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Categories: Ecology: Extinction, Space: General
Published New class of Mars quakes reveals daily meteorite strikes
(via sciencedaily.com) Original source An international team of researchers combine orbital imagery with seismological data from NASA's Mars InSight lander to derive a new impact rate for meteorite strikes on Mars. Seismology also offers a new tool for determining the density of Mars' craters and the age of different regions of a planet.
Published Projected loss of brown macroalgae and seagrasses with global environmental change
(via sciencedaily.com) Original source Researchers predict that climate change will drive a substantial redistribution of brown seaweeds and seagrasses at the global scale. The projected changes are alarming due to the fundamental role seaweeds and seagrasses in coastal ecosystems and provide evidence of the pervasive impacts of climate change on marine life.
Published The density difference of sub-Neptunes finally deciphered
(via sciencedaily.com) Original source The majority of stars in our galaxy are home to planets. The most abundant are the sub-Neptunes, planets between the size of Earth and Neptune. Calculating their density poses a problem for scientists: depending on the method used to measure their mass, two populations are highlighted, the dense and the less dense. Is this due to an observational bias or the physical existence of two distinct populations of sub-Neptunes? Recent work argues for the latter.
Published Ammonites' fate sealed by meteor strike that wiped out dinosaurs
(via sciencedaily.com) Original source Ammonites were not in decline before their extinction, scientists have found.
Published Last surviving woolly mammoths were inbred but not doomed to extinction
(via sciencedaily.com) Original source The last population of woolly mammoths was isolated on Wrangel Island off the coast of Siberia 10,000 years ago, when sea levels rose and cut the mountainous island off from the mainland. A new genomic analysis reveals that the isolated mammoths, who lived on the island for the subsequent 6,000 years, originated from at most 8 individuals but grew to 200--300 individuals within 20 generations. The researchers report that the Wrangel Island mammoths' genomes showed signs of inbreeding and low genetic diversity but not to the extent that it can explain their ultimate (and mysterious) extinction.
Published To protect corals from summer heatwaves, we should help their microbial symbionts evolve heat tolerance in the lab
(via sciencedaily.com) Original source Most coral reef restoration efforts involve restocking reefs with nursery-grown corals. However, if these corals are of the same stock as their wild counterparts, they will be equally vulnerable to the heat stress that caused the bleaching event in the first place. Researchers discuss the potential of improving corals' chances by inducing the evolution of heat tolerance in their symbionts -- the mutualistic microbes that provide corals with nutrients in exchange for shelter and that are expelled during coral bleaching.
Published Precision instrument bolsters efforts to find elusive dark energy
(via sciencedaily.com) Original source Dark energy -- a mysterious force pushing the universe apart at an ever-increasing rate -- was discovered 26 years ago, and ever since, scientists have been searching for a new and exotic particle causing the expansion. Physicists combined an optical lattice with an atom interferometer to hold atoms in place for up to 70 seconds -- a record for an atom interferometer -- allowing them to more precisely test for deviations from the accepted theory of gravity that could be caused by dark energy particles such as chameleons or symmetrons. Though they detected no anomalies, they're improving the experiment to perform more sensitive tests of gravity, including whether gravity is quantized.
Published Future risk of coral bleaching set to intensify globally
(via sciencedaily.com) Original source Researchers have projected future marine heatwaves will cause coral reefs to be at severe risk of bleaching for longer periods than previously seen.
Published Ocean's loss of oxygen caused massive Jurassic extinction: Could it happen again?
(via sciencedaily.com) Original source Researchers have found a chemical clue in Italian limestone that explains a mass extinction of marine life in the Early Jurassic period, 183 million years ago. Volcanic activity pumped out CO2, warming oceans and lowering their oxygen levels. The findings may foretell the impact climate change and oxygen depletion might have on today's oceans.
Published Shocked quartz reveals evidence of historical cosmic airburst
(via sciencedaily.com) Original source Researchers continue to expand the case for the Younger Dryas Impact hypothesis. The idea proposes that a fragmented comet smashed into the Earth's atmosphere 12,800 years ago, causing a widespread climatic shift that, among other things, led to the abrupt reversal of the Earth's warming trend and into an anomalous near-glacial period called the Younger Dryas.
Published Pillars of creation star in new visualization from NASA's Hubble and Webb telescopes
(via sciencedaily.com) Original source Made famous in 1995 by NASA's Hubble Space Telescope, the Pillars of Creation in the heart of the Eagle Nebula have captured imaginations worldwide with their arresting, ethereal beauty. Now, NASA has released a new 3D visualization of these towering celestial structures using data from NASA's Hubble and James Webb space telescopes. This is the most comprehensive and detailed multiwavelength movie yet of these star-birthing clouds.
Published Predicting changes inside astronauts' bodies during space travel through blood sample analysis
(via sciencedaily.com) Original source The human body undergoes various transformations in space. However, a direct examination of organs and tissues is challenging. This study successfully identified these changes inside the body by analyzing tiny quantities of DNA and RNA molecules released from various tissues into the bloodstream while the astronauts were on the International Space Station (ISS).
Published Surprising phosphate finding in NASA's OSIRIS-REx asteroid sample
(via sciencedaily.com) Original source Early analysis of the asteroid Bennu sample returned by NASA's OSIRIS-REx mission has revealed dust rich in carbon, nitrogen, and organic compounds, all of which are essential components for life as we know it. Dominated by clay minerals, particularly serpentine, the sample mirrors the type of rock found at mid-ocean ridges on Earth. The magnesium-sodium phosphate found in the sample hints that the asteroid could have splintered off from an ancient, small, primitive ocean world.
Published Frog 'saunas' a lifeline for endangered frog populations
(via sciencedaily.com) Original source New biologist-designed shelters will help endangered frogs survive the devastating impacts of a deadly fungal disease by regulating their body temperature to fight off infections.
Published New evidence for how heat is transported below the sun's surface
(via sciencedaily.com) Original source Solar physicists have revealed the interior structure of the sun's supergranules, a flow structure that transports heat from the sun's hidden interior to its surface. The researchers' analysis of the supergranules presents a challenge to the current understanding of solar convection.
Published Telltale greenhouse gases could signal alien activity
(via sciencedaily.com) Original source If aliens modified a planet in their solar system to make it warmer, we'd be able to tell. A new study identifies the artificial greenhouse gases that would be giveaways of a terraformed planet.
Published Marsquakes may help reveal whether liquid water exists underground on red planet
(via sciencedaily.com) Original source If liquid water exists today on Mars, it may be too deep underground to detect with traditional methods used on Earth. But listening to earthquakes that occur on Mars -- or marsquakes -- could offer a new tool in the search.
Published First of its kind detection made in striking new Webb image
(via sciencedaily.com) Original source For the first time, a phenomenon astronomers have long hoped to directly image has been captured by NASA's James Webb Space Telescope's Near-Infrared Camera (NIRCam). In this stunning image of the Serpens Nebula, the discovery lies in the northern area of this young, nearby star-forming region.
Published Geologists expect Chang'e-6 lunar surface samples to contain volcanic rock and impact ejecta
(via sciencedaily.com) Original source On June 25, China's Chang'e-6 (CE-6) lunar probe is set to return to Earth, carrying the first surface samples collected from the farside of the Moon. In anticipation of this historic event, scientists are publishing their predictions for the unique materials that may be found in the CE-6 samples.
Published A hidden treasure in the Milky Way -- Astronomers uncover ultrabright x-ray source
(via sciencedaily.com) Original source Astronomers uncovered that a well-known X-ray binary, whose exact nature has been a mystery to scientists until now, is actually a hidden ultraluminous X-ray source.