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  1. Hubble Has Found the Ancient Galaxies That Gave the Universe Its First Light The Abell 2744 galaxy cluster Credit: NASA/ESA/Hubble A new technique that removes the light of foreground galaxy clusters is giving astronomers a direct look at a generation of galaxies dating back to the universe's baby years. The discovery is considered a key piece of evidence for a critical, but poorly understood period of time when the universe switched from being dark to radiating light. Scientists theorize that energy from first-generation galaxies transformed the dark, electrically neutral universe into ionized and radiating plasma. But these faint galaxies are not easy to find. This week, University of Texas astronomer Rachael Livermore and colleagues describe a successful hunt thanks to a new technique that combines deep-field Hubble Space Telescope images with what is known as "wavelet decomposition" — a light-masking equivalent of noise-canceling headphones — to computationally remove light from foreground galaxy clusters. "The wavelet transform allows us to decompose an image into its components on different physical scales. Thus, we can isolate structures on large scales… and remove them, allowing objects on smaller scales to be identified more easily," the scientists wrote in a draft of their upcoming paper, published on arXiv.org. The MACS 0416 galaxy cluster as seen by Hubble as part of the Frontier Fields project. Credit: ESA/NASA/Hubble Ironically, astronomers first have to rely on galaxy clusters, which warp spacetime with their massive gravity, to serve as naturally occurring lenses that boost Hubble's resolving power more than 100 times. By then masking the light, Livermore, University of Texas astronomer Steven Finkelstein and Space Telescope Science Institute astronomer Jennifer Lotz found 167 galaxies that are 10 times fainter than any previously known, a number that shows "strong support" for how many early galaxies would have been needed to re-ionize the universe. A more direct detection method will come after Hubble's successor, the James Webb Space Telescope, is launched next year. http://www.space.com/35668-hubble-frontier-fields-lensing-astronomy-universe-ancient-galaxies.html
  2. Phantm

    A Strange Green Comet Is Heading Our Way

    You gotta aim a little better.
  3. A Strange Green Comet Is Heading Our Way Comet 45P/Honda-Mrkos-Pajdušáková. Credit: NASA/JPL An unusual green comet reaches maximum brightness on Saturday, providing a sweet treat for early-morning risers. Comet 45P/Honda-Mrkos-Pajdusakova (named after three astronomers who discovered it in 1948) travels into the inner solar system every 5.25 years. On Saturday, 45P will pass just 7.4 million miles from Earth, a stone's throw by celestial yardsticks. With binoculars or a small telescope, comet-watchers should be able to spot 45P in the pre-dawn skies between Thursday and Sunday. "The comet will be racing through the constellation Hercules high in the eastern sky," notes SpaceWeather.com. Comet 45P will look like fuzzy bluish-green ball with a fan-shaped tail. Its distinctive color comes from vaporizing diatomic carbon, a gas which glows green in the near-vacuum of space. The Minor Planet Center reports 45P's upcoming pass as the eighth closest comet since modern tracking technologies began around 1950. It made an even closer approach during its last visit in 2011, pictured above, but it won't be as near to Earth again this century. "Proximity makes the comet bright despite its small size," said SpaceWeather.com. "Forecasters say 45P could be on the verge of naked eye visibility… when it emerges into the pre-dawn sky later this week." http://www.livescience.com/57822-strange-green-comet-heading-our-way.html
  4. Primeval Reservoirs Under Earth's Mantle May Be Older Than the Moon Matthew Jackson takes a sample of lava from a flow in Hawaii. New research suggests that this lava may contain traces of a primeval Earth that dates back 4.5 billion years. Credit: WHOI Geodynamics program Lava from Earth's hottest spots may be flecked with primordial rock that existed 4.5 billion years ago, before the moon had formed, new research suggests. The traces of ancient Earth likely come from dense primordial reservoirs buried deep below the Earth's surface, at the boundary between the mantle and the core. As plumes of molten rock in the Earth's mantle rise toward the surface, they pull in some of this primeval rock. These plumes then warm Earth's surface at volcanic hotspots, oozing lava that contains signatures of the young planet, according to the study, which was published on Monday (Feb. 6) in the journal Nature. "We're finding the hottest plumes are sampling the oldest domains on the Earth," said study co-author Matthew Jackson, a geochemist at the University of California, Santa Barbara. "These lavas are sampling a domain in the Earth that had to have formed in the first 100 million years of Earth's history." Smashing beginning Around 4.54 billion years ago, Earth formed during several massive collisions, the last of which occurred about 100 million years after the solar system's coalescence, when Earth crashed into the planetoid Theia. The vaporized remains of this planetoid then condensed to form the moon. Though the violent churning of the Earth has erased almost all traces of this early history, in the past few decades, scientists have found evidence that bits of this young Earth may still exist in places like Hawaii and Iceland. These locations are among the 50 volcanic hotspots on the planet, where heat from the Earth's mantle rises in a plume, melting rock at the base of the tectonic plates that form Earth's surface. The molten rock, or magma, then