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  • richardmitnick 9:29 pm on May 17, 2021 Permalink | Reply
    Tags: "Could Weirdly Straight Bolts of Lightning Be a Sign of Dark Matter?", "macros", , , Smithsonian.com   

    From smithsonian.com : “Could Weirdly Straight Bolts of Lightning Be a Sign of Dark Matter?” 

    smithsonian

    From smithsonian.com

    May 13, 2021
    Dan Falk

    1
    So far, scientists have only documented jagged lightning bolts. Some physicists believe that the discovery of a completely straight lightning bolt could prove the existence of dark matter. Credit: Fadi Al-Shami / SOPA Images / LightRocket via Getty Images.

    For decades, astronomers and physicists have been flummoxed by the mystery of Dark Matter, spending billions of dollars on sophisticated detectors to search for the elusive particles believed to account for some 85 percent of the matter in the universe. So far, those searches have come up empty. Now a team of scientists has proposed a very different strategy for searching for signs of dark matter, not by means of particle physics laboratories, but by examining the air above us. If we carefully study the flashes seen in ordinary lightning storms, they argue, we just might find evidence of super-dense chunks of dark matter as they zip through our atmosphere. They believe that these speeding chunks of dark matter, known as “macros,” would trigger perfectly straight lightning bolts, which have never been documented.

    The case for dark matter has been building since the 1930s, when astronomers first noticed that galaxies move as though they contain more matter than what we can actually see with our telescopes; as a result, researchers believe there must be a large quantity of unseen matter along with the ordinary, visible stuff.

    _____________________________________________________________________________________

    Dark Matter Background
    Fritz Zwicky discovered Dark Matter in the 1930s when observing the movement of the Coma Cluster., Vera Rubin a Woman in STEM denied the Nobel, some 30 years later, did most of the work on Dark Matter.

    Fritz Zwicky from http:// palomarskies.blogspot.com.


    Coma cluster via NASA/ESA Hubble.


    In modern times, it was astronomer Fritz Zwicky, in the 1930s, who made the first observations of what we now call dark matter. His 1933 observations of the Coma Cluster of galaxies seemed to indicated it has a mass 500 times more than that previously calculated by Edwin Hubble. Furthermore, this extra mass seemed to be completely invisible. Although Zwicky’s observations were initially met with much skepticism, they were later confirmed by other groups of astronomers.
    Thirty years later, astronomer Vera Rubin provided a huge piece of evidence for the existence of dark matter. She discovered that the centers of galaxies rotate at the same speed as their extremities, whereas, of course, they should rotate faster. Think of a vinyl LP on a record deck: its center rotates faster than its edge. That’s what logic dictates we should see in galaxies too. But we do not. The only way to explain this is if the whole galaxy is only the center of some much larger structure, as if it is only the label on the LP so to speak, causing the galaxy to have a consistent rotation speed from center to edge.
    Vera Rubin, following Zwicky, postulated that the missing structure in galaxies is dark matter. Her ideas were met with much resistance from the astronomical community, but her observations have been confirmed and are seen today as pivotal proof of the existence of dark matter.

    Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science).


    Vera Rubin measuring spectra, worked on Dark Matter (Emilio Segre Visual Archives AIP SPL).


    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970. https://home.dtm.ciw.edu.


    _____________________________________________________________________________________

    The leading theory is that dark matter is made up of elementary particles, perhaps created some 14 billion years ago at the time of the Big Bang. These hypothetical objects are called “weakly interacting massive particles,” or WIMPs. Typical WIMP searches employ huge vats of an ultra-dense liquid such as xenon; if a dark matter particle hits the liquid, physicists should be able to see the radiation emitted by atomic nuclei as they recoil from collisions with WIMPs. But numerous such experiments have found nothing so far—leading some scientists to wonder if dark matter may be made of something else altogether. Macros are one of several alternatives to WIMPS that have been put forward. The idea is that dark matter, rather than being composed of elementary particles, is actually made up of macroscopic clumps of matter. These clumps may weigh as much as a few ounces, perhaps the weight of a golf ball. However, because of their extreme density (several hundred pounds per cubic inch), all of that mass would be packed into a space about the size of a bacterium. But, crucially, macros are unlikely to be just sitting around; more likely, they’re whipping through space with speeds of between roughly 150 and 300 miles per second (compared to roughly a half mile per second for a rifle bullet).

    If a macro happened to pass through Earth’s atmosphere, it would release so much energy it would strip the electrons off the atoms that it pushed aside, creating a long, pencil-thin channel of charged particles, known as ions, in the air. Normally, such an ion channel would be invisible—but if there happens to be an electrical storm underway, the channel would offer a conduit for lightning. But unlike ordinary lightning, which is jagged, these macro-induced bolts of lightning would be straight as an arrow, according to physicist Glenn Starkman of Case Western Reserve University (US), and his son Nathaniel Starkman, a physics graduate student at the University of Toronto (CA). Their paper, co-authored with colleagues Harrison Winch and Jagjit Singh Sidhu, examines the mechanism by which macros might trigger lightning, as well as several other novel means for searching for evidence of macros. It was published in April in the journal Physical Review D.

    “Since these macros are traveling so fast, they’re not really affected by wind—so these ion channels are remarkably straight, cutting directly through the earth’s atmosphere,” says the younger Starkman. Lightning normally travels along disjointed, crooked paths as it tries to find the path of least resistance between clouds and the ground. Because of fluctuations in temperature and humidity, that path is typically erratic, producing a characteristic zigag pattern. But once a macro has created a perfectly straight ion channel, the lightning would “snap into place,” resulting in a super-straight bolt. “It’s still bright, it’s still loud—but it’s no longer jagged,” Nathaniel says.

    Because macros carry so much energy in such a compact form, they could pass right through the Earth and emerge intact from the other side. As the authors note in their paper, the straight lightning that they describe could be the result of a macro coming down from space, or coming up from below, having already zipped through our planet.

    To date, nobody has ever seen such a straight bolt of lightning. The closest that’s ever been recorded was a nearly straight lightning bolt seen in Zimbabwe in 2015, but it wasn’t straight enough, the authors say. But the lack of evidence may simply be due to the lack of any coordinated search effort. In their paper, the Starkmans suggest taking advantage of extant networks of cameras that scan the sky for meteors, fireballs and bolides—meteors that break apart and create multiple streaks. However, the software used by those networks of meteor cameras would have to be tweaked; having been designed to look for meteors, they’re programmed to filter out lightning strikes.

    How many instances of straight lightning such a search might turn up depends on many factors, including the mass, size and speed of the macros, and how many of them exist in a given volume of space—all of which are very uncertain figures. As a ballpark estimate, the Starkmans suggest that as many as 50 million macros might be hitting our atmosphere per year—but, unless a macro hits where a lightning storm is underway, we’re unlikely to notice it. “If we’re lucky, we’ll discover that actually there are straight lightning bolts, and we just haven’t been monitoring them,” says Glenn. “One would be interesting; more than one would be nice,” adds Nathaniel.

    The notion of looking for evidence of dark matter in a phenomenon as routine as lightning is “very cool,” says Sean Tulin, a physicist at York University (CA) in Toronto. “It’s definitely an interesting and very creative idea.” The fact that no other dark matter search has yet hit paydirt means physicists ought to be open-minded, he says. “The field of particle physics, and dark matter physics, is at a crossroads—and people are really having a re-think about what other types of particles [beyond WIMPs] it might be.”

    The idea of macros are not new; physicist Ed Witten, well known for his work on string theory, wrote about the possible existence of objects somewhat like macros, but even denser—he called them “quark nuggets”—in a paper [Physical Review D] in the 1980s, and even suggested these exotic objects as a potential dark matter candidate. But whether ultra-dense objects like macros or quark nuggets would be stable over long periods of time remains a point of debate.

    In their paper, the Starkmans also suggest other places where speedy macros might have left their mark—including something you might have in your kitchen. If a macro zipped through a slab of granite sometime in the Earth’s history, they argue, it would have melted a pencil-like line through the rock, which would then have re-solidified; geologists refer to this type of rock, which was molten and then solidified, as obsidian. If a thin slab were cut from a block of granite that had been pierced by a macro, there would be a telltale oval patch of obsidian, perhaps half an inch across, on both sides of the slab. “It turns out when you melt granite and then cool it, it forms obsidian, which looks different from granite,” says Glenn of the dark-colored igneous rock. He’s encouraging people to examine slabs of granite that they might see at home renovation shops, or even in their own kitchens (though once installed as a kitchen countertop, it may be hard to see both sides of the slab). He also hopes to set up a citizen science website to allow people to submit photos of suspicious slabs of granite.

    A third place to look for signs of macros might be on the planet Jupiter, the authors suggest. Jupiter has much bigger electrical storms than Earth, which increases the chances of a macro slicing through such a storm. Such events may produce distinctive radio signals, Glenn says, which could be monitored from a satellite in orbit around the planet.

    All of this may sound somewhat off-the-mainstream—but then again, years of searching by more traditional methods have yet to turn up any concrete signs of dark matter. Of course, it’s possible that an exhaustive study of lightning storms, granite slabs and Jupiter’s atmosphere may similarly fail to produce any hints of dark matter—but even a negative result can be useful in physics, by helping to constrain theoretical models. “Any time you can rule out otherwise-viable hypotheses, no matter how unlikely, that’s a little bit of progress,” says Dan Hooper, a physicist at DOE’s Fermi National Accelerator Laboratory (US) in Illinois. The Starkmans’ paper “is legitimate science. It’s a step toward getting an answer.”

    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.
    The Smithsonian Institution (US) is a trust instrumentality of the United States composed as a group of museums and research centers. It was founded on August 10, 1846, “for the increase and diffusion of knowledge”. The institution is named after its founding donor, British scientist James Smithson. It was originally organized as the “United States National Museum”, but that name ceased to exist as an administrative entity in 1967.

    Termed “the nation’s attic” for its eclectic holdings of 154 million items, the Institution’s 19 museums, 21 libraries, nine research centers, and zoo include historical and architectural landmarks, mostly located in the District of Columbia. Additional facilities are located in Maryland, New York, and Virginia. More than 200 institutions and museums in 45 states, Puerto Rico, and Panama are Smithsonian Affiliates.

