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  • richardmitnick 1:53 pm on September 14, 2019 Permalink | Reply
    Tags: "Study Reveals Lost Continent Demolished by Europe", , Greater Adria, , Smithsonian.com,   

    From smithsonian.com: “Study Reveals Lost Continent Demolished by Europe” 

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    From smithsonian.com

    Painstaking research recreates the history of Greater Adria, which slipped under the Eurasian plate 120 million years ago.

    September 13, 2019
    Jason Daley

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    Remnants of Greater Adria in the Taurus Mountains (Utrecht University)

    Researchers uncovered traces of a lost continent that disappeared under what is today Europe about 120 million years ago.

    Geologists have seen hints of the continent, dubbed Greater Adria, for years. But the Mediterranean area is incredibly complicated, so piecing together its history took a decade of academic detective work. “The Mediterranean region is quite simply a geological mess,” geologist Douwe van Hinsbergen of Utrecht University, first author of the study in Gondwana Research says. “Everything is curved, broken, and stacked.”

    The story that the rocks tell begins on the supercontinent Gondwana, which would eventually split into Africa, South America, Australia, Antarctica and India. Greater Adria broke away from the mother continent about 240 million years ago, beginning a slow drift northward. Roughly 140 million years ago, it was about the size of Greenland, mostly submerged in a tropical sea, collecting sediment that hardened into rock. Then, roughly 100 to 120 million years ago, it hit the southern edge of future Europe, spinning counterclockwise and moving at about 3 to 4 centimeters per year.

    As Robin George Andrews at National Geographic reports, the destruction of Greater Adria was complex. It hit several subduction zones, or areas where tectonic plates meet. In this case, the Greater Adria plate was trumped by the European plate, and most of it dove down into Earth’s mantle. The overlying plate scraped the top layers of Great Adria off. That debris eventually formed mountain ranges in Italy, Turkey, Greece, the Balkans and in the Alps. A few bits of Greater Adria escaped the plunge into the mantle and still exist in Italy and Croatia.

    Figuring out the story of Greater Adria was difficult, not only because of the geology but also due to human factors. Information about the continent is spread across many countries, from Spain to Iran. “Every country has their own geological survey and their own maps and their own stories and their own continents,” Hinsbergen tells Yasemin Saplakolu at LiveScience. “[With this study] we brought that all together in one big picture.”

    They also spent time constructing the continent’s history by examining the orientation of tiny magnetic minerals created by bacteria trapped in the Adria rocks. From that data they were able to understand how much the rock layers rotated over time. They also pieced together structures like strings of volcanoes and coral reefs. New, more powerful software developed over the last 15 years or so also aided in reconstructing the lost land mass.

    Sid Perkins at Science reports that the new study isn’t the only evidence for Greater Adria. In 2016, another team identified slabs of the continent in Earth’s mantle using seismic waves. Nor is it the only “lost continent” out there. A large land mass called Zealandia is submerged under two-thirds of a mile of water in the South Pacific and is considered the “eighth continent” by some researchers. In 2017, other scientists announced that they found a sunken “mini-continent” under the island of Mauritius in the Indian Ocean.

    See the full article here .

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    Please help promote STEM in your local schools.

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  • richardmitnick 10:44 am on September 7, 2019 Permalink | Reply
    Tags: Boknis Eck Observatory disappears., Smithsonian.com, The observatory cost around 300000. euros ($331425.) but “the data that we collect is downright priceless.   

    From smithsonian.com: “A Huge Underwater Observatory Has Vanished Without a Trace” 

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    From smithsonian.com

    September 6, 2019
    Brigit Katz

    The instrument, located off Germany’s Baltic coast, cost more than $330,000. But its data was ‘priceless,’ one expert said.

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    The frame of the underwater observatory responsible for the power supply during deployment. (Research Dive Center of the CAU)

    Since 2016, a hulking underwater observatory known as “Boknis Eck” has been transmitting data on the ecosystem of the Baltic Sea. But on the evening of August 21, the transmissions suddenly stopped. Divers were dispatched last week to the observatory’s location in Eckernförde Bay, north of the German city of Kiel, to investigate. And when they got there, they were shocked to find that the Boknis Eck had vanished.

    “The devices were gone,” says Hermann Bange of the GEOMAR Helmholtz Center for Ocean Research Kiel, which installed the observatory in conjunction with the Helmholtz Center Geesthacht. “[T]he divers could not find them anymore.”

    All that remained in the Boknis Eck’s place was a frayed cable, which once connected the observatory to the coast, according to the BBC. The Boknis Eck consists of two large frames, one weighing nearly 1,150 pounds and the other 485 pounds, making it unlikely that it was dragged away by a storm, tide or large animal. Humans are a more probable culprit, though the observatory was located in a restricted area, off-limits even to local fishing boats.

    At this point, as Gizmodo’s George Dvorsky points out, it isn’t clear what value looters may have seen in the Boknis Eck. But thieves have been known to scour the bottom of the sea for scrap metal, typically targeting shipwrecks. Earlier this summer, for instance, two WWII-era ships disappeared off the coast of Malaysia; they had contained the remains of 79 crewmen, which also vanished. According to Live Science’s Brandon Specktor, looters typically blow the vessels apart with explosives, then use cranes to pull up any valuable metals.

    Whatever happened to the Boknis Eck, its loss is being keenly felt by researchers. The observatory cost around 300,000 euros ($331,425), but “the data that we collect is downright priceless,” Bange says. The observatory was equipped with various instruments that measure conditions in the southwestern Baltic, like flow velocities and methane concentrations on the seabed. By tracking this data, experts could be alerted to any issues and possibly take countermeasures. So they are anxious to get the Boknis Eck back up and running.

    Police in the town of Eckernförde are on the case, but researchers hope that announcing the loss of the observatory might lead to new clues. “Maybe someone saw something on the morning of 21 August,” Bange says. “Or someone finds parts of the frames somewhere on the beach.”

