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  • richardmitnick 9:48 am on December 31, 2018 Permalink | Reply
    Tags: , , , , New Horizons, NYT,   

    From The New York Times: “NASA’s New Horizons Will Visit Ultima Thule on New Year’s Day” 

    New York Times

    From The New York Times

    Dec. 31, 2018
    Kenneth Chang

    The probe that visited Pluto will study a mysterious icy world just after midnight. Ultima Thule will be the most distant object ever visited by a spacecraft.

    We should get a clearer look at the Kuiper Belt object, Ultima Thule, when the New Horizons spacecraft, which took this composite image between August and mid-December, flies by on Jan. 1. Credit NASA/Johns Hopkins Applied Physics Laboratory/Southwest Research Institute

    NASA’s New Horizons spacecraft, which flew past Pluto in 2015, will zip past another icy world nicknamed Ultima Thule on New Year’s Day, gathering information on what is believed to be a pristine fragment from the earliest days of the solar system.

    NASA New Horizons spacecraft

    It will be the most distant object ever visited by a spacecraft.

    At 12:33 a.m. Eastern time, New Horizons will pass within about 2,200 miles of Ultima Thule, speeding at 31,500 m.p.h.

    How do I watch the flyby?

    Though it is a NASA spacecraft, the New Horizons mission is operated by the Johns Hopkins Applied Physics Laboratory in Maryland. Coverage of the flyby will be broadcast on the lab’s website and YouTube channel as well as NASA TV. On Twitter, updates will appear on @NewHorizons2015, the account maintained by S. Alan Stern, the principal investigator for the mission, and on NASA’s @NASANewHorizons account.

    While the scientists will celebrate the moment of flyby as if it were New Year’s, they will have no idea how the mission is actually going at that point. The spacecraft, busy making its science observations, will not turn to send a message back to Earth until a few hours later. Then it will take six hours for that radio signal, traveling at the speed of light, to reach Earth.

    Tell me about this small frozen world

    Based on suggestions from the public, the New Horizons team chose a nickname for the world: Ultima Thule, which means “distant places beyond the known world.” Officially, it is 2014 MU69, a catalog designation assigned by the International Astronomical Union’s Minor Planet Center. The “2014” refers to the year it was discovered, the result of a careful scan of the night sky by the Hubble Space Telescope for targets that New Horizons might be able to fly by after its Pluto encounter.

    No telescope on Earth has been able to clearly spot MU69. Even sharp-eyed Hubble can make out only a dot of light. Scientists estimate that it is 12 to 22 miles wide, and that it is dark, reflecting about 10 percent of the light that hits it.

    Four billion miles from the sun, MU69 is a billion miles farther out than Pluto, part of the ring of icy worlds beyond Neptune known as the Kuiper belt. Its orbit, nearly circular, suggests that it has been undisturbed since the birth of the solar system 4.5 billion years ago.

    Why do planetary scientists care about this small thing 4 billion miles from the sun?

    Every time a spacecraft visits an asteroid or a comet, planetary scientists talk about how it is a precious time capsule from the solar system’s baby days when the planets were forming. That is true, but especially true for Ultima Thule.

    Asteroids around the solar system have collided with each other and broken apart. Comets partially vaporize each time they pass close to the sun. But Ultima Thule may have instead been in a deep freeze the whole time, perhaps essentially pristine since it formed 4.5 billion years ago.

    Will there be pictures of Ultima Thule?

    New Horizons has been taking pictures for months, but for most of that time Ultima Thule has been little more than a dot in any of these images.

    At a news conference on Tuesday morning after the flyby, the scientists expect to release a picture taken before the flyby. Ultima Thule is expected to be a mere six pixels wide in that picture — enough to get a rough idea of its shape but not much more.

    The first set of images captured by New Horizons during the flyby should be back on Earth by Tuesday evening, and those are to be shown at news conferences describing the science results on Wednesday and Thursday.

    But when the pictures come, they could be striking — in case you forgot what kind of pictures New Horizons took when it flew past Pluto, here are some highlights of its findings.

    Isn’t NASA closed?

    Yes, NASA is one of the agencies affected by the partial federal government shutdown, and most NASA employees are currently furloughed. However, missions in space, including New Horizons, are considered essential activities. (It would be a shame if NASA had to throw away spacecraft costing hundreds of millions of dollars.)

    NASA will not be issuing news releases, but the Johns Hopkins Applied Physics Laboratory public affairs staff will get the news out, and on Friday, NASA Administrator Jim Bridenstine indicated that the agency would continue providing information on New Horizons as well as Osiris-Rex, a mission that is exploring a near-earth asteroid, Bennu.

    NASA OSIRIS-REx Spacecraft

    What happens after the flyby?

    Because New Horizons is so far away, its radio signal is weak, and the data will trickle back over the next 20 months. At the same time, it will make observations of other objects in the Kuiper belt to compare with Ultima Thule.

    The spacecraft has enough propellant left to possibly head to a third target, but that depends on whether there is anything close enough along its path. Astronomers, busy with Ultima Thule, have yet to start that new search.

    Beyond that, New Horizons will continue heading out of the solar system. Powered by a plutonium power source, it will to take data and communicate home with Earth for perhaps another 20 years, headed out of the solar system. However, it is not moving quite as fast as the Voyager 1 and Voyager 2 spacecraft that have now both entered interstellar space, so it is unclear whether New Horizons will make a similar crossing before its power runs out.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 11:06 am on December 25, 2018 Permalink | Reply
    Tags: , , , , , NYT, , ,   

    From The New York Times: “It’s Intermission for the Large Hadron Collider” 

    New York Times

    From The New York Times

    This is a special Augmented reality production of the NYT. Please view the original full article to take advantage of the 360 degree images inside the LHC.

    DEC. 21, 2018
    Dennis Overbye

    The largest machine ever built is shutting down for two years of upgrades. Take an immersive tour of the collider and study the remnants of a Higgs particle in augmented reality.


    CERN Control Center

    MEYRIN, Switzerland — There is silence on the subatomic firing range.

    A quarter-century ago, the physicists of CERN, the European Center for Nuclear Research, bet their careers and their political capital on the biggest and most expensive science experiment ever built, the Large Hadron Collider.


    CERN map

    CERN LHC Tunnel

    CERN LHC particles




    CERN/ALICE Detector

    CERN CMS New

    CERN LHCb New II

    The collider is a kind of microscope that works by flinging subatomic particles around a 17-mile electromagnetic racetrack beneath the French-Swiss countryside, smashing them together 600 million times a second and sifting through the debris for new particles and forces of nature. The instrument is also a time machine, providing a glimpse of the physics that prevailed in the early moments of the universe and laid the foundation for the cosmos as we see it today.

    The reward came in 2012 with the discovery of the Higgs boson, a long-sought particle that helps explain why there is mass, diversity and life in the cosmos.

    CERN CMS Higgs Event

    CERN ATLAS Higgs Event

    The discovery was celebrated with champagne and a Nobel prize.

    The collider will continue smashing particles and expectations for another 20 years. But first, an intermission. On December 3rd, the particle beams stopped humming. The giant magnets that guide the whizzing protons sighed and released their grip. The underground detectors that ring the tunnel stood down from their watch.

    Over the next two years, during the first of what will be a series of shutdowns, engineers will upgrade the collider to make its beams more intense and its instruments more sensitive and discerning. And theoretical physicists will pause to make sense of the tantalizing, bewildering mysteries that the Large Hadron Collider has generated so far.

    When protons collide

    The collider gets its mojo from Einstein’s dictum that mass and energy are the same. The more energy that the collider can produce, the more massive are the particles created by the collisions. With every increase in the energy of their collider, CERN physicists are able to edge farther and farther back in time, closer to the physics of the Big Bang, when the universe was much hotter than today.

    Inside CERN’s subterranean ring, some 10,000 superconducting electromagnets, powered by a small city’s worth of electricity, guide two beams of protons in opposite directions around the tunnel at 99.99999 percent of the speed of light, or an energy of 7 trillion electron volts. Those protons make the 17-mile circuit 11,000 times a second. (In physics, mass and energy are both expressed in terms of units called electron volts. A single proton, the building block of ordinary atoms, weighs about a billion electron volts.)

    The protons enter the collider as atoms in a puff of hydrogen gas squirted from a bottle. As the atoms travel, electrical fields strip them of electrons, leaving bare, positively charged protons. These are sped up by a series of increasingly larger and more energetic electromagnets, until they are ready to enter the main ring of the collider.

    When protons finally enter the main ring, they have been boosted into flying bombs of primordial energy, primed to smash apart — and recombine — when they strike their opposite numbers head-on, coming from the other direction.

    The protons circulate inside vacuum pipes – one running clockwise, the other counterclockwise – and these are surrounded by superconducting electromagnets strung together around the tunnel like sausages. To generate enough force to bend the speeding protons, the magnets must be uncommonly strong: 8.3 Tesla, or more than a hundred thousand times stronger than Earth’s magnetic field — and more than strong enough to wreck a fancy Swiss watch.

    Such a field in turn requires an electrical current of 12,000 amperes. That’s only feasible if the magnets are superconducting, meaning that electricity flows without expensive resistance. For that to happen, the magnets must be supercold; they are bathed in 150 tons of superfluid helium at a temperature of 1.9 Kelvin, making the Large Hadron Collider literally one of the coldest places in the universe.

    If things go wrong down here, they can go very wrong. In 2008, as the collider was still being tuned up, the link between a pair of magnets exploded, delaying operations for almost two years.

    The energy stored in the magnetic fields is equivalent to a fully loaded jumbo jet going 500 miles per hour; if a magnet loses its cool and heats up, all that energy must go someplace. And the proton beam itself can cut through many feet of steel.

    A tale of four detectors

    The beams cross at four points around the racetrack.

    At each juncture, gigantic detectors — underground mountains of electronics, cables, computers, pipes, magnets and even more magnets — have been erected. The two biggest and most expensive experiments, CMS (the Compact Muon Solenoid) and Atlas (A Toroidal L.H.C. Apparatus) sit, respectively, at the noon and 6 o’clock positions of the circular track.

    Wrapped around them, like the layers of an onion, are instruments designed to measure every last spark of energy or matter that might spew from the collision. Silicon detectors track the paths of lightweight, charged particles such as electrons. Scintillation crystals capture the energies of gamma rays. Chambers of electrified gas track more far-flung particles. And powerful magnets bend the paths of these particles so that their charges and masses can be determined.

    The proton beams cross 40 million times per second in each of the four detectors, resulting in about a billion actual collisions every second.

    What’s the antimatter?

    Why is there something instead of nothing in the universe?

    Answering that question is the mission of the detector known as LHCb, which sits at about 4 o’clock on the collider dial. The “b” stands for beauty — and for the B meson, a subatomic particle that is crucial to the experiment.

    When matter is created — in a collider, in the Big Bang — equal amounts of matter and its opposite, antimatter, should be formed, according to the laws of physics As We Know Them. When matter and antimatter meet, they annihilate each other, producing energy.

    By that logic, when matter and antimatter formed in the Big Bang, they should have cancelled out each other, leaving behind an empty universe. But it’s not empty: We are here, and our antimatter is not.

    Why not? Physicists suspect that some subtle imbalance between matter and antimatter is responsible. The LHCb experiment looks for that imbalance in the behavior of B mesons, which are often sprayed from the proton collisions.

