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Categories: Paleontology: Climate, Space: Exploration

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When a star like our Sun reaches the end of its life, it can ingest the surrounding planets and asteroids that were born with it. Now, researchers have found a unique signature of this process for the first time -- a scar imprinted on the surface of a white dwarf star.

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NASA's James Webb Space Telescope has found the best evidence yet for emission from a neutron star at the site of a recently observed supernova. The supernova, known as SN 1987A, was a core-collapse supernova, meaning the compacted remains at its core formed either a neutron star or a black hole. Evidence for such a compact object has long been sought, and while indirect evidence for the presence of a neutron star has previously been found, this is the first time that the effects of high-energy emission from the probable young neutron star have been detected.

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Astronomers have characterized a bright quasar, finding it to be not only the brightest of its kind, but also the most luminous object ever observed. Quasars are the bright cores of distant galaxies and they are powered by supermassive black holes. The black hole in this record-breaking quasar is growing in mass by the equivalent of one Sun per day, making it the fastest-growing black hole to date.

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Scientists suspect Mars once had long-lived rivers, lakes and streams. Today, water on Mars is found in ice at the poles and trapped below the Martian surface. Researchers now reveal that Mars also may have had hydrothermal systems based on the hydrated magnesium sulfate the rover identified in the volcanic rocks.

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A detailed survey of the volcanic underwater deposits around the Kikai caldera in Japan clarified the deposition mechanisms as well as the event's magnitude. As a result, the research team found that the event 7,300 years ago was the largest volcanic eruption in the Holocene by far.

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A new computer model mimics Moon dust so well that it could lead to smoother and safer Lunar robot teleoperations.

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It has been long assumed that Utah's Bonneville Salt Flats was formed as its ancient namesake lake dried up 13,000 years ago. But new research has gutted that narrative, determining these crusts did not form until several thousand years after Lake Bonneville disappeared, which could have important implications for managing this feature that has been shrinking for decades to the dismay of the racing community and others who revere the saline pan 100 miles west of Salt Lake City. Relying on radiocarbon analysis of pollen found in salt cores, the study concludes the salt began accumulating between 5,400 and 3,500 years ago, demonstrating how this geological feature is not a permanent fixture on the landscape.

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Mars was once a wet world. The geological record of the Red Planet shows evidence for water flowing on the surface -- from river deltas to valleys carved by massive flash floods. But a new study shows that no matter how much rainfall fell on the surface of ancient Mars, very little of it seeped into an aquifer in the planet's southern highlands.

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The supermassive black hole in the center of the Milky Way is spinning so quickly it is warping the spacetime surrounding it into a shape that can look like a football, according to a new study. That football shape suggests the black hole is spinning at a substantial speed, which researchers estimated to be about 60% of its potential limit.

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A few years ago, astronomers uncovered one of the Milky Way's greatest secrets: an enormous, wave-shaped chain of gaseous clouds in our sun's backyard, giving birth to clusters of stars along the spiral arm of the galaxy we call home. Naming this astonishing new structure the Radcliffe Wave, the team now reports that the Radcliffe Wave not only looks like a wave, but also moves like one -- oscillating through space-time much like 'the wave' moving through a stadium full of fans.

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A new paradigm is taking shape in the space industry as the countries and entities accessing space continue to grow and diversify. This dynamic landscape creates both competition and potential for scientific collaboration, as well as the challenges and opportunities of progress.

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A team found evidence for hydrothermal or metamorphic activity within the icy dwarf planets Eris and Makemake, located in the Kuiper Belt. Methane detected on their surfaces has the tell-tale signs of warm or even hot geochemistry in their rocky cores, which is markedly different than the signature of methane from a comet.

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A geologist has revealed intriguing insights into the volcanic activity on Mars. He proposes that Mars has significantly more diverse volcanism than previously realized, driven by an early form of crust recycling called vertical tectonics. The findings shed light on the ancient crust of Mars and its potential implications for understanding early crustal recycling on both Mars and Earth.

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If gravitational condensate stars (or gravastars) actually existed, they would look similar to black holes to a distant observer. Two theoretical physicists have now found a new solution to Albert Einstein's theory of general relativity, according to which gravitational stars could be structured like a Russian matryoshka doll, with one gravastar located inside another.

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This study reports widespread mineral carbonation of mantle rocks in an oceanic transform fueled by magmatic degassing of CO2. The findings describe a previously unknown part of the geological carbon cycle in transform faults that represent one of the three principal plate boundaries on Earth. The confluence of tectonically exhumed mantle rocks and CO2-rich alkaline basalt formed through limited extents of melting characteristic of the St. Paul's transform faults may be a pervasive feature at oceanic transform faults in general. Because transform faults have not been accounted for in previous estimates of global geological CO2 fluxes, the mass transfer of magmatic CO2 to the altered oceanic mantle and seawater may be larger than previously thought.

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Astronomers have uncovered evidence of how the enigmatic gap in the size distribution of exoplanets at around two Earth radii emerges. Their computer simulations demonstrate that the migration of icy, so-called sub-Neptunes into the inner regions of their planetary systems could account for this phenomenon. As they draw closer to the central star, evaporating water ice forms an atmosphere that makes the planets appear larger than in their frozen state. Simultaneously, smaller rocky planets gradually lose a portion of their original gaseous envelope, causing their measured radius to shrink over time.

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The Greenland ice sheet lies thousands of miles from North America yet holds clues to the distant continent's environmental history. Nearly two miles thick in places, the ice sheet grows as snow drifts from the sky and builds up over time. But snow isn't the only thing carried in by air currents that swirl around the atmosphere, with microscopic pollen grains and pieces of ash mixing with snowfall and preserving records of the past in the ice. A new study examined these pollen grains and identified how eastern Canada's forests grew, retreated, and changed through time.

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Researchers have uncovered the first direct evidence that the West Antarctic Ice Sheet shrunk suddenly and dramatically at the end of the Last Ice Age, around eight thousand years ago. The evidence, contained within an ice core, shows that in one location the ice sheet thinned by 450 meters -- that's more than the height of the Empire State Building -- in just under 200 years.

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Inspired during field work in South Australia's Flinders Ranges, geoscientists have proposed that all-time low volcanic carbon dioxide emissions triggered a 57-million-year-long global 'Sturtian' ice age.

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Saturn's moon Mimas harbors a global ocean beneath its icy shell, discovered through analysis of its orbit by Cassini spacecraft data. This ocean formed just 5-15 million years ago, making Mimas a prime candidate for studying early ocean formation and potential for life. This discovery suggests life-essential conditions might exist on seemingly inactive moons, expanding our search for life beyond Earth.