    See the full article here .

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    Please help promote STEM in your local schools.

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  • richardmitnick 9:16 am on August 3, 2019 Permalink | Reply
    Tags: "Nevada Has a Massive New Dark Sky Sanctuary", , , , , , Nevada's Massacre Ridge, Smithsonian.com   

    From smithsonian.com: “Nevada Has a Massive New Dark Sky Sanctuary” 

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    From smithsonian.com

    The night skies at 100,000-acre Massacre Ridge are some of the starriest in the world.

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    (Richie Bedarski/Friends of Nevada Wilderness )

    August 2, 2019
    Jason Daley

    The view of the night sky from the Massacre Rim Wilderness Study Area is spectacular, but chances are very few people will ever make it to the 100,000-acre plot in Washoe County, Nevada, near the California and Oregon borders, to see it. The area has no hotels, electricity and requires visitors to bring everything they will need with them down long, rugged gravel roads, which boasts rattlesnakes, scorpions and almost no cell service. And that’s just fine. Massacre Rim was recently designated a Dark Sky Sanctuary, and the goal is keep it as dark and undisturbed as possible.

    A Dark Sky Sanctuary is a designation given to an area by the International Dark Sky Association, a group that works to preserve views of the night sky and fight light pollution. The group has several designations for Dark Sky Places, including International Dark Sky Parks, which are existing parks that implement outdoor lighting that preserves the night sky. The Grand Canyon, for instance, just got certified as one. Then there’s Dark Sky Reserves, dark parks or plots of land where nearby landowners and cities cooperate to preserve its dark character. But the darkest of dark places are Dark Sky Sanctuaries, remote areas where a lack of development and human presence have preserved the view of the same starry skies that humans hundreds of years ago would have looked at.

    Massacre Rim easily meets that criteria. According to the Dark Sky Association, the Rim is 150 miles from Reno, Nevada, and 163 miles from Redding, California, the closest major towns. With just four small ranching communities and a population of 800 in the vicinity, humans have very little impact on the night sky in the area, making for a stunning spectacle.

    Despite the fact that Massacre Rim is naturally dark, it did take some effort to earn the title. The designation was spearheaded by the conservation group Friends of Nevada Wilderness, reports Benjamin Spillman at the Reno Gazette. To qualify, last year the group traveled throughout the park via four-wheel drive and on foot, using light measuring instruments and quantifying the night sky using the Bortle Scale, a measure of star visibility and natural light. Those measurements found that the area was close to the top of the chart in star brightness; the starlight was so bright, in fact, it cast shadows.

    The scores were high enough to qualify the area for sanctuary status, which was granted in March. “This designation literally puts Washoe County on the Dark Sky map,” Shaaron Netherton, executive director of Friends of Nevada Wilderness, tells Spillman.

    “While all of the wilderness areas and wilderness study areas in Nevada are special remote places, the Massacre Rim WSA stands out because it is so far from any major populated areas, making light pollution there next to immeasurable,” Netherton says in a press release. “People lucky enough to venture there on a clear moonless night will not only see the enormity of the Milky Way, but will also be awestruck to view our neighboring galaxy, Andromeda, with the naked eye.”

    The designation comes with no legal obligations for the BLM and no requirements from people living nearby to keep the night sky dim.

    Noah Glick of NPR recently visited the new sanctuary. In general, he reports, locals are happy to preserve the skies, one of the things that makes their area special. “It’s something that’s always there and we’ve always taken for granted,” Janet Irene, owner of the Country Hearth restaurant in nearby Cedarville, tells him. “It’s so exciting to know that there’s something else up there, other than what we see every day here. And you can actually see some small part of it. It’s an insight into what might be.”

    Massacre Rim is just one of ten Dark Sky Sanctuaries in the world. It’s the largest of the four designated in the United States, which include New Mexico’s Cosmic Campground, Rainbow Bridge National Monument in Utah and the Devil’s River State Natural Area-Del Norte Unit in southwest Texas.

    Combating light pollution is good for night skies, saves on energy costs and protects bird and bat species that can be disoriented by excess outdoor light. But preserving some slice of the night sky is getting harder and harder. Today, according to Nadia Drake at National Geographic, an estimated 83 percent of people on Earth live with some degree of light pollution, and 99 percent of the United States and Europe are light polluted.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Smithsonian magazine and Smithsonian.com place a Smithsonian lens on the world, looking at the topics and subject matters researched, studied and exhibited by the Smithsonian Institution — science, history, art, popular culture and innovation — and chronicling them every day for our diverse readership.

     
  • richardmitnick 8:53 am on August 3, 2019 Permalink | Reply
    Tags: "New 3-D Map Shows Milky Way’s Big Twist", , , , , Smithsonian.com   

    From smithsonian.com: “New 3-D Map Shows Milky Way’s Big Twist” 

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    From smithsonian.com

    August 2, 2019

    1

    By mapping the distance of Cepheid stars, researchers reveal that our galaxy is warped.

    Milky Way Credits: NASA/JPL-Caltech /ESO R. Hurt. The bar is visible in this image

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    (J. Skowron / OGLE / Astronomical Observatory, University of Warsaw)


    1.3 meter OGLE Warsaw Telescope at the Las Campanas Observatory in Chile, over 2,500 m (8,200 ft) high,

    Most textbooks teach that our galaxy, the Milky Way, resembles a flat spiral, with several prominent arms spinning out from the center. But a new, detailed 3-D map of the galaxy puts a twist in that image, literally. It turns out that the galaxy is not a flat pancake but warped with the edges curling above and below the galactic plane.

