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  • richardmitnick 12:38 pm on June 25, 2020 Permalink | Reply
    Tags: "A* Model", , , , , Physicists' innovative model provides insight into the behavior of the black hole at the center of our galaxy., UC Santa Barbara   

    From UC Santa Barbara: “A* Model” 

    UC Santa Barbara Name bloc
    From UC Santa Barbara

    June 15, 2020
    Harrison Tasoff
    (805) 893-7220
    harrisontasoff@ucsb.edu

    Physicists’ innovative model provides insight into the behavior of the black hole at the center of our galaxy.

    A simulation of light emission around Sagittarius A* as gas spirals inward over the course of around 53 hours.

    Like most galaxies, the Milky Way hosts a supermassive black hole at its center. Called Sagittarius A*, the object has captured astronomers’ curiosity for decades. And now there is an effort to image it directly.

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


    SgrA* NASA/Chandra supermassive black hole at the center of the Milky Way, X-ray image of the center of our galaxy, where the supermassive black hole Sagittarius A* resides. Image via X-ray: NASA/UMass/D.Wang et al., IR: NASA/STScI.


    Sgr A* from ESO VLT


    SGR A and SGR A* from Penn State and NASA/Chandra

    Catching a good photo of the celestial beast will require a better understanding of what’s going on around it, which has proved challenging due to the vastly different scales involved. “That’s the biggest thing we had to overcome,” said Sean Ressler, a postdoctoral researcher at UC Santa Barbara’s Kavli Institute for Theoretical Physics (KITP), who just published a paper in The Astrophysical Journal Letters, investigating the magnetic properties of the accretion disk surrounding Sagittarius A*.

    In the study, Ressler, fellow KITP postdoc Chris White and their colleagues, Eliot Quataert of UC Berkeley and James Stone at the Institute for Advanced Study, sought to determine whether the black hole’s magnetic field, which is generated by in-falling matter, can build up to the point where it briefly chokes off this flow, a condition scientists call magnetically arrested. Answering this would require simulating the system all the way out to the closest orbiting stars.

    The system in question spans seven orders of magnitude. The black hole’s event horizon, or envelope of no return, reaches around 4 to 8 million miles from its center. Meanwhile, the stars orbit around 20 trillion miles away, or about as far as the sun’s nearest neighboring star.

    “So you have to track the matter falling in from this very large scale all the way down to this very small scale,” said Ressler. “And doing that in a single simulation is incredibly challenging, to the point that it’s impossible.” The smallest events proceed on timescales of seconds while the largest phenomena play out over thousands of years.

    This paper connects small scale simulations, which are mostly theory-based, with large-scale simulations that can be constrained by actual observations. To achieve this, Ressler divided the task between models at three overlapping scales.

    The first simulation relied on data from Sagittarius A*’s surrounding stars.

    Star S0-2 Andrea Ghez Keck/UCLA Galactic Center Group at SGR A*, the supermassive black hole at the center of the milky way

    Fortunately, the black hole’s activity is dominated by just 30 or so Wolf-Rayet stars, which blow off tremendous amounts of material. “The mass loss from just one of the stars is larger than the total amount of stuff falling into the black hole during the same time,” Ressler said. The stars spend only around 100,000 years in this dynamic phase before transitioning into a more stable stage of life.

    The incredibly strong solar winds are visible in Ressler and White’s simulation of the Wolf-Rayet stars orbiting Sagittarius A*.
    Credit: SEAN RESSLER AND CHRIS WHITE

    Using observational data, Ressler simulated the orbits of these stars over the course of about a thousand years. He then used the results as the starting point for a simulation of medium-range distances, which evolve over shorter time scales. He repeated this for a simulation down to the very edge of the event horizon, where activity takes place in matters of seconds. Rather than stitching together hard overlaps, this approach allowed Ressler to fade the results of the three simulations into one another.

    “These are really the first models of the accretion at the smallest scales in [Sagittarius] A* that take into account the reality of the supply of matter coming from orbiting stars,” said coauthor White.

    And the technique worked splendidly. “It went beyond my expectations,” Ressler remarked.

    The results indicated that Sagittarius A* can become magnetically arrested. This came as a surprise to the team, since the Milky Way has a relatively quiet galactic center. Usually, magnetically arrested black holes have high-energy jets shooting particles away at relativistic speeds. But so far scientists have seen little evidence for jets around Sagittarius A*.

    “The other ingredient that helps create jets is a rapidly spinning black hole,” said White, “so this may be telling us something about the spin of Sagittarius A*.”

    Unfortunately, black hole spin is difficult to determine. Ressler modeled Sagittarius A* as a stationary object. “We don’t know anything about the spin,” he said. “There’s a possibility that it’s actually just not spinning.”

    Ressler and White next plan to model a spinning back hole, which is much more challenging. It immediately introduces a host of new variables, including spin rate, direction and tilt relative to the accretion disc. They will use data from the European Southern Observatory’s GRAVITY interferometer to guide these decisions.

    ESO GRAVITY in the VLTI

    2009 ESO VLTI Interferometer image, Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level, • ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).

    The team used the simulations to create images that can be compared to actual observations of the black hole. Scientists at the Event Horizon Telescope collaboration — which made headlines in April 2019 with the first direct image of a black hole — have already reached out requesting the simulation data in order to supplement their effort to photograph Sagittarius A*.

    The Event Horizon Telescope effectively takes a time average of its observations, which results in a blurry image. This was less of an issue when the observatory had their sights on Messier 87*, because it is around 1,000 times larger than Sagittarius A*, so it changes around 1,000 times more slowly.

    “It’s like taking a picture of a sloth versus taking a picture of a hummingbird,” Ressler explained. Their current and future results should help the consortium interpret their data on our own galactic center.

    Ressler’s results are a big step forward in our understanding of the activity at the center of the Milky Way. “This is the first time that Sagittarius A* has been modeled over such a large range in radii in 3D simulations, and the first event horizon-scale simulations to employ direct observations of the Wolf-Rayet stars,” Ressler said.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education CoalitionUC Santa Barbara Seal
    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
  • richardmitnick 11:51 am on June 9, 2020 Permalink | Reply
    Tags: "Mo'orea Coral Reef: Research in Paradise", Scientists are expanding our understanding of coral reef ecosystems and preparing the next generation of marine ecologists., UC Santa Barbara   

    From UC Santa Barbara: “Mo’orea Coral Reef: Research in Paradise” 

    UC Santa Barbara Name bloc
    From UC Santa Barbara

    With groundbreaking discoveries and innovative techniques in long-term ecological research, UC Santa Barbara is making waves at Gump Research Station, Mo’orea, where scientists are expanding our understanding of coral reef ecosystems and preparing the next generation of marine ecologists.

    1

    What is Gump Research Station?

    Situated on Cook’s Bay along the north shore of the island of Mo’orea, the University of California Gump Research Station is a premiere field station where scientists conduct critical research on the coral reefs and the many marine species that make their home in the warm waters of French Polynesia.

    Much of the work being done at Gump Research Station is led by UC Santa Barbara scientists, many of whom are seeking to understand how global change and other disturbances are impacting coral reef health. In 2004, the National Science Foundation established the Mo’orea Coral Reef Long Term Ecological Research (MCR LTER) site with ecology professors Sally Holbrook and Russ Schmitt as principal investigators.