oozes through fissures in the Earth to erupt and form volcanoes. In the 1980s, scientists sampling lava in Hawaii noticed that in some spots, the ratio of helium-3 (helium with just one neutron per atom) to the version with two neutrons per atom, called helium-4, was higher than expected based on the surrounding rock's composition. "This ratio is associated with the building blocks of the planet, primitive meteorites, the atmosphere of Jupiter, the solar wind," Jackson said. (Jupiter's atmosphere likely formed early in the solar system's history.) In other words, the high ratio of helium-3 to helium-4 suggested a very ancient source, he said. Follow-up studies produced ratios of other isotopes, such as tungsten and xenon, that suggested these lavas may come from the first 50 million years of Earth's history. "It records the earliest history of the planet," Jackson told Live Science. Hottest spots, oldest rock However, only some hotspots held lava with high helium-3/helium-4 ratios. Why then were some hotspots sampling this primordial soup when others weren't? To answer that question, Jackson and his colleagues took helium-isotope data from 38 volcanic hotspots around the world and combined that information with data on how fast seismic waves travel through the upper mantle. Seismic waves travel more slowly through hotter mantle. They found that the areas with the slowest seismic waves (and therefore the hottest mantle) also had a helium signature associated with primordial reservoirs. The new research suggests that the hottest of hotspots may be the only ones pulling from this primordial pool of ancient rock, the study said. The hottest spots are likely fed by the most buoyant plumes in the mantle, meaning the plumes are better able to rise up in relation the surrounding mantle rock, the researchers said. These ultrahot plumes are also able to cause more melt, the scientists added. Under this hypothesis, these dense blobs of primordial rock lie about 1,860 miles (3,000 kilometers) below the Earth's surface, at the boundary with the core. Because these blobs are so dense, only the hottest mantle plumes can melt bits of this material and transport it, Jackson said. The high density "also explains how something so ancient could survive in the chaotically convecting mantle for 4.5 billion years," he said in a statement. "The density contrast makes it more likely that the ancient helium reservoir is preserved rather than mixed away." While the findings suggest an explanation for why only some lava contains traces of ancient Earth, the results don't answer larger questions about these primeval reservoirs, Jackson said. For instance, scientists have little idea what these primordial reservoirs are made of or how they formed, he said. http://www.livescience.com/57809-earth-mantle-is-older-than-the-moon.html
  5. Newfound Gecko Species Jumps Out of Its Own Skin When grasped by a predator, fish-scale geckos lose not just their scales but also the skin underneath. This bizarre behavior could be important in helping them to escape. Credit: Frank Glaw A newly discovered species of gecko with unusually large scales practices a bizarre defensive strategy that might make your skin crawl: When a predator catches hold, the gecko literally jumps out of its own skin. The species, Geckolepis megalepis, was described recently in a new study. Part of a small group known as fish-scale geckos, these creatures have scales that are larger than those of any known gecko species, the researchers said. Each scale can be as large as 0.2 inches (5.8 millimeters) — about 8 percent of the gecko's body length — and those big scales could make the gecko especially adept at escaping predators, according to the new study. Whereas most geckos have small scales that lie flat against their bodies, fish-scale geckos have large, overlapping scales that are only partly attached to their skin. But what is really unusual about this genus of geckos is the layer of skin beneath those scales, which tears away easily and grows back quickly, according to the study's lead author, Mark Scherz, a doctoral candidate at Ludwig Maximilian University of Munich and Zoologische Staatssammlung München (the Bavarian State Collection of Zoology). "Their skin has this pre-formed zone for shearing and an unusually fast regeneration cycle," Scherz told Live Science in an email. Prior studies of fish-scale geckos noted that these animals can completely regrow their scaly coverings in just a few weeks. The new fish-scale gecko, Geckolepis megalepis, has the largest body scales of all geckos. Credit: Frank Glaw G. megalepsis geckos are native to Madagascar, and measure up to 2.8 inches (7 centimeters) in length, from the tip of the snout to the base of the tail, the researchers wrote in the study. The geckos' oversize scales create a pebbly texture in mottled shades of brown and cream. But after a close encounter with a predator, the denuded geckos' bodies become shiny and pink where their scaly covering has ripped away. There is no blood or scarring, and the scales that grow back are almost indistinguishable from the original scales, Scherz said. Capturing any small wild animal for scientific analysis can be extremely challenging, but it is even more difficult if the animal is likely to drop its skin when touched, Scherz said. So how do scientists catch these geckos without causing them to shed their scales? Very, very carefully, Scherz told Live Science. "Generally, what we do is lure the geckos into a container or plastic bag, so that we have the minimum possible contact with them," Scherz said. "It is possible to catch them by hand without losing scales, but it takes a lot of practice and is not always successful." Scherz and his colleagues caught