    B mesons have an exotic property: They flicker back and forth between being matter and antimatter. Sensors record their passage through the LHCb room, seeking differences between the particles and their antimatter twins. Any discrepancy between the two could be a clue to why matter flourished billions of years ago and antimatter perished.

    Turning back the cosmic clock

    At about 8 o’clock on the collider dial is Alice, another detector with a special purpose. It, too, is fixed on the distant past: the brief moment a couple of microseconds after the Big Bang, before the first protons and neutrons congealed out of a “primordial soup” of quarks and gluons.

    Alice’s job is to study tiny droplets of that distant past that are created when the collider bangs together lead ions instead of protons. Researchers expected this material, known in the lingo as a quark-gluon plasma, to behave like a gas, but it turns out to behave more like a liquid.

    Sifting the data

    The collider’s enormous detectors are like 100 megapixel cameras that take 40 million pictures a second. Most of the data from that deluge is immediately thrown away. Triggers, programmed to pick out events that physicists thought might be interesting, save only about a thousand collision events per second. Even still, an enormous pool of data winds up in the CERN computer banks.

    CERN DATA Center

    According to the casino rules of modern quantum physics, anything that can happen will happen eventually. Before a single proton is fired through the collider, computers have calculated all the possible outcomes of a collision according to known physics. Any unexpected bump in the real data at some energy could be a signal of unknown physics, a new particle.

    That was how the Higgs was discovered, emerging from the statistical noise in the autumn of 2011. Only one of every 10 billion collisions creates a Higgs boson. The Higgs vanishes instantly and can’t be observed directly, but it decays into fragments that can be measured and identified.

    What eventually stood out from the data was evidence for a particle that weighs all by itself as much as an iodine atom: a flake of an invisible force field that permeates space like molasses, impeding motion and assigning mass to objects that pass through it.

    And so in 2012, after half a century and billions of dollars, thousands of physicists toasted over champagne. Peter Higgs, for whom the elusive boson was named, shared the Nobel prize with François Englert, who had independently predicted the particle’s existence.

    Peter Higgs

    François Englert

    An intermission underground

    The current shutdown is the first of a pair of billion-dollar upgrades intended to boost the productivity of the Large Hadron Collider tenfold by the end of the decade.

    The first shutdown will last for two years, until 2021; during that time, engineers will improve the series of smaller racetracks that speed up protons and inject them into the main collider. The collider then will run for two years and shut down again, in 2024, for two more years, so that engineers can install new magnets to intensify the proton beams and collisions.

    Reincarnated in 2026 as the High Luminosity L.H.C., the collider is scheduled to run for another decade, until 2035 or so, which means its career probing the edge of human knowledge is still beginning.

    Judging by the collider’s productivity, measured in terms of trillions of subatomic smashups, more than 95 percent of its scientific potential lies ahead.

    Both the Atlas and CMS experiments will receive major upgrades during the next two shutdowns, including new silicon trackers, to replace the olds ones burned out by radiation.

    To keep up with the increased collision rate, both Atlas and CMS have had to upgrade the finicky trigger systems that decide which collision events to keep and study. Currently, of a billion events per second, they can keep 1,500; the upgrade will raise that figure to 10,000.

    And what a flow of collisions it will be. Physicists measure the productivity, or luminosity, of their colliders in terms of collisions. It took about 3,000 trillion collisions to confirm the Higgs boson. As of the December shutdown the collider had logged about 20,000 trillion collisions. But those were, and are, early days.

    By 2037, the Large Hadron Collider should have produced roughly 4 million trillion primordial fireballs, bristling with who knows what. The whole universe is still up for grabs.

    After the Higgs

    Discovering the Higgs was an auspicious start. But the champagne came with a mystery.

    Over the last century, physicists have learned to explain some of the grandest and subtlest phenomena in nature — the arc of a rainbow, the scent of a gardenia, the twitch of a cat’s whiskers — as a handful of elementary particles interacting through four basic forces, playing a game of catch with force-carrying particles called bosons according to a set of equations called the Standard Model.

    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.

    But why these particles and these forces? Why is the universe made of matter but not antimatter? What happens at the center of a black hole, or happened at the first instant of the Big Bang? If the Higgs boson determines the masses of particles, what determines the mass of the Higgs?

    Who, in other words, watches the watchman?

    The Standard Model, for all its brilliance and elegance, does not say. Particles that might answer these questions have not shown up yet in the collider. Fabiola Gianotti, the director-general of CERN, expressed surprise. “I would have expected new physics to manifest itself at the energy scale of the Large Hadron Collider,” she said.

    Some physicists have responded by speculating about multiple universes and other exotic phenomena. Some clues, Dr. Gianotti said, might come from studying the new particle on the block, the Higgs.

    “We physicists are happy when we understand things, but we are even happier when we don’t understand,” she said. “And today we know that we don’t understand everything. We know that we are missing something important and fundamental. And this is very exciting.”

    Colliders of tomorrow

    Humans soon must decide which machines, if any, will be built to augment or replace the Large Hadron Collider. That collider had a “killer app” of sorts: it was designed to achieve an energy at which, according to the prediction of the Standard Model, the Higgs or something like it would become evident and provide an explanation for particle masses.

    But the Standard Model doesn’t predict a new keystone particle in the next higher energy range. Luckily, nobody believes the Standard Model is the last word about the universe, but as the machines increase in energy, particle physicists will be shooting in the dark.

    For a long time, the leading candidate for Next Big Physics Machine has been the International Linear Collider, which would fire electrons and their antimatter opposites, positrons, at each other.

    ILC schematic, being planned for the Kitakami highland, in the Iwate prefecture of northern Japan

    The collisions would produce showers of Higgs bosons. The experiment would be built in Japan, if it is built at all, but Japan has yet to commit to hosting the project, which would require them to pay for about half of the $5.5 billion cost- see https://sciencesprings.wordpress.com/2018/12/21/from-nature-via-ilc-plans-for-worlds-next-major-particle-collider-dealt-big-blow.

    In the meantime, Europe has convened meetings and workshops to decide on a plan for the future of particle physics there. “If there is no word from Japan by the end of the year, then the I.L.C. will not figure in the next five-year plan for Europe,” Lyn Evans, a CERN physicist who was in charge of building the Large Hadron Collider, said in an email.

    CERN has proposed its own version of a linear collider, the Compact Linear Collider, that could be scaled up gradually from Higgs bosons to higher energies. Also being considered is a humongous collider, 100 kilometers around, that would lie under Lake Geneva and would reach energies of 100 trillion electron volts — seven times the power of the Large Hadron Collider.

    Cern Compact Linear Collider

    CLC map


    And in November the Chinese Academy of Sciences released the design for a next-generation collider of similar size, called the Circular Electron Positron Collider.

    China Circular Electron Positron Collider (CEPC) map

    China Circular Electron-Positron collider depiction

    The machine could be the precursor for a still more powerful machine that has been dubbed the Great Collider. Politics and economics, as well as physics, will decide which, if any, of these machines will see a shovel.

    “If we want a new machine, nothing is possible before 2035,” Frederick Bordry, CERN’s director of accelerators, said of European plans. Building such a machine is a true human adventure, he said: “Twenty-five years to build and another 25 to operate.”

    Noting that he himself is 64, he added, “I’m working for the young people.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 11:52 am on December 18, 2018 Permalink | Reply
    Tags: , Continental drift, , Hard evidence of tectonic origins was destroyed long ago, NYT, , The link between plate tectonics and the evolution of complex life, What caused the shell to crack apart in the first place, With subduction established water like oceanic crust, would cycle between Earth’s surface and mantle, You need plate tectonics to sustain life   

    From The New York Times: “The Earth’s Shell Has Cracked, and We’re Drifting on the Pieces” 

    New York Times

    From The New York Times

    Dec. 18, 2018
    Natalie Angier

    Plate tectonics helped make our planet stable and habitable. But the slow shifting of continents is still a mysterious process.

    The San Andreas fault in the Carrizo Plain in California. The fault line forms the boundary between the Pacific and the North American plates. Credit Peter Menzel/Science Source

    The theory of plate tectonics is one of the great scientific advances of our age, right up there with Darwin’s theory of evolution and Einstein’s theory of relativity.

    The idea that Earth’s outer shell is broken up into giant puzzle pieces, or plates, all gliding atop a kind of conveyor belt of hot, weak rock — here rising up from the underlying mantle, there plunging back into it — explains much about the structure and behavior of our home planet: the mountains and ocean canyons, the earthquakes and volcanoes, the very composition of the air we breathe.

    Yet success is no guarantee against a midlife crisis, and so it is that half a century after the basic mechanisms of plate tectonics were first elucidated, geologists are confronting surprising gaps in their understanding of a concept that is truly the bedrock of their profession.

    They are sparring over when, exactly, the whole movable plate system began. Is it nearly as ancient as the planet itself — that is, roughly 4.5 billion years old — or a youthful one billion years, or somewhere in between?

    They are asking what caused the shell to crack apart in the first place, and how the industrious recycling of Earth’s crust began.

    They are comparing Earth with its sister planet, Venus. The two worlds are roughly the same size and built of similar rocky material, yet Earth has plate tectonics and Venus does not. Scientists want to know why.

    “In the 1960s and 70s, when people came up with the notion of plate tectonics, they didn’t think about what it was like in the distant past,” said Jun Korenaga, a geophysicist at Yale University.

    “People were so busy trying to prove plate tectonics by looking at the present situation, or were caught up applying the concept to problems in their own field. The origin issue is a much more recent debate.”

    Researchers also are exploring the link between plate tectonics and the evolution of complex life. Fortuitously timed continental collisions and mountain smackdowns may well have supplied crucial nutrients at key moments of biological inventiveness, like the legendary Cambrian explosion of 500 million years ago, when the ancestors of modern life-forms appeared.

    “The connection between deep Earth processes and Earth surface biology hasn’t been thought about too clearly in the past, but that’s changing fast,” said Aubrey Zerkle, a geochemist at the University of St. Andrews in Scotland.

    It’s increasingly obvious that “you need plate tectonics to sustain life,” Dr. Zerkle added. “If there wasn’t a way of recycling material between mantle and crust, all these elements that are crucial to life, like carbon, nitrogen, phosphorus and oxygen, would get tied up in rocks and stay there.”

    The origin and implications of plate tectonics were the subject of a recent meeting and themed issue of Philosophical Transactions of the Royal Society.

    Researchers said that pinning down when and how Earth’s vivid geological machinations arose will do more than flesh out our understanding of our home base. The answers could well guide our search for life and habitable planets beyond the solar system.

    Robert Stern, a geoscientist at the University of Texas at Dallas, argues that if we’re looking for another planet to colonize, we want to avoid ones with signs of plate tectonic activity. Those are the places where life is likely to have evolved beyond the “single cell or worm stage, and we don’t want to fight another technological civilization for their planet.”

    “A relatively benign way for the Earth to lose heat”

    Mount Singabung erupting in Indonesia in October 2014. Plate tectonics “allows Earth to maintain a stabler and more benign environment overall,” explained one scientist. Credit Dedy Sahputra/European Pressphoto Agency

    The idea that continents are not fixed but rather peregrinate around the globe dates back several centuries, when mapmakers began noticing the complementarity of various land masses — for example, the way the northeast bulge of South America looks as though it could fit snugly in the cupped palm of the southwest coast of Africa.