    The Institution’s 30 million annual visitors are admitted without charge. Its annual budget is around $1.2 billion, with two-thirds coming from annual federal appropriations. Other funding comes from the Institution’s endowment, private and corporate contributions, membership dues, and earned retail, concession, and licensing revenue. Institution publications include Smithsonian and Air & Space magazines.

    Research centers and programs

    The following is a list of Smithsonian research centers, with their affiliated museum in parentheses:

    Archives of American Art
    California State Railroad Museum
    Carrie Bow Marine Field Station (Natural History Museum)
    Center for Earth and Planetary Studies (Air and Space Museum)
    Center for Folklife and Cultural Heritage
    Marine Station at Fort Pierce (Natural History Museum)
    Smithsonian Migratory Bird Center (National Zoo)
    Museum Conservation Institute
    Smithsonian Asian Pacific American Center
    Smithsonian Astrophysical Observatory and the associated Harvard–Smithsonian Center for Astrophysics
    Smithsonian Conservation Biology Institute (National Zoo)
    Smithsonian Environmental Research Center
    Smithsonian Institution Archives
    Smithsonian Libraries
    Smithsonian Institution Scholarly Press
    Smithsonian Latino Center
    Smithsonian Provenance Research Initiative (SPRI)
    Smithsonian Science Education Center
    Smithsonian Tropical Research Institute (Panamá)
    Woodrow Wilson International Center for Scholars

    Also of note is the Smithsonian Museum Support Center (MSC), located in Silver Hill, Maryland (Suitland), which is the principal off-site conservation and collections facility for multiple Smithsonian museums, primarily the National Museum of Natural History. The MSC was dedicated in May 1983. The MSC covers 4.5 acres (1.8 ha) of land, with over 500,000 square feet (46,000 m^2) of space, making it one of the largest set of structures in the Smithsonian. It has over 12 miles (19 km) of cabinets, and more than 31 million objects.

     
  • richardmitnick 3:53 pm on May 16, 2021 Permalink | Reply
    Tags: "Earth’s Oldest Minerals Date Onset of Plate Tectonics to 3.6 Billion Years Ago", , , , High-aluminum zircons can only be produced in a limited number of ways which allows researchers to use the presence of aluminum to infer what may have been going on., , , Plate tectonics emerged roughly 3.6 billion years ago., Prior research on the 4 billion-year-old Acasta Gneiss in northern Canada also suggests that Earth’s crust was thickening and causing rock to melt deeper within the planet., Reconstructing how the Earth changed from a molten ball of rock and metal to what we have today., Smithsonian.com, The aluminum content of each zircon was also of interest to the research team., The oldest of the zircons in the study which came from the Jack Hills of Western Australia were around 4.3 billion years old., The results from the Acasta Gneiss give scientists more confidence in our interpretation of the Jack Hills zircons., The scientists deciphered a marked increase in aluminum concentrations roughly 3.6 billion years ago., The study uses zircons-the oldest minerals ever found on Earth-to peer back into the planet’s ancient past., These minerals provide the closest thing researchers have to a continuous chemical record of the nascent world., These nearly indestructible minerals formed when the Earth itself was in its infancy-only roughly 200 million years old., This work is part of the museum’s new initiative called Our Unique Planet.   

    From smithsonian.com “Earth’s Oldest Minerals Date Onset of Plate Tectonics to 3.6 Billion Years Ago” 

    smithsonian

    From smithsonian.com

    May 14, 2021

    Media Only
    Ryan Lavery
    (202) 633-0826
    laveryr@si.edu

    Randall Kremer
    (202) 633-0817
    kremerr@si.edu

    Press Office
    Media only
    Phone: (202) 633-2950
    Fax: (202) 786-2982

    Ancient Zircons From the Jack Hills of Western Australia Hone Date of an Event That Was Crucial To Making the Planet Hospitable to Life.

    1
    Credit: Michael Ackerson, Smithsonian.

    Scientists led by Michael Ackerson, a research geologist at the Smithsonian’s National Museum of Natural History, provide new evidence that modern plate tectonics, a defining feature of Earth and its unique ability to support life, emerged roughly 3.6 billion years ago.

    Earth is the only planet known to host complex life and that ability is partly predicated on another feature that makes the planet unique: plate tectonics. No other planetary bodies known to science have Earth’s dynamic crust, which is split into continental plates that move, fracture and collide with each other over eons. Plate tectonics afford a connection between the chemical reactor of Earth’s interior and its surface that has engineered the habitable planet people enjoy today, from the oxygen in the atmosphere to the concentrations of climate-regulating carbon dioxide. But when and how plate tectonics got started has remained mysterious, buried beneath billions of years of geologic time.

    The study, published May 14 in the journal Geochemical Perspective Letters, uses zircons-the oldest minerals ever found on Earth-to peer back into the planet’s ancient past.

    The oldest of the zircons in the study which came from the Jack Hills of Western Australia were around 4.3 billion years old—which means these nearly indestructible minerals formed when the Earth itself was in its infancy-only roughly 200 million years old. Along with other ancient zircons collected from the Jack Hills spanning Earth’s earliest history up to 3 billion years ago, these minerals provide the closest thing researchers have to a continuous chemical record of the nascent world.

    “We are reconstructing how the Earth changed from a molten ball of rock and metal to what we have today,” Ackerson said. “None of the other planets have continents or liquid oceans or life. In a way, we are trying to answer the question of why Earth is unique, and we can answer that to an extent with these zircons.”

    To look billions of years into Earth’s past, Ackerson and the research team collected 15 grapefruit-sized rocks from the Jack Hills and reduced them into their smallest constituent parts—minerals—by grinding them into sand with a machine called a chipmunk. Fortunately, zircons are very dense, which makes them relatively easy to separate from the rest of the sand using a technique similar to gold panning.

    The team tested more than 3,500 zircons, each just a couple of human hairs wide, by blasting them with a laser and then measuring their chemical composition with a mass spectrometer. These tests revealed the age and underlying chemistry of each zircon. Of the thousands tested, about 200 were fit for study due to the ravages of the billions of years these minerals endured since their creation.

    “Unlocking the secrets held within these minerals is no easy task,” Ackerson said. “We analyzed thousands of these crystals to come up with a handful of useful data points, but each sample has the potential to tell us something completely new and reshape how we understand the origins of our planet.”

    A zircon’s age can be determined with a high degree of precision because each one contains uranium. Uranium’s famously radioactive nature and well-quantified rate of decay allow scientists to reverse engineer how long the mineral has existed.

    The aluminum content of each zircon was also of interest to the research team. Tests on modern zircons show that high-aluminum zircons can only be produced in a limited number of ways which allows researchers to use the presence of aluminum to infer what may have been going on, geologically speaking, at the time the zircon formed.

    After analyzing the results of the hundreds of useful zircons from among the thousands tested, Ackerson and his co-authors deciphered a marked increase in aluminum concentrations roughly 3.6 billion years ago.

    “This compositional shift likely marks the onset of modern-style plate tectonics and potentially could signal the emergence of life on Earth,” Ackerson said. “But we will need to do a lot more research to determine this geologic shift’s connections to the origins of life.”

    The line of inference that links high-aluminum zircons to the onset of a dynamic crust with plate tectonics goes like this: one of the few ways for high-aluminum zircons to form is by melting rocks deeper beneath Earth’s surface.

    “It’s really hard to get aluminum into zircons because of their chemical bonds,” Ackerson said. “You need to have pretty extreme geologic conditions.”

    Ackerson reasons that this sign that rocks were being melted deeper beneath Earth’s surface meant the planet’s crust was getting thicker and beginning to cool, and that this thickening of Earth’s crust was a sign that the transition to modern plate tectonics was underway.

    Prior research on the 4 billion-year-old Acasta Gneiss in northern Canada also suggests that Earth’s crust was thickening and causing rock to melt deeper within the planet.

    “The results from the Acasta Gneiss give us more confidence in our interpretation of the Jack Hills zircons,” Ackerson said. “Today these locations are separated by thousands of miles, but they’re telling us a pretty consistent story, which is that around 3.6 billion years ago something globally significant was happening.”

    This work is part of the museum’s new initiative called Our Unique Planet, a public–private partnership, which supports research into some of the most enduring and significant questions about what makes Earth special. Other research will investigate the source of Earth’s liquid oceans and how minerals may have helped spark life.

    Ackerson said he hopes to follow up these results by searching the ancient Jack Hills zircons for traces of life and by looking at other supremely old rock formations to see if they too show signs of Earth’s crust thickening around 3.6 billion years ago.

    Funding and support for this research were provided by the Smithsonian and the National Aeronautics and Space Administration (NASA).

    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.

    The Smithsonian Institution (US) is a trust instrumentality of the United States composed as a group of museums and research centers. It was founded on August 10, 1846, “for the increase and diffusion of knowledge”. The institution is named after its founding donor, British scientist James Smithson. It was originally organized as the “United States National Museum”, but that name ceased to exist as an administrative entity in 1967.

    Termed “the nation’s attic” for its eclectic holdings of 154 million items, the Institution’s 19 museums, 21 libraries, nine research centers, and zoo include historical and architectural landmarks, mostly located in the District of Columbia. Additional facilities are located in Maryland, New York, and Virginia. More than 200 institutions and museums in 45 states, Puerto Rico, and Panama are Smithsonian Affiliates.

    The Institution’s 30 million annual visitors are admitted without charge. Its annual budget is around $1.2 billion, with two-thirds coming from annual federal appropriations. Other funding comes from the Institution’s endowment, private and corporate contributions, membership dues, and earned retail, concession, and licensing revenue. Institution publications include Smithsonian and Air & Space magazines.