three G. megalepsis specimens in northern Madagascar's Ankarana Reserve. The size, shape and distribution of its scales, as well as subtle distinguishing features in its skeleton, revealed to the study authors that it was a new species. Skull renderings of the new gecko species from micro-CT scans. Credit: Mark D. Scherz The unusual size of its scales — "considerably larger than any other species," Scherz said — was especially interesting to them. Previous studies of fish-scale geckos, as well as the new study's analysis, show that these types of scales are dense and highly mineralized. Growing them comes at some metabolic cost to the animal, which makes it puzzling that their main defense involves losing the scales so easily, Scherz said. "Whatever the cost of regenerating the scales, it cannot be as great as losing your life to a predator," Scherz said. "So even when the cost could be enormous, it is worth it. That's an interesting evolutionary strategy." Studying the scale-shedding geckos more closely could even inform medical research, he added. Understanding how the geckos' regenerated scales grow back without forming scars could assist scientists in developing techniques for minimizing or eliminating scarring during skin repair. http://www.livescience.com/57786-new-gecko-species-disposable-skin.html
  6. Huge Undersea Landslide Slammed Great Barrier Reef 300,000 Years Ago A view of the Gloria Knolls Slide off Queensland, Australia. Colors represent the depth of the features beneath the water surface, from red (shallow) to blue (deep), with the greatest depth reaching about 5,600 feet (1,700 meters). Credit: www.deepreef.org More than 300,000 years ago, a colossal undersea landslide sent huge amounts of debris sliding down the Great Barrier Reef, generating a 90-foot-high (27 meters) tsunami, researchers have discovered. Perhaps luckily for creatures in the area, that tsunami wave would have been dampened by the surrounding reefs, the researchers said. The slide would have sent about 7.6 cubic miles (32 cubic kilometers) of rubble plunging down a slope of the Australian reef. (For comparison, the volume of the Great Pyramid of Giza is about 91 million cubic feet, or less than one-100th of a cubic mile. That means a volume of some 12,000 Great Pyramids plunged to the seafloor during the prehistoric landslide event.) The culprit of the slide? "We believe an earthquake of sufficiently large magnitude was the most likely trigger for such a landslide event," study researcher Robin Beaman of James Cook University in Queensland, Australia, told Live Science in an email. "As for, 'Would a similar phenomenon happen today?' the continental slope sediments appear stable under current conditions." The researchers discovered the remnants of the giant submarine landslide while mapping the seafloor along a margin of the Great Barrier Reef using 3D multibeam sonar, in which sound waves are bounced off the seafloor. In one spot, called the Queensland Trough, which was supposed to be relatively flat, they found eight knolls, some of which rose 330 feet (100 meters) above the seafloor with lengths of more than 9,800 feet (3,000 m), the researchers said. That series of knolls, now called the Gloria Knolls Slide complex, were the result of the ancient landslide, the researchers found. Their geological sleuthing involved more seafloor mapping and coral sampling. Samples from the knolls, which were submerged under nearly 4,000 feet (1,200 m) of water, revealed both living and fossil corals, Beaman said. The corals took up residence along the knolls sometime after the hilly terrain formed. "The oldest fossil coral we found, using isotope dating techniques, was 302,000 years old, therefore, making the landslide event that caused these knolls to be older than that age," Beaman told Live Science. From the detailed, 3D maps of the area, the researchers reconstructed, or modeled, the landscape that would have existed before the slide. "So we can then simply do a before/after analysis of the volume of sediment that has been removed from this pre-slide surface," Beaman wrote. The research, detailed in the March 2017 issue of the journal Marine Geology, was conducted by Beaman, lead author Angel Puga-Bernabéu of the University of Granada, Jody Webster of the University of Sydney, Alex Thomas of the University of Edinburgh, and Geraldine Jacobsen of the Australian Nuclear Science and Technology Organization. The researchers noted that more research is needed to determine the risk of tsunamis related to these types of underwater landslides on the Queensland coast. http://www.livescience.com/57799-massive-undersea-landslide-off-australia-found.html
  7. World’s most endangered marine mammal has 30 individuals left Illegal, but still happening Flip Nicklin/Minden Pictures/National Geographic Creative The world’s smallest porpoise is in dire straits. Only 30 individuals of the vaquita porpoise are left on the planet. The population of vaquitas has dramatically dwindled since 2011. Between 2015 and 2016, almost half the remaining vaquitas died, and over the past five years, their numbers have decreased by a total of 90 per cent. Vaquitas live exclusively in a small area in the Gulf of California, Mexico, where illegal fishing with gill nets is the main cause of their demise. Gill nets are commonly used by fishermen targeting the totoaba, another endangered species sought after in Asia for the supposed medicinal properties of its swim bladder. “They’re essentially taking out two endangered species in one fell swoop,” says Kate O’Connell, a marine wildlife consultant at the Animal Welfare Institute. “We know what the problem is: it’s gill nets. We’ve known for 30 years that gill nets kill vaquita and we have done