    “These kinds of field stations are really the observatories for global change science and sustainability science”
    —Russ Schmitt, Ecology, Evolution and Marine Biology, UC Santa Barbara

    Long Term Ecological Research

    For three decades, ecologists Sally Holbrook and Russ Schmitt have been studying the coral reef complex that surrounds the island of Mo’orea, French Polynesia, seeking to understand what drives ecological change in natural systems. Specialists in population and community dynamics, they are co-principal investigators with the Mo’orea Coral Reef Long Term Ecological Research (MCR LTER) site.

    When in the field, MCR LTER researchers are based at the University of California Gump Research Station on Mo’orea. The field station gives scientists the unique opportunity to study the coral reefs surrounding Mo’orea in real time, contributing new knowledge while drawing from the trove of data that has been collected over 30 years. Together, they are working to find answers to some of the most pressing global questions of our time.

    “Coral reefs are one of the most diverse ecosystems on the planet.”
    —Deron Burkepile, Ecology, Evolution and Marine Biology, UC Santa Barbara

    Coral Reef Research

    Corals are marine invertebrates that live in communities of hundreds to thousands of identical, individual soft-bodied polyps. Each of these polyps secretes calcium carbonate, which collectively creates the hard outer skeleton that gives coral its familiar appearance. That skeletal structure provides a habitat for a host of other species, including fish and other invertebrates.

    Coral reefs support more species per unit area than any other marine environment, and that makes them key to the health of the planet. They occupy much less than 1% of all marine habitat, but are home to as much as a third of all marine species.

    In addition, coral reefs are critical to the millions of people who depend on them for food or as a means of livelihood through fishing and tourism, and to those who count on them as physical barriers that protect shorelines from damage caused by currents, waves and tropical storms.

    Much of the research conducted at Gump Research Station examines the resilience of Mo’orea’s coral reef systems and their resident species in the face of disturbances such as ocean temperature spikes.

    “It’s one of the most amazing experiences.”
    —Nury Molina, Ph.D. student, Ecology, Evolution & Marine Biology, UC Santa Barbara

    Graduate Student Experience

    Graduate student are conducting research on coral reefs that ranges from how herbivory controls algae that compete with corals to whether and how well fish adapt to rising sea water temperatures. All are making major contributions to our understanding of coral reef ecosystems and how they are responding to the impacts of global change and human activity.

    For some, Gump Research Station is not their first field station experience, but it’s the most valuable.

    “Having independence as a grad student has made me think about my own interests and pursue my own research projects, and that is really important for me moving forward in my career. And a big part of that is the opportunity to mentor undergraduate students.” — Kelly Speare, Ph.D. student.

    “I can’t imagine a better set-up for conducting research in the middle of the Pacific Ocean.” — Kai Kopecki, Ph.D. student in the Department of Ecology, Evolution and Marine Biology, UC Santa Barbara

    “The collaboration and energy of Gump Research Station is why I love coming back here. Everybody is helping each other out, and everyone is really interested in what others are working on. We all have the common goal of trying to understand what’s going on out here.”

    — Jordan Gallagher, master’s student in the Department of Ecology, Evolution and Marine Biology, UC Santa Barbara

    Undergraduate Student Experience

    It’s life changing — spending a summer at a field station on the island of Mo’orea in French Polynesia, contributing to real-time scientific research. The work is hard, the days are long and the friendships are everlasting.

    At Gump Research Station, undergraduates have the opportunity to bring the knowledge they have gained in the classroom and in campus labs to a real-world environment. Some find their passion in field work and expedition science, others discover it’s not for them and set career paths that take them in other directions. Either way, the educational value is immeasurable.

    3
    The view from the Belvedere, Mo’orea, French Polynesia. To the right is Cook’s Bay, where Gump Research Station is located. To the left is Ōpūnahu Bay.

    Community Outreach

    Environmental research that expands our understanding of the coral reef ecosystems around Mo’orea is the primary function of Mo’orea Coral Reef Long Term Ecological Research initiatives, but the scientists who work there also are keen to share their knowledge with school children — both in Mo’orea and in California — to nurture their budding scientific curiosity.

    They also welcome opportunities such as Earth Day and World Oceans Day to share their research — and enthusiasm — with the public.

    “The wisdom of the University of California to invest in field stations like the Gump Research Station is absolutely key, because without them, research programs to understand long-term changes to our ecosystem are not possible.” —Russ Schmitt, Ecology, Evolution and Marine Biology, UC Santa Barbara

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education CoalitionUC Santa Barbara Seal
    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
  • richardmitnick 11:20 am on May 12, 2020 Permalink | Reply
    Tags: "The Great Unconformity", , , UC Santa Barbara   

    From UC Santa Barbara: “The Great Unconformity” 

    UC Santa Barbara Name bloc
    From UC Santa Barbara

    May 7, 2020
    Harrison Tasoff
    (805) 893-7220
    harrisontasoff@ucsb.edu

    A billion years is missing from the geologic record; one UC Santa Barbara scientist believes he knows where it may have gone.

    1
    Francis Macdonald walks along a road near Manitou Springs, Colorado, where an exposed outcrop shows a feature known as the “Great Unconformity.”

    2
    Francis Macdonald. Photo Credit: UC Santa Barbara

    The geologic record is exactly that: a record. The strata of rock tell scientists about past environments, much like pages in an encyclopedia. Except this reference book has more pages missing than it has remaining. So geologists are tasked not only with understanding what is there, but also with figuring out what’s not, and where it went.

    One omission in particular has puzzled scientists for well over a century. First noticed by John Wesley Powell in 1869 in the layers of the Grand Canyon, the Great Unconformity, as it’s known, accounts for more than one billion years of missing rock in certain places.

    Scientists have developed several hypotheses to explain how, and when, this staggering amount of material may have been eroded. Now, UC Santa Barbara geologist Francis Macdonald and his colleagues at the University of Colorado, Boulder and at Colorado College believe they may have ruled out one of the more popular of these. Their study appears in the Proceedings of the National Academy of Sciences.

    “There are unconformities all through the rock record,” explained Macdonald, a professor in the Department of Earth Science. “Unconformities are just gaps in time within the rock record. This one’s called the Great Unconformity because it was thought to be a particularly large gap, maybe a global gap.”

    A leading thought is that glaciers scoured away kilometers of rock around 720 to 635 million years ago, during a time known as Snowball Earth, when the planet was completely covered by ice. This hypothesis even has the benefit of helping to explain the rapid emergence of complex organisms shortly thereafter, in the Cambrian explosion, since all this eroded material could have seeded the oceans with tremendous amounts of nutrients.

    Macdonald was skeptical of this reasoning. Although analogues of the Great Unconformity appear throughout the world — with similar amounts of rock missing from similar stretches of time — they don’t line up perfectly. This casts doubt as to whether they were truly eroded by a global event like Snowball Earth.

    Part of the challenge of investigating the Great Unconformity is that it happened so long ago, and the Earth is a messy system. “These rocks have been buried and eroded multiple times through their history,” Macdonald said.