    Research centers and programs

    The following is a list of Smithsonian research centers, with their affiliated museum in parentheses:

    Archives of American Art
    California State Railroad Museum
    Carrie Bow Marine Field Station (Natural History Museum)
    Center for Earth and Planetary Studies (Air and Space Museum)
    Center for Folklife and Cultural Heritage
    Marine Station at Fort Pierce (Natural History Museum)
    Smithsonian Migratory Bird Center (National Zoo)
    Museum Conservation Institute
    Smithsonian Asian Pacific American Center
    Smithsonian Astrophysical Observatory and the associated Harvard–Smithsonian Center for Astrophysics
    Smithsonian Conservation Biology Institute (National Zoo)
    Smithsonian Environmental Research Center
    Smithsonian Institution Archives
    Smithsonian Libraries
    Smithsonian Institution Scholarly Press
    Smithsonian Latino Center
    Smithsonian Provenance Research Initiative (SPRI)
    Smithsonian Science Education Center
    Smithsonian Tropical Research Institute (Panamá)
    Woodrow Wilson International Center for Scholars

    Also of note is the Smithsonian Museum Support Center (MSC), located in Silver Hill, Maryland (Suitland), which is the principal off-site conservation and collections facility for multiple Smithsonian museums, primarily the National Museum of Natural History. The MSC was dedicated in May 1983. The MSC covers 4.5 acres (1.8 ha) of land, with over 500,000 square feet (46,000 m^2) of space, making it one of the largest set of structures in the Smithsonian. It has over 12 miles (19 km) of cabinets, and more than 31 million objects.

     
  • richardmitnick 10:28 am on November 17, 2020 Permalink | Reply
    Tags: "A Tiny Atlantic Island Just Protected a Giant Pristine Stretch of the Ocean", , , , Smithsonian.com   

    From smithsonian.com and natgeo.com: “A Tiny Atlantic Island Just Protected a Giant, Pristine Stretch of the Ocean” 

    smithsonian
    From smithsonian.com

    and

    National Geographic

    natgeo.com

    November 16, 2020
    Rasha Aridi

    Tristan da Cunha fully protected 90 percent of its waters, safeguarding its vibrant biodiversity.

    1
    A remarkable abundance of wildlife reside on or around the territory’s four islands, including endangered yellow-nosed albatross, sevengill sharks, rockhopper penguins and 11 species of whales and dolphins. Credit:Brian Gratwicke via Wikimedia Commons under CC BY 2.0)

    The government of Tristan da Cunha, a tiny British territory in the middle of the southern Atlantic Ocean, took a major step forward in marine conservation last week when it established the largest marine protected area (MPA) in the Atlantic and the fourth largest in the world, reports Sarah Gibbens for National Geographic.

    Now, this four-island archipelago will be the site of a marine sanctuary that spans 265,347 square miles, making it almost three times larger than the United Kingdom. Announced today by the Tristan da Cunha government, 90 percent of the waters around the island chain will become a “no-take zone” in which fishing, mining, and other extractive activities are banned.

    Not only will this help bolster a small lobster fishery outside the sanctuary, say conservationists, but also it will protect foraging grounds for the tens of millions of seabirds that roost on the islands, such as yellow-nosed albatross and rockhopper penguins, and habitat for seals, sharks, and whales.

    The new protected area will join the U.K.’s Blue Belt Programme, which, as of today, safeguards 2.7 million square miles of marine ecosystems around the world. The new sanctuary is the result of a collaboration between the Tristan da Cunha and U.K. governments, and a number of other conservation groups, including RSPB, which has worked in the region for 20 years, and the National Geographic’s Society’s Pristine Seas initiative.

    The establishment of this MPA will fully protect 90 percent of Tristan da Cunha’s waters, a total of 265,347 square miles—an area larger than the state of Texas. The MPA has been designated as a “no-take zone,” so all fishing, mining and extraction is prohibited. Fully protected, no-take MPAs are rare—they only safeguard 2.6 percent of the ocean. Altogether, MPAs only make up around 8 percent of the ocean, reports National Geographic.

    2
    Credit: Christine Fellenz, Irene Berman-vaporis, AND TAYLOR MAGGIACOMO, ngm Staff. Sources: Pristine Seas, National Geographic Society; Environmental Market Solutions Lab, UC Santa Barbara; Trisha Atwood, Utah State University.

    Located halfway between South Africa and Argentina, Tristan da Cunha is home to around 250 residents nearly, making it one of the most remote inhabited islands on Earth. A remarkable abundance of wildlife also resides on or around the territory’s four islands, including endangered yellow-nosed albatross, sevengill sharks, rockhopper penguins and 11 species of whales and dolphins, reports Danica Kirka for the Associated Press. Protecting the ocean doesn’t just protect the creatures in the water; it also safeguards the feeding grounds of millions of seabirds that inhabit the islands, reports National Geographic.

    “Tristan da Cunha is a place like no other,” Beccy Speight, the chief executive of the Royal Society for the Protection of Birds in the United Kingdom, says in an announcement from Tristan da Cunha’s government. “The waters that surround this remote U.K. Overseas Territory are some of the richest in the world. Tens of millions of seabirds soar above the waves, penguins and seals cram onto the beaches, threatened sharks breed offshore and mysterious whales feed in the deep-water canyons. From today, we can say all of this is protected.”

    Jutting from this main island is an active volcano that’s capped with snow in the winter and marked by steep cliffs where albatross build their nests. Along the beaches are colonies of seals and penguins, and just offshore lie golden kelp forests. Only one tree species exists on the island, phylica arborea, or “the island tree.”

    This move is part of the U.K.’s Blue Belt Program, an initiative to establish MPAs in its territories as part of the global movement to safeguard nearly a third of the world’s land and ocean, reports Karen McVeigh for The Guardian.

    Earlier this year, the United Nations presented a new biodiversity plan that called to protect 30 percent of the planet by 2030. Doing so will shelter biodiversity from extinction, create a healthier planet and give nature space to mitigate the effects of climate change. This plan came out less than a year after scientists issued a study and warned that one million species are on the path to extinction.

    The Edinburgh of the Seven Seas

    In a 2014 article that appeared in the now shuttered U.S. edition of National Geographic Traveler magazine, writer Andy Isaacson described Tristan da Cunha—or simply Tristan, as it’s often called—as a mix between Scotland and California’s Big Sur.

    Jutting from this main island is an active volcano that’s capped with snow in the winter and marked by steep cliffs where albatross build their nests. Along the beaches are colonies of seals and penguins, and just offshore lie golden kelp forests. Only one tree species exists on the island, phylica arborea, or “the island tree.”

    About 245 people of Scottish, American, Dutch, and Italian heritage live in Tristan’s only village, called Edinburgh of the Seven Seas.

    First discovered by Portuguese explorer Tristão da Cunha in 1506, the island wasn’t inhabited until 1816, when a British garrison was stationed there to prevent the French from rescuing exiled emperor Napoleon from St. Helena Island, 1,343 miles north.

    The descendants of those British sailors and a smattering of others over the years populate the island, keeping sheep, growing potatoes, and fishing for lobster.

    While humans are scarce, wildlife is abundant on Tristan da Cunha, with seabird populations numbering in the tens of millions.

    Every evening on the island, “the air just looks like it’s black with smoke as birds descend,” says Hall. “The scale of life is just so amazing.”

    During a 2017 expedition to research the archipelago, scientists from National Geographic Pristine Seas also discovered a large population of migratory blue sharks, a species that’s heavily overfished for their fins.

    “This is a place that has a unique ecosystem that is found nowhere else,” says National Geographic Explorer-in-Residence Enric Sala. It’s the only region for thousands of miles with coastal ecosystems like kelp forests, he notes, and it’s a critical nursery for blue sharks.

    Benefits from marine protection

    As remote as it is, Tristan da Cunha is not without its conservation threats. Invasive mice, brought by passing ships, kill about two million birds a year. The first eradication program will take place in 2021.

    Offshore, RSPB’s Hall says the region has seen illegal fishing vessels. Tristan da Cunha’s residents operate a lobster fishery that’s certified as sustainable by the Marine Stewardship Council. The new marine reserve excludes the designated fishing zones just offshore several islands. Inside the marine reserve, no fishing will be permitted.

    A 2017 report by Pristine Seas used satellite data to track fishing vessels in the area from 2014 to 2016. A majority of the 253 vessels logged appeared to be passing through, but 11 showed activity consistent with fishing. Industrial fishing can lead to seabirds, sharks, and other important species inadvertently caught in nets or on fishing lines.

    Under the protection of the U.K.’s Blue Belt Programme, Tristan da Cunha will receive more resources for patrolling its waters for illegal fishing activity, says Hall.

    Marine protected areas (MPAs) are seen by experts as a conservation silver bullet. A study published on Tuesday in the Proceedings of the National Academy of Sciences further corroborated established scientific evidence that MPAs worldwide protect food supplies by producing larger catch yields. Fisheries that are left undisturbed can produce a “spillover” effect in which an abundance of fish from a protected area “spill over” into fishing hotspots. Expanding the current network of protected areas by just 5 percent, the study found, could boost global fish catch by at least 20 percent.

    “The increasing demand for seafood from an increasing and burgeoning human population, in addition to the expected negative impacts of climate change on many fisheries, elevates the need for managing and protecting fish stocks well,” says Reniel Cabral, an ecologist at the University of California, Santa Barbara, and one of the study’s authors.

    More to do

    Around 8 percent of the world’s oceans are designated as MPAs, but only 2.6 percent are totally off limits to fishing.

    The National Geographic Society’s Campaign for Nature Initiative has called for 30 percent of the ocean to be protected, a figure their research shows would allow ecosystems to provide benefits like ample fish stocks. Safeguarding that much of the ocean, they say, will also help protect critically endangered species from extinction.

    “We have 10 years to protect 30 percent of the ocean if we want to stop the extinction of species,” says Sala.

    He says these protected areas must be in large pristine areas like the waters around Tristan, but he notes that the world needs a larger number of small MPAs in parts of the world with more active commercial fisheries, like the U.S. and Mediteranean.

    See the full Smithsonian article here .
    See the full natgeo article here.

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  • richardmitnick 12:43 pm on November 11, 2020 Permalink | Reply
    Tags: "Scientists release genomes of birds representing nearly all avian families", , Since the first bird evolved more than 150 million years ago its descendants have adapted of ecological niches giving rise to tiny hovering hummingbirds plunge-diving pelicans and birds-of-paradise., Smithsonian.com   

    From smithsonian.com via phys.org: “Scientists release genomes of birds representing nearly all avian families” 

    smithsonian
    From smithsonian.com

    via


    phys.org

    November 11, 2020

    1
    Approximately 40% of the newly sequenced bird genomes were obtained using tissue samples preserved in the National Museum of Natural History’s Avian Genetic Resources Collection, which started in 1986 and has since become part of the Smithsonian’s Global Genome Initiative biorepository.In the Nov. 11 issue of the journal Nature, scientists from the Smithsonian Institution, the University of Copenhagen (DK), BGI-Shenzen (CN), the University of California, Santa Cruz and approximately 100 other institutions report on the genomes of 363 species of birds, including 267 that have been sequenced for the first time. The studied species represent more than 92% of the world’s avian families. The data from the study will advance research on the evolution of birds and aids in the conservation of threatened bird species. Credit: Chip Clark, Smithsonian.