nothing, and I find that heartbreaking.” Porpoise in peril In 2015, the Mexican government enacted a two-year ban on gill nets that covers the home territory of the vaquita, but the law is not well enforced. A recent report by the International Committee for the Recovery of the Vaquita (CIRVA) detailed 31 illegal gill nets in the range of the vaquita during a 15-day survey of the region in October and November 2016. The ban also included a loophole that allowed gill nets to be used to catch corvina in legal fisheries, which makes it possible for the nets to disguise illegal totoaba fishing. “As long as that loophole is there it’s unlikely we can do much to protect the vaquita,” O’Connell says. “We need a permanent ban on gill nets in the upper Gulf of California.” The temporary ban is set to end in April and it’s unclear whether it will be extended, O’Connell says. To protect the vulnerable vaquita, CIRVA recommends a permanent ban on gill nets and stronger enforcement of illegal gill net fishing. They also suggest that some vaquitas should be placed in a temporary sanctuary, though there has never been an effort to capture them and it’s unclear how they would respond to captivity. O’Connell says that other marine mammal species have come back from extremely low numbers, including the northern elephant seal, which was nearly wiped out in the 19th century and has rebounded from less than 100 individuals to well over 100,000 today. Saving the species CIRVA also suggests that some vaquitas should be placed in a temporary sanctuary, and though most porpoises respond well to being captured, there has never been an effort to catch vaquitas so it’s unclear how they would respond to captivity. Barbara Taylor at the National Oceanic and Atmospheric Administration says there’s a plan in place to catch some vaquitas as early as October 2017 and house them in captivity until it’s safe to return them to their natural habitat. “We can’t afford to wait anymore. They’re going to be gone in a year or two,” she says. It will be tricky to catch the vaquitas because they’re shy and tend to avoid humans and boats. The water they live in is fairly cloudy and on average vaquitas only gather in groups of a few animals. They’re so rare, Taylor says, “a lot of fishermen still maintain to this day that they’re mythical.” To track these elusive creatures, researchers use a grid of acoustic monitors embedded in the sea floor to monitor the population size. “Porpoises are compulsive echo-locators … they find their food by echo-locating like bats,” she says. Comparing the number of echolocation clicks heard underwater year-by-year gives researchers a good idea of how many individuals are left in the wild. Dolphin posse Because they’re tough to spot even with high-powered binoculars and expert observers, the round-up crew will use trained dolphins from the US Navy Marine Mammal Program to help find the vaquitas in the murky waters. Dolphins are easier to spot and approach with boats, so Taylor says the researchers can follow them to the elusive porpoises. But the most difficult challenge is the race against time. Taylor says a successful expedition to capture the vaquitas requires funding, housing and veterinary care, as well as perfectly clear weather that won’t be available until after winter is over. “Right now the clock is ticking, and we’re not winning,” she says. https://www.newscientist.com/article/2120188-worlds-most-endangered-marine-mammal-has-30-individuals-left/
  8. An unexplained 'void' appears to be pushing the Milky Way through the Universe at 2 million km/h We're fleeing from a mysterious 'dead zone'. You can’t feel it, but our planet is orbiting the Sun at speeds of roughly 100,000 km/h (62,000 mph), and something is making our Milky Way galaxy move through the Universe at more than 2 million km/h (1.2 million mph). That’s 630 km per second, and now scientists might have finally figured out why. In front of us, there's a dense supercluster of galaxies some 650 million light-years away called the Shapley Concentration, and it's pulling us towards it. Behind us, scientists have found evidence of a previously unknown region of space that's almost entirely devoid of galaxies, and it's pushing us away with incredible force. Cosmologist Yehuda Hoffman from Hebrew University in Israel and his team have constructed a new 3D map of our nearest galaxies, and in it, they’ve revealed this mysterious 'dead zone' for the first time, and dubbed it the Dipole Repeller. "By 3D mapping the flow of galaxies through space, we found that our Milky Way galaxy is speeding away from a large, previously unidentified region of low density. Because it repels rather than attracts, we call this region the Dipole Repeller," Hoffman explains to Victoria Woollaston at Wired. "In addition to being pulled towards the known Shapley Concentration, we are also being pushed away from the newly discovered Dipole Repeller. Thus it has become apparent that push and pull are of comparable importance at our location." In the past, researchers have suggested that a very low-density region of space could be lurking behind our galaxy, because while the Shapley Concentration is incredibly massive, on its own, it can't explain that speeds that the Milky Way is travelling. And that really says something, because the Shapley Concentration is the largest known concentration of matter in the local Universe - a region of space that's approximately 1 billion light-years in radius. The only problem is, we can barely even detect a planet that's 4.25 light-years away, let alone find something that's millions of light-years away, so researchers have struggled to fit that piece of the puzzle together. "There was a hint of the void from studies of the