    But it wasn’t until the mid-twentieth century that the generic notion of “continental drift” was transformed into a full-bodied theory, complete with evidence of a subterranean engine driving these continental odysseys.

    Geologists determined that Earth’s outer layer is broken into eight or nine large segments and five or six smaller ones, a mix of relatively thin, dense oceanic plates riding low and thicker, lighter continental plates bobbing high.

    At large fissures on the ocean floor, melting rock from the underlying mantle rises up, adding to the oceanic plates. At other fracture points in the crust, oceanic plates are diving back inside, or subducting, their mass devoured in the mantle’s hot belly.

    The high-riding continental plates are likewise jostled by the magmatic activity below, skating around at an average pace of one or two inches a year, sometimes crashing together to form, say, the Himalayan mountain chain, or pulling apart at Africa’s Great Rift Valley.

    All this convective bubbling up and recycling between crust and mantle, this creative destruction and reconstruction of parts — “tectonic” comes from the Greek word for build — is Earth’s way of following the second law of thermodynamics. The movement shakes off into the frigidity of space the vast internal heat that the planet has stored since its violent formation.

    And while shifting, crumbling plates may seem inherently unreliable, a poor foundation on which to raise a family, the end result is a surprising degree of stability. “Plate tectonics is a relatively benign way for Earth to lose heat,” said Peter Cawood, an Earth scientist at Monash University in Australia.

    “You get what are catastrophic events in localized areas, in earthquakes and tsunamis,” he added. “But the mechanism allows Earth to maintain a stabler and more benign environment overall.”

    Sulfuric gas in the Afar Triple Junction in Ethiopia, at the top of the Great Rift Valley. Three tectonic plates meet at this spot: the Arabian plate and two African plates, Nubian and Somali. Credit Massimo Rumi/Barcroft Media, via Getty Images

    Unfortunately for geologists, the very nature of plate tectonics obscures its biography. Oceanic crust, where the telltale mantle exchange zones are located, is recycled through the upwelling and subducting pipeline every 200 million years or so, which means hard evidence of tectonic origins was destroyed long ago.

    Continental crust is older, and rocks dating back more than 4 billion years have been identified in places like Jack Hills, Australia. But continental plates float above the subductive fray, revealing little of the system’s origins.

    Nevertheless, geoscientists are doing their best with extant rocks, models and laboratory experiments to sketch out possible tectonic timelines. Dr. Korenaga and his colleagues have proposed that plate tectonics began very early, right after Earth’s crust solidified from its initial magmatic state.

    “That is when the conditions would have been easiest for plate tectonics to get started,” he said. At that point, he said, most of the water on Earth — delivered by comets — would still be on the surface, with little of it having found its way into the mantle. The heat convecting up through the mantle would exert a stronger force on dry rocks than on rocks that were lubricated.

    At the same time, the surface water would make it easier for the hot, twisting rocks beneath to crack the surface lid apart, rather as a sprinkling of water from the faucet eases the task of popping ice cubes from a tray. The cracking open of the surface lid, Dr. Korenaga said, is key to getting the all-mighty subduction engine started. With subduction established, water, like oceanic crust, would cycle between Earth’s surface and mantle.

    Water is constantly recycled between the mantle and crust

    A map of tectonic plates in the Indian Ocean based on data showing seafloor gravity anomalies. The red areas show areas where gravity is stronger, largely aligning with underwater ridges, seamounts and plate edges. Credit Joshua Stevens, Sandwell, D. et al., NASA

    On the opposite end of the origins debate is Dr. Stern, who argues that plate tectonics is a mere billion years old or less, and that Earth spent its first 3.5 billion years with a simple “single lid” as its outer shell: a crust riddled with volcanoes and other means of heat ventilation, but no moving plates, no subduction, no recycling between inside and out.

    As evidence of the youthfulness of the plate regimen, Dr. Stern points to two classes of rocks: ophiolites and blueschist.

    Ophiolites are pieces of oceanic crust atop bits of underlying mantle that have made their way onto land and thus have escaped the relentless recycling of oceanic crust. Recent research has shown that ophiolites are not just any slice of oceanic crust, Dr. Stern said, but rather were formed by the forces of subduction.

    Similarly, blueschists are rocks that are fashioned under very high pressure but low temperatures, and “the only place you can do that is in a subduction zone,” Dr. Stern said.

    Nearly all ophiolites are less than a billion years old, he added, while the most ancient blueschists, found in China, are just 800 million years old. No ophiolites, no blueschists, no evidence of subduction or plate tectonics.

    Most geologists opt for a middle ground. “Science is a democratic process,” said Michael Brown, a geologist at the University of Maryland and an editor of the themed issue, “and the prevailing view is that Earth started to exhibit behaviors that look like plate tectonics 2.5 to 3 billion years ago.”

    Significantly, that chronology decouples plate tectonics from the origin of life on Earth: evidence of the earliest single-celled organisms dates back more than 3.6 billion years. Nevertheless, scientists view plate tectonics as vital to the sustained evolution of that primordial life.

    In Iceland, a visible fault between the North American and Eurasian plates, which are pulling away from each other at a rate of about an inch a year. Credit Universal History Archive/UIG, via Getty Images

    Plate tectonic activity did not just help to stabilize Earth’s heat management system. The movement kept a steady supply of water shuttling between mantle and crust, rather than gradually evaporating from the surface.

    It blocked the dangerous buildup of greenhouse gases in the atmosphere by sucking excess carbon from the ocean and subducting it underground. It shook up mountains and pulverized rocks, freeing up essential minerals and nutrients like phosphorus, oxygen and nitrogen for use in the growing carnival of life.

    Dr. Zerkle discerns a link between geological and biological high drama: “It’s been suggested that time periods of supercontinental cycles — when small continents smash together to make large supercontinents, and those supercontinents then rip apart into smaller continents again — could have put large pulses of nutrients into the biosphere and allowed organisms to really take off.”

    Plate tectonics also built the right playing fields for Darwinian games.

    “Think about what drives evolution,” Dr. Stern said. “It’s isolation and competition. You need to break continents and continental shelves apart, and separate one ocean from another, for speciation to occur.”

    Life is always falling apart, on the rocks — and a good thing, too.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 5:29 pm on December 8, 2018 Permalink | Reply
    Tags: China’s Chang’e-4 Launches on Mission to the Moon’s Far Side, NYT   

    From The New York Times: “China’s Chang’e-4 Launches on Mission to the Moon’s Far Side” 

    New York Times

    From The New York Times

    Dec. 7, 2018
    Kenneth Chang

    China hopes to send its Chang’e-4 lunar lander to the far side of the moon, shown here illuminated by the sun in an image captured by NASA’s Deep Space Climate Observatory satellite. Credit NASA Goddard

    China is aiming to go where no one has gone before: the far side of the moon.

    A rocket carrying the Chang’e-4 lunar lander blasted off at about 2:23 a.m. local time on Saturday from Xichang Satellite Launch Center in southern China. (In the United States, it was still midday Friday). Chinese authorities did not broadcast the launch, but an unofficial live stream recorded near the site showed the rocket rise from the launchpad until its flames looked like a bright star in the area’s dark skies.

    Nearly one hour later, Xinhua, China’s state-run news agency reported that Chang’e-4 had successfully launched.

    Agence France-Presse-Getty Images

    Exactly when it will set down at its destination has not yet been announced — possibly in early January — but Chang’e-4 will provide the first close-up look at a part of the moon that is eternally out of view from Earth.

    What is Chang’e-4?


    Chang’e-4 includes two main parts: the main lander weighing about 2,400 pounds and a 300-pound rover. By comparison, NASA’s Opportunity rover on Mars weighs about 400 pounds, and the Curiosity rover there is much bigger, at 2,000 pounds.

    The spacecraft is largely a clone of Chang’e-3, which landed on the moon in 2013. Indeed, Chang’e-4 was built as the backup in case the first attempt failed. With the success — the first soft landing of any spacecraft on the moon since 1976 — the Chinese outfitted Chang’e-4 with a different set of instruments and decided to send it to a different location.

    Where is Chang’e-4 going?

    The rover will land in the 110-mile-wide Von Kármán crater. It is on the far side of the moon, which is always facing away from Earth. (The moon is what planetary scientists call “tidally locked” to the rotation of the Earth. That is, its period of rotation — its day — is the same as the time it takes to make one orbit around Earth.)

    The crater is within an area known as the South Pole-Aitken basin, a gigantic, 1,600-mile-wide crater at the bottom of the moon, which has a mineralogy distinct from other locations. That may reflect materials from the inside of the moon that were brought up by the impact that created the basin.

    The far side is also considerably more mountainous than the near side for reasons not yet understood.

    What will Chang’e-4 study?

    The suite of instruments on the rover and the lander include cameras, ground-penetrating radar and spectrometers to help identify the composition of rocks and dirt in the area. And China’s space agency has collaborated with other countries. One instrument was developed at Kiel University in Germany; another was provided by the Swedish Institute of Space Physics.

    The instruments will probe the structure of the rocks beneath the spacecraft and study the effects of the solar wind striking the lunar surface. Chang’e-4 will also test the ability of making radio astronomy observations from the far side of the moon, without the effects of noise and interference from Earth.

    According to the Xinhua news agency, Chang’e-4 is also carrying an intriguing biology experiment to see if plant seeds will germinate and silkworm eggs will hatch in the moon’s low gravity.

    China launched a relay satellite named Queqiao, which will beam messages between Earth and the Chang’e-4 lander, in May. Credit Cai Yang/XinHua, via Associated Press

    How will the spacecraft communicate with Earth?

    Because the moon blocks radio signals from our planet, the Chinese launched a satellite, called Queqiao, in May.

    Flying high: The Queqiao satellite will communicate between Earth and a lander that will be places on the far side of the Moon later this year (Courtesy: China Aerospace Science and Technology Corporation)

    It is circling high over the far side of the moon, and will relay messages between Earth and the Chang’e-4 lander.

    When will Chang’e-4 land on the moon?

    China’s space agency has not announced a landing date, though some expect that will be the first week of January, when the sun will be shining over the far side of the moon, an important consideration because Chang’e-4 is solar-powered.

    Zhang Xiaoping, an associate professor from Space Science Institute/Lunar and Planetary Science Laboratory of Macau University of Science and Technology, said that the spacecraft would follow the Chang’e-3’s trajectory. That means it would arrive in three to five days and then orbit the moon for several days (13 in the case of Chang’e-3) while preparing for the landing, he said.

    Wait, I thought the far side of the moon was dark.

    The far side is not dark all of the time.

    The first new moon of 2019 is Jan. 6. That’s when you cannot see the moon because the dark side — the side that is in shadow facing away from the sun — is facing Earth. And when the near side of the moon is dark, the far side is awash in bright sunshine.

    Why is China so secretive about all of this?

    Chinese officials have talked about Chang’e-4 in public, but their interactions with journalists more resemble the carefully managed strategy used by the Soviet program during the Cold War rather than the more open publicity by NASA and many other space agencies. That way, the Chinese, like the Soviets, could boast about the successes and downplay any failures.