    Getting an actual look at our own galaxy is basically impossible. So far, our most distant space probes have barely left our own solar system and will likely never leave the galaxy to capture an image from a distance. So astronomers have to rely on modeling to figure things out using the telescopes and instruments we have. That’s difficult because Earth is parked in a small spiral arm about 26,000 from the galactic center, making it hard to take in the big picture.

    Elizabeth Gibney at Nature reports that prior to this study, the best maps of the Milky Way, which is about 120,000 light years in diameter, used indirect measurements, like counting stars and extrapolating information from other nearby spiral galaxies that we can see. But for this study, researchers from the University of Warsaw used the Optical Gravitational Lensing Experiment telescope at Las Campanas Observatory in Chile to analyze the Cepheids, a group of stars that brighten and dim on a predictable cycle, directly measuring their distances.

    Over the course of six years, the team catalogued 2,341 Cepheids stretching across the galaxy, taking 206,726 images of the stars. Observing stars from Earth, it’s sometimes hard to know how bright they really are. A super-bright star that is very far away may appear dim. But researchers know that the slower a Cepheid star pulses, the brighter it really is, which allows them to calculate its true, or intrinsic, brightness. By comparing the brightness level of the star with its apparent brightness from Earth, the researchers were able to determine the distance and three-dimensional position of each Cepheid with more than 95 percent accuracy. Using these data points, they plotted the positon of the Cepheids throughout the galaxy, creating a structural map. The study appears in the journal Science.

    Researchers using other techniques have hypothesized that the Milky Way is warped and that the galaxy actually flares at the edges. Close to the galactic center, it’s about 500 light years wide. At the edges, it’s about 3,000 light years thick. This new visualization confirms that warp and flare and shows that they’re pretty significant.

    “If we could see our galaxy from the side, we would clearly see its warp,” study leader Dorota Skowron tells George Dvorsky at Gizmodo. “Stars that are 60,000 light-years away from the Milky Way’s center are as far as 5,000 light-years above or below the Galactic plane. This is a big percentage.”

    So why is our galaxy kind of twisted? Nadia Drake at National Geographic reports that warped spiral galaxies are not unusual and astronomers have catalogued many, including the Milky Way’s twin sister galaxy Andromeda. Nicola Davis at The Guardian reports that as many as half the galaxies in the universe have some degree of warping, but the Milky Way’s twists are larger than average.

    It’s not completely clear what curled our edges, but researchers suspect it has to do with interactions between the galaxies in the local group, several dozen galaxies and dwarf galaxies clustered within 10 million light-years of the Milky Way.

    Local Group. Andrew Z. Colvin 3 March 2011

    “We think the warp may have been caused by interactions with satellite galaxies,” Skowron tells Drake. “Other ideas point to interactions with intergalactic gas or dark matter.”

    The new data may also provide some insight into how the galaxy evolved. The researchers identified three patches of Cepheids that are only 20 million to 260 million years old, mere babies compared to the oldest stars in the galaxy, which are 10 to 13 billion years old. The Guardian’s Davis reports that the youngest stars are closer to the galactic center while the older ones are farther out in the spiral arms. It’s possible that interaction with a passing dwarf galaxy could have caused them to pop into existence. Computer simulations show that to create the pattern they are found in, some sort of star forming events had to occur 64 million, 113 million and 175 million years ago.

    Xiaodian Chen from the National Astronomical Observatories at the Chinese Academy of Sciences was part of a similar study published in February[phys.org] that also used a group of Cepheids to map the Milky Way’s 3-D structure. He believes this map is solid. “They essentially confirmed our earlier conclusions regarding the 3-D shape of the Milky Way’s disk, including its flaring in the outer regions,” Chen says. “A good thing about their confirmation of our work is that they used a different data set, covering 2,431 Cepheids compared to [our] 2,330, observed with a different telescope and through different filters. Yet they found pretty much the same result, which is comforting!”

    While this new map is the most accurate in terms of revealing the galaxy’s overall structure, it’s by no means the most detailed look at our galaxy. Last year, the European Space Agency’s Gaia star mapper released the position and brightness of the 1.7 billion stars in our immediate neighborhood in the Milky Way and detailed data on 2 million of those stars.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Smithsonian magazine and Smithsonian.com place a Smithsonian lens on the world, looking at the topics and subject matters researched, studied and exhibited by the Smithsonian Institution — science, history, art, popular culture and innovation — and chronicling them every day for our diverse readership.

     
  • richardmitnick 7:51 am on July 25, 2019 Permalink | Reply
    Tags: "Why Archaeologists and Volcanologists Are Clashing Over Excavations at Pompeii", , , Smithsonian.com,   

    From smithsonian.com: “Why Archaeologists and Volcanologists Are Clashing Over Excavations at Pompeii” 

    smithsonian
    From smithsonian.com

    July 24, 2019
    Meilan Solly

    Volcanologist Roberto Scandone argues that enthusiasm for archaeology has yielded an “act of vandalism to volcanology”.

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    Volcanic deposits found at Pompeii could yield insights on Vesuvius’ future (Morn the Dorn via Wikimedia Commons under CC BY-SA 3.0)

    Since its launch in 2012, the Great Pompeii Project has unearthed finds including mythological frescoes, a “fast food” counter, a preserved horse still in its harness, and a charcoal inscription suggesting Mount Vesuvius erupted in October of 79 A.D.—two months later than has long been believed.

    These discoveries have helped archaeologists paint a clearer portrait of life in the ancient Roman city, but as a team of volcanologists argues in the journal Nature, ongoing excavations come at a high cost: namely, the destruction of volcanic deposits that could yield insights on Vesuvius’ future.

    “[Archaeologists] seem not to realize that the enthusiasm for archaeology is committing an act of vandalism to volcanology,” Roberto Scandone, a volcanologist at Roma Tre University and co-author of the open letter, tells the Guardian’s Hannah Devlin. “Leaving some of the deposits in place is valuable not only for scientists but also for visitors, who will be able to see … first hand how the volcano destroyed the town.”