    Fortunately, the team was able to test this hypothesis using a technique called thermochronology. A few kilometers below the Earth’s surface, the temperature begins to rise as you get closer to the planet’s hot mantle. This creates a temperature gradient of roughly 35 degrees Celsius for every kilometer of depth. And this temperature regime can become imprinted in certain minerals.

    As certain radioactive elements in rocks break down, Helium-4 is produced. In fact helium is constantly being generated, but the fraction retained in different minerals is a function of temperature. As a result, scientists can use the ratio of helium to thorium and uranium in certain minerals as a paleo-thermometer. This phenomenon enabled Macdonald and his coauthors to track how rock moved in the crust as it was buried and eroded through the ages.

    “These unconformities are forming again and again through tectonic processes,” Macdonald said. “What’s really new is we can now access this much older history.”

    The team took samples from granite just below the boundary of the Great Unconformity at Pikes Peak in Colorado. They extracted grains of a particularly resilient mineral, zircon, from the stone and analyzed the radio nucleotides of helium contained inside. The technique revealed that several kilometers of rock had been eroded from above this granite between 1,000 and 720 million years ago.

    3
    Zircons from Pikes Peak. Photo Credit: FRANCIS MACDONALD

    Importantly, this stretch of time definitively came before the Snowball Earth episodes. In fact, it lines up much better with the periods in which the supercontinent Rodinia was forming and breaking apart. This offers a clue to the processes that may have stricken these years from the geologic record.

    “The basic hypothesis is that this large-scale erosion was driven by the formation and separation of supercontinents,” Macdonald said.

    The Earth’s cycle of supercontinent formation and separation uplifts and erodes incredible extents of rock over long periods of time. And because supercontinent processes, by definition, involve a lot of land, their effects can appear fairly synchronous across the geologic record.

    However, these processes don’t happen simultaneously, as they would in a global event like Snowball Earth. “It’s a messy process,” Macdonald said. “There are differences, and now we have the ability to perhaps resolve those differences and pull that record out.”

    While Macdonald’s results are consistent with a tectonic origin for these great unconformities, they don’t end the debate. Geologists will need to complement this work with similar studies in other regions of the world in order to better constrain these events.

    The mystery of the Great Unconformity is inherently tied to two of geology’s other great enigmas: the rise and fall of Snowball Earth and the sudden emergence of complex life in the Ediacaran and Cambrian. Progress in any one could help researchers finally crack the lot.

    “The Cambrian explosion was Darwin’s dilemma,” Macdonald remarked. “This is a 200-year old question. If we can solve that, we would definitely be rock stars.”

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education CoalitionUC Santa Barbara Seal
    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
  • richardmitnick 11:22 am on April 1, 2020 Permalink | Reply
    Tags: "Scientists Are Stuck on an Ice-Locked Ship in the Arctic Due to Coronavirus", MOSAiC expedition, , UC Santa Barbara,   

    From UC Santa Barbara via Vice: “Scientists Are Stuck on an Ice-Locked Ship in the Arctic Due to Coronavirus” 

    UC Santa Barbara Name bloc
    From UC Santa Barbara

    via

    1
    Vice

    Mar 27 2020
    Maddie Stone

    Organizers of the MOSAiC expedition are determining the best way to bring a relief crew to the ship without spreading the virus, which could leave roughly 100 scientists and crew on board for an extra six weeks.

    2
    Polarstern. Image: Sebastian Grote

    For the past six months, the German icebreaker Polarstern has been drifting through the central Arctic Ocean, intentionally frozen into the ice. A rotating cast of hundreds of scientists from all over the world have been traveling to and from the vessel for months at a time to assist with the MOSAiC expedition, an enormous polar science effort aimed at improving our understanding of the Arctic environment in a time of rapid, human-caused climate change.

    The year-long expedition’s next crew rotation was set to fly to the Polarstern from Svalbard, Norway, in mid-April. But thanks to a global pandemic, that plan has been dashed. Now, the scientists currently aboard the Polarstern are preparing to stay put for approximately six weeks longer than they had planned in order to keep the ship’s myriad research projects alive.

    Earlier this month, the government of Svalbard—a remote island archipelago in the Arctic Ocean—closed its borders to outsiders amid growing concerns over Covid-19. As a result, roughly 100 scientists and support staff who had planned to relieve the crew that’s been aboard the Polarstern since February no longer have a flight. MOSAiC’s organizers are now scrambling to pull together a contingency plan, which will likely involve ferrying the next group of scientists north with a resupply shipment aboard a giant icebreaker vessel.

    “There’s no way to carry out these flights for the crew rotation,” said Markus Rex, an atmospheric scientist at the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research and expedition leader for MOSAiC. “That has a major impact on how we plan the expedition.”

    As the coronavirus pandemic ripples around the globe, travel by air, land, and sea has been brought to a standstill. This is upending countless scientific field expeditions, including planned trips to Greenland this spring, NASA-led Earth science airborne campaigns, and dozens of oceanographic research cruises using ships that are part of the U.S. Academic Research Fleet, which was ordered to stand down earlier this month.

    MOSAiC scientists face the challenge of continuing a massive international research endeavor that can’t easily be stopped. As organizers navigate travel restrictions in order to keep crews of scientists and support staff rotating on and off the Polarstern and ensure a steady influx of new supplies, they’re also doing everything in their power to prevent a deadly virus from spreading to the vessel, which is difficult to reach by air and takes weeks to reach by sea.

    The first signs of trouble came earlier this month, when a researcher who had planned to participate in survey flights out of Svalbard to support MOSAiC tested positive for the virus. That caused MOSAiC to delay its spring airborne campaign, and subsequently, the campaign was canceled as the Norweigan government and local authorities on Svalbard began restricting international travel.The MOSAiC team is exploring the possibility of extending a series of planned summertime flights to compensate, although Rex warned that it’s “too early to say what will happen to the summer phase.”

    The cancellation of these survey flights, which were going to study Arctic ice, cloud, and aerosol properties, are a disappointment, but they don’t compromise the campaign’s core scientific mission.

    The bigger concern now is what to do about the crew that was supposed to link up with the Polarstern in April, relieving the roughly 100 scientists and support staff currently aboard. Fortunately, the Polarstern is in no danger of running out of supplies anytime soon, and the scientists currently on board are continuing to go about their day-to-day activities.

    “People on Polarstern are safe, they are in a virus free environment, they have all the provisions they need,” Rex said. “They are focusing on science.”

    The contingency plan now taking shape involves chartering an icebreaker vessel to ferry the relief crew north after everyone’s undergone a 14-day quarantine and tested negative for the coronavirus. Organizers are currently in talks with “a number of icebreakers,” Rex said, as well as authorities in various partner countries to determine where their vessel can ship off from.

    Or, instead of chartering an entirely new ship, the team could potentially accelerate the expedition’s next resupply cruise. MOSAiC had already chartered the Swedish icebreaker Oden to ship north and rendezvous with the Polarstern in June. Organizers are now looking into the possibility of bumping that resupply shipment forward to approximately mid-May, and sending the relief crew along with it. In that scenario, the team currently aboard Polarstern would spend about six extra weeks on the ship, and instead of three more crew changes between now and September, there would be two.

    While this would mean leaving behind some scientists who had planned to participate in MOSAiC, Rex says it’s likely that a number of researchers will not be able to go anyway due to travel restrictions from their institutions or countries.

