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  • richardmitnick 8:43 am on February 16, 2017 Permalink | Reply
    Tags: , , , UC Berkeley   

    From UC Berkeley: “UC Berkeley, NASA looking for citizen scientists to help find Planet 9” 

    UC Berkeley

    UC Berkeley

    February 15, 2017
    Robert Sanders
    rlsanders@berkeley.edu

    1
    A previously cataloged brown dwarf named WISE 0855−0714 shows up as a moving
    orange dot (upper left) in this loop of WISE images spanning five years. By viewing
    movies like this, anyone can help discover more brown dwarfs or even a 9th planet. (NASA/WISE images)

    Elusive planets and dim failed stars may be lurking around the edges of our solar system, and astronomers from NASA and UC Berkeley want the public’s help to hunt them down.

    Through a new website called Backyard Worlds: Planet 9, anyone can now help search for objects far beyond the orbit of our farthest planet, Neptune, by viewing brief “flipbook” movies made from images captured by NASA’s Wide-field Infrared Survey Explorer (WISE) mission. A faint spot seen moving through background stars might be a new and distant planet orbiting the sun or a nearby brown dwarf.

    NASA/WISE Telescope
    NASA/WISE Telescope

    WISE’s infrared images cover the entire sky about six times over. This has allowed astronomers to search the images for faint, glowing objects that change position over time, which means they are relatively close to Earth. Objects that produce their own faint infrared glow would have to be large, Neptune-size planets or brown dwarfs, which are slightly smaller than stars.

    UC Berkeley postdoctoral researcher Aaron Meisner, a physicist who specializes in analyzing WISE images, has automated the search using computers, but he jumped at the idea by NASA astronomer Marc Kuchner to ask the public to eyeball the millions of WISE images. NASA and its collaborators, including UC Berkeley, are launching the planet and brown dwarf search Feb. 15.

    “Automated searches don’t work well in some regions of the sky, like the plane of the Milky Way galaxy, because there are too many stars, which confuses the search algorithm,” said Meisner, who last month published the results of an automated survey of 5 percent of the WISE data, which revealed no new objects. Online volunteers “using the powerful ability of the human brain to recognize motion” may be luckier, he said.

    “Backyard Worlds: Planet 9 has the potential to unlock once-in-a-century discoveries, and it’s exciting to think they could be spotted first by a citizen scientist,” he added.

    “There are just over four light-years between Neptune, the farthest known planet in our solar system, and Proxima Centauri, the nearest star, and much of this vast territory is unexplored,” said Kuchner, the lead researcher and an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

    Centauris Alpha Beta Proxima 27, February 2012. Skatebiker
    Centauris Alpha Beta Proxima 27, February 2012. Skatebiker

    “Because there’s so little sunlight, even large objects in that region barely shine in visible light. But by looking in the infrared, WISE may have imaged objects we otherwise would have missed.”

    Planet 9

    People have long theorized about unknown planets far beyond Neptune and the dwarf planet Pluto, but until recently there was no evidence to support the idea. Last year, however, Caltech astronomers Mike Brown and Konstantin Batygin found indirect evidence for the existence of an as-yet-unseen ninth planet in the solar system’s outer reaches. This “Planet 9” would be similar in size to Neptune, but up to a thousand times farther from the sun than Earth, and would orbit the sun perhaps once every 15,000 years. It would be so faint as to have so far evaded discovery.


    Video courtesy of the American Museum of Natural History.

    At the moment, the existence of Planet 9 is still under debate. Meisner thinks it’s more likely that volunteers will find brown dwarfs in the solar neighborhood. While Planet 9 would look very blue in WISE time-lapse animations, brown dwarfs would look very red and move across the sky more slowly.

    WISE images have already turned up hundreds of previously unknown brown dwarfs, including the sun’s third- and fourth-closest known neighbors. He hopes that the Backyard Worlds search will turn up a new nearest neighbor to our sun.