    What does Chang’e mean?

    In Chinese mythology, Chang’e is the goddess of the moon. Other missions have been named after her, too.

    Chang’e-1 and 2 went into orbit around the moon but did not land. Chang’e-1 was launched in 2007. Chang’e-2 followed in 2010.

    The next step in China’s moon program is for the Chang’e-5 robotic spacecraft to land on the moon and then bring rock samples back to Earth for additional study.

    Chang’e-5 was supposed to head to the moon before Chang’e-4, but a launch failure of the large Chinese rocket needed to carry it to space delayed the mission until at least 2019.

    Who else is planning to go to the moon?

    Next year, the Indian government is planning to launch a mission, Chandrayaan-2, that includes an orbiter, a lander and a rover.

    The Indian Space Research Organisation (ISRO) is set to make yet another breakthrough in it series of space missions, with the launch of Chandrayaan-2,10 years after its first lunar mission in November 2008.

    SpaceIL, an Israeli team that was a finalist in the Google Lunar X Prize, is also still aiming to send a robotic lander to the moon early next year, even though the $20 million prize has expired.

    NASA announced last week that nine companies will compete for robotic missions to carry science experiments to the moon. The space agency said the first of those could go as early as 2019, but most of the companies said they would not be ready until 2021.

    Jim Bridenstine, the NASA administrator, has praised the Chang’e-4 mission as exciting, and at the International Astronautical Congress in Bremen, Germany in October, talked of possible collaboration with the Chinese space agency. Federal laws limit any NASA interaction with the Chinese.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 8:30 am on November 27, 2018 Permalink | Reply
    Tags: , , NYT, Yellowstone's Eternal Scenes are Changing Before Our Eyes   

    From The New York Times: “Your Children’s Yellowstone Will Be Radically Different” 

    New York Times

    From The New York Times

    NOV. 15, 2018
    Marguerite Holloway
    Photographs and time-lapse video by Josh Haner

    On a recent fall afternoon in the Lamar Valley, visitors watched a wolf pack lope along a thinly forested riverbank, ten or so black and gray figures shadowy against the snow. A little farther along the road, a herd of bison swung their great heads as they rooted for food in the sagebrush steppe, their deep rumbles clear in the quiet, cold air.

    In the United States, Yellowstone National Park is the only place bison and wolves can be seen in great numbers. Because of the park, these animals survive. Yellowstone was crucial to bringing back bison, reintroducing gray wolves, and restoring trumpeter swans, elk, and grizzly bears — all five species driven toward extinction found refuge here.

    Bison in Yellowstone.

    But the Yellowstone of charismatic megafauna and of stunning geysers that four million visitors a year travel to see is changing before the eyes of those who know it best. Researchers who have spent years studying, managing, and exploring its roughly 3,400 square miles say that soon the landscape may look dramatically different.

    Over the next few decades of climate change, the country’s first national park will quite likely see increased fire, less forest, expanding grasslands, shallower, warmer waterways, and more invasive plants — all of which may alter how, and how many, animals move through the landscape. Ecosystems are always in flux, but climate change is transforming habitats so quickly that many plants and animals may not be able to adapt well or at all.

    Yellowstone National Park, established in 1872, is one of the Unesco World Heritage sites threatened by climate change. It is home to some of the country’s oldest weather stations, including one at Mammoth Hot Springs. Data from the park and surrounding area has helped scientists understand and track climate change in the Western United States.

    Since 1948, the average annual temperature in the Greater Yellowstone Ecosystem — an area of 34,375 square miles that includes the park, national forests, and Grand Teton National Park — has risen about 2 degrees Fahrenheit. Researchers report that winter is, on balance, 10 days shorter and less cold.

    The Grand Prismatic Spring from above

    “For the Northern Rockies, snowpack has fallen to its lowest level in eight centuries,” said Patrick Gonzalez, a forest and climate change scientist at the University of California, Berkeley.

    Because snow is a cornerstone of the park’s ecology, the decline is alarming to some ecologists.

    The Grand Prismatic Spring.

    Summers in the park have become warmer, drier and increasingly prone to fire. Even if rainfall increases in the future, it will evaporate more quickly, said Michael Tercek, an ecologist who has worked in Yellowstone for 28 years.

    “By the time my daughter is an old woman, the climate will be as different for her as the last ice age seems to us,” Dr. Tercek said.

    Yellowstone’s unusual landscape — of snow and steam, of cold streams and hot springs — is volcanic. Magma gives rise to boiling water and multihued thermophiles, bacteria that thrive at high temperatures.

    In 1883, The New York Times described the park as an “almost mystical wonderland.”

    For many visitors, Yellowstone represents American wilderness: a place with big, open skies where antelope and bison still roam.

    “You run into visitors and they thank you for the place,” said Ann Rodman, a park scientist. “They are seeing elk and antelope for the first time in their lives.”

    An elk at Mammoth Hot Springs

    Ms. Rodman, who has been working in Yellowstone for 30 years, has pored over temperature and weather data. The trends surprised her, as well as the urgency.

    “When I first started doing it, I really thought climate change was something that was going to happen to us in the future,” she said. “But it is one of those things where the more you study it, the more you realize how much is changing and how fast.”

    “Then you begin to go through this stage, I don’t know if it is like the stages of grief,” Ms. Rodman said. “All of a sudden it hits you that this is a really, really big deal and we aren’t really talking about it and we aren’t really thinking about it.”

    Ann Rodman, a scientist at Yellowstone.

    Ms. Rodman has seen vast changes near the town of Gardiner, Mont., at the north entrance to Yellowstone. Some non-nutritious invasive plants like cheatgrass and desert madwort have replaced nutritious native plants. Those changes worry Ms. Rodman and others: Give invasives an inch and they take miles.

    Cheatgrass has already spread into the Lamar Valley. “This is what we don’t want — to turn into what it looks like in Gardiner,” Ms. Rodman said. “The seeds come in on people’s cars and on people’s boots.”

    Pronghorn antelope, with cheatgrass in the background.

    Cheatgrass can thrive in disturbed soils and can ignite “like tissue paper,” she said. It takes hold after fires, preventing native plants from regrowing.

    If cheatgrass and its ilk spread, bison and elk could be affected. Cheatgrass, for instance, grows quickly in the spring. “It can suck the moisture out of the ground early,” Ms. Rodman said. “Then it is gone, so it doesn’t sustain animals throughout the summer the way native grasses would.”

    In recent years, elk have lost forage when drier, hotter summers have shortened what ecologists call the green wave, in which plants become green at different times at different elevations, said Andrew J. Hansen of Montana State University.

    Some elk now stay in valleys outside the park, nibbling lawns and alfalfa fields, Dr. Hansen said. And where they go, wolves follow. “It is a very interesting mix of land-use change and climate change, possibly leading to quite dramatic shifts in migration and to thousands of elk on private land,” he said.

    Drier summers also mean that fires are a greater threat. The conditions that gave rise to the fires of 1988, when a third of the park burned, could become common.

    By the end of the century, “the weather like the summer of ’88 will likely be there all the time rather than being the very rare exception,” said Monica G. Turner of the University of Wisconsin-Madison. “As the climate is warming, we are getting fires that are happening more often. We are starting to have the young forests burn again before they have had a chance to recover.”

    Evergreen forest damaged by bark beetles.

    rees, and new growth, after a forest fire.

    In 2016, a wildfire swept through trees in a section near the Madison River that had burned in 1988. Because young trees don’t have many cones on them, Dr. Turner said, they don’t have as many seeds to release to form new forest. The cones they do have are close to the ground, which means they are less likely to survive the heat.

    Repeated fires could lead to more grassland. “The structure of the forests is going to change,” Dr. Turner said. “They might become sparse or not recover if we keep doing a double and triple whammy.”

    Forests shade waterways, and those too are experiencing climate-related changes. “We can very definitely see warming trends during the summer and fall,” said Daniel J. Isaak of the United States Forest Service. “Stream and river flows are declining as snowpack declines.” As fish become concentrated in smaller areas, Dr. Isaak said, disease can increase in a population because transmission is easier.

    Sour Creek

    In 2016, the Yellowstone River — famous for its fly fishing and its cutthroat trout, which thrive in colder waters — was closed to anglers for 183 miles downstream from the park after an outbreak of kidney disease killed thousands of fish. “The feeling was that this was a canary in the coal mine,” said Dan Vermillion of Sweetwater Travel Company, a fly-fishing operation in Livingston, Mont.

    Lower flows and warmer water are one consequence of spring arriving earlier. Quickly melting snow unleashing torrents is another. Flooding has affected the nesting of water birds like common loons, American white pelicans, and double-crested cormorants. “All their nesting is on lakes and ponds, and water levels are fluctuating wildly, as it does with climate change,” said Douglas W. Smith, a park biologist.

    And Yellowstone’s trumpeter swans are declining. By the early 20th century, hunters had wiped out most of the enormous birds in the continental United States, killing them for food and fashionable feathers. But 70 or so swans remained in the Yellowstone region, some of them safe inside the park. Those birds helped restore trumpeters nationwide. Now only two trumpeter pairs live in the park, and they have not bred successfully for several years.

    Part of the reason, said Dr. Smith and a colleague, Lauren E. Walker, may be the loss of nests and nesting sites during spring floods. A pair on Swan Lake, just south of Mammoth Hot Springs, has spurned the floating nest that the Park Service installed to help the birds.

    “Heritage-wise this is a really important population,” Dr. Walker said. “If this is no longer a reliable spot, what does that mean for the places that may have more human disturbance?”

    On the shores of Yellowstone Lake, dozens of late-season visitors watched two grizzly bears eating a carcass, while a coyote and some ravens circled, just a hundred or so yards from the road. “If they run this way,” the ranger called out, “get in your cars.”

    Grizzlies are omnivores, eating whatever is available, including the fat- and protein-packed nuts of the whitebark pine. That pine is perhaps the species most visibly affected by climate change in Yellowstone and throughout the West. Warmer temperatures have allowed a native pest, the mountain pine beetle, to better survive winter, move into high elevations and have a longer reproductive season. In the last 30 years, an estimated 80 percent of the whitebark pines in the park have died by fire, beetle, or fungal infection.

    For want of the whitebark pine, a great deal could be lost. The trees are a foundation species, meaning they play a central role in the structure of the ecosystem. They colonize exposed mountain sites, allowing other plants to get a root-hold. Their wide canopies protect snowpack from the sun. They are also a keystone species. They provide food for birds like the Clark’s nutcracker, which, in turn, create whitebark pine nurseries by caching nuts. And they are an important food source for squirrels, foxes, and grizzlies.

    When pine nuts are not plentiful, bears consume other foods, including the elk or deer innards left by hunters outside the park. And that can bring the Yellowstone-area grizzlies, relisted as threatened this September, into conflict with people.

    The loss of the pines “has far-reaching implications for the entire ecosystem,” said Jesse A. Logan, a retired Forest Service researcher.

    “The rest of the landscape, even in the mountainous West, has been so altered that Yellowstone becomes even more important,” Dr. Logan said.

    Yellowstone provides a refuge for people seeking and delighting in a sense of wilderness. It offers a landscape unlike any other: a largely intact ecosystem rich in wildlife and rich in geothermal features. Yellowstone’s unusual beauty was forged by volcanic heat; heat from humanity could be its undoing.