    Another challenge MOSAiC’s organizers have been wrestling with is disembarking an outgoing expedition of scientists who left the Polarstern in early March bound for Tromso, Norway. Until very recently, it looked as if these researchers—traveling aboard the Russian icebreaker Kapitan Dranitsyn—would need to find a new port due to Norway’s coronavirus travel restrictions. But recently, the team got some good news: The Norweigan authorities are granting the Kapitan Dranitsyn an exception so that its crew can disembark and head to a nearby airport.

    “We will bring them from a bus transport from the port to a shuttle flight back to Germany,” Rex said. “And we have support from the German authorities to travel to Bremen and back to their home countries from Bremen. Obviously that was quite a bit of work to make that happen.”

    As the MOSAiC mission soldiers on, other scientists are coming to terms with the fact that their own expeditions, some of which have been in the works for years, are going to have to wait as well.

    These include a University of Rhode Island-led campaign to study symbiotic relationships between deep sea animals and bacteria at hydrothermal vents in the southwest Pacific in April, and EXPORTS, a NASA-led effort to study ocean carbon cycling that includes over a dozen research projects and was set to kick off next month in the North Atlantic.

    Both cruises were called off earlier this month amidst the U.S. Academic Research Fleet’s 30-day suspension, and both are now anticipating significant delays.

    “We don’t know when this cruise will be rescheduled,” said Roxanne Beinart, an assistant professor at the University of Rhode Island leading the deep sea campaign, noting that it took several years for her team to secure both the vessel and underwater robots needed to carry out their planned field work. “Even if the pandemic miraculously resolves very quickly, it could be easily a year before we get back on the schedule.”

    As for EXPORTS, it’s currently unclear whether it can be resuscitated in the exact manner as was planned for this year, partly because one of the participating research vessels, the R/V Atlantis, wasn’t scheduled to be in the Atlantic in 2021. Science lead Dave Siegel of the University of California, Santa Barbara said the team has reached out to various European partners to see if a different ship can be secured. But ultimately, some science might have to be sacrificed for the sake of expediency, since a key goal of the campaign was to provide data in support of an $800-million NASA ocean satellite slated to launch in 2022.

    “Science is going to go forward,” Siegel said, noting that an initial 2018 campaign in the North Pacific was quite successful. “But having the opportunity to get all the resources in the same place at the same time? I don’t know if we’ll be able to do that again.”

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education CoalitionUC Santa Barbara Seal
    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
  • richardmitnick 12:23 pm on March 12, 2020 Permalink | Reply
    Tags: "On the Hunt for Gravitons", , Investigating gravity interacting with electromagnetism from a quantum field theory perspective., , Physics has two superb theories explaining our universe. The problem is no one can join them together., Results deemed to be correct but too small for experimental confirmation — ever., UC Santa Barbara   

    From UC Santa Barbara: “On the Hunt for Gravitons” 

    UC Santa Barbara Name bloc
    From UC Santa Barbara

    March 10, 2020
    Harrison Tasoff
    (805) 893-7220
    harrisontasoff@ucsb.edu

    1
    Gravitational waves from merging neutron stars visualized as a surge of discrete particles, called gravitons.
    Photo Credit: R. Hurt – Caltech / JPL.

    Physics has two superb theories explaining our universe. The problem is no one can join them together.

    Einstein’s general relativity describes how physics plays out on the scale of the universe, with gravity as the main actor. Meanwhile, quantum mechanics and the standard model make detailed predictions about the processes at the subatomic scale — predictions that have been verified billions of times in massive particle colliders and detectors.

    Unfortunately, the two don’t mesh very well. One consequence of that: while scientists know of particles associated with the strong, weak and electromagnetic forces, they have yet to discover a particle of gravity, or graviton.

    UC Santa Barbara physics professor Ray Sawyer has published a paper in Physical Review Letters investigating gravity interacting with electromagnetism from a quantum field theory perspective. The study suggests new directions to explore for clues about how gravity works at the quantum scale, focusing on the behavior of the dense cloud of gravitons that appears near a violent event in space, such as a black hole merger. Some of the gravitons can then transform themselves into very long wave radio waves of possible detectability in the vicinity of Earth.

    The article is featured as an Editors’ Selection on the journal’s web-page.

    “The most important result is the possibility of verifying the quantum nature of the gravitational field,” said Sawyer. “And that is so significant that you probably don’t want to dilute the message with other, subsidiary stuff.

    “One reason that question has become of particular interest is that a small but apparently growing fringe of persons are questioning whether gravitons should exist,” he continued. “This is a result of frustration over unresolved technical issues in quantum general relativity that have extended over generations. I duck these issues by using some classic results from a calculable sector of the theory, results that had been deemed to be correct but too small for experimental confirmation — ever. And my innovations were strictly in the domain of applying these classic results to systems of vast numbers of simultaneously interacting acting gravitons, rather than to two gravitons interacting to form two photons.“

    Sawyer describes two advances that made his results possible. The first was uncovering a “mean-field instability” in the governing equations. The second was adapting “quantum break” theory, already in use for some localized condensed-matter systems containing scores of atoms in a “Bose Condensate” state. He emphasized that neither step required proficiency in the general theory of relativity. Sawyer also acknowledged his deep debt to the quantum general relativists who in 1975 provided the real basis for the current work.

    Sawyer is a founding member of UC Santa Barbara’s Kavli Institute for Theoretical Physics, which began in 1979.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education CoalitionUC Santa Barbara Seal
    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
  • richardmitnick 12:38 pm on November 21, 2019 Permalink | Reply
    Tags: "A Marvelous Molecular Machine", A finely tuned molecular process in the camouflage of certain squid may lead to the next generation of bio-inspired synthetic materials., , , , , UC Santa Barbara   

    From UC Santa Barbara: “A Marvelous Molecular Machine” 

    UC Santa Barbara Name bloc
    From UC Santa Barbara

    November 15, 2019
    Harrison Tasoff
    Sonia Fernandez
    (805) 893-4765
    sonia.fernandez@ucsb.edu

    “A Marvelous Molecular Machine”

    A finely tuned molecular process in the camouflage of certain squid may lead to the next generation of bio-inspired synthetic materials.

    1
    The adaptive iridocytes in the skin of the California market squid are able tune color through most of the spectrum.

    Squids, octopuses and cuttlefish are undisputed masters of deception and camouflage. Their extraordinary ability to change color, texture and shape is unrivaled, even by modern technology.

    Researchers in the lab of UC Santa Barbara professor Daniel Morse have long been interested in the optical properties of color-changing animals, and they are particularly intrigued by the opalescent inshore squid. Also known as the California market squid, these animals have evolved the ability to finely and continuously tune their color and sheen to a degree unrivaled in other creatures. This enables them to communicate, as well as hide in plain sight in the bright and often featureless upper ocean.

    In previous work, the researchers uncovered that specialized proteins, called reflectins, control reflective pigment cells — iridocytes — which in turn contribute to changing the overall visibility and appearance of the creature. But still a mystery was how the reflectins actually worked.

    “We wanted now to understand how this remarkable molecular machine works,” said Morse, a Distinguished Emeritus Professor in the Department of Molecular, Cellular and Developmental Biology, and principal author of a paper that appears in the Journal of Biological Chemistry. Understanding this mechanism, he said, would provide insight into the tunable control of emergent properties, which could open the door to the next generation of bio-inspired synthetic materials.