    According to Newsweek’s Hannah Osborne, Vesuvius is one of the world’s most dangerous volcanoes. Some three million individuals, 600,000 of whom reside in a so-called “red zone,” live in Vesuvius’ shadow, and over the past 2,000 years, the volcano has erupted between 40 to 50 times.

    Still, Christopher Kilburn, a volcanologist at University College London and co-author of the letter, says, researchers aren’t wholly concerned about an imminent eruption—it’s been 75 years since the peak’s last spurt of activity, suggesting Vesuvius is currently dormant. Instead, volcanologists hope to maintain their chances of studying pyroclastic flows, or clouds of gas and magma, and volcanic processes evident in the nearly 2,000-year-old deposits. Per the Nature commentary, similar investigations conducted during the 1980s “revolutionized archaeological reconstructions” of the disaster, pinpointing pyroclastic flows, rather than a rainstorm of pumice, as the main culprit in Pompeii residents’ demise.

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    Vesuvius last erupted in 1944 (Public domain)

    As Kilburn explains to Devlin, “Today we hope to use the archaeology to understand the details of how real pyroclastic flows sweep around real buildings, in order to improve methods of protecting future populations not only on Vesuvius but at similar volcanoes around the world.”

    In a statement provided to Newsweek, Massimo Osanna, general director of the Archaeological Park of Pompeii, notes that an agreement allowing volcanologists to study the area already exists. He adds, “All the excavation activities … were supervised by the volcanologists [from the] University of Naples Federico II, who were able to record the stratigraphy, take samples and construct a damage mapping.”

    Speaking with Osborne, Scandone acknowledges the veracity of Osanna’s words but emphasizes the fact that just one volcanologist and his collaborator have been granted access to the site to date. Meanwhile, the deposits are actively being removed, preventing any possibility of future study.

    “The archaeologists do not see a problem at all,” Scandone says. “Tension [between volcanologists and archaeologists] is avoided because archaeologists simply ignore the question and believe that the site is their property. Two volcanologists have been permitted to see some of the new sections cut through the deposits, but they have no say in whether the sections can be preserved. Until now, this means that no deposits have been preserved in place.”

    According to the Nature letter, volcanologists have asked Italy’s minister for culture to leave strategic portions of Vesuvius’ volcanic deposits untouched. This move, the authors argue, would help experts transform Pompeii and its neighboring settlements into a “natural super-museum for generations to come,” but as Scandone tells Newsweek, archaeologists have yet to comply with the request.

    “There’s a sense of frustration that volcanology is not being taken terribly seriously,” Kilburn explains to the Guardian’s Devlin. “You go to Pompeii and there’s virtually no mention of the volcano at all.”

    Gary Devore, an archaeologist who has previously worked in Pompeii, tells Devlin that researchers are doing their best to “walk that tightrope between slow, meticulous, careful excavation of new rooms … and conserving what they expose as they work.”

    He concludes, “I hope both parties [can] cooperate and respect the value of both side’s expertise. Pompeii is big enough.”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

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    Smithsonian magazine and Smithsonian.com place a Smithsonian lens on the world, looking at the topics and subject matters researched, studied and exhibited by the Smithsonian Institution — science, history, art, popular culture and innovation — and chronicling them every day for our diverse readership.

     
  • richardmitnick 7:30 am on July 25, 2019 Permalink | Reply
    Tags: "Amazing Photos Reveal the Hidden Light of Undersea Life", , Smithsonian.com   

    From smithsonian.com: “Amazing Photos Reveal the Hidden Light of Undersea Life” 

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    From smithsonian.com

    July 24, 2019
    Louise Murray

    Photographer Louise Murray dips into the dark ocean to capture the spectacle of marine fluorescence.

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    Marine species with fluorescent proteins absorb, transform and reemit light, generating a spectacular display of color in the process. (Louise Murray)

    As I descend into dark waters, my blue flashlights reveal a spectacular display of fluorescent colors shining out from some of the corals and marine creatures below. Normally hard to detect with the naked eye, this secret, colorful light show gleams as brightly as an ’80s disco within the beam of my lights.

    Fluorescence on the reef occurs as shorter wavelength blue light is absorbed by special proteins in tissues and is reemitted as longer wavelength greens, reds, oranges and yellows. While the ocean naturally filters light, leaving the underwater world cast predominantly in blue below 15 meters or so, the addition of concentrated blue light from the flashlights and flashguns attached to my camera rig stimulates the strongest response from the fluorescing proteins. Yellow filters on my lenses and dive mask block the stimulating blue light, enabling me to see and capture the full extent of the psychedelic spectacle.

    I’ve been photographing marine fluorescence for over 25 years, capturing it from the Red Sea to the Philippines. I always work at night, when fluorescence is most pronounced against the dark background.

    Marine fluorescence was once dismissed as a phenomenon with no biological function, but scientists around the world are gradually exposing its complicated roles. Far from biologically irrelevant, the proteins are perhaps critical to the health of the reef ecosystem and its ability to respond to stress.

    Photo or fluorescent proteins responsible for fluorescence, also commonly known as pigments, are versatile molecules. In the shallows, where the sun’s rays are intense, the proteins act as a type of sunblock for a coral reef, reducing light stress.

    In deeper, darker waters, these proteins in some types of corals serve to enhance the light instead. All corals live in symbiosis with algae that provide energy to their host through photosynthesis. The proteins help harness and funnel available light, ensuring that even algae deep within a coral’s cells are able to access it.