    Map showing Snow-telemetry (SNOTEL) weather stations in and near Yellowstone National Park. Left: Background shows average number of days per water year (October–September) with SWE greater than 0 cm. Right: Background shows average annual peak (greatest) SWE (cm). Data source = SNODAS [20]. Both panels are averaged over water years ending 2005– 2014, which was the length of record available for this data source. Gray areas = Lakes.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 9:28 am on November 11, 2018 Permalink | Reply
    Tags: "Becoming a Force While Trying to Avoid Disaster", Joan Tower, National Sawdust, NYT   

    From National Sawdust and the New York Times: “Becoming a Force While Trying to Avoid Disaster” 

    From National Sawdust

    National Sawdust

    A force in contemporary music, the composer Joan Tower turned 80 in September. Credit Lauren Lancaster for The New York Times

    At 80, Joan Tower Says Great Music Comes ‘in the Risks’

    Nov. 9, 2018
    William Robin

    When the composer Joan Tower went to Bennington College to study music, her teachers told her she needed to compose something.

    “So I wrote a piece,” she recalled recently, laughing, “and it was a disaster from beginning to end. I said, ‘I know I can do better than that.’ So I did that for the next 40 years, trying to create a piece that wasn’t a disaster.”

    Over the decades-long process of trying to avoid disaster — composition was, she said, “a very, very slow-moving juggernaut” — she became a force in contemporary music. She turned 80 in September, a birthday which will be celebrated on Sunday at National Sawdust in Brooklyn.

    In the tradition of Philip Glass @80 and John Corigliano @80 concerts, National Sawdust will celebrate Joan Tower in honor of her 80th Birthday. “One of the most successful women composers of all time” (The New Yorker) and one of the most important American composers alive today, Joan Tower has made lasting contributions to musical life for the past half century. With her iconic Silver Ladders, she was the first woman to win the prestigious Grawemeyer Award, and the recording of her Made In America won three different Grammy awards. In honor of her 80th birthday, National Sawdust is hosting an exclusive celebration, featuring an afternoon of music curated by Tower herself and featuring music written by Tower and friends Jennifer Higdon, Tania León, and Julia Wolfe.

    Joan Tower – Wild Summer for string quartet (The Jasper Quartet)
    Jennifer Higdon – Piano Trio (The Lysander Trio)
    Tania Leon – Ethos for piano quintet (The Cassatt Quartet with Ursula Oppens, piano)
    Julia Wolfe – Cha for saxophone quartet (PRISM quartet)

    PRISM Quartet
    Jasper Quartet
    Lysander Trio
    Cassatt Quartet
    Ursula Oppens, piano

    When she was young, Ms. Tower composed austere, pointillist music in the then-dominant 12-tone style, but soon turned toward a propulsive and visceral language. A gifted pianist, she founded the Da Capo Chamber Players, a pioneering ensemble dedicated to new music. She served as the St. Louis Symphony’s composer in residence in the 1980s, cultivating a taut, crackling orchestral sound, and has taught at Bard College for decades.

    Her widest-reaching project, the 2004 symphonic poem Made in America, has been performed by more than 65 orchestras in all 50 states. And Ms. Tower has recently been commissioned by the New York Philharmonic for a new work to debut in a future season. She is, in short, of comparable stature to the major octogenarians of her generation, such as Steve Reich, Charles Wuorinen and John Corigliano.

    Unlike some of those major octogenarians, however, Ms. Tower is remarkably self-deprecating. In a recent phone conversation from her home in Red Hook, N.Y., she talked about why. Here are edited excerpts.

    How does it feel to reach the milestone of 80?

    Composing is not an easy activity. For others, it’s easier, but for me it’s a very challenging activity. But as life goes on, the rewards come in. The credentials, like winning certain prizes, are very nice, but the important rewards are that your music gets picked up and played a lot. That’s what makes your life in music, not necessarily where you went to school, who you studied with, or what awards you got.

    Could you talk about some of your influences?

    [Growing up in South America,] I developed a love for percussion. My babysitter used to take me to these festivals. She would drop me off at the bandstand, so she could go and have fun. The band people would throw me a maraca or some kind of castanet or drum. That was where I started to develop a love of percussion and also dance. My music is basically about rhythm. It’s all about timing for me.

    But I also was studying piano at the time. I got very involved with Chopin, Beethoven, all the dead white European composers, who I loved. Beethoven was a huge influence on me, in terms of rhythm, pacing, juggling architectural narrative. Then I married a jazz musician, and I heard all the jazz greats. We went to all the clubs. Thelonious Monk, Bill Evans — all of them I got to hear live. That influence was more harmonic: I learned juicier chord progressions.

    You did graduate studies at Columbia University during the heyday of 12-tone music, but shifted toward a more tonal idiom. What prompted the change?

    What changed all that was Messiaen’s Quartet for the End of Time. I had never heard anything like this. It was colorful, it was direct, it was very slow at points. Oh my God, there was so much in that music that I was just blown away by. It came out of the sky. And then George Crumb’s Voice of the Whale. I was like, “Whoa, this is so consonant, and so beautiful, and so colorful.” So I started to pull away from the 12-tone group, and I started to develop my own voice.

    Ms. Tower in 1982, next to a poster announcing a performance of Sequoia by the New York Philharmonic. Credit G. Schirmer archives

    As you developed this new language, you also starting writing orchestral music, with Sequoia in 1981.

    The American Composers Orchestra was commissioning new works, and they asked me, and I said no, because I wasn’t ready. Francis Thorne, the lead energy behind that group, said, “You are ready, and I’m going to ask you again.” I wrote the piece kicking and screaming, and close to being tortured. [The conductor Leonard] Slatkin heard this piece and he loved it, and said, “I want you to be composer in residence with St. Louis.” I said, “No, I’m not ready for this. I only have one piece.”

    What was it that made you feel that you weren’t ready?

    I’ve always had a low opinion of myself. I think it’s a female thing, in a way. For women, in a field like composition, which has been male dominated for years and years and years, it’s a hard thing to walk into and feel that you are as empowered as your male colleagues are. That’s a very superficial answer to the question.

    But that’s how you felt?

    I did, and that continued for a long time. Until the last few years, actually.

    What changed?

    I got older [laughs]. And I got more confident, and more accepting of who I am, and what I can do.

    And you became more conscious of how women have been underrepresented in composition.

    The knowledge of this history started to build my confidence more and more, because I started to see what was going on. I started to see the rarity of women. All of the sudden, my eyes started opening to: “Are there any women on this recording? Are there any women on this panel?” I started to become more and more aware of the paucity of women in the infrastructure. I started taking stands and becoming an advocate.

    How has your style has changed in recent years?

    I’m not sure one has much control over that. My goal is to keep learning. There’s so much still to learn — the bass, the piccolo, I’m still working on, and the horn. Those are weak areas for me. I’m going to get there with those instruments at some point.

    What you try to do is write the best piece you can at whatever level of experience and voice that you are at. I know that if I take more risks, I’ll get there. It’s in the risks.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    National Sawdust is an unparalleled, artist-led, nonprofit venue, is a place for exploration and discovery. A place where emerging and established artists can share their music with serious music fans and casual listeners alike.

    In a city teeming with venues, National Sawdust is a singular space founded with an expansive vision: to provide composers and musicians across genres a home in which they can flourish, a setting where they are given unprecedented support and critical resources essential to create, and then share, their work.

    As a composer, I believe the role of an artist in the 21st century should be that of creator, educator, activist, and entrepreneur. I believe that 21st-century composers/artists need to be thinking about what impact they can have on their existing community, both locally and globally. At NS we believe in remaining flexible and true to the needs of artists. Our core mission is centered on the support of emerging artists, and on commissioning and supporting the seeds of ideas. Each year, we explore one large theme and construct programming and questions around that theme. This year, that theme is Origins. With this season, we are channeling the National Sawdust mission—empowering high-level artistry, regardless of training, genre, or fame—through multicultural artists who tell their stories through their music. Ultimately, Origins is a radical sharing of culture. We hope this cultural storytelling of the highest caliber will help bring our divided country closer together.

    We also believe the future of new art lives in education. To us, education is about giving young people and community members opportunities and tools to explore their potential for artistic and creative expression. But it is also about ensuring that artists themselves never stop learning – about their craft, about the work of their peers, about the business of the arts, about their own capacities to be educators and advocates. NS facilitates this kind of learning by bringing together artists from around the world in exciting composition- based projects, teaching opportunities, cultural exchanges, and hands-on management experience. Through this cultural synthesis artists leave lasting impressions on one another, become more versatile and resilient professionals, and create works that reflect a plural understanding of American society.

    –Paola Prestini, co-founder & Artist Director

    Space waiting

    John Schaefer

    For new music by living composers

    newsounds.org from New York Public Radio


    For great Jazz

    88.3FM http://wbgo.org/

    WPRB 103.3FM

    Please visit The Jazz Loft Project based on the work of Sam Stephenson
    Please visit The Jazz Loft Radio project from New York Public Radio

  • richardmitnick 3:46 pm on October 30, 2018 Permalink | Reply
    Tags: , , Dame Susan Jocelyn Bell Burnell and pulsars, , , , , NYT, Reinhard Genzel of the Max Planck Institute for Extraterrestrial Physics, S0-2, , , Vera Rubin and Dark Matter   

    From The New York Times: “Trolling the Monster in the Heart of the Milky Way” 

    New York Times

    From The New York Times

    Oct. 30, 2018
    Dennis Overbye

    In a dark, dusty patch of sky in the constellation Sagittarius, a small star, known as S2 or, sometimes, S0-2, cruises on the edge of eternity. Every 16 years, it passes within a cosmic whisker of a mysterious dark object that weighs some 4 million suns, and that occupies the exact center of the Milky Way galaxy.

    Star S0-2 Keck/UCLA Galactic Center Group

    For the last two decades, two rival teams of astronomers, looking to test some of Albert Einstein’s weirdest predictions about the universe, have aimed their telescopes at the star, which lies 26,000 light-years away. In the process, they hope to confirm the existence of what astronomers strongly suspect lies just beyond: a monstrous black hole, an eater of stars and shaper of galaxies.

    For several months this year, the star streaked through its closest approach to the galactic center, producing new insights into the behavior of gravity in extreme environments, and offering clues to the nature of the invisible beast in the Milky Way’s basement.

    One of those teams, an international collaboration based in Germany and Chile, and led by Reinhard Genzel, of the Max Planck Institute for Extraterrestrial Physics, say they have found the strongest evidence yet that the dark entity is a supermassive black hole, the bottomless grave of 4.14 million suns.

    ESO VLT at Cerro Paranal in the Atacama Desert, •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).
    elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo

    ESO VLT 4 lasers on Yepun

    The evidence comes in the form of knots of gas that appear to orbit the galactic center. Dr. Genzel’s team found that the gas clouds circle every 45 minutes or so, completing a circuit of 150 million miles at roughly 30 percent of the speed of light. They are so close to the alleged black hole that if they were any closer they would fall in, according to classical Einsteinian physics.

    Astrophysicists can’t imagine anything but a black hole that could be so massive, yet fit within such a tiny orbit.