    Light-reflecting skin

    Like most cephalopods, opalescent inshore squid, practice their sorcery by way of what may be the most sophisticated skin found anywhere in nature. Tiny muscles manipulate the skin texture while pigments and iridescent cells affect its appearance. One group of cells controls their color by expanding and contracting cells in their skin that contain sacks of pigment.

    Behind these pigment cells are a layer of iridescent cells — those iridocytes — that reflect light and contribute to the animals’ color across the entire visible spectrum. The squids also have leucophores, which control the reflectance of white light. Together, these layers of pigment-containing and light-reflecting cells give the squids the ability to control the brightness, color and hue of their skin over a remarkably broad palette.

    Unlike the color from pigments, the highly dynamic hues of the opalescent inshore squid result from changing the iridocyte’s structure itself. Light bounces between nanometer-sized features about the same size as wavelengths in the visible part of the spectrum, producing colors. As these structures change their dimensions, the colors change. Reflectin proteins are behind these features’ ability to shapeshift, and the researchers’ task was to figure out how they do the job.

    Thanks to a combination of genetic engineering and biophysical analyses, the scientists found the answer, and it turned out to be a mechanism far more elegant and powerful than previously imagined.

    “The results were very surprising,” said first author Robert Levenson, a postdoctoral researcher in Morse’s lab. The group had expected to find one or two spots on the protein that controlled its activity, he said. “Instead, our evidence showed that the features of the reflectins that control its signal detection and the resulting assembly are spread across the entire protein chain.”

    An Osmotic Motor

    Reflectin, which is contained in closely packed layers of membrane in iridocytes, looks a bit like a series of beads on a string, the researchers found. Normally, the links between the beads are strongly positively charged, so they repel each other, straightening out the proteins like uncooked spaghetti.

    Morse and his team discovered that nerve signals to the reflective cells trigger the addition of phosphate groups to the links. These negatively charged phosphate groups neutralize the links’ repulsion, allowing the proteins to fold up. The team was especially excited to discover that this folding exposed new, sticky surfaces on the bead-like portions of the reflectin, allowing them to clump together. Up to four phosphates can bind to each reflectin protein, providing the squid with a precisely tunable process: The more phosphates added, the more the proteins fold up, progressively exposing more of the emergent hydrophobic surfaces, and the larger the clumps grow.

    As these clumps grow, the many, single, small proteins in solution become fewer, larger groups of multiple proteins. This changes the fluid pressure inside the membrane stacks, driving water out — a type of “osmotic motor” that responds to the slightest changes in charge generated by the neurons, to which patches of thousands of leucophores and iridocytes are connected. The resulting dehydration reduces the thickness and spacing of the membrane stacks, which shifts the wavelength of reflected light progressively from red to yellow, then to green and finally blue. The more concentrated solution also has a higher refractive index, which increases the cells’ brightness.

    “We had no idea that the mechanism we would discover would turn out to be so remarkably complex yet contained and so elegantly integrated in one multifunctional molecule — the block-copolymeric reflectin — with opposing domains so delicately poised that they act like a metastable machine, continually sensing and responding to neuronal signaling by precisely adjusting the osmotic pressure of an intracellular nanostructure to precisely fine-tune the color and brightness of its reflected light,” Morse said.

    What’s more, the researchers found, the whole process is reversible and cyclable, enabling the squid to continually fine-tune whatever optical properties its situation calls for.

    New Design Principles

    The researchers had successfully manipulated reflectin in previous experiments, but this study marks the first demonstration of the underlying mechanism. Now it could provide new ideas to scientists and engineers designing materials with tunable properties. “Our findings reveal a fundamental link between the properties of biomolecular materials produced in living systems and the highly engineered synthetic polymers that are now being developed at the frontiers of industry and technology,” Morse said.

    “Because reflectin works to control osmotic pressure, I can envision applications for novel means of energy storage and conversion, pharmaceutical and industrial applications involving viscosity and other liquid properties, and medical applications,” he added.

    Remarkably, some of the processes at work in these reflectin proteins are shared by the proteins that assemble pathologically in Alzheimer’s disease and other degenerative conditions, Morse observed. He plans to investigate why this mechanism is reversible, cyclable, harmless and useful in the case of reflectin, but irreversible and pathological for other proteins. Perhaps the fine-structured differences in their sequences can explain the disparity, and even point to new paths for disease prevention and treatment.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education CoalitionUC Santa Barbara Seal
    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
  • richardmitnick 12:22 pm on November 14, 2019 Permalink | Reply
    Tags: "Tomorrow’s Data Centers", , , Bringing the speed high data capacity and low-energy use of light (optics) to advanced internet infrastructure architecture., , The amount of worldwide data traffic is driving up the capacity inside data centers to unprecedented levels and today’s engineering solutions break down., The deluge of data we transmit across the globe via the internet-enabled devices and services that come online every day has required us to become much more efficient., The keys according to Blumenthal are to shorten the distance between optics and electronics., This challenge is a now job for Blumenthal’s FRESCO: FREquency Stabilized COherent Optical Low-Energy Wavelength Division Multiplexing DC Interconnects., UC Santa Barbara, While still in early stages the FRESCO team’s technology is very promising.   

    From UC Santa Barbara: “Tomorrow’s Data Centers” 

    UC Santa Barbara Name bloc
    From UC Santa Barbara

    November 12, 2019
    Sonia Fernandez

    1
    The deluge of data we transmit across the globe via the internet-enabled devices and services that come online every day has required us to become much more efficient with the power, bandwidth and physical space needed to maintain the technology of our modern online lives and businesses.

    2
    L to r: Electrical and computer engineering professor Dan Blumenthal, and doctoral student researchers Grant Brodnik and Mark Harrington
    Photo Credit: Sonia Fernandez

    “Much of the world today is interconnected and relies on data centers for everything from business to financial to social interactions,” said Daniel Blumenthal, a professor of electrical and computer engineering at UC Santa Barbara. The amount of data now being processed is growing so fast that the power needed just to get it from one place to another along the so-called information superhighway constitutes a significant portion of the world’s total energy consumption, he said. This is particularly true of interconnects — the part of the internet infrastructure tasked with getting data from one location to another.

    “Think of interconnects as the highways and the roads that move data,” Blumenthal said. There are several levels of interconnects, from the local types that move data from one device on a circuit to the next, to versions that are responsible for linkages between data centers. The energy required to power interconnects alone is 10% of the world’s total energy consumption and climbing, thanks to the growing amount of data that these components need to turn from electronic signals to light, and back to electronic signals. The energy needed to keep the data servers cool also adds to total power consumption.

    “The amount of worldwide data traffic is driving up the capacity inside data centers to unprecedented levels and today’s engineering solutions break down,” Blumenthal explained. “Using conventional methods as this capacity explodes places a tax on the energy and cost requirements of physical equipment, so we need drastically new approaches.”

    As the demand for additional infrastructure to maintain the performance of the superhighway increases, the physical space needed for all these components and data centers is becoming a limiting factor, creating bottlenecks of information flow even as data processing chipsets increase their capacity to a whopping 100 terabytes per second.