distribution of rich clusters of galaxies that emit X-rays, discussed in articles over a decade ago," one of the team, Brent Tully from the University of Hawai'i, says in a press statement. "But the statistics were not sufficient to be convincing." But now Hoffman and his team have figured out how measurements from more than 8,000 nearby galaxies, taken from an array of observatories, including the Hubble Space Telescope, fit into our cosmic neighbourhood, and these movements give us the first real evidence of the great Dipole Repeller. All those forces combined look a little something like this: Yehuda Hoffman, et. al Oddly enough, according to data from the Cosmic Microwave Background - the 'afterglow' of the Big Bang - these two forces appear to be pushing and pulling us with an equal amount of force, and they sit in front and behind the Milky Way on the same axis. Now that we have the first real evidence that something as vast and empty as the Dipole Repeller is lurking behind the Milky Way and our neighbouring galaxies, the next step is for researchers to try and confirm its existence. The other possibility is that this region could be not one, but a whole fleet of superclusters and voids, all working to buffet us away, as another, more massive supercluster draws us in. As Hoffman told Ian Sample at The Guardian, "It’s a story of love and hate, attraction and repulsion." http://www.sciencealert.com/an-unexplained-void-is-pushing-the-milky-way-through-the-universe-at-2-million-km-h
  9. Researchers just found evidence of an ancient 'lost continent' under Mauritius Earth still has some massive secrets. Newly discovered crystals expelled from volcanic eruptions on the island of Mauritius are billions of years older than the island itself, and are thought to be the remnants of an ancient microcontinent known as Mauritia. The proposed 'lost continent' would have once connected Madagascar and India in the Gondwana supercontinent, but likely disappeared into the Indian Ocean around 84 million years ago. Now researchers have found what appears to be a piece of Mauritia, dredged up by ancient volcanoes and hidden below the surface. "Earth is made up of two parts - continents, which are old, and oceans, which are 'young'," says one of the team, Lewis Ashwal from the University of the Witwatersrand in South Africa. "Mauritius is an island, and there is no rock older than 9 million years old on the island. However, by studying the rocks on the island, we have found zircons that are as old as 3 billion years." The island of Mauritius is located about 2,000 kilometres (1,200 miles) off the southeast coast of the African continent. Thought to be a relatively new landmass, the island was formed by gigantic underwater volcanic eruptions between 8 and 9 million years ago, and now belongs to the Mascarene Islands archipelago, along with the Saint Brandon, Réunion, and Rodrigues islands. Ashwal and his team dug up the piece of crust from a rocky outcrop in Mauritius that had been covered by molten lava during volcanic eruptions at the time of the island’s formation. When they analysed the material within, they found tiny zircon crystals that were billions of years older than the landmass itself. The fact that the crystals were made from zircon - a common gemstone that can come in colourless, yellow, red, brown, blue, and green hues - was enough to tip off the researchers that what they were looking at did not come from the ocean below. One of the zircon crystals. Credit: University of the Witwatersrand Zircons are known to form mainly from the granites of ancient continents that once spread across Earth’s surface, and once the team dated the crystals to between 2.5 and 3 billion years, they say it's a strong indication that they belonged to the long-lost continent of Mauritia. "The fact that we have found zircons of this age proves that there are much older crustal materials under Mauritius that could only have originated from a continent," says Ashwal. This isn’t the first time that ancient zircons have been found on the island of Mauritius - back in 2013, a separate team found traces of zircon in beach sand that were also billions of years old. But the find was controversial, because critics argued that these minerals could have blown onto the beach from elsewhere. Now that we have similar crystals that were buried by ancient lava deposits, scientists can make a much stronger case for them being the remains of a lost continent. "The fact that we found the ancient zircons in rock corroborates the previous study, and refutes any suggestion of wind-blown, wave-transported, or pumice-rafted zircons for explaining the earlier results," says Ashwal. The find now paints a picture of an ancient continent being splintered into fragments, some of which ended up being anchored below the current landmass that makes up the island of Mauritius today. It also explains the mystery of why some parts of the Indian Ocean have been found to have stronger gravitational fields than others - a potential indication of thicker crusts. It’s expected that more chunks of the ancient Gondwana supercontinent will be dredged up in the coming years. As Alice Klein reports for New Scientist, several pieces of continent have recently been found off the coast of Western Australia and underneath Iceland. "It’s only now as we explore more of the deep oceans that we’re finding all these bits of ancient continents around the place," Martin Van Kranendonk from University of New South Wales in Australia, who wasn’t involved in the study, told Klein. http://www.sciencealert.com/researchers-just-found-evidence-of-a-lost-continent-under-mauritius
  10. Phantm

    Yoo...Bro's

    Hi speedbrain. Welcome to CyberPhoenix. Enjoy the site.
