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Categories: Paleontology: Climate, Space: Astronomy
Published Black hole at center of the Milky Way resembles a football



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.
Published Astronomers report oscillation of our giant, gaseous neighbor



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.
Published Under pressure -- space exploration in our time



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.
Published Evidence of geothermal activity within icy dwarf planets



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.
Published Diverse ancient volcanoes on Mars discovered by planetary scientist may hold clues to pre-plate tectonic activity on Earth



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.
Published A star like a Matryoshka doll: New theory for gravastars



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.
Published Researchers studying ocean transform faults, describe a previously unknown part of the geological carbon cycle



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.
Published Mysterious gap in size distribution of super-earths explained



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.
Published Ancient pollen trapped in Greenland ice uncovers changes in Canadian forests over 800 years



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.
Published Ice cores provide first documentation of rapid Antarctic ice loss in the past



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.
Published What turned Earth into a giant snowball 700 million years ago? Scientists now have an answer



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.
Published Mimas' surprise: Tiny moon of Saturn holds young ocean beneath icy shell



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.
Published A long, long time ago in a galaxy not so far away



Employing massive data sets collected through NASA's James Webb Space Telescope, astronomers are unearthing clues to conditions existing in the early universe. The team has catalogued the ages of stars in the Wolf--Lundmark--Melotte (WLM) galaxy, constructing the most detailed picture of it yet, according to the researchers. WLM, a neighbor of the Milky Way, is an active center of star formation that includes ancient stars formed 13 billion years ago.
Published Newly discovered carbon monoxide-runaway gap can help identify habitable exoplanets



A carbon monoxide (CO)-runaway gap identified in the atmospheres of Earth-like planets can help expand the search for habitable planets. This gap, identified through atmospheric modeling, is an indicator of a CO-rich atmosphere on Earth-like planets orbiting Sun-like stars. CO is an important compound for the formation of prebiotic organic compounds, which are building blocks for more complex molecules for the formation of life.
Published Which came first: Black holes or galaxies?



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.
Published Neptune-like exoplanets can be cloudy or clear



Astronomers have shown new atmospheric detail in a set of 15 exoplanets similar to Neptune. While none could support humanity, a better understanding of their behavior might help us to understand why we don't have a small Neptune, while most solar systems seem to feature a planet of this class.
Published Permafrost alone holds back Arctic rivers -- and a lot of carbon



A new study provides the first evidence that the Arctic's frozen soil is the dominant force shaping Earth's northernmost rivers, confining them to smaller areas and shallower valleys than rivers to the south. But as climate change weakens Arctic permafrost, the researchers calculate that every 1 degree Celsius of global warming could release as much carbon as 35 million cars emit in a year as polar waterways expand and churn up the thawing soil.
Published Gas on the run -- ALMA spots the shadow of a molecular outflow from a quasar when the Universe was less than one billion years old



Theoretical predictions have been confirmed with the discovery of an outflow of molecular gas from a quasar when the Universe was less than a billion years old.
Published Bright galaxies put dark matter to the test



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.
Published The hottest catalog of the year: Comprehensive list of slow-building solar flares



Although solar flares have been classified based on the amount of energy they emit at their peak, there has not been significant study into differentiating flares since slow-building flares were first discovered in the 1980s. Scientists have now shown that there is a significant amount of slower-type flares worthy of further investigation.