    “We’ve pre-processed the WISE data we’re presenting to citizen scientists in such a way that even the faintest moving objects can be detected, giving us an advantage over all previous searches,” Meisner said. Moving objects flagged by participants will be prioritized by the science team for later follow-up observations by professional astronomers. Participants will share credit for their discoveries in any scientific publications that result from the project.

    2
    A very blue Neptune-like planet, dubbed Planet 9, may be lurking dozens of times further from the sun than Pluto, as depicted in this artist’s rendering. Citizen scientists who join the Backyard Worlds: Planet 9 project may be the first to spot it. (NASA image)

    WISE and NEOWISE

    The WISE telescope scanned the entire sky between 2010 and 2011, producing the most comprehensive survey at mid-infrared wavelengths currently available. With the completion of its primary mission, WISE was shut down in 2011, then reactivated in 2013 and given a new mission: assisting NASA’s efforts to identify potentially hazardous near-Earth objects, which are asteroids and comets in the vicinity of our planet. The mission was renamed the Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE).

    The new website uses all of the WISE and NEOWISE data to search for unknown objects in and beyond our own solar system, including the putative Planet 9. If Planet 9 exists and is as bright as some predict, it could show up in WISE data.

    Meisner said WISE is uniquely suited for discovering extremely cold brown dwarfs, which can be invisible to the biggest ground-based telescopes despite being very close.

    “Brown dwarfs form like stars but evolve like planets, and the coldest ones are much like Jupiter,” said team member Jackie Faherty, an astronomer at the American Museum of Natural History in New York. “By using Backyard Worlds: Planet 9, the public can help us discover more of these strange rogue worlds.”

    Backyard Worlds: Planet 9 is a collaboration between NASA, UC Berkeley, the American Museum of Natural History in New York, Arizona State University, the Space Telescope Science Institute in Baltimore and Zooniverse, a collaboration of scientists, software developers and educators that collectively develops and manages citizen-science projects on the internet. Zooniverse will spread the word among its many citizen volunteers

    NASA’s Jet Propulsion Laboratory in Pasadena, California, manages and operates WISE, part of NASA’s Explorers Program.

    Meisner, who specializes in creating high-resolution maps of the universe, is also currently working on the Dark Energy Spectroscopic Instrument, a project at Lawrence Berkeley National laboratory that seeks to learn how mysterious dark energy affects the expansion of the universe.

    LBNL/DESI spectroscopic instrument on the Mayall 4-meter telescope at Kitt Peak National Observatory starting in 2018
    LBNL/DESI spectroscopic instrument on the Mayall 4-meter telescope at Kitt Peak National Observatory starting in 2018

    Follow Backyard Worlds: Planet 9 on Facebook or Twitter, @backyardworlds.

    RELATED INFORMATION

    Backyard Worlds: Planet 9 Zooniverse Project
    Searching for Planet Nine with Coadded WISE and NEOWISE-Reactivation Images
    FindPlanetNine Blog [link did not work]

    See the full article here .

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    Founded in the wake of the gold rush by leaders of the newly established 31st state, the University of California’s flagship campus at Berkeley has become one of the preeminent universities in the world. Its early guiding lights, charged with providing education (both “practical” and “classical”) for the state’s people, gradually established a distinguished faculty (with 22 Nobel laureates to date), a stellar research library, and more than 350 academic programs.

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  • richardmitnick 1:59 pm on December 17, 2016 Permalink | Reply
    Tags: , Boy in the bubble, , , , UC Berkeley   

    From UC Berkeley: “From a single genetic mutation, secrets of ‘boy in the bubble’ disease revealed” 

    UC Berkeley

    UC Berkeley

    December 15, 2016
    Brett Israel
    brett.israel@berkeley.edu

    UC Berkeley was part of an interdisciplinary, international research team that has identified the rare genetic mutation responsible for a unique case of “boy in the bubble” disease, known as severe combined immunodeficiency (SCID), a deadly immune system disorder. The researchers found that the cause was a mutated version of a gene called BCL11B, which also plays an unexpected role in the normal processes of immune system development.