    Since the first bird evolved more than 150 million years ago, its descendants have adapted to a vast range of ecological niches, giving rise to tiny, hovering hummingbirds, plunge-diving pelicans and showy birds-of-paradise. Today, more than 10,000 species of birds live on the planet—and now scientists are well on their way to capturing a complete genetic portrait of that diversity.

    Together, the data constitute a rich genomic resource that is now freely available to the scientific community. The release of the new genomes is a major milestone for the Bird 10,000 Genomes Project (B10K), an international collaboration organized by researchers at the Smithsonian’s National Museum of Natural History, the Kunming Institute of Zoology (CN), the Institute of Zoology in Beijing (CN), the University of Copenhagen (DK), The Rockefeller University, BGI-Shenzen (CN), Curtin University (AU), the Howard Hughes Medical Institute, Imperial College London (UK) and the Natural History Museum of Denmark (DK), which aims to sequence and share the genome of every avian species on the planet.

    2
    Approximately 40% of the newly sequenced bird genomes were obtained using tissue samples preserved in the National Museum of Natural History’s Avian Genetic Resources Collection, which started in 1986 and has since become part of the Smithsonian’s Global Genome Initiative biorepository.In the Nov. 11 issue of the journal Nature, scientists from the Smithsonian Institution, the University of Copenhagen (DK), BGI-Shenzen (CN), the University of California, Santa Cruz and approximately 100 other institutions report on the genomes of 363 species of birds, including 267 that have been sequenced for the first time. The studied species represent more than 92% of the world’s avian families. The data from the study will advance research on the evolution of birds and aids in the conservation of threatened bird species. Credit: Donald E. Hurlbert, Smithsonian.

    “B10K is probably the single most important project ever conducted in the study of birds,” said Gary Graves, curator of birds at the National Museum of Natural History and one of B10K’s seven organizers. “We’re not only hoping to learn about the phylogenetic relationships among the major branches of the tree of life of birds, but we’re providing an enormous amount of comparative data for the study of the evolution of vertebrates and life itself.”

    Comparing genomes across bird families will enable B10K researchers and others to explore how particular traits evolved in different birds, as well as to better understand evolution at the molecular level. Ultimately, B10K researchers aim to build a comprehensive avian tree of life that charts the genetic relationships between all modern birds. Such knowledge will not only reveal birds’ evolutionary past but will also be vital in guiding conservation efforts in the future.

    More than 150 ornithologists, molecular biologists and computer scientists came together to obtain specimens and analyze more than 17 trillion base pairs of DNA for the family-level phase of the B10K project. Sequencing and analysis began in 2011, but the data represent several decades of work by field collectors and collections management staff who have collected and preserved birds from every continent, Graves said.

    4
    More than 150 ornithologists, molecular biologists and computer scientists came together to obtain specimens and analyze more than 17 trillion base pairs of DNA. Sequencing and analysis began in 2011, but the data represent decades of work by field collectors and collections management staff who have collected and preserved birds from every continent. The scenes pictured above represent field work conducted by Smithsonian teams in Africa, Asia, North America and South America.In the Nov. 11 issue of the journal Nature, scientists from the Smithsonian Institution, the University of Copenhagen (DK), BGI-Shenzen (CN), the University of California, Santa Cruz and approximately 100 other institutions report on the genomes of 363 species of birds, including 267 that have been sequenced for the first time. The studied species represent more than 92% of the world’s avian families. The data from the study will advance research on the evolution of birds and aids in the conservation of threatened bird species. Credit: Christina A. Gebhard, Smithsonian.

    Approximately 40% of the newly sequenced bird genomes were obtained using tissue samples preserved in the National Museum of Natural History’s Avian Genetic Resources Collection, which Graves started in 1986 and has since become part of the Smithsonian’s Global Genome Initiative biorepository. Also contributing to the project were Michael Braun, a research zoologist at the National Museum of Natural History; Rebecca Dikow, who leads the Smithsonian Data Science Lab; and researchers with the Smithsonian’s National Zoo and Conservation Biology Institute and the Smithsonian Tropical Research Institute in Panama.

    “It might seem that having a genome for each bird family or species is a bit like stamp collecting, but this massive cooperative effort has given us a set of very important genomic resources for conservation,” said Rob Fleischer, one of the authors and head of the Smithsonian Conservation Biology Institute’s Center for Conservation Genomics. “For example, it provides a ready source of genetic markers useful to map population declines, identify kin and reduce inbreeding when managing rescue populations of endangered species. Having the genomes simplifies the search for genes responsible for important survival traits such as resistance to deadly introduced diseases.”

    “Through 34 years of field work and dozens of expeditions, we were able to get the stockpile of high-quality DNA that actually makes this project possible,” Graves said. “Many of those resources were stored long before DNA sequencing technology had been developed, preserved for future analyses their collectors could not have imagined at the time. It’s one of the many reasons why natural history museum collections and museum-based research programs are so important!”

    With 363 genomes complete, B10K is expanding its efforts to encompass the next level of avian classification. In this phase, the team will sequence thousands of additional genomes, aiming to represent each of the approximately 2,300 genera of birds.

    Science paper:
    Dense sampling of bird diversity increases power of comparative genomics
    Nature

    See the full article here .
    See further the full article from UCSC here .

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  • richardmitnick 10:31 am on October 1, 2020 Permalink | Reply
    Tags: "How NASA’s New Telescope Will Help Astronomers Discover Free-Floating Worlds", , , , , Smithsonian.com,   

    From smithsonian.com: “How NASA’s New Telescope Will Help Astronomers Discover Free-Floating Worlds” 

    smithsonian
    From smithsonian.com

    September 30, 2020
    Nola Taylor Redd

    NASA Nancy Grace Roman Space Telescope.

    The Nancy Grace Roman Space Telescope will be able to detect small, distant planets without stars.

    As astronomers discover more and more planets in galaxies far, far away, they are increasingly confronted with a curious subset of orbs that are free-floating and not connected to or orbiting a particular star. Further complicating matters is that within that group, most of what they have found are gassy, Jupiter-sized (read: large), planets; few resemble rockier planets like our own Earth.

    First discovered in 2003, these potential free-floating planets are elusive and difficult to detect from the existing ground-based observatories.

    Soon, however, a revolutionary new telescope launching in 2025 may be able unlock the secrets of the darkness of space, where sunless worlds may even outnumber the stars. NASA’s Nancy Grace Roman Space Telescope will be able to see even more rocky free-floating planets, potentially hundreds as small as Mars, according to research published this August in The Astronomical Journal. These lightless worlds can shine light on how planets formed and what happens to them after their star finally dies.

    “The galaxy could be teeming with these free-floating planets, or maybe none,” says Scott Gaudi, an astronomer at Ohio State University and an author on the new research. “There could be more Earth-mass planets than stars in the galaxy…Now we’ll have the possibility with Roman to figure that out.”

    The Nancy Grace Roman Space Telescope, named after NASA’s first chief astronomer who tirelessly advocated for new tools like Hubble and made several important contributions to the field of astronomy, will engage in a trio of core surveys. Roman will study dark energy, survey a special type of supernovae and discover numerous exoplanets through a technology known as gravitational microlensing.

    Gravitational microlensing, S. Liebes, Physical Review B, 133 (1964): 835.

    This technique can reveal objects too dark to discover through other means, objects such as black holes or planets. When an object, like a planet, passes in front of a star, its gravity causes a very slight brightening to the stellar light. The faint magnification, predicted by the theory of general relativity, can provide insights into the passing magnifier. Unlike most other planetary discovery techniques, microlensing can find worlds cast off from their star, drifting through the darkness of space.

    “Microlensing can find planets from a little past Earth to the center of the galaxy,” says Samson Johnson, a graduate student at Ohio State University and first author on the new research. “It can find planets all throughout the galaxy.”

    The technique has its own limitations. Once a planet completes the lensing process, it continues to drift through the darkness of space, never to be seen again from Earth. But Johnson says that’s not a huge problem—after all, astronomy is full of transient, one-time events. “You don’t ask a supernova to explode again, you don’t ask black holes to re-merge,” he says.

    While free-floating planets may saturate space, finding them is something of a crapshoot. The process requires three objects—Earth, the background star, and the undiscovered mystery object—line up precisely. Rather than looking at a single star and waiting for the odds to be in their favor, astronomers instead perform massive surveys watching hundreds of millions of stars at the same time for the subtle brightening caused by microlensing. These enormous surveys allow astronomers to discover as many as 2,000 to 3,000 potential microlensing events each year, only a handful of which are wandering planets, according to microlensing observer Przemek Mroz, an astronomer at CalTech who was not part of the new research.


    NASA’s Nancy Grace Roman Space Telescope: Broadening Our Cosmic Horizons

    Earth’s atmosphere creates interference than can make these small events difficult to observe. What sets Roman apart is that it will be orbiting in space, allowing it watch for even briefer microlensing events that represent smaller planets. Additionally, since most such telescope surveys are performed using optical light, the part of the spectrum that humans see with their eyes, they cannot peer through the dust in the center of the galaxy. Roman will rely on infrared light rather than optical, allowing it to peer into the heart of the galaxy, dramatically increasing its ability to discover free-floating worlds.

    New Earth-sized worlds discovered by Roman can help researchers understand the messy process of planet formation. Previous solar system observations led scientists to suspect that the giant planets, especially Jupiter, used their gravity to hurl some of the planetary embryos and young planets out of the solar system, a process likely repeated in other systems. Roman can help to spot some of those lost worlds and determine roughly how many were ejected.