    “The challenge we have is to ramp up for when that happens,” said Blumenthal, who also serves as director for UC Santa Barbara’s Terabit Optical Ethernet Center, and represents UC Santa Barbara in Microsoft’s Optics for the Cloud Research Alliance.

    This challenge is a now job for Blumenthal’s FRESCO: FREquency Stabilized COherent Optical Low-Energy Wavelength Division Multiplexing DC Interconnects. Bringing the speed, high data capacity and low-energy use of light (optics) to advanced internet infrastructure architecture, the FRESCO team aims to solve the data center bottleneck while bringing energy usage and space needs to a more sustainable level.

    The effort is funded by ARPA-e under the OPEN 2018 program and represents an important industry-university partnership with emphasis on technology transition. The FRESCO project involves important industry partners like Microsoft and Barefoot Networks (now Intel), who are looking to transition new technologies to solve the problems of exploding chip and data center capacities.

    The keys, according to Blumenthal, are to shorten the distance between optics and electronics, while also drastically increasing the efficiency of maintaining the synchrony of the optical signal between the transmitting and receiving end of the interconnect.

    FRESCO can accomplish this by bringing the performance of optical technology — currently relegated to long-haul transmission via fiberoptic cable — to the chip and co-locating both optic and electronic components on the same switch chip.

    “The way FRESCO is able to do this is by bringing to bear techniques from large-scale physics experiments to the chip scale,” Blumenthal said. It’s a departure from the more conventional faceplate-and-plug technology, which requires signal to travel some distance to be converted before moving it along.

    From Big Physics to Small Chips

    Optical signals can be stacked in a technique known as coherent wave-division multiplexing (WDM), which allows signal to be sent over different frequencies — colors — over a single optical fiber. However, because of space constraints, Blumenthal said, the traditional measures used to process long-haul optical signals, including electronic digital signal processing (DSP) chips and very high bandwidth circuits, have to be removed from the interconnect links.

    FRESCO does away with these components with an elegant and powerful technique that “anchors” the light at both transmitting and receiving ends, creating spectrally pure stable light that Blumenthal has coined “quiet light.”

    “In order to do that we actually bring in light stabilization techniques and technologies that have been developed over the years for atomic clocks, precision metrology and gravitational wave detection, and use this stable, quiet light to solve the data center problem,” Blumenthal said. “Bringing key technologies from the big physics lab to the chip scale is the challenging and fun part of this work.”

    Specifically, he and his team have been using a phenomenon called stimulated Brillouin scattering, which is characterized by the interaction of light — photons — with sound produced inside the material through which it is traveling. These sound waves — phonons — are the result of the collective light-stimulated vibration of the material’s atoms, which act to buffer and quiet otherwise “noisy” light frequencies, creating a spectrally pure source at the transmitting and receiving ends. The second part of the solution is to anchor or stabilize these pure light sources using optical cavities that store energy with such high quality that the lasers are anchored in a way that allows them to be aligned using low-energy electronic circuits used in the radio world.

    The act of alignment requires that the light frequency and phase are kept equal so that data can be recovered. This normally requires high power analog electronics or high powered digital signal processors (DSPs), which are not viable solutions for bringing this capacity inside the data center (they have 100,000s of fiber connections in the data center, as compared to 10s of connections in the long-haul). Also, the more energy and space the technologies inside the data center take, an equal number or more get expended on the cooling of the data center.

    “There is very little energy needed to just keep them aligned and finding each other,” Blumenthal said of FRESCO, “similar to that of electronic circuits used for radio. “That is the exciting part — we are enabling a transmission carrier at 400 THz to carry data using low-energy simple electronic circuits, as opposed to the use of DSPs and high bandwidth circuitry, which in essence throws a lot of processing power at the optical signal to hunt down and match the frequency and phase of the optical signal so that data can be recovered.” With the FRESCO method, the lasers from the the transmitting and receiving ends are “anchored within each other’s sights in the first place, and drift very slowly on the order of minutes, requiring very little effort to track one with the other,” according to Blumenthal.

    On the Horizon, and Beyond

    While still in early stages, the FRESCO team’s technology is very promising. Having developed discrete components, the team is poised to demonstrate the concept by linking those components, measuring energy use, then transmitting the highest data capacity over a single frequency with the lowest energy to date on a frequency stabilized link. Future steps include demonstrating multiple frequencies using a technology called optical frequency combs that are integral to atomic clocks, astrophysics and other precision sciences. The team is in the process of integrating these components onto a single chip, ultimately aiming to develop manufacturing processes that will allow for transition to FRESCO technology.

    This technology is likely only the tip of the iceberg when it comes to possible innovations in the realm of optical telecommunications.

    “We see our chipset replacing over a data center link what today would take between four to 10 racks of equipment,” Blumenthal said. “The fundamental knowledge gained by developing this technology could easily enable applications we have yet to invent, for example in quantum communications and computing, precision metrology and precision timing and navigation.”

    “If you look at trends, over time you can see something that in the past took up a room full of equipment become something that was personally accessible through a technology innovation — for example supercomputers that became laptops through nanometer transistors,” he said of the disruption that became the wave in personal computing and everything that it enabled. “We know now how we want to apply the FRESCO technology to the data center scaling problem, but we think there also are going to be other unforeseen applications too. This is one of the primary reasons for research exploration and investment without knowing all the answers or applications beforehand.”

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education CoalitionUC Santa Barbara Seal
    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
  • richardmitnick 10:45 am on May 13, 2019 Permalink | Reply
    Tags: "Researchers Just Tested a Prototype Probe Designed to 'Sail' Between The Stars", , Directed-energy light sail and a wafer-scale spacecraft (WSS), , UC Santa Barbara, UCSB Experimental Cosmology Group (ECG)   

    From UC Santa Barbara via Science Alert: “Researchers Just Tested a Prototype Probe Designed to ‘Sail’ Between The Stars” 

    UC Santa Barbara Name bloc
    From UC Santa Barbara

    via

    ScienceAlert

    Science Alert

    13 MAY 2019
    MATT WILLIAMS

    1
    UCSB

    At the University of California, Santa Barbara, researchers with the UCSB Experimental Cosmology Group (ECG) are currently working on ways to achieve the dream of interstellar flight.

    Under the leadership of Philip Lubin, the group has dedicated a considerable amount of effort towards the creation of an interstellar mission consisting of directed-energy light sail and a wafer-scale spacecraft (WSS) “wafercraft“.

    If all goes well, this spacecraft will be able to reach relativistic speeds (a portion of the speed of light) and make it to the nearest star system (Proxima Centauri) within our lifetimes.

    Recently, the ECG achieved a major milestone by successfully testing a prototype version of their wafercraft (aka. the “StarChip”). This consisted of sending the prototype via balloon into the stratosphere to test its functionality and performance.

    The launch was conducted in collaboration with the United States Naval Academy in Annapolis on April 12, 2019. This date was selected to coincide with the 58th anniversary of Russian Cosmonaut Yuri Gagarin’s orbital space flight, making him the first human to go to space.

    The test consisted of launching the prototype aboard a balloon to an altitude of 32,000 metres (105,000 feet) above Pennsylvania.

    As Lubin explained in an interview with UCSB’s The Current:

    “It’s part of a process of building for the future, and along the way you test each part of the system to refine it. It’s part of a long-term program to develop miniature spacecraft for interplanetary and eventually for interstellar flight.”