    1
    World of his own: David Vetter (Photo: Courtesy Baylor College of Medicine Archives) http://i2.mirror.co.uk/incoming/article3196066.ece/ALTERNATES/s810/The-Boy-in-the-Bubble.jpg. Just a single case chosen at random from many.

    The discovery of this genetic mutation is the latest of several breakthroughs from this team, which has been accomplished by analyzing exomes — the roughly 2 percent of DNA that contains the instructions for building proteins — to identify the cause of mysterious immunological diseases in newborns.

    “This is a gene that had never been associated with SCID before, which required more advanced genome analysis techniques to discover,” said Berkeley computational biologist Steven Brenner, co-author of the study. “Moreover, unlike variants in every other known SCID gene, this mutation is dominant, which means you only need one copy of this mutation to disrupt multiple aspects of development.”

    The study was published Dec. 1 in the New England Journal of Medicine. The research article was accompanied by a perspective by Michael Lenardo, chief of the Molecular Development of the Immune System Section at the National Institute of Allergy and Infectious Diseases, commissioned by the journal. Lenardo wrote that the study is “an exciting example of recent achievements in the application of contemporary molecular genomics to clinical medicine, especially with regard to congenital diseases…This study reflects remarkable advances in molecular diagnosis.”

    The infant patient featured in the new study was identified through a population-based neonatal screening approach for SCID, which was developed in 2005 by Jennifer Puck, the study’s senior author and a UCSF professor of immunology and pediatrics. The screening indicated a severely compromised immune system, leaving the patient open to a likely fatal series of infections. However, UCSF doctors performed a bone marrow transplant, the standard of care for SCID, which provided the infant with a fully functional immune system.

    In addition to SCID, however, the infant was born with a constellation of abnormal features including craniofacial deformities, loose skin, excess body hair and neurological abnormalities, which suggested that a single rare genetic defect could underlie the patient’s disease.

    In part to determine whether the infant’s parents were carriers of a genetic mutation that could be passed on to future children, the research team set out to scan the genomes of both infant and parents for mutations that could be responsible for the disease. Researchers at UC Berkeley and UCSF built on their productive collaboration with researchers at Tata Consultancy Services to use next-generation exome sequencing to identify a single mutation present in the infant but not the parents — referred to as a de novo mutation — in the BCL11B gene, which had previously been associated primarily with lymphatic cancer. So finding the BLC11B mutation to be causative for SCID was a surprise.

    “We’re entering a new era of genomic medicine,” Puck said. “Our technology has progressed to the point that we can learn a great deal about a disease, and even learn important new facts about normal biology, from just a single patient. In this case we were able to unearth the potentially unique underlying genetic cause of one patient’s disease and come away with brand new understanding of how the immune system develops.”

    In order to understand the biological effects of the patient’s mutation, the researchers collaborated with the team of David Wiest at Fox Chase Cancer Center, in Philadelphia, to introduce the patient’s mutated form of BCL11B into zebrafish, whose immune systems are similar to those of humans. They found that the mutated form of BCL11B produced abnormalities in the zebrafish that mimicked those observed in the patient, including not only a disabled immune system but also similar craniofacial abnormalities. Blocking the mutated gene and replacing it with the normal human gene in embryonic zebrafish reversed all these symptoms, strongly suggesting that abnormal BCL11B was the cause of the symptoms seen in both zebrafish and the human patient.

    The normal BCL11B protein binds to DNA at sites across the genome to activate a wide variety of developmental genes in a precisely orchestrated sequence. Experiments revealed that the BCL11B gene mutation identified in the new study disrupts this protein’s ability to bind to DNA, thereby resulting in the wide array of immunological, neurological and craniofacial disruptions seen in both the human patient and in zebrafish.

    “In this case, however, a mutation in BCL11B turned the protein it produces into a monkey wrench that disrupted many different systems in the body,” Puck said.