    But planets aren’t only lost during the first moments of their lives. Passing stars can wrangle away worlds that are only loosely connected to their star. A parent star can also drive away its planetary children as it evolves. In a few billion years, our own sun will swell up to a red giant, shedding enough stellar material that its gravitational hold on its planets will weaken, allowing some to wander away.

    Some planets may even form without the help of a star. Recent studies suggest that a small enough pocket of gas and dust could collapse to form not a star but a gas giant.

    While scientists can’t verify the source of a single free-floating planet because none of the ejection processes leave their fingerprint on the world, a statistical look at the population should provide its own insights. Enter Roman, which will discover a wealth of new starless worlds. “If we find a bunch of Earth-mass planets, they almost certainly formed around a star,” Gaudi says, because self-forming planets require more mass.

    Roman’s observations should provide insights about the free-floating worlds and how they became wanderers in space. “We’re starting to run into the limit of what we can do from the ground with ground-based microlensing surveys,” Gaudi says. “That’s why we need to go to space and use Roman.”

    See the full article here .

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  • richardmitnick 10:25 am on March 12, 2020 Permalink | Reply
    Tags: "A Buffer Zone Around Saturn May Have Kept It From Swallowing Its Biggest Moon", A few moons are thought to be the shrapnel from collisions between much bigger bodies while others may be hostages captured from elsewhere in space by a planet’s gravitational pull., , , , , Smithsonian.com, The science team discovered that planets like Saturn are in fact capable of gobbling up their moons—but only if they fall within a certain distance., Titan may have been the only survivor of a feeding frenzy during Saturn’s early evolution during which the ringed planet gobbled up similarly-sized moons orbiting closer to its surface.   

    From smithsonian.com: “A Buffer Zone Around Saturn May Have Kept It From Swallowing Its Biggest Moon” 

    smithsonian
    From smithsonian.com

    March 11, 2020
    Katherine J. Wu

    A new simulation points to a previously untold chapter in Titan’s history.

    1
    An artist’s impression of a moon forming around a young planet (Nagoya University).

    Among Saturn’s exceptional entourage of 82 moons, one stands out: Titan, a hulking giant that, at 3,200 miles across, besting even the planet Mercury in width. Researchers have long struggled to explain why only one of Saturn’s satellites—the second largest moon in our solar system—reached such gargantuan proportions.

    Now, a team of planetary scientists has come up with a new theory on how this bulky behemoth became a solo act. Titan, they argue, may have been the only survivor of a feeding frenzy during Saturn’s early evolution, during which the ringed planet gobbled up similarly-sized moons orbiting closer to its surface.

    The findings, published this week in Astronomy and Astrophysics, represent the first demonstration “that a system with only one large moon around a giant planet can form,” study author Yuri Fujii of Nagoya University explains in a statement.

    “We demonstrated for the first time that a system with only one large moon around a giant planet can form,” says Fujii. “This is an important milestone to understand the origin of Titan.”

    But Ogihara cautions, “It would be difficult to examine whether Titan actually experienced this process. Our scenario could be verified through research of satellites around extrasolar planets. If many single-exomoon systems are found, the formation mechanisms of such systems will become a red-hot issue.”

    On the whole, moon formation remains a mysterious business. Many likely formed alongside their parent bodies, sprouting out of the swirling disk of gas and dust that wreathes planets in their infancy. A few are thought to be the shrapnel from collisions between much bigger bodies, while others may be hostages, captured from elsewhere in space by a planet’s gravitational pull.

    Simulations have shown that when a large moon like Titan, distinct from its much smaller lunar siblings, ends up in the vicinity of a planet like Saturn, it will simply get swallowed up—suggesting that researchers’ models of moon evolution have been overly simplistic, Fujii tells Nadia Drake at the New York Times.

    To refine their understanding of Titan’s origins, Fujii and her colleagues created a model that more accurately captured the dynamics within Saturn’s gassy, dusty halo. Their data added information about temperature and density gradients, while also factoring in other variables such as the gravity of nearby moons, reports Jennifer Leman for Popular Mechanics.

    After running their simulation over more than 100,000 years of moon evolution, the team discovered that planets like Saturn are, in fact, capable of gobbling up their moons—but only if they fall within a certain distance. Within that radius, moons will end up moving inward and getting swallowed early on. But just outside this zone of terror lies a thick buffer—a ring with a steep temperature gradient that drops off precipitously at its outer edge. Warm, high pressure gas within the band pushes any moons that exist outside it away from the planet, instead of pulling them toward it. Circling Saturn from afar, Titan may have been spared the grisly fate that claimed others of its kind.

    Of course, this scenario doesn’t guarantee the formation of one giant moon, flanked by a gaggle of 81 runts, like Saturn has. The researchers also can’t prove that Titan actually did form this way. As such, the simulations are “interesting, but preliminary,” Luke Dones, a planetary scientist at the Southwest Research Institute tells the New York Times.

    Other aspects of Titan’s history remain mysterious as well. Though the researcher’s findings could help explain how the moon survived, they leave open a variety of possibilities for how it formed and came to orbit Saturn in the first place.

    See the full article here .

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  • richardmitnick 12:38 pm on January 11, 2020 Permalink | Reply
    Tags: "Crater From Giant Meteorite Strike Might Be Hidden Under Volcanic Plateau", Although the evidence they present is thorough it’s not quite rock-solid., , , Earth Observatory of Singapore, , New York Times, PNAS, Smithsonian.com, The first clue to the meteorite’s impact site came from the bits of glassy debris called tektites that it launched into the air about 800000 years ago., Ultimately a lava field in southern Laos turned up promising results.,   

    From smithsonian.com: “Crater From Giant Meteorite Strike Might Be Hidden Under Volcanic Plateau” 

    smithsonian
    From smithsonian.com

    January 10, 2020
    Theresa Machemer

    1
    A large meteorite can launch bits of molten rock into the atmosphere when it impacts Earth. When that molten rock cools, it forms tektites, shown here. (Photo by Robert Eastman / Alamy Stock Photo)

    Debris from the strike scattered across Earth, but the exact point of impact has been a mystery.

    The impact of a meteorite ranges from an Alabama woman’s giant bruise to the end of the dinosaurs. But one meteorite’s crater has eluded scientists for almost a century, despite the fact that it scattered glass confetti across one-tenth of the Earth’s surface. Now, experts at the Earth Observatory of Singapore have released a study, published in the Proceedings of the National Academy of Sciences, providing new evidence for the crater’s location.

    The first clue to the meteorite’s impact site came from the bits of glassy debris, called tektites, that it launched into the air about 800,000 years ago. The tektites landed across Antarctica, Australia and Asia, so geologist Kerry Sieh searched for signs of the crater in satellite imagery. Sieh’s search has taken years and led him down many dead-ends, Katherine Kornei reports for the New York Times-Hints of Phantom Crater Found Under Volcanic Plateau in Laos, but ultimately a lava field in southern Laos turned up promising results. There, volcanic eruptions long ago covered the land in molten rock, building a layer of igneous rock up to 1,000 feet deep, which could have easily obscured the impact crater.

    The research team began by analyzing previously published chemical characteristics of tektites found in Australia and Asia, and found evidence linking them to the Laotian lava field. They then estimated the age of the tektites and lava flows—the lava at the suspect site was younger than the lava around it—and measured the local gravitational field of the lava bed. Craters are often filled with less dense material that was broken apart on impact, and Sieh’s findings of a weaker gravitational pull provide more evidence of the impact crater’s existence.

    “There have been many, many attempts to find the impact site,” Sieh tells CNN’s Michelle Lim [A huge meteorite smashed into Earth nearly 800,000 years ago. We may have finally found the crater]. “But our study is the first to put together so many lines of evidence, ranging from the chemical nature of the tektites to their physical characteristics, and from gravity measurements to measurements of the age of lavas that could bury the crater.”

    By the new study’s calculations, the meteorite was about 1.2 miles wide and created a crater 8 miles wide and 11 miles long. It would have struck our planet at a speed fast enough to melt the Earth beneath it, material that was thrown into the air to create tektites. The impact also would have sent boulders flying at 1,500 feet per second, Leslie Nemo writes for Discover [Found: Crater From Asteroid Impact That Covered 10% of Earth’s Surface in Debris], some of which Sieh spotted in a hill that was cut through by a road a few miles away from the suspected impact site.

    Although the evidence they present is thorough, it’s not quite rock-solid. In a commentary [PNAS] that accompanied the study, impact crater expert Henry Melosh writes that Sieh and his team “present the best candidate yet for the long-sought source crater,” but adds, “one of my impact-savvy colleagues read the paper and was unconvinced. As with all possible impact craters, proof will rest on finding shock-metamorphosed rocks, minerals, and melt.”

    Melosh points out that the crater is smaller than previously expected for this meteorite, and that it would have had to land at an unusually shallow angle to create the oval shape that Sieh’s team proposes. To provide the strongest evidence that this is the crater they’ve been looking for, scientists would have to drill through the lava flows, which are in a tropical jungle, and recover rock samples from below.

    Sieh tells Nemo that he would be supportive of anyone who wants to complete that work.

    See the full article here .

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  • richardmitnick 11:08 am on January 4, 2020 Permalink | Reply
    Tags: "The Complicated Role of Iron in Ocean Health and Climate Change", , , , Smithsonian.com   

    From smithsonian.com: “The Complicated Role of Iron in Ocean Health and Climate Change” 

    smithsonian
    From smithsonian.com

    January 3, 2020
    Emily Underwood

    Iron dust may have played a significant role in the last ice age, and it could be an important factor in mitigating future global temperature increases.

    1
    Iron-rich dust launched into the air by winds swirls around the Southern Ocean. Understanding how iron’s chemistry shifts during its journey from earth to air to sea will be important for developing better climate models. (William Putnam and Arlindo da Silva, NASA / Goddard Space Flight Center)

    One brisk day in April 2013, as he drove with colleagues along the southern coast of Patagonia, Mike Kaplan spotted a geologist’s treasure trove—an active gravel pit with freshly exposed walls. He pulled over, grabbed the backpack full of digging tools stowed in the car trunk and walked into the large hole.

    To Kaplan’s south lay the Southern Ocean, stretching toward Antarctica. Strewn around him was evidence of Earth’s most recent ice age: heaps of crushed rock and gravel released by one of the many glaciers that had once covered North and South America. Standing in the pit, Kaplan spotted what he was looking for: a layer of fine gray silt deposited by ice sheets roughly 20,000 years ago.