  11. Phantm

    Hi

    Hi bagdal. Welcome to CyberPhoenix. Enjoy the site.
  12. An expedition to search for Antarctica's 'lost meteorites' has been approved What's hiding below the ice? Antarctica should be the perfect place to find meteorites - the dark rocks are easy to spot against the ice-covered landscape, and upward-flowing ice regularly dumps buried meteorites onto the surface. But, oddly enough, relatively few iron-based meteorites have ever been found on the continent, leading scientists to suspect that something is causing them to get lost beneath the ice. Now, an expedition has been green-lit to go and look for them. If the team, funded by the British Antarctic Survey, can find some of these iron-based meteorites, it could give us crucial clues about how life got started on our planet, and how the rest of the Solar System formed. "We now have the opportunity to commence on a truly exciting scientific adventure," said expedition leader Geoffrey Evatt, a mathematician from the University of Manchester. "If successful, our expeditions will help scientists to decode the origins of the Solar System." Iron meteorites are so interesting to researchers because they're formed from the cores of planetesimals - small planets in the early days of the Solar System that went on to be destroyed by further planetary impacts. Getting a better understanding of their composition and age can tell scientists a lot about how planets are formed, and how the Solar System evolved. But that's if they can find them. Two-thirds of the world's meteorites have been found in Antarctica, many of them in areas of glacial ice known as meteorite stranding zones, which force meteorites to the surface with regular uprisings of ice. But back in 2012, Evatt worked with glaciologists to show that iron meteorites have been conspicuously missing from those discoveries. In fact, only 0.7 percent of the meteorites collected from the meteorite stranding zones are iron-based - compared to 5.5 percent of the meteorites collected from the rest of the world. "Meteorite collection data shows that iron and stony-iron meteorites are significantly under-represented from these regions as compared with all other sites on Earth," Evatt and colleagues wrote in a paper in Nature Communications last year. The team hypothesises that the iron meteorites are getting heated up by sunlight in Antarctica as a result of their metallic content, and melting the ice surrounding them. This then causes them to sink and get trapped below the surface. They concluded that the meteorites are most likely hidden as a sparsely distributed layer, just a few centimetres beneath the surface of the Antarctic ice - which means they wouldn't be that hard to retrieve, but have been masked from previous meteorite-hunting expeditions. Their approved mission proposal will use new technology based on metal-detectors to scan for the hidden meteorites. The team will test the technology next year on the Arctic island of Svalbard, and make a preliminary visit to Antarctica in 2019. The main expedition is expected to take place in early 2020, when the researchers will find out if their hypothesis is correct. "The whole notion of a layer of missing meteorites in Antarctica came out of blue-sky discussions at an interdisciplinary workshop, between a group of applied mathematicians and glaciologists, back in 2012," said Evatt. "Having subsequently turned those initial ideas into firm scientific reasoning, we now have the opportunity to put our mathematical hypothesis to the most extreme of tests." Until they get down there, there's no way of knowing where Antarctica's missing meteorites are hiding - or if they're even there at all. But seeing as we can learn so much from them, we're glad scientists will soon get the chance to find out. http://www.sciencealert.com/an-expedition-to-search-for-antarctica-s-lost-meteorites-has-been-approved
  13. Giant Otters Used to Be Fearsome Hunters in Ancient China A prehistoric was otter revealed to be two times larger than today’s South American giant sea otter and four times larger than the Eurasian otter. (Photo : Alex Wong/Getty Images) Six million years ago, massive otters roamed the Earth armed with powerful jaws and very big skulls. This image is a far cry from the adorable creatures that otters are known for being now, but new research revealed they used to be a lot more fearsome than the world gives them credit for. According to a report from Live Science, scientists unearthed a 6.2 million year old fossil that turned out to be the largest otter ever on record. This impressive animal was revealed to be two times larger than today's South American giant sea otter and four times larger than the Eurasian otter. The fossil was discovered back in 2010. It was nearly a complete skull when Chinese and American scientists found it in the Shuitangba quarry in southwestern China. Lead researcher of the study Xiaoming Wang explained that this prehistoric otter - now extinct - is bigger than all of the other otter species that survived. Wang is also a curator of vertebrate paleontology at the Natural History Museum of Los Angeles County in California. "The skull was unlike [that of] any other animals found so far, and that's when we realized that this is something unique and important," he added, then