    The results provide “strong support” that the dark thing in Sagittarius “is indeed a massive black hole,” Dr. Genzel’s group writes in a paper that will be published on Wednesday under the name of Gravity Collaboration, in the European journal Astronomy & Astrophysics.

    “This is the closest yet we have come to see the immediate zone around a supermassive black hole with direct, spatially resolved techniques,” Dr. Genzel said in an email.

    Reinhard Genzel runs the Max Planck Institute for Extraterrestrial Physics in Munich. He has been watching S2, in the constellation Sagittarius, hoping it will help confirm the existence of a supermassive black hole.Credit Ksenia Kuleshova for The New York Times.

    The work goes a long way toward demonstrating what astronomers have long believed, but are still at pains to prove rigorously: that a supermassive black hole lurks in the heart not only of the Milky Way, but of many observable galaxies. The hub of the stellar carousel is a place where space and time end, and into which stars can disappear forever.

    The new data also help to explain how such black holes can wreak havoc of a kind that is visible from across the universe. Astronomers have long observed spectacular quasars and violent jets of energy, thousands of light-years long, erupting from the centers of galaxies.

    Roger Blandford, the director of the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University, said that there is now overwhelming evidence that supermassive black holes are powering such phenomena.

    “There is now a large burden of proof on claims to the contrary,” he wrote in an email. “The big questions involve figuring out how they work, including disk and jets. It’s a bit like knowing that the sun is a hot, gaseous sphere and trying to understand how the nuclear reactions work.”

    Images of different galaxies — some of which have evocative names like the Black Eye Galaxy, bottom left, or the Sombrero Galaxy, second left — adorn a wall at the Max Planck Institute.Credit Ksenia Kuleshova for The New York Times.

    Sheperd Doeleman, a radio astronomer at the Harvard-Smithsonian Center for Astrophysics, called the work “a tour de force.” Dr. Doeleman studies the galactic center and hopes to produce an actual image of the black hole, using a planet-size instrument called the Event Horizon Telescope.

    Event Horizon Telescope Array

    Arizona Radio Observatory
    Arizona Radio Observatory/Submillimeter-wave Astronomy (ARO/SMT)

    Atacama Pathfinder EXperiment

    CARMA Array no longer in service
    Combined Array for Research in Millimeter-wave Astronomy (CARMA)

    Atacama Submillimeter Telescope Experiment (ASTE)
    Atacama Submillimeter Telescope Experiment (ASTE)

    Caltech Submillimeter Observatory
    Caltech Submillimeter Observatory (CSO)

    IRAM NOEMA interferometer
    Institut de Radioastronomie Millimetrique (IRAM) 30m

    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA
    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA

    Large Millimeter Telescope Alfonso Serrano
    Large Millimeter Telescope Alfonso Serrano

    CfA Submillimeter Array Hawaii SAO
    Submillimeter Array Hawaii SAO

    ESO/NRAO/NAOJ ALMA Array, Chile

    South Pole Telescope SPTPOL
    South Pole Telescope SPTPOL

    NSF CfA Greenland telescope

    Greenland Telescope

    Future Array/Telescopes

    Plateau de Bure interferometer
    Plateau de Bure interferometer

    The study is also a major triumph for the European Southern Observatory, a multinational consortium with headquarters in Munich and observatories in Chile, which had made the study of S2 and the galactic black hole a major priority. The organization’s facilities include the Very Large Telescope [shown above], an array of four giant telescopes in Chile’s Atacama Desert (a futuristic setting featured in the James Bond film “Quantum of Solace”), and the world’s largest telescope, the Extremely Large Telescope, now under construction on a mountain nearby.

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).

    Einstein’s bad dream

    Black holes — objects so dense that not even light can escape them — are a surprise consequence of Einstein’s general theory of relativity, which ascribes the phenomenon we call gravity to a warping of the geometry of space and time. When too much matter or energy are concentrated in one place, according to the theory, space-time can jiggle, time can slow and matter can shrink and vanish into those cosmic sinkholes.

    Einstein didn’t like the idea of black holes, but the consensus today is that the universe is speckled with them. Many are the remains of dead stars; others are gigantic, with the masses of millions to billions of suns. Such massive objects seem to anchor the centers of virtually every galaxy, including our own. Presumably they are black holes, but astronomers are eager to know whether these entities fit the prescription given by Einstein’s theory.

    Andrea Ghez, astrophysicist and professor at the University of California, Los Angeles, who leads a team of scientists observing S2 for evidence of a supermassive black hole UCLA Galactic Center Group

    Although general relativity has been the law of the cosmos ever since Einstein devised it, most theorists think it eventually will have to be modified to explain various mysteries, such as what happens at the center of a black hole or at the beginning of time; why galaxies clump together, thanks to unidentified stuff called dark matter; and how, simultaneously, a force called dark energy is pushing these clumps of galaxies apart.

    Women in STEM – Vera Rubin

    Fritz Zwicky discovered Dark Matter when observing the movement of the Coma Cluster

    Coma cluster via NASA/ESA Hubble

    But most of the real work was done by Vera Rubin

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

    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

    Dark Energy Survey

    Dark Energy Camera [DECam], built at FNAL

    NOAO/CTIO Victor M Blanco 4m Telescope which houses the DECam at Cerro Tololo, Chile, housing DECam at an altitude of 7200 feet

    The existence of smaller black holes was affirmed two years ago, when the Laser Interferometer Gravitational-Wave Observatory, or LIGO, detected ripples in space-time caused by the collision of a pair of black holes located a billion light-years away.

    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    Caltech/MIT Advanced aLigo Hanford, WA, USA installation

    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project

    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger

    ESA/eLISA the future of gravitational wave research

    Skymap showing how adding Virgo to LIGO helps in reducing the size of the source-likely region in the sky. (Credit: Giuseppe Greco (Virgo Urbino group)

    But those black holes were only 20 and 30 times the mass of the sun; how supermassive black holes behave is the subject of much curiosity among astronomers.

    “We already know Einstein’s theory of gravity is fraying around the edges,” said Andrea Ghez, a professor at the University of California, Los Angeles. “What better places to look for discrepancies in it than a supermassive black hole?” Dr. Ghez is the leader of a separate team that, like Dr. Genzel’s, is probing the galactic center. “What I like about the galactic center is that you get to see extreme astrophysics,” she said.

    Despite their name, supermassive black holes are among the most luminous objects in the universe. As matter crashes down into them, stupendous amounts of energy should be released, enough to produce quasars, the faint radio beacons from distant space that have dazzled and baffled astronomers since the early 1960s.

    Women in STEM – Dame Susan Jocelyn Bell Burnell

    Dame Susan Jocelyn Bell Burnell, discovered pulsars with radio astronomy. Jocelyn Bell at the Mullard Radio Astronomy Observatory, Cambridge University, taken for the Daily Herald newspaper in 1968. Denied the Nobel.

    Dame Susan Jocelyn Bell Burnell 2009

    Dame Susan Jocelyn Bell Burnell (1943 – ), still working from http://www. famousirishscientists.weebly.com

    Astronomers have long suspected that something similar could be happening at the center of the Milky Way, which is marked by a dim source of radio noise called Sagittarius A* (pronounced Sagittarius A-star).

    Sgr A* from ESO VLT

    SgrA* NASA/Chandra

    SGR A* , the supermassive black hole at the center of the Milky Way. NASA’s Chandra X-Ray Observatory

    But the galactic center is veiled by dust, making it all but invisible to traditional astronomical ways of seeing.

    Seeing in the dark

    Reinhard Genzel grew up in Freiburg, Germany, a small city in the Black Forest. As a young man, he was one of the best javelin throwers in Germany, even training with the national team for the 1972 Munich Olympics. Now he is throwing deeper.

    He became interested in the dark doings of the galactic center back in the 1980s, as a postdoctoral fellow at the University of California, Berkeley, under physicist Charles Townes, a Nobel laureate and an inventor of lasers. “I think of myself as a younger son of his,” Dr. Genzel said in a recent phone conversation.

    In a series of pioneering observations in the early 1980s, using detectors that can see infrared radiation, or heat, through galactic dust, Dr. Townes, Dr. Genzel and their colleagues found that gas clouds were zipping around the center of the Milky Way so fast that the gravitational pull of about 4 million suns would be needed to keep it in orbit. But whatever was there, it emitted no starlight. Even the best telescopes, from 26,000 light years away, could make out no more than a blur.

    An image of the central Milky Way, which contains Sagittarius A*, taken by the VISTA telescope at the E.S.O.’s Paranal Observatory, mounted on a peak just next to the Very Large Telescope.CreditEuropean Southern Observatory/VVV Survey/D. Minniti/Ignacio Toledo, Martin Kornmesser

    Part of ESO’s Paranal Observatory, the VLT Survey Telescope (VISTA) observes the brilliantly clear skies above the Atacama Desert of Chile. It is the largest survey telescope in the world in visible light.
    Credit: ESO/Y. Beletsky, with an elevation of 2,635 metres (8,645 ft) above sea level

    Two advances since then have helped shed some figurative light on whatever is going on in our galaxy’s core. One was the growing availability in the 1990s of infrared detectors, originally developed for military use. Another was the development of optical techniques that could drastically increase the ability of telescopes to see small details by compensating for atmospheric turbulence. (It’s this turbulence that blurs stars and makes them twinkle.)

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT.

    These keen eyes revealed hundreds of stars in the galaxy’s blurry core, all buzzing around in a circle about a tenth of a light year across. One of the stars, which Dr. Genzel calls S2 and Dr. Ghez calls S-02, is a young blue star that follows a very elongated orbit and passes within just 11 billion miles of the mouth of the putative black hole every 16 years.

    During these fraught passages, the star, yanked around an egg-shaped orbit at speeds of up to 5,000 miles per second, should experience the full strangeness of the universe according to Einstein. Intense gravity on the star’s surface should slow the vibration of light waves, stretching them and making the star appear redder than normal from Earth.

    This gravitational redshift, as it is known, was one of the first predictions of Einstein’s theory. The discovery of S2 offered astronomers a chance to observe the phenomenon in the wild — within the grip of gravity gone mad, near a supermassive black hole.

    Left, calculations left out at the Max Planck Institute, viewed from above, right.Credit Ksenia Kuleshova for The New York Times

    In the wheelhouse of the galaxy

    To conduct that experiment, astronomers needed to know the star’s orbit to a high precision, which in turn required two decades of observations with the most powerful telescopes on Earth. “You need twenty years of data just to get a seat at this table,” said Dr. Ghez, who joined the fray in 1995.

    And so, the race into the dark was joined on two different continents. Dr. Ghez worked with the 10-meter Keck telescopes, located on Mauna Kea, on Hawaii’s Big Island.

    Keck Observatory, Maunakea, Hawaii, USA.4,207 m (13,802 ft), above sea level, showing also NASA’s IRTF and NAOJ Subaru

    UCO Keck Laser Guide Star Adaptive Optics

    Dr. Genzel’s group benefited from the completion of the European Southern Observatory’s brand new Very Large Telescope [above] array in Chile.

    The European team was aided further by a new device, an interferometer named Gravity, that combined the light from the array’s four telescopes.