    A geologist at Columbia University in New York, Kaplan has spent over a decade collecting the sediments that make dust, and studying how that dust, launched from earth to air to sea, influences Earth’s climate, past and present. Dozens of intriguing samples have made their way home with him, stowed in his suitcase or shipped in a duct-taped cardboard box. As he scraped the dark gray sediment into a plastic bag, he felt a rush of anticipation. Given the sample’s location, he thought that it might be just what he needed to test an aspect of a controversial idea known as the iron hypothesis.

    Proposed in 1990 by the late oceanographer John Martin, the hypothesis suggests that flurries of dust — swept from cold, dry landscapes like the glacial outwash where Kaplan now stood, trowel in hand — played a crucial role in the last major ice age. When this dust landed in the iron-starved Southern Ocean, Martin argued, the iron within it would have fertilized massive blooms of diatoms and other phytoplankton. Single-celled algae with intricate silica shells, diatoms photosynthesize, pulling carbon from the atmosphere and transforming it to sugar to fuel their growth. Going a step further, Martin proposed that using iron to trigger diatom blooms might help combat global warming. “Give me half a tanker of iron and I’ll give you an ice age,” he once said half-jokingly at a seminar, reportedly in his best Dr. Strangelove accent.

    Thirty years after Martin’s bold idea, scientists are still debating just how much iron dust contributed to the ice age, and whether geoengineering of the oceans—a prospect still lobbied for by some—might actually work. Although it’s now well-established that an uptick in iron fertilization occurred in the Southern Ocean during the last major ice age, for example, scientists still argue about how much it reduced carbon dioxide levels in the atmosphere. And while Martin’s hypothesis inspired 13 large iron fertilization experiments that boosted algae growth, only two demonstrated removal of carbon to the deep sea; the others were ambiguous or failed to show an impact, says Ken Buesseler, a marine radiochemist at the Woods Hole Oceanographic Institution in Massachusetts.

    In 2008, concerns about possible environmental impacts of iron fertilization, such as toxic algal blooms and damaged marine ecosystems, prompted the United Nations Convention on Biological Diversity to place a moratorium on all large-scale ocean fertilization experiments. The ban “put the kibosh” on such activity, says Buesseler. The problem with that, many scientists now contend, is that the most fundamental questions about iron fertilization—if it can sequester enough carbon to alter climate, and what its environmental consequences would be—remain unanswered.

    As atmospheric carbon levels soar past 400 parts per million, some researchers believe that the freeze on iron fertilization experiments should be reconsidered, Buesseler among them. “I’m not a supporter of geoengineering, but I think it is our responsibility to look” at ways of actively removing carbon from the atmosphere, including iron fertilization, he says.

    Whether people ever decide to pursue iron fertilization to combat climate change or not, scientists still need to understand the environmental impacts of iron-rich dust and ash from natural sources like volcanoes, and from manmade pollutants, says Vicki Grassian, a physical chemist at the University of California, San Diego. To meet that challenge, labs around the world are studying how iron affects climate and ocean health. Their work spans the scales, from the tiny crystalline structure of iron-peppered nanoparticles to large-scale simulations of global climate. Ultimately, scientists hope to understand the role of iron dust in marine systems, says Kristen Buck, a chemical oceanographer at the University of South Florida. “When you add iron to a system, how does that trigger the system to change?”

    In ancient seas, iron aplenty

    To learn how iron fertilization might work in the future, some researchers are looking at the past, in paleoclimate records such as ice cores and deep-sea sediments. From that perspective, many of the natural iron fertilization experiments have already been run, says Gisela Winckler, a climate scientist at the Lamont-Doherty Earth Observatory at Columbia, and Kaplan’s colleague.

    Three billion years ago the ocean was chock-full of iron, ancient mineral deposits show. Iron was plentiful when life first evolved, and the metal was incorporated into a long list of essential cellular functions. Animals need iron to transport oxygen in their blood and to break down sugar and other nutrients for energy. Plants need iron to transfer electrons during photosynthesis and to make chlorophyll. Phytoplankton need it to “fix” nitrogen into a usable form.

    2
    Ancient layers of iron oxides, typically magnetite or hematite, separated by chert (a type of quartz), form sedimentary rocks called banded iron formations. (One shown here from Fortescue Falls in Western Australia.) It’s thought that iron, once abundant in the oceans, began to form such deposits on the ocean floor between 2.5 billion and 1.9 billion years ago, as oxygen levels rose. (Graeme Churchard via Wikipedia Commons under CC BY 2.0)

    Despite being the fourth most abundant element in the Earth’s crust, iron is vanishingly scarce in the modern ocean. It started disappearing from the seas more than 2.4 billion years ago, when cyanobacteria evolved and started to breathe in carbon dioxide and exhale oxygen. When this happened, dissolved iron rapidly linked up with the newly plentiful oxygen atoms, forming iron oxides such as hematite, a common mineral that contains a form of the element known as iron(III). Most phytoplankton and other living organisms can’t use iron in this state. They require a different form, iron(II), which more readily dissolves and is absorbed by cells.

    Hematite has another downside: It sinks. Over billions of years, layer upon layer fell to the sea floor, forming iron ore deposits hundreds to thousands of feet deep. Meanwhile, iron in the waters above diminished to barely detectable levels—an average liter of seawater contains roughly 35 grams of salt, but only on the order of a billionth of a gram of iron. In roughly a third of the ocean, iron is so rare that its absence can hinder the growth of diatoms and other phytoplankton. The Southern Ocean, where Martin developed his hypothesis, is one of the most “iron-limited” oceans in the world. Even with an abundance of other crucial nutrients such as nitrogen and phosphorus, it’s the availability of iron that matters for diatoms and other organisms.

    Unless, of course, a gust of wind delivers a plume of iron particles. Standing in the freshly excavated gravel pit in Patagonia, Kaplan was directly upwind of the Southern Ocean—close to where Martin proposed that ice age dust had helped to fertilize the ocean some 20,000 years ago. It was the perfect place to test whether those iron-rich glacial sediments would have made a good fertilizer for diatoms. Researchers already knew that there was more dust-borne iron during the last ice age, much of it freed by melting glaciers. But no one had yet rigorously tested whether the iron was in the form that diatoms can absorb, Kaplan says.

    Kaplan scraped up the dark gray silt and brought it back to Columbia, where he handed it off to then-graduate student Elizabeth Shoenfelt Troein, who is now a postdoctoral fellow at the Massachusetts Institute of Technology. Shoenfelt Troein flew out to the Stanford Synchrotron Radiation Lightsource in Menlo Park, California. There, along with her adviser Benjamin Bostick and fellow graduate student Jing Sun, she spent many long nights zapping the sediment with high-powered X-rays to reveal its mineral composition.

    Kaplan scraped up the dark gray silt and brought it back to Columbia, where he handed it off to then-graduate student Elizabeth Shoenfelt Troein, who is now a postdoctoral fellow at the Massachusetts Institute of Technology. Shoenfelt Troein flew out to the Stanford Synchrotron Radiation Lightsource in Menlo Park, California. There, along with her adviser Benjamin Bostick and fellow graduate student Jing Sun, she spent many long nights zapping the sediment with high-powered X-rays to reveal its mineral composition.

    Only certain types of minerals yield dust that is rich in soluble forms of iron, including iron(II), the kind that diatoms can easily digest, as Grassian and colleagues described in 2008 in the Annual Review of Physical Chemistry. Clay minerals containing iron, for example, yield iron(II) more easily than hematite, as they’ve found in experiments on dust from around the world, including Africa’s Sahara Desert, Chinese loess and Saudi Arabian beach sand. Winds blowing off the Sahara are one of the most important sources of iron dust in the ocean, supplying more than 70 percent of dissolved iron to the Atlantic, another group has found. But there are several other paths by which iron(II) makes its way to the oceans, including rivers, hydrothermal vents, volcanoes and glacial outwash plains like the one where Kaplan found his sample in Patagonia.

    Iron is among the most common elements on Earth, but is rarely found in its pure metallic form (Fe). Instead, it readily reacts with oxygen to form various iron oxides, and with other elements to form a wide array of minerals. Hematite is the main source of iron used to make steel but living organisms can more readily use iron in the +2 oxidation state. Adding water to an iron oxide can create rust in what’s termed a hydrated iron oxide. (A. Murugan / New Castle University 2011)

    The glacial sediment contained far more iron(II) than samples deposited during non-glacial periods from the same region, Shoenfelt Troein found. When glaciers grind down bedrock, the resulting freshly ground sediments tend to contain more iron(II) than sediments produced from weathering by wind and water, which are richer in iron(III), Winckler says. Back at Columbia, Shoenfelt Troein fed the iron(II)–rich, glacial sediment to a common species of diatom, Phaeodactylum tricornutum, and the diatoms reproduced 2.5 times as fast as they did on weathered sediment, the team reported in Science Advances in 2017. This would translate into a roughly fivefold increase in carbon uptake compared with the non-glacial sediment, the team calculated.

    When the team looked at marine sediment cores from several glacial and interglacial periods spanning 140,000 years, Winckler, Shoenfelt Troein and colleagues found that dust from the glacial periods contained 15 to 20 times more iron(II) than did dust from the current interglacial period. That suggests that the potency of glacial sediment led to a self-reinforcing cycle, in which higher rates of iron fertilization in the oceans reduced carbon in the air, leading to colder temperatures, which in turn, grew glaciers, the team reported in the Proceedings of the National Academy of Sciences in 2018. It also suggests that not all iron is equal when it comes to fertilization, and that freshly mined, fine-ground iron might be more effective than other forms, Winckler says.

    In most of the geoengineering experiments in the 1990s and early 2000s, scientists mixed a powdered form of iron called ferrous sulfate with acidic water and fed the liquid off the back of a ship, says David Emerson, a geomicrobiologist at the Bigelow Laboratory for Ocean Sciences in Maine. The fate of ferrous sulfate once it enters the oceans is not fully known, he says, but it’s reasonable to assume that some of it oxidizes to the diatom-disdained iron(III) and sinks, even if some persists in the upper water column for days. Emerson recently proposed using aircraft to distribute a fine iron dust produced by iron-eating bacteria, called biogenic oxide. This form is composed of iron nanoparticles bound to organic compounds, and would likely stay suspended longer than ferrous sulfate in the sunlit surface waters where diatoms grow, he says.

