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Categories: Paleontology: Dinosaurs, Space: Cosmology
Published Multiple species of semi-aquatic dinosaur may have roamed pre-historic Britain



Palaeontologists studying a British dinosaur tooth have concluded that several distinct groups of spinosaurs -- dinosaurs with fearsome crocodile-like skulls -- inhabited southern England over 100 million years ago.
Published Astrophysicists confirm the faintest galaxy ever seen in the early universe



After the Big Bang, the universe expanded and cooled sufficiently for hydrogen atoms to form. In the absence of light from the first stars and galaxies, the universe entered a period known as the cosmic dark ages. The first stars and galaxies appeared several hundred million years later and began burning away the hydrogen fog left over from the Big Bang, rendering the universe transparent, like it is today. Researchers have now confirmed the existence of a distant, faint galaxy typical of those whose light burned through the hydrogen atoms; the finding should help them understand how the cosmic dark ages ended.
Published 107-million-year-old pterosaur bones: Oldest in Australia



A team of researchers have confirmed that 107-million-year-old pterosaur bones discovered more than 30 years ago are the oldest of their kind ever found in Australia, providing a rare glimpse into the life of these powerful, flying reptiles that lived among the dinosaurs.
Published X-ray emissions from black hole jets vary unexpectedly, challenging leading model of particle acceleration



Black hole jets are known to emit x-rays, but how they accelerate particles to this high-energy state is still a mystery. Surprising new findings appear to rule out a leading theory, opening the door to reimagining how particle acceleration works. One model of how jets generate x-rays expects the jets' x-ray emissions to remain stable over long time scales. However, the new paper found that the x-ray emissions of a statistically significant number of jets varied over just a few years.
Published Helium nuclei research advances our understanding of cosmic ray origin and propagation



The latest observations from Low Earth Orbit with the International Space Station provide further evidence of spectral hardening and softening of cosmic ray particles.
Published Dinosaurs were the first to take the perspectives of others



Understanding that others hold different viewpoints from your own is essential for human sociality. Adopting another person's visual perspective is a complex skill that emerges around the age of two. A new study suggests that this ability first arose in dinosaurs, at least 60 million years before it appeared in mammals. These findings challenge the idea that mammals were the originators of novel and superior forms of intelligence in the wake of the dinosaur extinction.
Published An X-ray look at the heart of powerful quasars



Researchers have observed the X-ray emission of the most luminous quasar seen in the last 9 billion years of cosmic history, known as SMSS J114447.77-430859.3, or J1144 for short. The new perspective sheds light on the inner workings of quasars and how they interact with their environment.
Published Fossil of mosasaur with bizarre 'screwdriver teeth' found in Morocco



Scientists have discovered a new species of mosasaur, a sea-dwelling lizard from the age of the dinosaurs, with strange, ridged teeth unlike those of any known reptile. Along with other recent finds from Africa, it suggests that mosasaurs and other marine reptiles were evolving rapidly up until 66 million years ago, when they were wiped out by an asteroid along with the dinosaurs and around 90% of all species on Earth.
Published Radio signal reveals supernova origin



Astronomers reveal the origin of a thermonuclear supernova explosion. Strong emission lines of helium and the first detection of such a supernova in radio waves show that the exploding white dwarf star had a helium-rich companion.
Published Astronomers reveal the largest cosmic explosion ever seen



Astronomers have uncovered the largest cosmic explosion ever witnessed. The explosion is more than ten times brighter than any known supernova and three times brighter than the brightest tidal disruption event, where a star falls into a supermassive black hole.
Published Researchers find new approach to explore earliest universe dynamics with gravitational waves



Researchers have discovered a new generic production mechanism of gravitational waves generated by a phenomenon known as oscillons.
Published Hidden supermassive black holes brought to life by galaxies on collision course



Astronomers have found that supermassive black holes obscured by dust are more likely to grow and release tremendous amounts of energy when they are inside galaxies that are expected to collide with a neighbouring galaxy.
Published Celestial monsters at the origin of globular clusters



Globular clusters are the most massive and oldest star clusters in the Universe. They can contain up to 1 million of them. The chemical composition of these stars, born at the same time, shows anomalies that are not found in any other population of stars. Explaining this specificity is one of the great challenges of astronomy. After having imagined that supermassive stars could be at the origin, a team believes it has discovered the first chemical trace attesting to their presence in globular proto-clusters, born about 440 million years after the Big Bang.
Published Measurement of the Universe's expansion rate weighs in on a longstanding debate in physics and astronomy



A team used a first-of-its-kind technique to measure the expansion rate of the Universe, providing insight that could help more accurately determine the Universe's age and help physicists and astronomers better understand the cosmos.
Published Giants of the Jurassic seas were twice the size of a killer whale



There have been heated debates over the size of Jurassic animals. The speculation was set to continue, but now a chance discovery in an Oxfordshire museum has led to palaeontologists publishing a paper on a Jurassic species potentially reaching a whopping 14.4 meters -- twice the size of a killer whale.
Published Neutron star's X-rays reveal 'photon metamorphosis'



A 'beautiful effect' predicted by quantum electrodynamics (QED) can explain the puzzling first observations of polarized X-rays emitted by a magnetar -- a neutron star featuring a powerful magnetic field, according to an astrophysicist.
Published Astronomers find distant gas clouds with leftovers of the first stars



Using ESO's Very Large Telescope (VLT), researchers have found for the first time the fingerprints left by the explosion of the first stars in the Universe. They detected three distant gas clouds whose chemical composition matches what we expect from the first stellar explosions. These findings bring us one step closer to understanding the nature of the first stars that formed after the Big Bang.
Published Most massive touching stars ever found will eventually collide as black holes



A new study looked at a known binary star (two stars orbiting around a mutual center of gravity), analyzing starlight obtained from a range of ground- and space-based telescopes. The researchers found that the stars, located in a neighboring dwarf galaxy called the Small Magellanic Cloud, are in partial contact and swapping material with each other, with one star currently 'feeding' off the other. They orbit each other every three days and are the most massive touching stars (known as contact binaries) yet observed.
Published Astronomers solve the 60-year mystery of quasars -- the most powerful objects in the Universe



Scientists have unlocked one of the biggest mysteries of quasars -- the brightest, most powerful objects in the Universe -- by discovering that they are ignited by galaxies colliding.
Published Webb reveals early-universe prequel to huge galaxy cluster



Every giant was once a baby, though you may never have seen them at that stage of their development. NASA's James Webb Space Telescope has begun to shed light on formative years in the history of the universe that have thus far been beyond reach: the formation and assembly of galaxies. For the first time, a protocluster of seven galaxies has been confirmed at a distance that astronomers refer to as redshift 7.9, or a mere 650 million years after the big bang. Based on the data collected, astronomers calculated the nascent cluster's future development, finding that it will likely grow in size and mass to resemble the Coma Cluster, a monster of the modern universe.