    According to Puck, the findings illustrate the power of deeply studying rare diseases in individual patients: “We may never get another patient just like this one,” she said. “But as a result of studying this one case we were able to learn so much about a critical gene in a critical pathway that hadn’t been appreciated before.”

    The research was supported by the National Institutes of Health, Tata Consultancy Services, the Commonwealth of Pennsylvania, the M.D. Anderson Cancer Center, the Fox Chase Cancer Center, the Jeffrey Modell Foundation, the Lisa and Douglas Goldman Fund and the Michelle Platt-Ross Foundation.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Founded in the wake of the gold rush by leaders of the newly established 31st state, the University of California’s flagship campus at Berkeley has become one of the preeminent universities in the world. Its early guiding lights, charged with providing education (both “practical” and “classical”) for the state’s people, gradually established a distinguished faculty (with 22 Nobel laureates to date), a stellar research library, and more than 350 academic programs.

    UC Berkeley Seal

     
  • richardmitnick 10:20 pm on December 15, 2016 Permalink | Reply
    Tags: NASA GOLD, NASA ICON, UC Berkeley   

    From UC Berkeley: “Two NASA satellites slated for 2017 launch will focus on edge of space” 

    UC Berkeley

    UC Berkeley

    December 14, 2016
    Robert Sanders
    rlsanders@berkeley.edu

    1
    NASA’s ICON and GOLD missions will take complementary observations of Earth’s ionosphere and upper atmosphere. NASA image.

    1
    Ionospheric Connection Explorer, or ICON

    2
    NASA’s Global-scale Observations of the Limb and Disk (GOLD) sensor will be hosted on the SES-14 satellite. SES-14 will use a bus like SES-12 (above). Credit: Airbus Defence and Space

    Scientists at UC Berkeley’s Space Sciences Laboratory are preparing for the 2017 launch of an Earth-orbiting satellite to discover how storms in the atmosphere affect storms in the ionosphere.

    The ionosphere is the edge of space where the sun ionizes the air in Earth’s atmosphere to create constantly shifting streams and sheets of charged particles.

    The NASA-funded satellite, called the Ionospheric Connection Explorer, or ICON, will complement observations from a sister satellite also scheduled for launch in 2017: the Global Observations of the Limb and Disk, or GOLD. GOLD is being led by the University of Central Florida, though UC Berkeley space scientist Scott England works on both missions.

    While ICON will orbit Earth at an altitude of 350 miles, observing airglow from charged particles in the ionosphere and neutral particles in the atmosphere, GOLD will take similar measurements while parked in a geostationary orbit 22,000 miles above Earth to get a global view of how the ionosphere changes, England said.

    The goal is to connect what happens in the atmosphere to what happens at the edge of space, and to help understand the disturbances that can lead to severe interference with communications and GPS signals.

    “The ionosphere doesn’t only react to energy input by solar storms,” England said. “Terrestrial weather, like hurricanes and wind patterns, can shape the atmosphere and ionosphere, changing how they react to space weather.

    “We will be using these two missions together to understand how dynamic weather systems are reflected in the upper atmosphere, and how these changes impact the ionosphere.”

    England discussed the upcoming ICON and GOLD missions, both Explorer-class missions managed by the NASA Goddard Spaceflight Center in Maryland, during the annual meeting of the American Geophysical Union in San Francisco.

    See this April 2016 story for more detail about the ICON mission and the scientists who are making it happen.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Founded in the wake of the gold rush by leaders of the newly established 31st state, the University of California’s flagship campus at Berkeley has become one of the preeminent universities in the world. Its early guiding lights, charged with providing education (both “practical” and “classical”) for the state’s people, gradually established a distinguished faculty (with 22 Nobel laureates to date), a stellar research library, and more than 350 academic programs.

    UC Berkeley Seal

     
  • richardmitnick 9:02 pm on December 14, 2016 Permalink | Reply
    Tags: , MyShake app, , UC Berkeley   

    From UC Berkeley: “Quake-detection app captured nearly 400 temblors worldwide” 

    UC Berkeley

    UC Berkeley

    December 14, 2016
    Robert Sanders
    rlsanders@berkeley.edu

    UC Berkeley’s worldwide network of smartphone earthquake detectors has recorded nearly 400 earthquakes since the MyShake app was made available for download in February, with one of the most active areas of the world the fracking fields of Oklahoma.

