Showing 20 articles starting at article 481
< Previous 20 articles Next 20 articles >
Categories: Paleontology: Dinosaurs, Space: Exploration
Published Gauging the strength of ancient and active rivers beyond Earth



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



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



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



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



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



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



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'



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



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



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 Newly discovered Jurassic fossils in Texas



Scientists have filled a major gap in the state's fossil record -- describing the first known Jurassic vertebrate fossils in Texas. The weathered bone fragments are from the limbs and backbone of a plesiosaur, an extinct marine reptile.
Published Humans' ancestors survived the asteroid impact that killed the dinosaurs



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



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 Einstein and Euler put to the test at the edge of the Universe



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



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



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



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.
Published Jupiter's moon Europa may have had a slow evolution



Europa may have a metamorphic origin for the ocean. While some scientists speculated this, a research team shows that if Europa indeed formed from hydrated rocks (i.e., rocks have hydrogen and oxygen), then enough of Europa's interior should get hot enough to release water directly from the hydrated rocks to form the ocean and ice shell.
Published New dinosaur discovered: Ankylosaurs may have been far more diverse than originally thought



First armoured dinosaur to be described from the Isle of Wight in 142 years, shows Ankylosaurs may have been far more diverse than originally thought
Published Researchers demystify the unusual origin of the Geminids meteor shower



Princeton researchers used observations from NASA's Parker Solar Probe mission to deduce that it was likely a violent, catastrophic event -- such as a high-speed collision with another body or a gaseous explosion -- that created the Geminids meteoroid stream. Mysteries surrounding the origin of the Geminids have long fascinated scientists because, while most meteor showers are created when a comet emits a tail of ice and dust, the Geminids stem from an asteroid -- a chunk of rock that normally does not produce a tail. Until now, this unusual meteoroid stream had only been studied from Earth.