    4
    Not all iron is equal when it comes to fertilizing diatoms. When scientists fed this common diatom species, Phaeodactylum tricornutum, a glacier-made sediment rich in soluble iron(II), the phytoplankton reproduced 2.5 times as fast as they did when fertilized with sediment that contained a less soluble form of iron. The higher growth rate would translate into a roughly fivefold increase in carbon uptake, the team calculated. (Alessandra De Martino, Ecole Normale Superieure, Paris / NSF)

    Getting iron to linger in surface waters won’t necessarily ensure that the carbon absorbed by diatoms actually reaches the deep sea, however. Roughly 90 percent of the organic carbon that diatoms create during photosynthesis is released back into the ocean in dissolved form as the algae dies, rots and is consumed by bacteria, zooplankton and fish, Buesseler says. Just 10 percent of the carbon produced by the ocean’s creatures migrates to the depths where it may remain for hundreds to thousands of years—the length of time relevant for climate mitigation. A mere 1 percent gets permanently buried on the seafloor. Critically, no iron fertilization experiment has yet lasted long enough to track how much of the carbon that diatoms do capture actually gets sequestered to the deep ocean, he says.

    Location also plays a vital role in whether iron fertilization is effective, Winckler says. Based on marine sediment cores, Winckler and her colleagues have reconstructed a 500,000-year record of iron dust levels throughout the Pacific to see if—and where—notable spikes of iron fertilization occurred in the past. The team knows how much the dust level has changed, and in parallel measures the biological responses to the dust to determine if the phytoplankton “actually cares about the change,” she says. She concludes that the iron hypothesis appears to apply only to some parts of the Southern Ocean—and not other low-iron regions the such as equatorial Pacific, where past iron fertilization experiments have boosted phytoplankton growth but failed to show the degree of carbon capture scientists had expected.

    There are many complex factors involved in determining where iron fertilization might work, including upwelling currents that deliver iron from deeper waters and the availability of other vital nutrients. Yet “people often just look at one piece of this puzzle, and then make big conclusions,” Winckler says.

    6
    Before the GEOTRACES effort to map the global sources of iron, the metal’s path was somewhat unclear. In a 2019 paper, scientists used data from GEOTRACES to “fingerprint” the origins of soluble iron in particles of dust that fall on the ocean. Human activities such as burning coal or gasoline contributed as much as 80 percent of the soluble iron that landed on the sea surface throughout the world’s oceans—far more than a previous model (shown on the left) had suggested. Mineral dust swept from dry regions like the Sahara made up a smaller portion of the ocean’s iron. (T.M. Conway et al / Nature Communications 2019 under CC BY 4.0)

    Grassian studies yet another factor that can influence iron fertilization in unexpected ways: the chemical reactions that transform particles containing iron as they fly through the sky, exposed to air, water and sunlight. At her lab in San Diego, she simulates the effects of water vapor and airborne pollutants on iron particles. She and her colleagues have discovered that chemicals like sulfur dioxide and nitric acid make iron more soluble—and thus easier for diatoms to absorb—by coating them in acid.

    Iron particles produced by manmade pollution are also potent fertilizers, she and others have found. Iron flecks in coal fly ash, for example, are amorphous globs that dissolve more easily than the crystals found in mineral dust. The result is that even if you have less overall iron in coal fly ash, its impact on algae could be just as important as that of mineral dust, Grassian says.

    Iron can rapidly alter its molecular composition or state as it moves from the Earth’s crust to the ocean, and such changes determine whether iron is in a chemical form that diatoms and other photosynthetic algae can use—and thus, how much carbon they capture. Yet, for decades, climate and atmospheric chemistry models have overlooked iron’s complexity, which includes the many forms of iron present in dust as well as how dust is altered by aging and chemical exposures. “As physical chemists, we’re trying to understand the details … to get away from thinking about things in a too-simplistic fashion,” Grassian says.

    Other researchers are studying what happens when dust-borne iron dissolves into the ocean. When water molecules come up against the abrupt transition to air, many can no longer find partners for all their hydrogen bonds. As a result, one of every four water molecules has something akin to a grasping limb—a single hydroxyl (OH) group—pointing up into the air with nothing to bind to, creating an uneven chemical landscape. That variability can affect how iron transforms into one of its myriad chemical identities, and then how organisms such as diatoms interact with the metal, says Heather Allen, a physical chemist at Ohio State University.

    Sometimes iron doesn’t interact only with the water, but also encounters a millimeter-thick gel of carbohydrates, proteins and lipids known as the sea surface microlayer, or the ocean’s “skin.” This layer can concentrate trace metals such as iron, particularly when oily pollutants common along shipping routes, such as hydraulic fluids, are present, says Allen.

    Iron is so scarce in the ocean that even a bit of rust flaking off a ship’s hull can throw measurements off by a factor of 10. The instruments used to detect iron are sensitive: “If a whale poops, there goes your whole experiment,” Buck says. Through a project called GEOTRACES, Buck and an international consortium of other scientists have examined more than 20,000 measurements to map where iron comes from in the ocean, where it goes and how it changes. To avoid contamination, scientists process seawater samples in plastic-enclosed bubble labs that appear more suited to studying deadly microbes than one of Earth’s most abundant elements.

    They’ve found that most naturally produced iron dust blows off the Sahara and other deserts, but large amounts are also released in plumes of hot dissolved minerals from hydrothermal vents. Volcanoes, which can spew thousands of kilograms of iron into the atmosphere in a single eruption, are another important source. Although the evidence is circumstantial, iron fertilization from volcanic ash may have contributed to the brief hiatus in carbon buildup in the atmosphere after the 1991 eruption of the Philippines’ Mt. Pinatubo, says Emerson. Unfortunately, there was no monitoring at the time to determine if this led to a large-scale iron fertilization event, he says.

    The ocean’s iron miners

    Given how quickly iron rusts and sinks, there should be very little dissolved iron in seawater, including the highly soluble iron(II). Yet GEOTRACES has detected more of it than scientists predicted. Buck and others believe that some of these scant traces of dissolved iron can be explained by an active effort made by living things to scavenge it. In addition, they point to the presence of organic molecules called ligands, which lock up iron in a soluble, diatom-friendly form. One common example of a ligand is found in siderophores, chemical compounds that bacteria secrete to break down iron particles.

    Some organisms actively mine iron from dust. On the northernmost end of the Red Sea, for example, marine biogeochemist Yeala Shaked of the Hebrew University of Jerusalem is studying how a stringlike, reddish kind of phytoplankton called Trichodesmium takes advantage of iron-rich dust that blows in from the Sahara. This Trichodesmium species assembles into puffball-shaped colonies, each composed of tens to thousands of individual filaments. When this dust lands, the colonies shuttle the iron-rich mineral particles into the center of the colony and start extracting iron(II). A colony can transform a pool of iron(III) into iron(II) in 30 minutes, Shaked and her colleagues have found in lab experiments.

    Even small changes in the abundance and productivity of phytoplankton could have a significant impact on marine life and the rate of global warming, so organisms such as Trichodesmium are key to global climate models. An ambitious effort at MIT, for example, is attempting to incorporate many different phytoplankton species into their simulations.

    Despite iron’s assumed influence over climate, climate models still don’t currently include much detailed information about the element, says Andreas Schmittner, a climate scientist at Oregon State University. Although it’s now well-established that iron fertilization occurred in the ancient Southern Ocean, for example, there’s still lively debate over how much it affected past carbon dioxide levels. Some scientists have argued that iron fertilization wasn’t particularly important, and that most of the roughly 100 ppm drop in carbon dioxide during the last ice age can be explained by changes in ocean currents and sea ice.

    But in June 2019, Schmittner and colleagues published a different take in Science Advances, calculating that cooler temperatures and iron fertilization were responsible for most of the decrease, and ocean circulation and sea ice had “close to zero” impact, he says. Iron fertilization alone accounted for a 25 to 35 ppm decrease in atmospheric carbon during that period, “a larger effect than we expected,” he says.

    Once scientists have pieced together more about iron’s complex chemistry, they will still have to learn when to turn certain factors off and on in these climate models to accurately simulate reality, Grassian says. Better models will also depend on fine-tuning countless other factors that could affect how much carbon dioxide sequestration occurs in response to a phytoplankton bloom, including how layers of ocean water mix, and the presence of zooplankton, tiny marine organisms that graze on algae.

    Several iron fertilization experiments favored certain phytoplankton species over others, a consequence that could inadvertently reorganize marine food webs. Large algal blooms both natural and manmade have also been known to deplete oxygen in the water, creating dead zones. One risk is that iron fertilization could damage ecosystems downstream, by depriving them of nutrients that normally would have reached them, Buesseler says. “What happens when that water upwells somewhere else and [a] fishery collapses because … you’ve kind of stripped away all the juicy nutrients in one part of the ocean?”

    Meanwhile, the controversy over iron fertilization as a geoengineering approach rages on. As the vision of a climate-tweaking tool has waned, some companies have attempted to apply the idea to revitalize fisheries. In a highly controversial 2012 example, American businessman Russ George persuaded members of the Haida Nation to fund the dumping of roughly 100 tons of iron sulfate off the coast of Canada, fertilizing a 10,000-square-kilometer algae bloom. George sold the controversial project as a way to boost salmon populations and sequester carbon, but follow-up studies failed to find conclusive evidence that it worked.

    In 2013, the London Protocol, an international treaty that prevents ocean dumping, adopted amendments allowing researchers to apply for exceptions to the moratorium on iron fertilization experiments. Winckler does not advocate using iron fertilization as a geoengineering tool, but she is among those who think that more rigorous experiments are necessary to establish the approach’s efficacy and potential risks and benefits, even if people decide never to use it. “We are in a climate crisis, and we’ve got to think about these questions,” she says.

    See the full article here .

