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Categories: Paleontology: Climate, Space: Exploration

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At the center of every galaxy is a supermassive black hole. Beyond a certain size, these become active, emitting huge amounts of radiation, and are then called quasars. It is thought these are activated by the presence of massive dark matter halos (DMH) surrounding the galaxy, directing matter towards the center, feeding the black hole. A team has now surveyed hundreds of ancient quasars and found this behavior is very consistent throughout history. This is surprising, as many large-scale processes show variation throughout the life of the universe, so the mechanism of quasar activation could have implications for the evolution of the entire universe.

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As the universe evolves, scientists expect large cosmic structures to grow at a certain rate: dense regions such as galaxy clusters would grow denser, while the void of space would grow emptier.

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A new investigation with NASA's James Webb Space Telescope into K2-18 b, an exoplanet 8.6 times as massive as Earth, has revealed the presence of carbon-bearing molecules including methane and carbon dioxide. Webb's discovery adds to recent studies suggesting that K2-18 b could be a Hycean exoplanet, one which has the potential to possess a hydrogen-rich atmosphere and a water ocean-covered surface.

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A new article hints at the existence of several black holes in the Hyades cluster -- the closest open cluster to our solar system -- which would make them the closest black holes to Earth ever detected.

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In experiments aboard the International Space Station, a surface treatment developed engineers prevented the growth of microbial biofims. These films can damage equipment and potentially cause illness.

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Massive burst of X-rays detected by astronomers indicates material three times the mass of Earth burning up in a black hole. They observed a star like our own Sun being eaten away every time it orbits close. First time a Sun-like star being repeatedly disrupted by a low mass black hole has been seen, opening the possibility of a range of star and black hole combinations to be discovered.

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New research has uncovered a possible clue as to why glaciers that terminate at the sea are retreating at unprecedented rates: the bursting of tiny, pressurized bubbles in underwater ice.

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Antarctica's vast ice masses seem far away, yet they store enough water to raise global sea levels by several meters. A team of experts has now provided the first systematic stability inspection of the ice sheet's current state. Their diagnosis: While they found no indication of irreversible, self-reinforcing retreat of the ice sheet in West Antarctica yet, global warming to date could already be enough to trigger the slow but certain loss of ice over the next hundreds to thousands of years.

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Astronomers have detected the magnetic field of a galaxy so far away that its light has taken more than 11 billion years to reach us: we see it as it was when the Universe was just 2.5 billion years old. The result provides astronomers with vital clues about how the magnetic fields of galaxies like our own Milky Way came to be.

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The planet HAT-P-32b is losing so much of its atmospheric helium that the trailing gas tails are among the largest structures yet known any planet outside our solar system. Three-dimensional (3D) simulations helped model the flow of the planet's atmosphere. The scientists hope to widen their planet-observing net and survey 20 additional star systems to find more planets losing their atmosphere and learn about their evolution.

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NASA's James Webb Space Telescope has begun the study of one of the most renowned supernovae, SN 1987A (Supernova 1987A). Located 168,000 light-years away in the Large Magellanic Cloud, SN 1987A has been a target of intense observations at wavelengths ranging from gamma rays to radio for nearly 40 years, since its discovery in February of 1987. New observations by Webb's NIRCam (Near-Infrared Camera) provide a crucial clue to our understanding of how a supernova develops over time to shape its remnant.

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With a remarkable observational campaign that involved 12 telescopes both on the ground and in space, including three European Southern Observatory (ESO) facilities, astronomers have uncovered the strange behavior of a pulsar, a super-fast-spinning dead star. This mysterious object is known to switch between two brightness modes almost constantly, something that until now has been an enigma. But astronomers have now found that sudden ejections of matter from the pulsar over very short periods are responsible for the peculiar switches.

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Astronomers have uncovered a link between Neptune's shifting cloud abundance and the 11-year solar cycle, in which the waxing and waning of the Sun's entangled magnetic fields drives solar activity.

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A new study has examined how T cells of the immune system are affected by weightlessness. The results could explain why astronauts' T cells become less active and less effective at fighting infection.

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Using ESO's Very Large Telescope (VLT), astronomers have observed a large dark spot in Neptune's atmosphere, with an unexpected smaller bright spot adjacent to it. This is the first time a dark spot on the planet has ever been observed with a telescope on Earth. These occasional features in the blue background of Neptune's atmosphere are a mystery to astronomers, and the new results provide further clues as to their nature and origin.

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New research has improved the accuracy of the parameters governing the expansion of the Universe. More accurate parameters will help astronomers determine how the Universe grew to its current state, and how it will evolve in the future.

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Radiocarbon dating on bones in the La Brea Tar Pits lead archaeologists to warn that history may be repeating itself.

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Magnetars are the strongest magnets in the Universe. These super-dense dead stars with ultra-strong magnetic fields can be found all over our galaxy but astronomers don't know exactly how they form. Now, using multiple telescopes around the world, researchers have uncovered a living star that is likely to become a magnetar. This finding marks the discovery of a new type of astronomical object -- massive magnetic helium stars -- and sheds light on the origin of magnetars.

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Recent paleogenomic research revealed that interbreeding was common among early human species. However, little was known about when, where, and how often this hominin interbreeding took place. Using paleoanthropological evidence, genetic data, and supercomputer simulations of past climate, a team of international researchers has found that interglacial climates and corresponding shifts in vegetation created common habitats for Neanderthals and Denisovans, increasing their chances for interbreeding and gene flow in parts of Europe and central Asia.

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A new study shows that the cheek teeth of proboscideans (elephants and their ancient relatives) evolved in response to dietary changes due to vegetation changes and climate change in East Africa during the last 26 million years.