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    Most of the 83 cryptic species that marine biologist Maarten De Brauwer and his team documented fluorescing are predators, including the tassled scorpionfish, which hunts smaller fish and crustaceans. This particular one was found in Egypt’s Red Sea. (Louise Murray)

    The amount of fluorescent protein a coral produces is determined by its genetics and how strongly the genes are expressed. “There is a great deal of variation in pigment production between individuals of the same species,” explains Jörg Wiedenmann, head of the Coral Reef Laboratory at the University of Southampton in the United Kingdom. “One might fluoresce strongly while the other produces little or no color.” A coral with dramatic biofluorescence may grow slower than its less colorful neighbor under normal conditions, as it spends more of its energy producing fluorescent proteins, but it may have an advantage when taxed by sunlight.

    Marine fluorescence exists in a variety of marine organisms, in temperate and tropical waters. If the roles of the fluorescent molecules are now relatively well understood in corals, the same cannot be said of their purpose in fish. “But it is clear that fluorescence plays an important role in the lives of some fish,” says Nico Michiels, an ecologist at the University of Tübingen in Germany, with the caveat that data is still limited and preliminary. Biologists have discovered that some fish have yellow filters in their eyes, which seems to support the theory that biofluorescence is much more than a pretty byproduct.

    Michiels’s team surveyed hundreds of fish species for fluorescence and found distinct patterns. Smaller species are more likely to fluoresce than larger ones. There is also a strong correlation between a highly camouflaged lifestyle and bright fluorescence. Ambush predators, like stonefish and scorpionfish, are good examples: The broken patterns of fluorescence on these fishes may help them blend into a fluorescing reef background. In some species with distinct differences in appearance between males and females, fluorescence also appears to play a role in sexual attraction.

    Small fish that live in schools may also use red fluorescence in their eye region for short-range communication. Red light will not travel far underwater, so fish like the redeye goby may communicate within a swarm without attracting the attention of predators. The hairy frogfish, part of the anglerfish family, has fluorescent proteins in its lure, which may help attract unwary prey. And scientists suspect that some fish emit fluorescence so that their light reflects off their prey’s eyes, making the potential meal easier to locate.

    Highly camouflaged species are often classed as data deficient for extinction risk because they are so hard to find. But Belgian marine biologist Maarten De Brauwer of the University of Leeds in the United Kingdom surveyed hundreds of fish off Indonesia, Christmas Island, and the Cocos Islands, and found that 87 percent of the species considered cryptic use fluorescence. Inspired by the work of coral scientists who have used blue lights to spot new, very small coral colonies, he looked at whether blue lights could help researchers locate and count hard-to-find species like the tiny pygmy seahorse. “We were able to find double the number of seahorses with blue lights than under normal survey conditions,” he says. “Since biofluorescence is ubiquitous in cryptic species, blue light looks like a very useful tool to survey animals that would otherwise be overlooked.”

    There remains much to discover about fluorescence in marine life, but equip yourself with a blue light and your own yellow filters and you may see it for yourself.

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    The tiny redeye goby is found in small groups swimming around Acropora coral and feeding on zooplankton. The fish has brightly fluorescing eyes, which may allow it to communicate covertly with other members of the group. This particular goby was swimming in the Red Sea. (Louise Murray)

    See the full article for many more incredible images.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Smithsonian magazine and Smithsonian.com place a Smithsonian lens on the world, looking at the topics and subject matters researched, studied and exhibited by the Smithsonian Institution — science, history, art, popular culture and innovation — and chronicling them every day for our diverse readership.

     
  • richardmitnick 12:49 pm on July 9, 2019 Permalink | Reply
    Tags: "Rare Lava Lake Found on Top of Sub-Antarctic Volcano" on the summit of Mount Michael on Saunders Island, , , , Smithsonian.com,   

    From smithsonian com: “Rare Lava Lake Found on Top of Sub-Antarctic Volcano” 

    smithsonian
    From smithsonian.com

    Satellite data located the persistent pool of liquid rock on top of Mt. Michael on Saunders Island, part of the South Sandwich Islands.

    July 8, 2019
    Jason Daley

    Hollywood would have you believe that at the peak of most volcanoes is a roiling, red-hot lake of lava, perfect for human sacrifices or killing James Bond. Persistent lava lakes are actually quite rare; of Earth’s roughly 1,500 volcanoes, only seven are known to have lava lakes. So, the discovery of an eighth lava-topped volcano in the sub-Antarctic Sandwich Islands is a big deal, according to a new study in the Journal of Volcanology and Geothermal Research.

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    (British Antarctic Survey)

    The new lava lake is found on the summit of Mount Michael on Saunders Island, which is part of the British Overseas Territory of South Georgia and the South Sandwich Islands. According to a press release from the British Antarctic Survey, the hot spot was originally hinted at in 2001 when low-resolution satellite data showed a geothermal anomaly at the top of the peak.

    Geologists used higher resolution satellite images of the mountain taken between 2003 and 2018 and cross-referenced that information with additional datasets going back 30 years. Using advanced image processing techniques, they were able to determine that a lake of fire roughly 300 to 700 feet wide was present throughout the time period. They estimated that the lava lake is smoldering between 1,800 and 2,300 Fahrenheit.

    So why didn’t researchers just climb the mountain and peer over the edge? Danielle Gray from University College London, first author of the study, explains that traveling to Saunders Island is extremely difficult and getting to the top is likely impossible except to elite mountaineers.

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    Aerial photograph of Mount Michael. Credit: Pete Bucktrout (British Antarctic Survey)

    “It has been visited at the bottom very rarely, and no one has ever got to the summit,” study co-author Alex Burton-Johnson of the British Antarctic Survey tells Tom Metcalfe at LiveScience.

    The next step in investigating the lava lake is to send a drone or aircraft over the mountain. But even that will take some complicated logistics and lots of money. “The problem is that the South Sandwich Islands are so incredibly remote, there is very little ship traffic that goes past there,” says Burton-Johnson. “So there are not a huge amount of opportunities for research vessels in that area.”