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  • richardmitnick 5:21 am on December 19, 2019 Permalink | Reply
    Tags: , , , , , , Smithsonian.com   

    From smithsonian.com: “Three Things to Know About Europe’s New Exoplanet Space Telescope” 

    smithsonian
    From smithsonian.com

    December 18, 2019
    Katherine J. Wu

    ESA/CHEOPS


    ESA/CHEOPS is the first exoplanet satellite devoted specifically to learning more about the thousands of planets we have already found.

    Home to all life as we know it, Earth certainly has a special place in our universe. But it’s probably not the only habitable planet in the cosmos—and scientists are dead set on finding and understanding as many as they can.

    Today, the European Space Agency (ESA) ratcheted up the search with the launch of its new telescope, the CHaracterising ExOPlanets Satellite (CHEOPS). Originally scheduled for liftoff from Kourou, French Guiana, on the morning of December 17, the probe’s departure was delayed at the last minute by officials citing a software error.

    But just before 4 a.m. Eastern time on Wednesday, December 18, CHEOPS finally took flight. Here’s what you need to know.

    CHEOPS is a focused study of known exoplanets

    Compared to exoplanet hunters like NASA’s TESS, and Kepler before it, a satellite currently scouring the skies for new bodies orbiting distant dwarf stars, CHEOPS’ mission is a little different. Rather than turning its lens to the unknown, this satellite plans to focus on some of the 4,000-plus exoplanets previous missions have already identified—and find out as much about them as it can.

    NASA/MIT TESS replaced Kepler in search for exoplanets

    NASA/Kepler Telescope, and K2 March 7, 2009 until November 15, 2018

    “Detecting exoplanets is now the norm,” Matt Griffin, an astronomer at Cardiff University in the United Kingdom, tells Jonathan O’Callaghan at Nature News. “But we need to move into a new era in which we start to characterize and measure their detailed properties.”

    To accomplish this, CHEOPS will observe nearby stars already known to host their own planets that fall between Earth and Neptune, the most mid-sized planets in our solar system, in diameter. Because these planets can’t be seen up close, the satellite will measure them indirectly, waiting for blips in the brightness of their stars—an indication that a planet has passed in front of them.

    One of the most important important measurements CHEOPS will home in on is the size of various exoplanets that astronomers have already made mass estimates for. Those two numbers combined give scientists enough information to calculate density, a critical metric that can hint at a planet’s composition. Researchers are expecting some targets to be rocky like Earth, while others might be gassy like Neptune, or perhaps rich in subsurface water.

    2
    The CHEOPS telescope being assembled and tested in the clean room at the University of Bern ( T. Beck / University of Bern)

    An unusual orbit for an unusual mission

    Launched on a Soyuz-Fregat rocket, CHEOPS will settle into orbit about 500 miles above Earth’s surface, circling the planet’s poles from north to south. To ensure maximal access to prime image-snapping conditions—that is, dark skies—the satellite will always keep its main instrument pointed toward the side of Earth experiencing night, or away from the sun.

    The $55-million spacecraft isn’t a big one, measuring just five feet on each side, a fraction of the size of the Hubble Space Telescope. But its plan is ambitious: From April 2020, onward, CHEOPS will study between 300 and 500 worlds in just three and a half years.

    CHEOPS sets the stage for future missions

    CHEOPS’ mission might sound cut and dry, but the measurements it takes could help scientists answer some lingering questions about the origin and evolution of planets around the galaxy. Knowing what lies at the heart of other small, rocky planets, for instance, could clue researchers in to the crucial ingredients that help them come together, explains Kate Isaak, a CHEOPS project scientist at the European Space Research and Technology Centre in the Netherlands, in an interview with O’Callaghan.

    The list of hundreds of planets CHEOPS turns its eye on will also be whittled down by the satellite’s observations, identifying the most promising candidates for future study.

    Though CHEOPS is the first “follow-up” space surveyor of exoplanets, it won’t be the last. The highly-anticipated James Webb Space Telescope, scheduled to launch in the early 2020s, will be one of several crafts joining the search.

    NASA/ESA/CSA Webb Telescope annotated

    The ESA will also deploy the PLAnetary Transits and Oscillations of stars (PLATO) and Atmospheric Remote-sensing Infrared Exoplanet Large-survey (ARIEL) missions in the late 2020s to further investigate new worlds, according to a statement.

    ESA PLATO spacecraft depiction

    UK-led ESA mission ARIEL -Atmospheric Remote-sensing Infrared Exoplanet Large-survey

    Together, the three probes will collect data on planets that exhibit potential glimmers of habitability—ones that orbit their stars at a distance conducive to the existence of liquid water, for instance, or harbor atmospheres that resemble our own.

    “We are very much looking forward … to [following] up on some of the known exoplanets in more detail,” Isaak said in a statement in July. The launch, she said, is just “the beginning of our scientific adventure.”

    See the full article here .

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  • richardmitnick 11:58 am on November 6, 2019 Permalink | Reply
    Tags: "Scientists Around the World Declare ‘Climate Emergency’", , , , More than 11000 signatories to a new research paper argue that we need new ways to measure the impacts of a changing climate on human society., Severe threat to humanity, Smithsonian.com, The new paper in "Bioscience"looks at 40 years of climate data.   

    From smithsonian.com: “Scientists Around the World Declare ‘Climate Emergency’” 

    smithsonian
    From smithsonian.com

    November 5, 2019
    Avery Thompson

    More than 11,000 signatories to a new research paper argue that we need new ways to measure the impacts of a changing climate on human society.

    1
    An image of the Camp Fire in Northern California on November 8, 2018, from the Landsat 8 satellite. (USGS / NASA / Joshua Stevens)

    NASA/Landsat 8

    The world’s scientists are increasingly worried about our civilization’s reluctance to tackle climate change, so in a paper released today, thousands of them are raising the alarm.

    In a report published in the journal BioScience, over 11,000 of the world’s leading climate scientists have added their names to a declaration calling the planet’s current warming trends a “climate emergency.” Titled “World Scientists’ Warning of a Climate Emergency,” the paper takes an urgent tone, detailing a dire situation that will require extreme responses to avert disaster.

    “As a scientist, I feel that I must speak out about climate change, since it is such a severe threat to humanity,” says Bill Ripple, an ecologist at Oregon State University and lead author of the new report. In addition to a warning about the future, Ripple, his co-authors and the 11,258 other people who attached their names to the paper suggest a set of tools to make sense of our changing world.

    2
    Flooding level shown against a speed limit sign in Finchfield, IA. (Don Becker, USGS)

    The paper, which looks at 40 years of climate data, argues that scientists as well as world leaders should start moving away from using a single number to track the progress of climate change: global average surface temperature. When the world’s leaders signed the Paris Agreement in 2015, that’s the number they used.

    According to the Paris Agreement, if the global average surface temperature rises more than 1.5 degrees Celsius, we’ll start seeing more extreme weather events and around two feet of sea level rise. If it rises more than 2 degrees, we’ll experience significant melting of the polar ice caps, widespread desertification and severe coastal flooding. If we do nothing at all about climate change, we could see 4 degrees or more of warming, which could trigger a so-called “hothouse Earth” [PNAS] scenario where runaway climate effects bring us past a point of no return, resulting in a world barely habitable for humans with major population losses around the globe.

    But, Ripple argues, global average surface temperature is too simple to capture the nuances of climate change. It ignores other pieces of crucial information, and it doesn’t address all the various ways our planet is transforming.

    “For the average policy maker or the public, 1.5 degrees centigrade does not sound like a catastrophe,” he says. “It seems like, ‘O.K., that would be a little warmer, but not too bad.’”

    But a global average increase of just a degree and a half would have nuanced and cascading effects. To address this variation, the researchers developed a suite of different metrics, including the amount of heat stored in the oceans, the masses of the polar ice caps, the economic losses sustained from extreme weather events, and the area of land covered by wildfires in the United States.

    3
    According to the graphs Ripple and his colleagues have put together, despite decades of work fighting climate change, human impact is only getting worse. Fossil fuel use is still increasing. CO2 emissions are barely slowing down. The world’s forests are shrinking as quickly as ever. (William J. Ripple et al. / BioScience)

    “The effects of climate change are much broader than just surface temperature,” Ripple says. By incorporating these additional metrics in the conversation, researchers hope to highlight the wide array of climate change’s affects and make them clearer to the public.

    “By setting our goals with a single set of measures, we were making the climate problem more abstract,” says David Victor, a climate researcher at the Scripps Institution of Oceanography and a professor of international relations at the University of California, San Diego. “It was hard to see the progress people were making with that indicator.”

    In 2015, Victor authored a paper [Nature Climate Change] arguing that the climate debate needed more diverse metrics. Four years later, along with a large body of additional research, this new paper outlines a different way of looking at climate change. Surface temperatures are just one indicator out of many, but regardless of what you focus on, the picture looks increasingly grim.

    Over the last decade, for example, the cost of hurricanes, fires, floods, droughts and other such disasters has nearly doubled. The world is projected to spend around $200 billion on climate-related disaster relief next year. That cost is only going to go up as the Earth gets warmer.

    4
    Climate change has many wide-reaching impacts beyond a rising thermometer. Effects include hotter and more acidic oceans, melting ice caps, rising sea levels and more extreme weather. (William J. Ripple et al. / BioScience)

    The research team also developed a second set of metrics to track humanity’s impact on worldwide climate. “We think that to be holistic in the conversation, and for considering transformative change by society, we should track how we’re behaving as humans,” Ripple says.

    Dozens of measurements are included, including acreage of deforestation, world GDP, rate of population growth, and even how many cows there are around the world. Collectively, they paint a picture of a society either unaware of the damage it’s doing or unwilling to change. Still, the information is going to come in handy as scientists and leaders seek out solutions.

    “You want to understand not just the impact, but also what are the levers you can pull in order to reduce that impact,” Victor says.

    The research lists six steps to avoid the worst of an oncoming climate disaster. These steps fall into broad categories, such as energy, short-lived pollutants, nature conservation, food, economy and population. They range from well-known solutions like transitioning away from fossil fuels and countering deforestation to more uncomfortable tactics like slowing population growth and eating less meat.

    “We’re suggesting a major transformative change in the way that society functions that would promise a greater future well-being for humans,” Ripple says. “I have hope that we will do what it takes to sustain life on planet Earth.”

    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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