periods of liquid meltwater, study suggests
(via sciencedaily.com) Original source A study offers new insights into how water from melting ice could have played a recent role in the formation of ravine-like channels that cut down the sides of impact craters on Mars.
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 Life after death: Astronomers find a planet that shouldn't exist
(via sciencedaily.com) Original source The star would have inflated up to 1.5 times the planet's orbital distance -- engulfing the planet in the process -- before shrinking to its current size at only one-tenth of that distance.
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 First detection of crucial carbon molecule
(via sciencedaily.com) Original source Scientists detect a new carbon compound in space for the first time. Known as methyl cation (pronounced cat-eye-on) (CH3+), the molecule is important because it aids the formation of more complex carbon-based molecules. Methyl cation was detected in a young star system, with a protoplanetary disk, known as d203-506, which is located about 1,350 light-years away in the Orion Nebula.
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 Groundwork for future ultra-precise timing links to geosynchronous satellites
(via sciencedaily.com) Original source Scientists have demonstrated a capability long sought by physicists: transmitting extremely precise time signals through the air between far-flung locations at powers that are compatible with future space-based missions. The results could enable time transfer from the ground to satellites in geosynchronous orbit with femtosecond precision -- 10,000 times better than the existing state-of-the-art satellite approaches. It also would allow for successful synchronization using the bare minimum timing signal strength, which would make the system highly robust in the face of atmospheric disturbances.
Published Detection of an echo emitted by our Galaxy's black hole 200 years ago
(via sciencedaily.com) Original source An international team of scientists has discovered that Sagittarius A* (Sgr A*), the supermassive black hole at the centre of the Milky Way, emerged from a long period of dormancy some 200 years ago. The team, led by Frédéric Marin, a CNRS researcher at the Astronomical Strasbourg Observatory (CNRS/University of Strasbourg), has revealed the past awakening of this gigantic object, which is four million times more massive than the Sun. Their work is published in Nature on 21 June.