    The discovery of the new lake will help researchers understand how to monitor volcanoes from space and teach them more about the rare, persistent lava pools, which also occur on the Nyiragongo volcano in the Democratic Republic of Congo; the Erta Ale volcano in Ethiopia; Mount Erebus in Antarctica; Kilauea on the island of Hawaii, Mount Yasur and Ambrym in Vanuatu; and Masaya in Nicaragua.

    Why do these volcanoes maintain liquid lava lakes while the molten rock congeals and plugs up most other volcanoes? Burton-Johnson tells Metcalfe that in most cases the steam and superheated gases that power volcanic eruptions isn’t enough to keep rock molten at the surface. But in a few special cases, the gases remain at high enough temperatures to keep a bright orange cauldron of lava bubbling at the summit.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Smithsonian magazine and Smithsonian.com place a Smithsonian lens on the world, looking at the topics and subject matters researched, studied and exhibited by the Smithsonian Institution — science, history, art, popular culture and innovation — and chronicling them every day for our diverse readership.

     
  • richardmitnick 8:12 am on May 1, 2019 Permalink | Reply
    Tags: "One-Third of Exoplanets Could Be Water Worlds With Oceans Hundreds of Miles Deep", , , , , Smithsonian.com   

    From smithsonian.com: “One-Third of Exoplanets Could Be Water Worlds With Oceans Hundreds of Miles Deep” 

    smithsonian
    From smithsonian.com

    4.30.19
    Jason Daley

    2
    NASA

    Scientists often search for water in space because on Earth, anywhere there is water, there is life.

    Rovers on Mars are looking for present-day water or ice as well as signs of ancient rivers and oceans. They’ve scoured the moon looking for signs of ice deep in its craters and even sent a probe to look for ice on a comet. But new research suggests finding cosmic H2O may not be all that difficult outside our own solar system. Simulations based on exoplanet data suggest water worlds covered with deep oceans may actually be rather common throughout our galaxy, according to a new study published this week in PNAS.

    Since 1992, astronomers have catalogued about 4,000 exoplanets orbiting around distant stars. It turns out that most of those planets fall into two size categories: smaller planets with a radius about 1.5 times that of Earth and a mass about five times our planet and larger planets with a radius 2.5 times that of our planet and ten times the mass. Jamie Carter at Forbes reports that researchers believe the planets with smaller radii are rocky worlds. They interpreted the size and mass of the larger planets as a class of planets called gas dwarfs, which have a rocky core surrounded by a halo of gas.

    Using new data about the radii and mass of exoplanets collected by the Gaia space satellite, Harvard planetary scientist Li Zeng and his colleagues gather more details about the exoplanets’ internal structures.

    ESA/GAIA satellite

    They found that those big gas dwarfs are better explained as water worlds. But these are not water worlds like Earth, where despite covering 71 percent of the surface, water only accounts for 0.02 percent of Earth’s mass. Instead, these worlds are made of 25 percent and up to 50 percent water, with strange, vast oceans covering them. It’s possible that up to 35 percent of all known exoplanets are these vast ocean-covered orbs, Li noted at a conference last summer.

    “This is water, but not as commonly found here on Earth,” Li says in a press release. “Their surface temperature is expected to be in the 200 to 500 degree Celsius range. Their surface may be shrouded in a water-vapor-dominated atmosphere, with a liquid water layer underneath. Moving deeper, one would expect to find this water transforms into high-pressure ices before… reaching the solid rocky core. The beauty of the model is that it explains just how composition relates to the known facts about these planets.”

    Li explains George Dvorsky at Gizmodo in an email that these planets may or may not have a defined surface. The oceans could be hundreds of miles deep, calling them: “Unfathomable. Bottomless. Very Deep.” By comparison, the deepest known spot in the Earth’s oceans, Challenger Deep in the Mariana Trench, is less than seven miles deep.

    The weight of all that water would create pressures over a million times that found on the surface of Earth, leading to some very strange phenomenon at the bottom, including the formation of “hot, hard” rock-like phases of ice, like Ice VII.

    So if these water worlds are so common, why don’t we have one like them in our solar system? Zeng tells Carter that it’s possible our planetary system may be an oddball because we have massive gas giants like Jupiter and Saturn floating around.

    “The formation of gas giants and the formation of those close-in super-Earths and sub-Neptunes are somewhat mutually exclusive,” he says. “Our solar system had formed the gas giant Jupiter early on, which probably had prevented or interfered with the formation and growth of super-Earths and sub-Neptunes.”

    In other star systems without a Jupiter-sized planet, the formation of rocky “super-Earths” and water worlds is probably pretty common.

    Sean Raymond, an astronomer at the University of Bordeaux who was not involved in the study, tells Dvorsky the study seems spot on, but cautions that we don’t have direct confirmation of all these water worlds. Our current methods of detecting exoplanets are indirect, and we have to infer what we know from their radius, mass, orbiting time and other data.

    “[The study’s] conclusions are statistical, meaning that the authors are not pointing to specific planets and claiming them to be water worlds but rather focusing on the population as a whole,” he says. “Still, it’s a cool paper and a provocative result.”

    As to whether some form of cosmic-aquatic life may be out there, it’s hard to say. But we may get more information soon when the beleaguered James Webb Space Telescope launches in 2021. That next-gen space scope should be capable of directly detecting water on distant exoplanets.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Smithsonian magazine and Smithsonian.com place a Smithsonian lens on the world, looking at the topics and subject matters researched, studied and exhibited by the Smithsonian Institution — science, history, art, popular culture and innovation — and chronicling them every day for our diverse readership.

     
  • richardmitnick 8:59 am on March 14, 2019 Permalink | Reply
    Tags: "Flooding Creates a 10-Mile-Long Lake in Death Valley", , , Smithsonian.com, The rare ephemeral lake was caused when the compacted dry desert soil wasn’t able to absorb the .87 inches of rain that recently fell on the national park.   

