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Categories: Geoscience: Geology, Space: Astrophysics
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 Past climate change to blame for Antarctica's giant underwater landslides



Scientists found weak, biologically-rich layers of sediments hundreds of meters beneath the seafloor which crumbled as oceans warmed and ice sheets declined. The landslides were discovered in the eastern Ross Sea in 2017, by an international team of scientists during the Italian ODYSSEA expedition, and scientists revisited the area in 2018 as part of the International Ocean Discovery Program (IODP) Expedition 374 where they collected sediment cores to understand what caused them.
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 Physicists take the temperature of fluid flows and discover new role for turbulence



A team of physicists has discovered a new role for a specific type of turbulence -- a finding that sheds light on fluid flows ranging from the Earth's liquid core to boiling water.
Published 'Warm Ice Age' changed climate cycles



Approximately 700,000 years ago, a 'warm ice age' permanently changed the climate cycles on Earth. During this exceptionally warm and moist period, the polar glaciers greatly expanded. A research team identified this seemingly paradoxical connection. The shift in the Earth's climate represents a critical step in our planet's later climate development.
Published Out of this world control on Ice Age cycles



A research team, composed of climatologists and an astronomer, have used an improved computer model to reproduce the cycle of ice ages (glacial periods) 1.6 to 1.2 million years ago. The results show that the glacial cycle was driven primarily by astronomical forces in quite a different way than it works in the modern age. These results will help us to better understand the past, present, and future of ice sheets and the Earth's climate.
Published Astronomers observe the first radiation belt seen outside of our solar system



Astronomers have described the first radiation belt observed outside our solar system, using a coordinated array of 39 radio dishes from Hawaii to Germany to obtain high-resolution images. The images of persistent, intense radio emissions from an ultracool dwarf reveal the presence of a cloud of high-energy electrons trapped in the object's powerful magnetic field, forming a double-lobed structure analogous to radio images of Jupiter's radiation belts.
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 Great Basin: History of water supply in one of the driest regions in the USA



An international team has reconstructed the evolution of groundwater in the Great Basin, USA -- one of the driest regions on Earth -- up to 350,000 years into the past with unprecedented accuracy. The results shed new light on the effects of climate change on water supply and provide important insights for the sustainable use of groundwater resources.
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 Hidden views of vast stellar nurseries



Astronomers have created a vast infrared atlas of five nearby stellar nurseries by piecing together more than one million images. These large mosaics reveal young stars in the making, embedded in thick clouds of dust. Thanks to these observations, astronomers have a unique tool with which to decipher the complex puzzle of stellar birth.
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 Astronomers find no young binary stars near Milky Way's black hole



Scientists analyzed over a decade's worth of data about 16 young supermassive stars orbiting the supermassive black hole at the center of the Milky Way galaxy. Supermassive stars typically are formed in pairs, but the new study found that all 16 of the stars were singletons. The findings support a scenario in which the supermassive black hole drives nearby stars to either merge or be disrupted, with one of the pair being ejected from the system.
Published How life and geology worked together to forge Earth's nutrient rich crust



Around 500 million years ago life in the oceans rapidly diversified. In the blink of an eye -- at least in geological terms -- life transformed from simple, soft-bodied creatures to complex multicellular organisms with shells and skeletons. Now, research has shown that the diversification of life at this time also led to a drastic change in the chemistry of Earth's crust -- the uppermost layer we walk on and, crucially, the layer which provides many of the nutrients essential to life.
Published Researchers measure the light emitted by a sub-Neptune planet's atmosphere



Researchers observed exoplanet GJ 1214b's atmosphere by measuring the heat it emits while orbiting its host star. Astronomers directly detected the light emitted by a sub-Neptune exoplanet -- a category of planets that are larger than Earth but smaller than Neptune.
Published Galactic bubbles are more complex than imagined



Astronomers have revealed new evidence about the properties of the giant bubbles of high-energy gas that extend far above and below the Milky Way galaxy's center.
Published New clues about the rise of Earth's continents



New research deepens the understanding of Earth's crust by testing and ultimately eliminating one popular hypothesis about why continental crust is lower in iron and more oxidized compared to oceanic crust. The iron-poor composition of continental crust is a major reason why vast portions of the Earth's surface stand above sea level as dry land, making terrestrial life possible today. The study uses laboratory experiments to show that the iron-depleted, oxidized chemistry typical of Earth's continental crust likely did not come from crystallization of the mineral garnet, as a popular explanation proposed in 2018.
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.