    1

    2
    From Feb. 12, 2016 – the release date of the MyShake app – until Dec. 1, 2016, 395 earthquakes with confirmed waveforms were detected by MyShake users around the world.

    The Android app harnesses a smartphone’s motion detectors to measure earthquake ground motion, then sends that data back to the Berkeley Seismological Laboratory for analysis. The eventual goal is to send early-warning alerts to users a bit farther from ground zero, giving them seconds to a minute of warning that the ground will start shaking. That’s enough time to take cover or switch off equipment that might be damaged in a quake.

    To date, nearly 220,000 people have downloaded the app, and at any one time, between 8,000 and 10,000 phones are active — turned on, lying on a horizontal surface and connected to a wi-fi network — and thus primed to respond.

    An updated version of the MyShake app will be available for download today (Dec. 14) from the Google Play Store, providing an option for push notifications of recent quakes within a distance determined by the user, and the option of turning the app off until the phone is plugged in, which could extend the life of a single charge in older phones.

    “The notifications will not be fast initially — not fast enough for early warning — but it puts into place the technology to deliver the alerts and we can then work toward making them faster and faster as we improve our real-time detection system within MyShake,” said project leader Richard Allen, a UC Berkeley professor of earth and planetary sciences and director of the seismology lab.

    In a presentation today, during this week’s annual meeting of the American Geophysical Union in San Francisco, UC Berkeley developer and graduate student Qingkai Kong will summarize the app’s performance. Ten months of operation clearly shows that the sensitivity of the smartphone accelerometers and the density of phones in many places are sufficient to provide data quickly enough for early warning. The phones readily detect the first seismic waves to arrive — the less destructive P waves — and send the information to Berkeley in time to issue an alert that the stronger S wave will soon arrive.

    “We already have the algorithm to detect the earthquakes running on our server, but we have to make sure it is accurate and stable before we can start issuing warnings, which we hope to do in the near future,” Kong said.

    3
    The June 10 earthquake near Borrego Springs in San Diego County, a 5.2-magnitude temblor, triggered 103 smartphones with MyShake installed (green dots). The blue star is the epicenter, the red dots are MyShake phones that were not ready to trigger, probably because of human activity, while the yellow-orange dots are phones that were primed but did not trigger.

    The app can detect quakes as small as magnitude 2.5, with the best sensitivity in areas with a greater density of phones. The largest number of phones to record a quake was 103, after the 5.2 magnitude quake that occurred on the San Jacinto fault near Borrego Springs in San Diego County on June 10. Phones 200 kilometers from the epicenter detected that temblor. The largest quake detected occurred on April 16 in Ecuador: a 7.8 magnitude quake that triggered two phones, 170 and 200 kilometers from the epicenter.

    Allen, Kong and their colleagues at Deutsche Telekom’s Silicon Valley Innovation Center believe the app’s performance shows it can complement traditional seismic networks, such as that operated nationally by the U.S. Geological Survey, but can also serve as a stand-alone system in places with few seismic stations, helping to reduce injuries and damage from earthquakes.

    While the app has detected quakes in seismically active areas such as Chile, Mexico, New Zealand, Taiwan, Japan and the West Coast of the U.S., one surprising hot spot has been the traditionally quiet state of Oklahoma. The practice of injecting oil well wastewater deep underground has activated faults in the area to the extent that the state is rattled hundreds of times a year.

    “Oklahoma is now clearly No. 1 in terms of the number of earthquakes in the lower 48 states,” Kong said.

    Most of Oklahoma’s earthquakes are small, but MyShake users in the state, which number only about 200, easily detected the Sept. 3 magnitude 5.8 quake, the strongest ever to hit the state. During that event, 14 phones in the state triggered, but even this relatively small number of phones allowed the seismology lab to peg the magnitude within 1 percent of estimates from ground seismic stations, and located the epicenter to within 4 kilometers (2.5 miles).