    The idea behind the StarChip is simple. By taking advantage of advancements in miniaturization, all the necessary components of an exploratory mission could be mounted on a spacecraft the size of a human hand.

    The sail component builds on the concept of a solar sail and developments made with lightweight materials; and together, they add up to a spacecraft that could be accelerated up to 20 percent the speed of light.

    For the sake of this flight, the science team that created it put the StarChip through a series of tests designed to gauge its performance in space and ability to explore other worlds.

    Aside from seeing how it faired in Earth’s stratosphere (three times higher than the operational ceiling of airplanes), the prototype collected more than 4000 images of the Earth.

    As Nic Rupert, a development engineer in Lubin’s lab, explained:

    “It was designed to have many of the functions of much larger spacecraft, such as imaging, data transmission, including laser communications, attitude determination and magnetic field sensing. Due to the rapid advancements in microelectronics we can shrink a spacecraft into a much smaller format than has been done before for specialized applications such as ours.”

    3
    Prototype StarChip tested by the UCSB Experimental Cosmology Group. (UCSB)

    While the StarChip performed flawlessly on this flight, there are some massive technical hurdles ahead.

    Considering the distances involved – 4.24 light years (40 trillion kilometres; 25 trillion miles) – and the fact that the spacecraft will need to reach a fraction of the speed of light, the technological requirements are daunting.

    As Lubin said:

    “Ordinary chemical propulsion, such as that which took us to the Moon nearly 50 years ago to the day, would take nearly one hundred thousand years to get to the nearest star system, Alpha Centauri. And even advanced propulsion such as ion engines would take many thousands of years. There is only one known technology that is able to reach the nearby stars within a human lifetime and that is using light itself as the propulsion system.”

    One of the greatest challenges at this point is building an Earth-based laser array that would be capable of accelerated the laser sail.

    “If you have a large enough laser array, you can actually push the wafers with a laser sail to get to our goal of 20 percent of the speed of light,” added Rupert. “Then you’d be at Alpha Centauri in something like 20 years.”

    Since 2009, the UCSB Experimental Cosmology Group has been researching and developing this concept as part of a NASA Advanced Concepts program called Starlight.

    Since 2016, they have received considerable support from Breakthrough Initiatives (the non-profit space exploration program created by Yuri Milner) as part of Breakthrough Starshot.

    Solar sail. Breakthrough Starshot image. Credit: Breakthrough Starshot

    Rather than creating a single spacecraft, the team hopes that their research will lead to the creation of hundreds and even thousands of waferscale craft that could visit exoplanets in nearby star systems.

    These spacecraft would do away with the need for propellant and would be able to make the journey within a few decades rather than centuries or millennia.

    In this respect, these spacecraft would be able to reveal whether or not life exists beyond Earth in our lifetimes. Another interesting aspect of the UCSB project involves sending life from Earth to other exoplanets.

    Specifically, tardigrades and the nematode C. elegans, two species that have been shown to be highly resistant to radiation, capable of handling the conditions of space, and capable of being cryogenically frozen and revived.

    This aspect of their plan is not unlike the proposal made by Claudius Gros of Goethe University’s Institute for Theoretical Physics.

    Appropriately named “Project Genesis,” the proposal calls for spacecraft propelled by directed energy to travel to other star systems and seed any “transiently habitable” exoplanets that are there.

    In short, life would be given a jumpstart on planets that are habitable but not inhabited.

    As David McCarthy, a graduate student in the Department of Electrical and Computer Engineering at UCSB, explained, getting to the point where all is possible is a very iterative process.

    “The point of building these things is to know what we want to include in the next version, in the next chip,” he said. “You start with off-the-shelf components because you can iterate quickly and inexpensively.”

    With this high-altitude test complete, the UCSB group is aiming for a suborbital first flight next year. Meanwhile, advances in silicon optics and integrated wafer-scale photonics – thanks in part to research being conducted by UCSB’s electrical and computer engineering department – are reducing the cost of mass-producing these tiny spacecraft.

    In addition to interstellar travel, this technology could facilitate rapid, low-cost missions to Mars and other locations in the Solar System.

    Lubin and his fellow researchers have also spent years exploring applications for planetary defense against comets, mitigating space debris, boosting Earth-orbiting satellites, or remotely powering distant Solar System outposts.

    When it comes to directed energy, the possibilities really are staggering.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Santa Barbara Seal
    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
  • richardmitnick 11:28 am on April 30, 2019 Permalink | Reply
    Tags: "Getting Hotter Underwater", A new study suggests that some species are feeling the heat more than others., , “New conservation efforts will be needed if the ocean is going to continue supporting human wellbeing nutrition and economic activity” said lead author Malin Pinsky associate professor at Rutgers , “There’s no such thing as a cool shady spot under the sea, Between 1996 and 2014 New York’s registered lobster landings decreased by 97.7%, , Ecosystems are in flux as rising temperatures affect where animals can live and how they behave., Global warming harms ocean life worse than it does on land”, Local extinctions are currently proceeding at twice the rate in the ocean as on land., More species are living in the higher end of their temperature tolerances in the ocean than on land., UC Santa Barbara   

    From UC Santa Barbara: “Getting Hotter Underwater” 

    UC Santa Barbara Name bloc
    From UC Santa Barbara

    April 29, 2019
    Harrison Tasoff

    1
    Photo Credit: Ron McPeak

    Ecosystems are in flux as rising temperatures affect where animals can live and how they behave. And a new study suggests that some species are feeling the heat more than others.

    An international team of scientists including Douglas McCauley, an associate professor at UC Santa Barbara, has discovered that marine animals are especially vulnerable to rising temperatures. The results appear in the journal Nature.

    “We certainly did not discover for the first time that global warming harms for ocean life, but we did discover, arguably, that global warming harms ocean life worse than it does on land,” said McCauley, a marine ecologist in the Department of Ecology, Evolution, and Marine Biology and the university’s Marine Science Institute. “And that, actually, is pretty important to realize because it teaches us where to focus our energy when trying to remediate ecosystems and build out resiliency to climate impacts.”

    The team searched the literature for data on the range of survivable temperatures for 318 terrestrial and 88 marine species from 15 different classes of coldblooded animals, such as lizards, fish and spiders. They were curious what temperature range each animal could handle, and how close it was living to its thermal maximum. They also asked how the habitats in this safe temperature range will move as climate change progresses.

    Their key finding was that more species are living in the higher end of their temperature tolerances in the ocean than on land. This is likely early evidence of ocean warming, according to McCauley. “The species in the ocean appear to be much more sensitive to global warming as many are already sitting so close to the ceiling of the range of temperatures they can safely tolerate,” he said. This could explain why local extinctions are currently proceeding at twice the rate in the ocean as on land.

    In fact, by compiling data on some of the species’ historical ranges and comparing it to their current ranges, McCauley could actually see widespread population die-off in the warmer sub-regions. Take the American lobster for example. This iconic species is synonymous with New England, and historically it was commonly caught in states like New York. But the lobster populations there have dropped precipitously. Between 1996 and 2014 New York’s registered lobster landings decreased by 97.7%.

