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Categories: Geoscience: Geology, Offbeat: Space

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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 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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Our planet's lithosphere is broken into several tectonic plates. Their configuration is ever-shifting, as supercontinents are assembled and broken up, and oceans form, grow, and then start to close in what is known as the Wilson cycle.

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A new study offers a glimpse into the possible impact of climate change on coastal wetlands 50 years or longer into the future. Scientists are usually forced to rely on computer models to project the long-term effects of rising seas, but an unexpected set of circumstances enabled a real-world experiment along the Gulf Coast.

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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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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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Rocks once buried deep in ancient subduction zones -- where tectonic plates collide -- could help scientists make better predictions of how these zones behave during the years between major earthquakes, according to a research team.

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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.

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Two astrophysicists have finally solved a 20-year-old astrophysical puzzle concerning the lower-than-expected amounts of the element sulphur found in Planetary Nebulae (PNe) in comparison to expectations and measurements of other elements and other types of astrophysical objects. The expected levels of sulphur have long appeared to be 'missing in action'. However, they have now finally reported for duty after hiding in plain sight, as a result of leveraging highly accurate and reliable data.

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The Seattle fault zone is a network of shallow faults slicing through the lowlands of Puget Sound, threatening to create damaging earthquakes for the more than four million people who live there. A new origin story, proposed in a new study, could explain the fault system's earliest history and help scientists improve hazard modeling for the densely populated region.

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Black holes not only existed at the dawn of time, they birthed new stars and supercharged galaxy formation, a new analysis of James Webb Space Telescope data suggests.

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The Circumpolar Current works as a regulator of the planet's climate. Its origins were thought to have caused the formation of the permanent ice in Antarctica about 34 million years ago. Now, a study has cast doubt on this theory, and has changed the understanding of how the ice sheet in Antarctic developed in the past, and what this could mean in the future as the planet's climate changes.

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The earliest galaxies are thought to have formed as the gravitational pull of dark matter, which has been impossible to study directly, slowly drew in enough hydrogen and helium to ignite stars. But astrophysicists now show that after the Big Bang, hydrogen and helium gas bounced at supersonic speeds off dense, slowly moving clumps of cold dark matter. When the gas fell back in millennia later, stars formed all at once, creating small, exceptionally bright galaxies. If models of cold dark matter are correct, the James Webb Space Telescope should be able to find patches of bright galaxies in the early universe, potentially offering the first effective test for theories about dark matter. If it doesn't, scientists have to go back to the drawing board with dark matter.

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Geoscientists have uncovered a missing link in the enigmatic story of how the continents developed- - a revised origin story that doesn't require the start of plate tectonics or any external factor to explain their formation. Instead, the findings rely solely on internal geological forces that occurred within oceanic plateaus that formed during the first few hundred million years of Earth's history.