    “These initial studies suggest that the data will be useful for a variety of scientific studies of induced seismicity phenomena in Oklahoma, as well as having the potential to provide earthquake early warning in the future,” Kong said.

    He will summarize the Oklahoma data during a poster session on Friday, Dec. 16.


    Richard Allen explains how MyShake can help detect earthquakes and eventually provide early warning for smartphone users. (Video by Roxanne Makasdjian and Stephen McNally)

    The MyShake app and the computer algorithm behind it were developed by Allen, Kong and a team of programmers at the Silicon Valley Innovation Center in Mountain View, California, which is part of the Telekom Innovation Laboratories (T-Labs) operated by Deutsche Telekom, owner of T-Mobile. Louis Schreier, the leader of that team, co-wrote a paper with Allen and Kong on the first six months of MyShake’s observations, published Sept. 29 in the journal Geophysical Research Letters.

    See the full article here .

    YOU CAN HELP CATCH EARTHQUAKES AS THEY HAPPEN RIGHT NOW

    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).

    BOINCLarge

    BOINC WallPaper

    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

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Founded in the wake of the gold rush by leaders of the newly established 31st state, the University of California’s flagship campus at Berkeley has become one of the preeminent universities in the world. Its early guiding lights, charged with providing education (both “practical” and “classical”) for the state’s people, gradually established a distinguished faculty (with 22 Nobel laureates to date), a stellar research library, and more than 350 academic programs.

    UC Berkeley Seal

     
  • richardmitnick 7:32 am on September 23, 2016 Permalink | Reply
    Tags: , Juan de Fuca plate, , , Seismic 'CT scans' reveal deep earth dynamics, Seismic tomography, UC Berkeley   

    From Berkeley via phys.org: “Seismic ‘CT scans’ reveal deep earth dynamics” 

    UC Berkeley

    UC Berkeley

    physdotorg
    phys.org

    September 23, 2016
    Wallace Ravven

    1
    A new look 100 miles beneath a massive tectonic plate as it dives under North America has helped clarify the subduction process that generates earthquakes, volcanoes and the rise of the Cascade Range in the Pacific Northwest.

    The largest array of seismometers ever deployed on the seafloor, coupled with hundreds of others operating in the continental U.S., has enabled UC Berkeley researchers to essentially create CT scans of the Juan de Fuca plate and part of the earth’s mantle directly below it.

    The plate, about the size of the state of Michigan, is grinding under the continent along an 800-mile swath that runs from Northern California to Vancouver Island, known as the Cascadia subduction zone.

    The 3-D imaging process, known as seismic tomography, has revealed with unprecedented clarity a huge, buoyant, sausage-shaped region of the upper mantle, or asthenosphere, pressing up on the oceanic plate.

    The imaging casts new light on the competing hypotheses about the drivers of plate tectonics, a dynamic earth process that has been studied for more than 50 years but is still poorly understood.

    Different evidence has led to three different plate movement scenarios: either the plates are pushed from mid-ocean ridges; or they are pulled from their subducting slabs; or their movement is driven by the drag of the viscous mantle material that lies directly below.

    The new research suggests that the third scenario does not apply to the Cascadia subduction zone. Rather, it reveals that a distinct, thin—and difficult to observe—layer separates the plate from the mantle beneath, at least in the Cascadia subduction zone. The layer acts as a kind of berm that the plate rolls over before descending beneath the continent, says UC Berkeley seismologist Richard Allen, leader of the research and co-author of a paper appearing in the Sept. 23 edition of the journal Science.

    “What we observe is an accumulation of low-viscosity material between the plate and the mantle. Its composition acts as a lubricant, and decouples the plate’s movement from the mantle below it,” explains Allen, who is director of the Berkeley Seismological Laboratory and professor and chair of Earth and Planetary Science at Berkeley. The plates may move independently of the mantle below, he adds.