    ESO GRAVITY insrument on The VLTI, interferometric instrument operating in the K band, between 2.0 and 2.4 μm. It combines 4 telescope beams and is designed to peform both interferometric imaging and astrometry by phase referencing. Credit: MPE/GRAVITY team

    Designed by a large consortium led by Frank Eisenhauer of the Max Planck Institute, the instrument enabled the telescope array to achieve the resolution of a single mirror 130 meters in diameter. (The name originally was an acronym for a long phrase that included words such as “general,” “relativity,” and “interferometry,” Dr. Eisenhauer explained in an email.)

    “All of the sudden, we can see 1,000 times fainter than before,” said Dr. Genzel in 2016, when the instrument went into operation. In addition, they could track the movements of the star S2 from day to day.

    Meanwhile, Dr. Ghez was analyzing the changing spectra of light from the star, to determine changes in the star’s velocity. The two teams leapfrogged each other, enlisting bigger and more sophisticated telescopes, and nailing down the characteristics of S2. In 2012 Dr. Genzel and Dr. Ghez shared the Crafoord Prize in astronomy, an award nearly as prestigious as the Nobel. Events came to head this spring and summer, during a six-month period when S2 made its closest approach to the black hole.

    “It was exciting in the middle of April when a signal emerged and we started getting information,” Dr. Ghez said.

    On July 26, Dr. Genzel and Dr. Eisenhauer held a news conference in Munich to announce that they had measured the long-sought gravitational redshift. As Dr. Eisenhauer marked off their measurements, which matched a curve of expected results, the room burst into applause.

    “The road is wide open to black hole physics,” Dr. Eisenhauer proclaimed.

    In an email a month later, Dr. Genzel explained that detecting the gravitational redshift was only the first step: “I am usually a fairly sober, and sometimes pessimistic person. But you may sense my excitement as I write these sentences, because of these wonderful results. As a scientist (and I am 66 years old) one rarely if ever has phases this productive. Carpe Diem!”

    In early October, Dr. Ghez, who had waited to observe one more phase of the star’s trip, said her team soon would publish their own results.

    A monster in the basement

    In the meantime, Dr. Genzel was continuing to harvest what he called “this gift from nature.”

    The big break came when his team detected evidence of hot spots, or “flares,” in the tiny blur of heat marking the location of the suspected black hole. A black hole with the mass of 4 million suns should have a mouth, or event horizon, about 16 million miles across — too small for even the Gravity instrument to resolve from Earth.

    The hot spots were also too small to make out. But they rendered the central blur lopsided, with more heat on one side of the blur than the other. As a result, Dr. Genzel’s team saw the center of that blur of energy shift, or wobble, relative to the position of S2, as the hot spot went around it.

    As a result, said Dr. Genzel, “We see a little loop on the sky.” Later he added, “This is the first time we can study these important magnetic structures in a spatially resolved manner just like in a physics laboratory.”

    He speculated that the hot spots might be produced by shock waves in magnetic fields, much as solar flares erupt from the sun. But this might be an overly simplistic model, the authors cautioned in their paper. The effects of relativity turn the neighborhood around the black hole into a hall of mirrors, Dr. Genzel said: “Our statements currently are still fuzzy. We will have to learn better to reconstruct reality once we better understand exactly these mirages.”

    The star has finished its show for this year. Dr. Genzel hopes to gather more data from the star next year, as it orbits more distantly from the black hole. Additional observations in the coming years may clarify the star’s orbit, and perhaps answer other questions, such as whether the black hole was spinning, dragging space-time with it like dough in a mixer.

    But it may be hard for Dr. Genzel to beat what he has already accomplished, he said by email. For now, shrink-wrapping 4 million suns worth of mass into a volume just 45 minutes around was a pretty good feat “for a small boy from the countryside.”

    See the full article here .


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  • richardmitnick 10:10 am on October 29, 2018 Permalink | Reply
    Tags: A.I. Is Helping Scientists Predict When and Where the Next Big Earthquake Will Be, , , , NYT   

    From The New York Times: “A.I. Is Helping Scientists Predict When and Where the Next Big Earthquake Will Be” 

    New York Times

    From The New York Times

    Oct. 26, 2018

    Thomas Fuller
    Cade Metz

    Jean-Francois Podevin

    Countless dollars and entire scientific careers have been dedicated to predicting where and when the next big earthquake will strike. But unlike weather forecasting, which has significantly improved with the use of better satellites and more powerful mathematical models, earthquake prediction has been marred by repeated failure.

    Some of the world’s most destructive earthquakes — China in 2008, Haiti in 2010 and Japan in 2011, among them — occurred in areas that seismic hazard maps had deemed relatively safe. The last large earthquake to strike Los Angeles, Northridge in 1994, occurred on a fault that did not appear on seismic maps.

    Now, with the help of artificial intelligence, a growing number of scientists say changes in the way they can analyze massive amounts of seismic data can help them better understand earthquakes, anticipate how they will behave, and provide quicker and more accurate early warnings.

    “I am actually hopeful for the first time in my career that we will make progress on this problem,” said Paul Johnson, a fellow at the Los Alamos National Laboratory who is among those at the forefront of this research.

    Well aware of past earthquake prediction failures, scientists are cautious when asked how much progress they have made using A.I. Some in the field refer to prediction as “the P word,” because they do not even want to imply it is possible. But one important goal, they say, is to be able to provide reliable forecasts.

    The earthquake probabilities that are provided on seismic hazard maps, for example, have crucial consequences, most notably in instructing engineers how they should construct buildings. Critics say these maps are remarkably inexact.

    A map of Los Angeles lists the probability of an earthquake producing strong shaking within a given period of time — usually 50 years. That is based on a complex formula that takes into account, among other things, the distance from a fault, how fast one side of a fault is moving past the other, and the recurrence of earthquakes in the area.


    A study led by Katherine M. Scharer, a geologist with the United States Geological Survey, estimated dates for nine previous earthquakes along the Southern California portion of the San Andreas fault dating back to the eighth century. The last big earthquake on the San Andreas was in 1857.

    Since the average interval between these big earthquakes was 135 years, a common interpretation is that Southern California is due for a big earthquake. Yet the intervals between earthquakes are so varied — ranging from 44 years to 305 years — that taking the average is not a very useful prediction tool. A big earthquake could come tomorrow, or it could come in a century and a half or more.

    This is one of the criticisms of Philip Stark, an associate dean at the University of California, Berkeley, at the Division of Mathematical and Physical Sciences. Dr. Stark describes the overall system of earthquake probabilities as “somewhere between meaningless and misleading” and has called for it to be scrapped.

    The new A.I.-related earthquake research is leaning on neural networks, the same technology that has accelerated the progress of everything from talking digital assistants to driverless cars. Loosely modeled on the web of neurons in the human brain, a neural network is a complex mathematical system that can learn tasks on its own.

    Scientists say seismic data is remarkably similar to the audio data that companies like Google and Amazon use in training neural networks to recognize spoken commands on coffee-table digital assistants like Alexa. When studying earthquakes, it is the computer looking for patterns in mountains of data rather than relying on the weary eyes of a scientist.

    “Rather than a sequence of words, we have a sequence of ground-motion measurements,” said Zachary Ross, a researcher in the California Institute of Technology’s Seismological Laboratory who is exploring these A.I. techniques. “We are looking for the same kinds of patterns in this data.”

    Brendan Meade, a professor of earth and planetary sciences at Harvard, began exploring these techniques after spending a sabbatical at Google, a company at the forefront of A.I. research.

    His first project showed that, at the very least, these machine-learning methods could significantly accelerate his experiments. He and his graduate students used a neural network to run an earthquake analysis 500 times faster than they could in the past. What once took days now took minutes.

    Dr. Meade also found that these A.I. techniques could lead to new insights. In the fall, with other researchers from Google and Harvard, he published a paper showing how neural networks can forecast earthquake aftershocks. This kind of project, he believes, represents an enormous shift in the way earthquake science is done. Similar work is underway at places like Caltech and Stanford University.

    “We are at a point where the technology can do as well as — or better than — human experts,” Dr. Ross said.

    Driving that guarded optimism is the belief that as sensors get smaller and cheaper, scientists will be able to gather larger amounts of seismic data. With help from neural networks and similar A.I. techniques, they hope to glean new insights from all this data.

    Dr. Ross and other Caltech researchers are using these techniques to build systems that can more accurately recognize earthquakes as they are happening and anticipate where the epicenter is and where the shaking will spread.

    Japan and Mexico have early warning systems, and California just rolled out its own. But scientists say artificial intelligence could greatly improve their accuracy, helping predict the direction and intensity of a rupture in the earth’s crust and providing earlier warnings to hospitals and other institutions that could benefit from a few extra seconds of preparation.

    “The more detail you have, the better your forecasts will be,” Dr. Ross said.

    Scientists working on these projects said neural networks have their limits. Though they are good at finding familiar signals in data, they are not necessarily suited to finding new kinds of signals — like the sounds tectonic plates make as they grind together.

    But at Los Alamos, Dr. Johnson and his colleagues have shown that a machine-learning technique called “random forests” can identify previously unknown signals in a simulated fault created inside a lab. In one case, their system showed that a particular sound made by the fault, which scientists previously thought was meaningless, was actually an indication of when an earthquake would arrive.

    Some scientists, like Robert Geller, a seismologist at the University of Tokyo, are unconvinced that A.I. will improve earthquake forecasts. He questions the very premise that past earthquakes can predict future ones. And ultimately, he said, we would only know the effectiveness of A.I. forecasting when earthquakes can be predicted beyond random chance.

    “There are no shortcuts,” Dr. Geller said. “If you cannot predict the future, then your hypothesis is wrong.”

    See the full article here .

    Earthquake Alert


    Earthquake Alert

    Earthquake Network projectEarthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.


    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan


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    Stem Education Coalition

  • richardmitnick 9:16 pm on August 30, 2018 Permalink | Reply
    Tags: “as a child you’d ask her a question a classic childhood question like ‘Why does the sun come up in the morning’ and my mum would always have a very complicated answer.”, Her boss J.L. Pawsey valued her judgment and experience so highly that when she was absent from a meeting he would often not make a final decision until she had been consulted, Her colleagues at the government research center considered her so integral to their work that they helped keep her marriage a secret she wore her wedding band on a necklace, Her final contribution “predicted the whole future of radio astronomy", In the end she was forced to resign and give up her pension, NYT, Obituaries of the overlooked, Payne-Scott would later discover two more types of solar bursts and help create a device called the swept-lobe interferometer, , Ruby Payne-Scott Who Explored Space With Radio Waves, She earned bachelor’s and master’s degrees in physics from the University of Sydney — only the third woman to do so, She maintained her secret for several years during which she helped Pawsey discover what would become known as Type I solar bursts, She was told that as a married woman she could not work full time   

    From The New York Times: Overlooked No More: “Ruby Payne-Scott, Who Explored Space With Radio Waves” 

    New York Times

    From The New York Times


    Payne-Scott helped establish the field of radio astronomy by using radio waves to detect solar bursts, but she was forced to resign after she got married.

    Ruby Payne-Scott in an undated photograph. In the 1940s, she helped lay the foundation for a new field of science called radio astronomy.

    Aug. 29, 2018
    Rebecca Halleck

    Since 1851, obituaries in The New York Times have been dominated by white men. With Overlooked, we’re adding the stories of remarkable people whose deaths went unreported in The Times.

    Every so often our sun emits an invisible burst of energy.

