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Categories: Geoscience: Oceanography, Offbeat: Space
Published What turned Earth into a giant snowball 700 million years ago? Scientists now have an answer
(via sciencedaily.com) Original source 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
(via sciencedaily.com) Original source 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 Astrophysicists crack the case of 'disappearing' Sulphur in planetary nebulae
(via sciencedaily.com) Original source 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.
Published How kelp forests persisted through the large 2014-2016 Pacific marine heatwave
(via sciencedaily.com) Original source New research reveals that denser, and more sheltered, kelp forests can withstand serious stressors amid warming ocean temperatures.
Published Which came first: Black holes or galaxies?
(via sciencedaily.com) Original source 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 Small but mighty -- study highlights the abundance and importance of the ocean's tiniest inhabitants
(via sciencedaily.com) Original source New research sheds light on tiny plankton, which measure less than 0.02mm in diameter but can make up more than 70% of the plankton biomass found in the ocean.
Published Study challenges the classical view of the origin of the Antarctic Circumpolar Current and warns of its vulnerability
(via sciencedaily.com) Original source 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.
Published Vitamin B12 adaptability in Antarctic algae has implications for climate change, life in the Southern Ocean
(via sciencedaily.com) Original source The algae P. antarctica has two forms of the enzyme that makes the amino acid methionine, one needing B12, and one that is slower, but doesn't need it. This means it has the ability to adapt and survive with low B12 availability. The presence of the MetE gene in P. antarctica gives the algae the ability to adapt to lower vitamin B12 availability, giving it a potential advantage to bloom in the early austral spring when bacterial production is low. P. antarctica takes in the CO2 and releases oxygen through photosynthesis. Understanding its ability to grow in environments with low vitamin B12 availability can help climate modelers make more accurate predictions.
Published Tidal landscapes a greater carbon sink than previously thought
(via sciencedaily.com) Original source Mangroves and saltmarshes sequester large amounts of carbon, mitigating the greenhouse effect. New research shows that these environments are perhaps twice as effective as previously thought.
Published Engineers unmask nanoplastics in oceans for the first time, revealing their true shapes and chemistry
(via sciencedaily.com) Original source Millions of tons of plastic waste enter the oceans each year. The sun's ultraviolet light and ocean turbulence break down these plastics into invisible nanoparticles that threaten marine ecosystems. In a new study, engineers have presented clear images of nanoplastics in ocean water off the coasts of China, South Korea and the United States, and in the Gulf of Mexico. These tiny plastic particles, which originated from such consumer products as water bottles, food packaging and clothing, were found to have surprising diversity in shape and chemical composition.
Published Bright galaxies put dark matter to the test
(via sciencedaily.com) Original source 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 Unprecedented ocean heating shows risks of a world 3°C warmer
(via sciencedaily.com) Original source New research examines the causes of the record-breaking ocean temperatures witnessed in 2023.
Published As sea otters recolonize California estuary, they restore its degraded geology
(via sciencedaily.com) Original source As sea otters recolonize a California estuary, they are restoring its degraded geology by keeping populations of overgrazing marsh crabs in check, a new study shows. The crabs' appetite for plant roots, and their tunneling behavior had caused many of the estuary's marshes and creekbanks to erode and collapse in the otters' absence. Today, erosion has slowed by up to 90% in areas with large otter populations and marshes and streambeds are restabilizing.
Published Geoengineering may slow Greenland ice sheet loss
(via sciencedaily.com) Original source Modeling shows that stratospheric aerosol injection has the potential to reduce ice sheet loss due to climate change.
Published New research shows how pollutants from aerosols and river run-off are changing the marine phosphorus cycle in coastal seas
(via sciencedaily.com) Original source New research sheds light on how pollutants from aerosols and river run-off are impacting coastal seas. The research identified an 'Anthropogenic Nitrogen Pump' which changes the phosphorus cycle and therefore likely coastal biodiversity and associated ecosystem services.
Published Some plastic straws degrade quicker than others
(via sciencedaily.com) Original source Not all plastics are created the same, and some last longer in the ocean than others. Scientists have been working for years to quantify the environmental lifetimes of a wide range of plastic goods to see which have the shortest and longest lifespans in the ocean. To determine what plastics persist in the ocean, the team tests different products in large tanks that recreate the natural ocean environment.
Published Staggering structure in 19 nearby spiral galaxies
(via sciencedaily.com) Original source The James Webb Space Telescope observed 19 nearby face-on spiral galaxies in near- and mid-infrared light as part of its contributions to the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) program.
Published Researchers spying for signs of life among exoplanet atmospheres
(via sciencedaily.com) Original source The next generation of advanced telescopes could sharpen the hunt for potential extraterrestrial life by closely scrutinizing the atmospheres of nearby exoplanets, new research suggests.
Published Astronomers spot 18 black holes gobbling up nearby stars
(via sciencedaily.com) Original source Scientists have identified 18 new tidal disruption events (TDEs) -- extreme instances when a nearby star is tidally drawn into a black hole and ripped to shreds. The detections more than double the number of known TDEs in the nearby universe.
Published Confirmation of ancient lake on Mars builds excitement for Perseverance rover's samples
(via sciencedaily.com) Original source Ground-penetrating radar on board NASA's Mars Perseverance rover has confirmed that the Jezero Crater, formed by an ancient meteor impact just north of the Martian equator, once harbored a vast lake and river delta. Over eons, sediment deposition and erosion within the crater shaped the geologic formations visible on the surface today. The discovery of lake sediments reinforces the hope that traces of life might be found in soil and rock samples collected by Perseverance.