shared the challenges that came with the millions-year-old remains. "Because the skull was preserved in soft brown coal, it has been badly crushed into a pancake-like shape during the compaction of soft sediments." In 2015, additional bones of the same species were found in the quarry. These included lower jaws, limbs and teeth. Eventually, the team was able to piece together the arts and create a more complete picture of what they call the "obscure" species. Named the Siamogale melilutra, the extinct otter was part of one of the most primitive lineages that can be traced to at least 18 million years ago. Interestingly enough, the size of this animal is somewhat surprising as many carnivores that evolve to be this large did so to subdue prey. Instead, the S. melilutra ate mollusks, although their powerful jaws were probably useful in cracking clam shells. Modern otters use tools like sharp rocks, but their ancient cousins may have been able to feed without extra help. http://www.natureworldnews.com/articles/35175/20170123/giant-otters-used-fearsome-hunters-ancient-china.htm
  14. Early Meteorite Bits Reveal Clues About Solar System's Evolution More than 460 million years ago, a massive solar-system collision generated many of the meteorites still falling to Earth. Now, researchers are probing the meteors that came before that event. Credit: Don Davis, Southwest Research Institute Many meteorites found on Earth are remnants of one titanic solar-system collision that took place more than 460 million years ago. But for the first time, researchers have specifically targeted meteorites that fell to Earth just before that asteroid collision and found that the composition of those earlier space rocks is quite different than those today. By sifting through the minuscule remnants of those ancient solar-system crashes, called micrometeorites, the researchers found that the most common types of meteorites today used to be quite rare — and the rarest ones used to be common. Understanding the makeup of asteroids provides insight into the history of solar-system collisions and the evolution of the asteroid belt between Mars and Jupiter, scientists say. "We spend lots of time studying the debris from the big asteroid destruction event 466 million years ago, but recently, we went a little bit further back in time," said Philipp Heck, a researcher at The Field Museum in Chicago and lead author of the new research paper. "We found it very different from what comes down today — that was our big surprise," Heck told Space.com. Meteorites come from flying debris after a collision of two bodies in the solar system, and their makeup reflects the asteroid, comet, moon or planet that suffered through the crash. The rarest meteorites found on Earth today come from differentiated or partially differentiated bodies — big clusters of dust and debris that got hot enough to form (or partially form) a core, mantle and crust, as on Earth, Mars or the asteroid Vesta. It's much more common for meteorites today to come from undifferentiated bodies, which remained mixtures of rock, dust and metal. But according to the new research, that type of meteorite, called an ordinary chondrite, used to be much less common than ones from differentiated bodies were. By avoiding the most recent meteorites, researchers can get a glimpse of more collisions in the solar system's past. "This is not an event, what we're looking at — this is basically the background," Heck said. "You can say these are tails of different events; the results of different [collision] events in the solar system, in the asteroid belt, that generated fragments … and those fragments arrived to Earth." A few events and asteroid populations seem to dominate that background, he added: 34 percent of the micrometeorites came from partially differentiated bodies, which had partially melted and begun to separate out, whereas only 0.45 percent of meteorites today are that type. This indicates that many more of those bodies were experiencing collisions in the past, Heck said. The researchers also found micrometeorites that originated from a collision at Vesta, the brightest asteroid visible from Earth, billions of years ago, as well as meteorites that the researchers think came from the formation of the Flora asteroid family, also about a billion years ago. Both reside in the asteroid belt. Notably, there were very few ordinary chondrites — most were generated later, by the 466-million-year-old collision or by an even later event, which generated another type of ordinary chondrite, Heck said. A false-color image taken by an electron microscope of a polished cross-section of chrome spinel. The mineral was taken from a fossil micrometeorite that likely came from the asteroid 4 Vesta. Credit: Philipp Heck/The Field Museum "Using relict minerals in the rock record to determine the previous asteroid flux is incredibly inventive," Tasha Dunn, a planetary geologist at Colby College who was not involved in the research, told Space.com by email. "I was quite surprised by the results." Dunn noted that the proportions of meteorite types that rain down today don't match the populations of asteroids found in the belt — a disparity that has puzzled meteorite researchers. "Trying to understand why the proportion of asteroids in the asteroid belt doesn't match