    Playing a different game

    Terrestrial and aquatic animals have different challenges and strategies when coping with extreme temperatures, any of which could factor into the differences, the researchers found. Water is very good at retaining heat, so marine animals don’t experience the daily or seasonal temperature fluctuations that most terrestrial animals deal with. McCauley hypothesized that the lack of experience with large temperature fluctuations may be one reason marine species are more susceptible to rising temperatures.

    For instance, a lizard native to the eastern seaboard might experience a difference as high as 50 degrees Fahrenheit between day and night, and perhaps 120 degrees between summer and winter. Those temperature ranges are unheard of for marine species.

    Land animals can also take advantage of thermal refuges — a burrow, a shady tree, a stream — to cool off on a daily basis. But that doesn’t work underwater. “There’s no such thing as a cool shady spot under the sea,” McCauley said. In any given area all the water equalizes to the same temperature.

    Some marine animals seek refuge in cooler water deeper down, but ocean ecosystems can vary over the span of a few dozen feet. Light level, water pressure and food availability quickly change as you dive, meaning this isn’t a strategy that most animals can adopt.

    “So, while it may seem like, ‘why don’t you just go down there to beat the heat,’ for some of these marine animals, that is as infeasible as suggesting deer could adapt by just setting up shop in caves,” McCauley said. The differences are about as extreme.

    Priorities

    McCauley hopes that a better understanding of the scope and scale of global warming’s effects on wildlife will help us tailor our response most efficiently. “Dealing with climate change is a triage exercise where we have to figure out who’s most in trouble, get there and get ahead of the problem as best and as fast as we can,” he said.

    Reducing carbon emissions would make the greatest impact, said McCauley. As we work towards this critical long-term goal, we can also make progress by removing other stressors affecting ocean life. Reducing nutrient and plastic pollution, better managing global fisheries and creating marine reserves can all alleviate pressures on marine animals, giving them a better chance of adapting to long-haul challenges like climate change, he added.

    Some species, like the American lobster, are slowly shifting their range north, but not all animals can do this. Both on land and in the sea, geography and barriers can keep animals from moving to cooler areas. Species living on isolated islands, or in the shallow waters around them, are perfect examples of this.

    Habitat fragmentation only exacerbates the problems associated with these geographic barriers. “If you have species becoming climate refugees that have to flee overheating habitats,” McCauley noted, “roads and fences are going to slow them down or make it downright impossible to travel to cooler habitats.”

    Human impact

    Humans depend on the ocean for their lives and livelihoods, and the researchers are concerned that the patterns they found will affect us as well.

    “The findings suggest that new conservation efforts will be needed if the ocean is going to continue supporting human wellbeing, nutrition and economic activity,” said lead author Malin Pinsky, an associate professor at Rutgers University, New Brunswick.

    “This research was focused more on understanding how the is ocean changing. And the next step is answering the question, ‘Who cares?’” McCauley said. “I want to know, in particular, if and how these impacts on ocean health matter to human health.”

    McCauley and his collaborators have joined health scientists at Harvard University and social scientists at UC Santa Cruz to assess how the disappearance of ocean animals might affect human health and nutrition. The researchers will head to the island nation of Kiribati to work with local communities in understanding how some of these changes may influence them. This includes measuring the fish populations, speaking with fishermen and working with local health officials to measure community nutritional health.

    “In many places like this, oceans are a local life support service,” say McCauley. “In the more remote islands it can be fish and rice for dinner or, if you run out of fish, just rice.”
    Contact Info:

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Santa Barbara Seal
    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
  • richardmitnick 3:15 pm on November 25, 2016 Permalink | Reply
    Tags: INCITE program, , , Stellar mass loss, UC Santa Barbara   

    From UC Santa Barbara’s Kavli Institute for Theoretical Physics (KITP): “Stellar Simulators” 

    UC Santa Barbara Name bloc

    UC Santa Barbara

    KavliFoundation

    The Kavli Foundation

    November 22, 2016
    Julie Cohen

    It’s an intricate process through which massive stars lose their gas as they evolve. And a more complete understanding could be just calculations away, if only those calculations didn’t take several millennia to run on normal computers.

    But astrophysicists Matteo Cantiello and Yan-Fei Jiang of UC Santa Barbara’s Kavli Institute for Theoretical Physics (KITP) may find a way around that problem.

    The pair have been awarded 120 million CPU hours over two years on the supercomputer Mira — the sixth-fastest computer in the world — through the Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program, an initiative of the U.S. Department of Energy Office of Science.

    MIRA IBM Blue Gene Q supercomputer at the Argonne Leadership Computing Facility
    MIRA IBM Blue Gene Q supercomputer at the Argonne Leadership Computing Facility

    INCITE aims to accelerate scientific discoveries and technological innovations by awarding, on a competitive basis, time on supercomputers to researchers with large-scale, computationally intensive projects that address “grand challenges” in science and engineering.

    “Access to Mira means that we will be able to run calculations that otherwise would take about 150,000 years to run on our laptops,” said Cantiello, an associate specialist at KITP.

    Cantiello and Jiang will use their supercomputer time to run 3-D simulations of stellar interiors, in particular the outer envelopes of massive stars. Such calculations are an important tool to inform and improve the one-dimensional approximations used in stellar evolution modeling. The researchers aim to unravel the complex physics involved in the interplay among gas, radiation and magnetic fields in such stars — stellar bodies that later in life can explode to form black holes and neutron stars.

    The physicists use grid-based Athena++ code — which has been carefully extended and tested by Jiang — to solve equations for the gas flow in the presence of magnetic fields (magnetohydrodynamics) and for how photons move in such environments and interact with the gas flow (radiative transfer). The code divides the huge calculations into small pieces that are sent to many different CPUs and are solved in parallel. With a staggering number of CPUs — 786,432 to be precise — Mira speeds up the process tremendously.

    This research addresses an increasingly important problem: understanding the structure of massive stars and the nature of the process that makes them lose mass as they evolve. This includes both relatively steady winds and dramatic episodic mass loss eruptions.

    Called stellar mass loss, this process has a decisive effect on the final fate of these objects. The type of supernova explosion that these stars undergo, as well as the type of remnants they leave behind (neutron stars, black holes or even no remnant at all), are intimately tied to their mass loss.

    The study is particularly relevant in light of the recent detection of gravitational waves from LIGO (Laser Interferometer Gravitational-Wave Observatory). The discovery demonstrated the existence of stellar mass black holes orbiting so close to each other that eventually they can merge and produce the observed gravitational waves.

    “Understanding how these black hole binary systems formed in the first place requires a better understanding of the structure and mass loss of their stellar progenitors,” explained Jiang, a postdoctoral fellow at KITP.

    The implications of the work Cantiello and Jiang will perform on Mira also extend to broader fields of stellar evolution and galaxy formation, among others.

    See the full UCSB article here .
    See the full Kavli article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The Kavli Foundation, based in Oxnard, California, is dedicated to the goals of advancing science for the benefit of humanity and promoting increased public understanding and support for scientists and their work.

    The Foundation’s mission is implemented through an international program of research institutes, professorships, and symposia in the fields of astrophysics, nanoscience, neuroscience, and theoretical physics as well as prizes in the fields of astrophysics, nanoscience, and neuroscience.

    UC Santa Barbara Seal

    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
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