    The finding, he says, will help refine models of plate tectonic dynamics, aiding the long-range effort to understand the connection between tectonics and earthquakes.

    “It is the motion of the plates that causes earthquakes,” Allen says. “Models like this help us understand that linkage so we can be better informed of the coastal hazards.

    “First though, we need to learn if what we find here is typical of subduction zones across the planet, or if it is unique for some reason.”

    Japan has recently deployed a massive seafloor seismic network to study subduction and earthquakes. Allen hopes to next apply the tomography strategy there. Alaska also beckons.

    Lead author on the Science paper is William Hawley, a graduate student in Allen’s lab.

    “Plate tectonics is the most fundamental concept explaining the formation of features we see on the earth’s surface,” Hawley says, “but despite the fact that the concept is simple, we still do not know exactly why or how it operates.

    “If the asthenosphere acts as a lubricant for tectonic plate movement throughout the planet, it will really change our long-term models of the process”—dynamic changes that occur over a 100 million years.

    “Modelers will have to take this lubricating layer into account because it changes the way the mantle and the plates talk to each other.”

    Seismic tomography generates 3-D images of the earth’s interior by measuring how differences in shape, density, rock type and temperature affect the path, speed and amplitude of seismic waves traveling through the planet from an earthquake.

    Much as in CT scans, computers process differences in energy measured at the receiving end to infer interior 3-D detail. CT scans use X-rays as the energy source, while seismic tomography measures energy from seismic waves.

    A dense array of seismometers directly over the region of interest yields the best images and provides the highest resolution of the structures, which can then inform models of the process.

    This study used the data from the largest scale ocean-floor deployment to complement the onshore data already available. Together, they generated the best images of the region to date.

    The four-year seafloor research effort was made possible by the National Science Foundation’s ambitious $20 million Cascadia Initiative. The NSF aimed to spur greater understanding of plate structure, subduction processes, earthquakes and volcanism by deploying seismometers at 120 sites on the ocean floor, arrayed throughout the 95,000-square-mile Juan de Fuca plate.

    Over the four years, the offshore and onshore seismometer array measured thousands of earthquakes throughout the planet, ranging from magnitudes of 5 to about 9 on the Richter scale. The study examined a subset of 321 quakes with magnitudes between about 6 and 7.5.

    Grad students and faculty scientists participated in 24 research cruises to deploy the instruments and move them between two swaths of the Juan de Fuca plate. Several of the seismic tomography cruises invited undergraduate students on the two-week trips. On one Berkeley-led cruise aboard the R/V Thomas Thompson, the undergrads dubbed the trip the “Tom Cruise,” and sent daily video blogs.

    See the full article here .

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    About Phys.org in 100 Words

    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

    Founded in the wake of the gold rush by leaders of the newly established 31st state, the University of California’s flagship campus at Berkeley has become one of the preeminent universities in the world. Its early guiding lights, charged with providing education (both “practical” and “classical”) for the state’s people, gradually established a distinguished faculty (with 22 Nobel laureates to date), a stellar research library, and more than 350 academic programs.

    UC Berkeley Seal

     
  • richardmitnick 1:53 pm on September 22, 2016 Permalink | Reply
    Tags: Chan Zuckerberg Biohub, UC Berkeley   

    From Berkeley: “UC Berkeley to partner in $600M Chan Zuckerberg science ‘Biohub’” 

    UC Berkeley

    UC Berkeley

    September 21, 2016
    Yasmin Anwar
    yanwar@berkeley.edu

    UC Berkeley, UC San Francisco and Stanford University will join forces in a new medical science research center funded by a $600 million commitment from Facebook CEO and founder Mark Zuckerberg and pediatrician Priscilla Chan.

    Announced today, the San Francisco-based Chan Zuckerberg Biohub, an independent collaboration between the Bay Area’s three premier research universities, is the first philanthropic science investment made by the Chan Zuckerberg Initiative, which is dedicated to “advancing human potential and promoting equality.”