what we see in the meteorite collection has been one of the biggest questions in meteorics for some time," she said. Dunn said she was particularly interested in seeing the large proportion of meteorites from the Flora family back then, because researchers have wondered why there weren't many of them coming down despite the Floras' good position. Maybe, she said, much of the material was expelled during the initial breakup of the family. "Needle in a haystack" Understandably, meteorites that fell more than 466 million years ago are difficult to find. Heck's Russian and Swedish colleagues turned to micrometeorites less than 2 millimeters (0.08 inches) across. By sifting through samples of rock from a river valley in Russia that used to be seafloor, they managed to separate some. They chose a location that would have had a slow buildup of sediment, leading to a greater proportion of the desired micrometeorites. The researchers took advantage of a lucky fact: chromites and chrome spinels, the key grains necessary to determine the age and makeup of a micrometeorite, are resistant to acid. So to find the meteorite compounds, they treated the material with hydrochloric or hydrofluoric acid to eat away the Earthly sediments, leaving the meteorite markers behind. "The approach is essentially a needle-in-a-haystack problem, and we use the crude method of burning down the haystack to find the needle," Heck said. Heck's group analyzed samples dating back from the target era, zeroing in on the chromites and chrome spinels whose makeup can help scientists classify the type of object they came from. "Even almost 500 million years in the sediment didn't change them," Heck said. "They still preserve the original composition, which makes it a really, really good and robust mineral to study meteorites that arrived in the past." They also measured the oxygen isotopes — that is, oxygen with different numbers of neutrons — whose proportions likely represent how far from the sun the body formed, Heck said. Going forward, Heck said, researchers should look at different time windows to try to understand those earlier solar system collisions, like the one that blasted fragments off of Vesta. "We can do that for the different types of fragments from different parent bodies, parent asteroids, and get a better picture of what collisions happened and what were the effects on planets in the inner solar system," he said. One could also track meteorite fragments on places like the moon and Mars for a more complete view. All results can be fitted into models of the events, increasing their accuracy and our understanding of the solar system's evolution — and, potentially, those titanic crashes' impact on Earth's life and climate. "It's really a multidisciplinary collaboration with different fields — geology, cosmochemistry, planetary science, chemistry — all working together to try to tackle that problem," Heck said. http://www.livescience.com/57625-early-micrometeorites-illuminate-solar-system-evolution.html
  15. Earth from Space: New 'Blue Marble' Photo Is Jaw-Dropping The Earth as a "full disk" from the view of NOAA's new weather satellite, GOES-16. Credit: NOAA/NASA A new weather satellite has relayed its first images of Earth back to scientists, and the new collection, which includes an updated version of the iconic "Blue Marble" image of Earth, is simply stunning. The satellite, dubbed GOES-16, is designed to snap high-definition images of the continental United States every 5 minutes and the full Earth every 15 minutes, according to the National Oceanic and Atmospheric Administration (NOAA). These photos will help meteorologists monitor weather patterns with greater precision. In its first publicly released set of images, GOES-16 captured the planet in intricate detail. From storm systems over North America to the dust-laiden air from the Sahara over Africa, the satellite is already giving scientists a new perspective of the Earth. "One of our GOES-16 scientists compared this to seeing a newborn baby's first pictures — it's that exciting for us," Stephen Volz, director of NOAA's Satellite and Information Service, said in a statement. One of the striking images is a new "Blue Marble" photograph of the Western Hemisphere. The so-called full disk image shows North America and South America and the surrounding oceans with swirling white clouds overhead. From 22,300 miles (35,900 kilometers) above Earth, GOES-16 will not only improve the precision of forecasts but also add to Earth's overall weather observation network, NOAA researchers said. GOES-16's updated instruments will enable it to take photographs with an image resolution four times higher than those taken by existing GOES spacecraft, the agency added. "These images come from the most sophisticated technology ever flown in space to predict severe weather on Earth," Volz said. "The fantastically rich images provide us with our first glimpse of the impact GOES-16 will have on developing lifesaving forecasts." In May, NOAA is expected to announce the location of GOES-16's geostationary orbit, and by November, the satellite will be operational for weather forecasting, according to agency officials. http://www.livescience.com/57599-spectacular-earth-photos-goes-16-satellite.html
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