    This energy ripples through space as electromagnetic waves and then crashes into planets and meteors and space debris and one another, causing a great cacophony above and around us.

    A cacophony that was inaudible, until Ruby Payne-Scott entered a laboratory.

    In the 1940s, Payne-Scott helped lay the foundation for a new field of science called radio astronomy. Her work led to the discovery of deep-space phenomena like black holes and pulsars and later helped astronauts understand how solar storms disrupt weather in space and electrical grids on Earth.

    Yet as a married woman she was denied equal employment status and compensation. She challenged the scientific establishment in her native Australia and fought for the rights of women in the workplace, but ultimately left science to raise her children full time.


    World War II opened the door to Payne-Scott’s scientific career. The Australian armed forces needed physicists, and men were joining the military to fight instead.

    Bored with her job at Amalgamated Wireless (Australasia), where she cataloged and calibrated equipment for radio technicians, Payne-Scott applied for a government posting seeking a physicist. Her experience piqued the interest of the government’s Council for Scientific and Industrial Research. There she became one of two women working as research scientists in the division of radio physics, a laboratory with a top-secret mission: to enable radar systems to track incoming Japanese fighter planes.

    Radar was already in use on the European front, but the same systems were not working properly in the Southern Hemisphere, leaving Allied forces and Australian citizens vulnerable.

    Payne-Scott determined that tropical weather in the Pacific was to blame. She created a device called an S-band noise tube to check the sensitivity of receivers and measure the intensity of incoming signals.

    “She understood the hardware, but she also understood the physics, which is incredible,” said Miller Goss, astronomer emeritus at the National Radio Astronomy Observatory and the author of Making Waves, a biography of Payne-Scott. “No radio astronomer in the 21st century could do something like that.”

    Payne-Scott became an expert at distinguishing Japanese aircraft from other sources of radio static, like ships, lighthouses, buildings and cliffs. This enabled scientists to track planes from farther away, even at night and during storms — a vast improvement over relying on the naked eye to spot the enemy.

    By 1944, with the war turning in the Allies’ favor, Payne-Scott and other scientists began searching for postwar applications for their research. A British physicist, James Stanley Hey, wrote a classified report that was circulated among just a few Allied scientists, including Payne-Scott. It hypothesized that a mysterious radio noise was coming not from aircraft or signal jamming, but rather from the sun.

    Hey’s report inspired Payne-Scott to join the race to legitimize a new branch of science: radio astronomy.

    Ruby Violet Payne-Scott was born in South Grafton, New South Wales, on May 28, 1912, to Cyril and Amy (Neale) Payne-Scott. Home-schooled until age 11, she ultimately landed a spot at the prestigious Sydney Girls High School, graduating at 16. She earned bachelor’s and master’s degrees in physics from the University of Sydney — only the third woman to do so, Goss said in an interview.

    But there were few opportunities for physicists or women when Payne-Scott earned her graduate degree in 1936, so she became a schoolteacher and then took the job at Amalgamated Wireless.

    She married William Hall in 1944. They shared political views that were fairly radical; they were feminists, environmental conservationists, atheists and communists. Some of Payne-Scott’s colleagues called her “Red Ruby.”

    But her marriage would present a problem: Women in public service were expected to resign when they wed. Her colleagues at the government research center considered her so integral to their work that they helped keep her marriage a secret; she wore her wedding band on a necklace.

    Ms. Payne-Scott visiting with colleagues at a conference in 1952, a year after she left her job at an Australian government laboratory. She was told that as a married woman she could not work full time.Credit ATNF Historical Photographic Archive

    Her boss, J.L. Pawsey, “valued her judgment and experience so highly that when she was absent from a meeting, he would often not make a final decision until she had been consulted,” Goss wrote in Making Waves.

    She maintained her secret for several years, during which she helped Pawsey discover what would become known as Type I solar bursts. Their work, published in the journal Nature in February 1946 [related ;Springer Link, demonstrated that electromagnetic waves were spewing from the sun. Unlike solar flares, which were visible during eclipses using traditional telescopes, these spontaneous emissions were now detectable using radios.

    Payne-Scott would later discover two more types of solar bursts and help create a device called the swept-lobe interferometer, which panned the sky dozens of times per second, allowing radio astronomers to identify and zoom in on single wave formations.

    Her final contribution “predicted the whole future of radio astronomy,” Goss said. Like watching an instant replay from multiple camera angles at the same time, her method gave radio astronomers a more complete picture of the frequency and shape of waves emanating from space. Martin Ryle shared the 1974 Nobel Prize in Physics using this method.

    Then, in 1950, the department was restructured, and in the process Payne-Scott’s marriage was uncovered by regulators.

    “There were many men who were very unsympathetic to the notion that women would continue to work after they were married,” said Claire Hooker, senior lecturer in health and medical humanities at the University of Sydney.

    “You didn’t have two breadwinners in the family,” she continued. “And it was just assumed that it was the man’s job to win the bread.”

    Payne-Scott challenged the rule, taking her fight to the head of the department in a series of contentious letters. But she was forced to resign and give up her pension.

    Pawsey hired her back on “temporary” status and gave her a raise, but she decided to leave the lab a year later, five months pregnant and excited to become a mother.

    Her son, Peter Gavin Hall, became an influential statistician. Her daughter, Fiona Margaret Hall, born in 1953, is a prominent Australian artist currently working on a war memorial.

    Payne-Scott died of complications of dementia on May 25, 1981. She was 68.

    Hall said in an interview that while her mother was known publicly for being outspoken, she lived a relatively quiet family life in the suburbs of Sydney — except for the occasional trip to protest the Vietnam War.

    But sometimes, she said, “as a child you’d ask her a question, a classic childhood question like ‘Why does the sun come up in the morning,’ and my mum would always have a very complicated answer.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 1:50 pm on August 6, 2018 Permalink | Reply
    Tags: , , , , NYT, Space comes to Senegal from NASA   

    From The New York Times : “Aiming for the Stars, and a Chunk of Rock, in Senegal” 

    New York Times

    From The New York Times

    Aug. 5, 2018
    Jaime Yaya Barry
    Dionne Searcey

    Outside Dakar, people got a look at the heavens last week through one of the New Horizons space program’s telescopes.Credit Tomas Munita for The New York Times.

    When Salma Sylla was a little girl, she tried to find relief from Senegal’s steamy hot season by retreating to the roof of her home to sleep. Restless and overheated, she would lie awake staring at the stars.

    The area where she lived outside Dakar, the capital, had no electricity, and the heavens sparkled. She tried to count the stars, realizing more shone on some nights than on others.

    Ms. Sylla, now 37, was intrigued. But studying the stars in Senegal was not easy: High school courses were limited; libraries rarely had books on space; telescopes were few and expensive.

    Not much has improved since Ms. Sylla was a girl; astronomy offerings are extremely limited in Senegal’s universities. But officials here hope to change that, as part of a mission to improve science, technology, engineering and math skills by bolstering the country’s university programs and building a science and research center.

    The undertaking is part of “Emerging Senegal,” a broad development strategy by President Macky Sall that also includes plans for a planetarium.

    The effort got a lift last week, when Senegal welcomed a team of more than three dozen scientists from the United States and France, part of NASA’s New Horizons program. The scientists fanned out across the countryside in hopes of observing the silhouette cast by an ancient chunk of rock orbiting beyond Pluto as it passed in front of a bright star.

    The viewing was intended to help the team prepare for when the plutonium-powered New Horizons spacecraft passes by the object — nicknamed Ultima Thule (Beyond the Known World) — on New Year’s Eve.

    Brigitte Anderson, an American scientist, set a telescope with the help of Modou Mbaye, a Senegalese scientist. Credit Tomas Munita for The New York Times.

    “This is the farthest exploration of anything in space that has ever taken place, by quite a lot,” said Alan Stern, project leader for NASA’s New Horizons mission. “We are way, way out there.”

    For the scientists, coming to Senegal was a process of elimination. Most of the areas that offered the best viewing were in the middle of the Atlantic Ocean. The other options — in neighboring Mali, for example — were in areas patrolled by violent extremists.

    The countryside of Senegal is peaceful, parts of it do not have electricity, and many rural areas are sparsely populated. That was a bonus for the scientists, who wanted a clear sky, free of light. Still, Senegal was a risky proposition. The area is on the cusp of the rainy season, and cloudy skies threatened to block the event, which occurred early Saturday and lasted less than a second.

    Scientists are still evaluating data from the viewing, but the skies turned out to be clear and they are hopeful.

    Senegal was an enthusiastic host. About two dozen Senegalese astronomers and scientists, including Ms. Sylla, accompanied the New Horizons team in the field and contributed to the viewing.

    African countries have racked up their own space achievements. Moroccan astronomers have discovered comets, asteroids and planets outside our solar system. Ghana’s first satellite is now orbiting the earth. Students in Tunisia have organized public events to observe the sky, even though they do not have an observatory.

    “Astronomy is virtually as popular in Africa as it is everywhere in the world,” said David Baratoux, the president of the African Initiative for Planetary Sciences and Space, who is based in France.

    The biggest hindrance is money. The United States spends more on its space program than the value of Senegal’s entire economy. The 21 high-powered telescopes brought by the New Horizons team were nearly double the number of telescopes available in all of Senegal.

    The New Horizons team hopes that the telescopes in Senegal and a handful in Colombia, with some assistance from the Hubble Space Telescope, will answer some questions about Ultima Thule, part of the Kuiper belt, before its spacecraft arrives. Is it shaped like a potato, for instance, or is it actually two objects orbiting each other?

    Last week, at a late-night dress rehearsal for Saturday’s viewing, Diarra Dieng, an applied physics student in Dakar, tweaked the settings on a $3,500 telescope, guided by a NASA scientist.

    “This is amazing,” she said, as she tried to train the telescope on the correct star.

    Instructors at Ms. Dieng’s high school in Dakar had encouraged her to pursue studies in science, but she was skeptical at first. “I never knew girls could do this kind of work,” she said.

    The New Horizons team had spread across the lawn of a conference center to work out equipment kinks ahead of the viewing. The biggest problem came when someone accidentally turned on the sprinkler system.

    The scientists let anyone milling about the nearby parking lot get a view of Saturn and Mars. Students who had studied astronomy through online courses joined a long line. Fathers hoisted small children to the eyepiece. The minister of higher education took a peek.

    “Mmmmm,” was all one woman could say, shaking her head as if in disbelief.

    The higher education minister, Mary Teuw Niane, said he hoped the team’s visit would foster future student collaborations with NASA.

    Anne Verbiscer, an astronomy professor at the University of Virginia and part of the New Horizons team, said she valued working with Senegalese students and could relate to overcoming hurdles in pursuing a career in astronomy.

    Dr. Verbiscer was 5 when a human first walked on the moon in 1969. Transfixed by the Apollo mission, she wanted to be an astronaut for Halloween. So she shopped for a costume with her mother and finally found one: It was in the boys’ section.

    In Senegal, Ms. Sylla remembers her grandmother telling her the stars were obscured some nights to help hyena hunters go undetected. Her quest to find out what was really happening in the skies led her to persist. She cobbled together studies at Senegalese institutions and abroad.

    Today, Ms. Sylla is the first Ph.D. student in astronomy at Cheikh Anta Diop University in Dakar.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

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