    From smithsonian.com: “Flooding Creates a 10-Mile-Long Lake in Death Valley” 

    smithsonian
    From smithsonian.com

    March 13, 2019
    Jason Daley

    The rare ephemeral lake was caused when the compacted, dry desert soil wasn’t able to absorb the .87 inches of rain that recently fell on the national park.

    1
    (Elliot McGucken, http://www.mcgucken.com)

    Most of the time, visitors to Death Valley National Park in southern California don’t expect to see much water. The area is the hottest and driest spot in North America. So it was surprising when, after a massive storm last week, a winding 10-mile-long lake appeared in the park.

    The shallow body of water was discovered by photographer Elliott McGucken on March 7, reports Amy Graff at SFGate.com. After the storm moved through the area, McGucken was planning to visit Badwater Basin to take some photos, hoping that an ephemeral lake had formed in the area. But he couldn’t reach the spot because the other, larger lake along Salt Creek blocked the way.

    It actually turned out to be even better than Badwater Basin. McGucken was able to shoot some once-in-a-lifetime images of the flooding with the surrounding Panamint Mountains reflected in the water. “Nature presents this ephemeral beauty, and I think a lot of what photography is about is searching for it and then capturing it,” he tells Graff.

    While it’s difficult to pin down just how large the lake is, the National Park Service estimates that it stretches about 10 miles. “I believe we would need aerial photos to accurately determine the size. From the road, it looks like it stretched from approximately Harmony Borax Works to Salt Creek right after the rain, which is a little less than 10 road miles,” the park said in a statement emailed to McGucken. “But, the road does curve a bit, so it’s not an entirely accurate guess.”

    According to Pam Wright at Weather.com, the flooding occurred because on March 5 and 6, the Park received .87 inches of rain, almost three times the average for March. The deluge represents about one-third of Death Valley’s total annual precipitation.

    The parched, compacted soil of the desert can be like concrete, and is unable to suck up such a large amount of rain quickly. “Because water is not readily absorbed in the desert environment, even moderate rainfall can cause flooding in Death Valley,” Weather.com meteorologist Chris Dolce explains. “Flash flooding can happen even where it is not raining. Normally dry creeks or arroyos can become flooded due to rainfall upstream.”

    Park officials tell Graff the lake is still present, though it is gradually getting smaller.

    2
    (Elliot McGucken, http://www.mcgucken.com)

    Sadly, the rains have come too late to power a superbloom in Death Valley, reports the NPS. Superblooms occur when the desert gets above average rainfall at the right time in the winter months, leading to an irruption of desert flowers. Currently, a superbloom, the second in two years, is taking place in Anza-Borrego Desert State Park, the state’s largest, which received the right amount of rain early on. Fields of orange poppies, purple sand verbena, white and yellow primroses and other desert wildflowers are blossoming in unison.

    Death Valley experienced a major superbloom in 2005 and it’s latest superbloom was in 2016. Those flowers, however, came with a price. In October 2015, the park experienced the largest flood event in the Valley’s recorded history when between 1 to 2 inches of rain fell over the park. At that time, Badwater Basin, normally a dry lake bed, filled with water. The road to the Scotty’s Castle area of the park was closed, and it is still not expected to reopen until 2020.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Smithsonian magazine and Smithsonian.com place a Smithsonian lens on the world, looking at the topics and subject matters researched, studied and exhibited by the Smithsonian Institution — science, history, art, popular culture and innovation — and chronicling them every day for our diverse readership.

     
  • richardmitnick 11:18 am on March 13, 2019 Permalink | Reply
    Tags: "Streams of Stars Snaking Through the Galaxy Could Help Shine a Light on Dark Matter", Adrian Price-Whelan calls GD-1 "the Goldilocks stream" because it's in just the right place., , , At about 33000 light-years (10 kiloparsecs) GD-1 is the longest stellar stream in the galactic halo, , , Dark matter makes up the bulk of the mass in the universe but it has never been directly observed, , , , scores of dark matter seeds are scattered through galaxies like the Milky Way, Smithsonian.com, The stellar stream known as GD-1 is a thin flow of material tucked inside the Galactic halo   

    From smithsonian.com: “Streams of Stars Snaking Through the Galaxy Could Help Shine a Light on Dark Matter” 

    smithsonian
    From smithsonian.com

    March 12, 2019
    Nola Taylor Redd

    When the Milky Way consumes another galaxy, tendrils of stellar streams survive the merger, containing clues about the universe’s mysterious unseen matter.

    1
    An ultraviolet image of the Andromeda galaxy, the closest major galaxy to the Milky Way, taken by NASA’s Galaxy Evolution Explorer space telescope. Like our own galaxy, Andromeda is a spiral galaxy with a flat rotating disk of stars and gas and a concentrated bulge of stars at the center. (NASA/JPL-Caltech)

    When a small galaxy strays too close to the Milky Way, the gravity from our larger galaxy reels it in. Gas and stars are ripped from the passing galaxy as it falls inward toward its doom, creating streams of material that stretch between the galactic pair. These streams continue to tear away stars until the infalling object has been completely consumed. After the merger is over, some of the only remaining signs of the devoured object are the stellar streams snaking through the Milky Way, a small sample of stars from a galaxy long gone.

    In addition to being a record of the past, one of these streams may provide the first direct evidence for small scale clusters of dark matter—the elusive material that is believed to account for 85 percent of all matter in the universe. A recent analysis of a trail of stars reveals that it interacted with a dense object in the last few hundred million years. After ruling out the most likely suspects, the researchers determined that the relatively recently made gap in the stream may have been caused by a small clump of dark matter. If confirmed, the eddies of this stellar stream could help scientists sort through the competing theories about dark matter and perhaps even close in on the characteristics of the mysterious material.

