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Categories: Geoscience: Oceanography, Space: General
Published Metal scar found on cannibal star



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.
Published Barriers against Antarctic ice melt disappearing at the double



Undersea anchors of ice that help prevent Antarctica's land ice from slipping into the ocean are shrinking at more than twice the rate compared with 50 years ago, research shows. More than a third of these frozen moorings, known as pinning points, have decreased in size since the turn of the century, experts say. Further deterioration of pinning points, which hold in place the floating ice sheets that fortify Antarctica's land ice, would accelerate the continent's contribution to rising sea levels, scientists warn.
Published Webb finds evidence for neutron star at heart of young supernova remnant



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.
Published A new beginning: The search for more temperate Tatooines



Luke Skywalker's childhood might have been slightly less harsh if he'd grown up on a more temperate Tatooine -- like the ones identified in a new study. According to the study's authors, there are more climate-friendly planets in binary star systems -- in other words, those with two suns -- than previously known. And, they say, it may be a sign that, at least in some ways, the universe leans in the direction of orderly alignment rather than chaotic misalignment.
Published Stronger storms free more nutrients from mud flats



If storms become stronger in the future due to climate change, more nitrogen may be released from the bottom of coastal seas.
Published Brightest and fastest-growing: Astronomers identify record-breaking quasar



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.
Published Three years later, search for life on Mars continues



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.
Published Biggest Holocene volcano eruption found by seabed survey



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.
Published New realistic computer model will help robots collect Moon dust



A new computer model mimics Moon dust so well that it could lead to smoother and safer Lunar robot teleoperations.
Published Little groundwater recharge in ancient Mars aquifer, according to new models



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.
Published Mercury levels in tuna remain nearly unchanged since 1971



Tuna is one of the most popular seafoods worldwide. But this protein-rich fish can build up high levels of methylmercury from feeding on contaminated prey, like smaller fish or crustaceans. Despite efforts to reduce mercury emissions into the environment, researchers report that levels in tuna appear to be unchanged since 1971. They warn that more aggressive emission reduction targets are needed to start nudging down tuna mercury levels.
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 Gulf corals still suffering more than a decade after Deepwater Horizon oil spill, scientists report



Deep-water corals in the Gulf of Mexico are still struggling to recover from the devastating Deepwater Horizon oil spill in 2010, scientists report at the Ocean Science Meeting in New Orleans. Comparing images of more than 300 corals over 13 years -- the longest time series of deep-sea corals to date -- reveals that in some areas, coral health continues to decline to this day.
Published Spy-satellite images offer insights into historical ecosystem changes



New study advocates the use of more than one million declassified images for ecology and conservation. The images can offer better insights into the historical changes of ecosystems, species populations or changes in human influences on the environment dating back to the 1960s. Collaboration between ecologists, conservationists, and remote sensing experts is necessary to explore the full potential of the data.
Published Decline in microbial genetic richness in the western Arctic Ocean



Researchers analyzed archival samples of bacteria and archaea populations taken from the Beaufort Sea, bordering northwest Canada and Alaska. The samples were collected between 2004 and 2012, a period that included two years -- 2007 and 2012 -- in which the sea ice coverage was historically low. The researchers looked at samples taken from three levels of water: the summer mixed layer, the upper Arctic water below it and the Pacific-origin water at the deepest level. The study examined the microbes' genetic composition using bioinformatics and statistical analysis across the nine-year time span. Using this data, the researchers were able to see how changing environmental conditions were influencing the organisms' structure and function.
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 Viruses that can help 'dial up' carbon capture in the sea



Armed with a catalog of hundreds of thousands of DNA and RNA virus species in the world's oceans, scientists are now zeroing in on the viruses most likely to combat climate change by helping trap carbon dioxide in seawater or, using similar techniques, different viruses that may prevent methane's escape from thawing Arctic soil.
Published Giant Antarctic sea spiders reproductive mystery solved



Instead of carrying the babies until they hatched, as in most species of sea spiders, one parent (likely the father) spent two days attaching the eggs to the rocky bottom where they developed for several months before hatching as tiny larvae.
Published Anoxic marine basins are among the best candidates for deep-sea carbon sequestration



Anoxic marine basins may be among the most viable places to conduct large-scale carbon sequestration in the deep ocean, while minimizing negative impacts to marine life. As we explore ways to actively draw down the levels of carbon in the atmosphere, sending plant biomass to these barren, oxygen-free zones on the seafloor becomes an option worth considering.
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.