    The stellar stream known as GD-1 is a thin flow of material tucked inside the Galactic halo, the loose collection of stars and gases surrounding the disk of the Milky Way. Using data released last April from the European Space Agency’s Gaia space telescope, which is in the process of assembling the most detailed map of the Milky Way’s stars ever made, astronomers were able to use precise positional data to reconstruct the movement of the stars in GD-1.

    ESA/GAIA satellite

    Torn from a cloud of material, the stream is the last remnant of an object that was likely consumed by our galaxy in the last 300 million years—an eyeblink on astronomical timescales.

    Gaia found two small breaks in the stream, the first unambiguous observation of gaps in a stellar stream, as well as a dense collection of stars called a spur. Together, these features suggest that a small but massive object shook up the material of the stream.

    “I think this is the first direct dynamical evidence for the small-scale [structure] of dark matter,” says Adrian Price-Whelan, an astronomer at the Flatiron Institute in New York. Working with Ana Bonaca of the Harvard-Smithsonian Center for Astrophysics, Price-Whelan investigated the newfound structures in GD-1 to determine their source and presented the results earlier this year at the winter meeting of the American Astronomical Society.

    At about 33,000 light-years (10 kiloparsecs), GD-1 is the longest stellar stream in the galactic halo. While Price-Whelan and his colleagues were able to use models to show that one of the gaps formed during the generation of the stream, the other gap remained a mystery. However, along with the puzzle, Gaia also revealed a solution: the spur.

    When an object travels past or through a stellar stream, it disrupts the stars. Price-Whelan compares the disruption to a strong jet of air blowing across a stream of water. The water—or stars—plume outward along the path of the disruptor, creating a gap. Some move so fast that they escape the stream and go flying off into space, lost forever. Others are pulled back into the stream to form eddy-like features astronomers call spurs. After a few hundred million years, most spurs merge back into the stream, and only the gap remains, though some can be longer-lived.

    When it comes to spotting structures in stellar streams, Price-Whelan calls GD-1 “the Goldilocks stream” because it’s in just the right place. GD-1 is within the stars of the Milky Way, but moving in the opposite direction, making it easier for astronomers to pick out the stars in the stream from the surrounding objects. “At any given location, it’s moving differently from the way most of the other stars in that part of the sky are moving,” Price-Whelan says.

    The researchers modeled what type of objects could be responsible for the relatively newborn spur spotted in GD-1. They determined that the responsible object had to weigh in with a mass somewhere between 1 million and 100 million times the mass of the sun. Stretching only about 65 light-years (20 pc) in length, the object would have been incredibly dense. The interaction between the stream and the dense object would have likely happened within the last few hundred million years out of the 13.8-billion-year lifetime of the universe.

    Milky Way NASA/JPL-Caltech /ESO R. Hurt

    Dark matter isn’t the only object that could have disrupted the stellar stream. A globular cluster or dwarf galaxy swooping nearby could also have created the gap and spur. Price-Whelan and his colleagues turned their eyes toward all known such objects and calculated their orbits, finding that none came close enough to GD-1 in the last billion years to shake things up. A chance encounter with a primordial black hole could have sent the stream’s stars flying, but it would have been an extremely rare event.

    According to dark matter simulations that allow for small structures, scores of dark matter seeds are scattered through galaxies like the Milky Way. A stream like GD-1 is expected to encounter at least one such seed within the last 8 billion years, making dark matter a far more likely perturber based on encounter rates than any other object.

    Dark matter makes up the bulk of the mass in the universe, but it has never been directly observed. The two leading theories for its existence are the warm dark matter model and the Lambda cold dark matter model (ΛCDM), which is the model preferred by most scientists.

    Lambda-Cold Dark Matter, Accelerated Expansion of the Universe, Big Bang-Inflation (timeline of the universe) Date 2010 Credit: Alex Mittelmann Cold creation

    Under ΛCDM, dark matter forms clumps that can be as large as a galaxy or as small as a soda can. Warm dark matter models suggest that the material has less massive particles and lacks the can-sized structures that the ΛCDM model suggests. Finding evidence for small scale structures of dark matter could help weed out certain models and start to narrow in on some of the characteristics of the tantalizing stuff.

    “Streams might be the only avenue that we could [use to] study the lowest mass end of what dark matter is doing,” Price-Whelan says. “If we want to be able to confirm or reject or rule out different theories of dark matter, we really need to know what’s happening at [the low] end.”

    Gaia’s data helped identify the stars of the spur, but it’s not detailed enough to compare the velocity differences between them and the stars in the stream, which could help confirm that dark matter perturbed the structure. Price-Whelan and his colleagues want to use NASA’s Hubble Space Telescope to further study the movement of the faint stars in GD-1. Although Gaia has opened the door to wide-scale examination of the movement of stars across the Milky Way, Price-Whelan says that it can’t compete with the HST when it comes to very faint stars. “You can drill much deeper when you have a dedicated telescope like Hubble,” he says.

    The differences in how the stars of the stream and spur move could help astronomers determine how much energy the perturbing object carried, as well as allow researchers to calculate its orbit. These pieces of information could be used to track down the disruptive dark matter clump and study its immediate environment.

    In addition to making a more in-depth study of GD-1, astronomers plan to apply the same techniques enabled by Gaia’s data to some of the more than 40 other streams surrounding the Milky Way. Spotting spurs and gaps in other streams and tying them to dark matter could further improve our understanding of how the mysterious substance interacts with the visible galaxy.

    After decades of puzzling over the mystery of dark matter, the gaps and spurs in stellar streams like GD-1 may finally help to reveal the secrets of the substance that makes up most of the universe. “This is one of the most exciting things that has come out of Gaia,” Price-Whelan says.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Smithsonian magazine and Smithsonian.com place a Smithsonian lens on the world, looking at the topics and subject matters researched, studied and exhibited by the Smithsonian Institution — science, history, art, popular culture and innovation — and chronicling them every day for our diverse readership.

     
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