    “We are excited to see such a generous and timely investment in fundamental scientific work across the Bay Area,” said Jennifer Doudna, UC Berkeley professor of molecular and cell biology and chemistry, Li Ka Shing Chancellor’s Chair in Biomedical and Health Sciences, Howard Hughes Medical Institute investigator and a member of the Biohub’s Science Advisory Group.

    “The Biohub will allow researchers at leading institutions to collaborate and accelerate the development of breakthrough scientific and medical advancements, applications and therapeutics,” added Doudna, who is best known for her pioneering work on CRISPR-Cas9, a gene-editing technology that has the potential to revolutionize genetics, molecular biology and medicine.

    Headquartered next to UCSF’s Mission Bay campus, with a satellite site at Stanford, the Biohub will provide basic researchers and clinical scientists with flexible laboratory space, the latest technological tools and funding for ambitious research projects.

    “In bringing together three world-class research universities in UC Berkeley, UCSF, and Stanford, the Biohub represents the type of cross-institutional collaborative environment that will be critical for addressing the most pressing life sciences challenges of our time,” said UC Berkeley Chancellor Nicholas Dirks.

    “Each of these institutions brings its own set of perspectives, questions, ideas, and expertise to this venture, and, given this unprecedented kind of exchange, I am confident that the Biohub will be the catalyst for major and even transformational research breakthroughs,” he added.

    ‘New avenues to treat and cure disease’

    Paul Alivisatos, vice chancellor for research at UC Berkeley and a pioneer of nanoscience, said “this forward-looking gift will empower scientists at the leading edges of their fields to work across disciplines in new ways and to be nimbler and to pursue new ideas.”

    “The research community at UC Berkeley is thrilled to have this new opportunity to collaborate with researchers at UCSF and Stanford to expand our knowledge of human health and lay the groundwork to create new avenues to treat and cure disease,” he said.

    In 2015, Chan and Zuckerberg pledged in an open letter to their newborn daughter to donate 99 percent of their Facebook shares during their lives for charitable purposes. “Partnering with experts,” they wrote, “is more effective for the mission than trying to lead efforts ourselves.”

    They are now making good on their promise, said Robert Tjian, a UC Berkeley professor of biochemistry, biophysics and structural biology who as president of the Howard Hughes Medical Institute — a post he left earlier this month — served as an adviser in the creation of the Chan Zuckerberg Biohub. He will be a member of the President’s Advisory Board at the Biohub and will serve on the Scientific Advisory Board at the larger Chan Zuckerberg Science Initiative.

    “It’s a game changer, not only for the Bay Area and the three respective campuses, but for the life sciences in general,” Tjian said.

    The Biohub will immediately initiate two potentially transformative research projects to be conducted over the next five years: the Cell Atlas and the Infectious Disease Initiative.

    The Cell Atlas will be a map made available to researchers around the world that reveals the many different types of cells that control the body’s major organs, such as the brain, heart, breast and lungs. The Cell Atlas will also depict the internal machinery of cells in unprecedented detail, allowing scientists to search for the basic breakdowns that occur within cells when disease strikes.

    The Infectious Disease Initiative will explore new ways to create drugs, diagnostic tests and vaccines against the many infectious diseases that still threaten much of the world, like HIV, Ebola and Zika. The initiative will include a Rapid Response Team that can immediately devote world-class scientists and advanced research technology to develop new ways to fight a sudden outbreak.

    The Biohub’s open-access model will allow researchers at its three member universities and elsewhere to use its technology and collaborate with scientists at the Biohub, which will provide support for both established and early-career scientists.

    Nurturing young scientists

    Moreover, the Biohub will fund Chan Zuckerberg Investigators to support high-impact projects that may be too exploratory to receive government support. The competition for these slots will open to faculty at the three universities in October. Investigators are expected to be selected by an independent panel of scientists by the end of the year.

    “We have three great research powerhouses in the San Francisco Bay Area, and the Biohub will serve as a completely new nexus of collaboration by providing exceptional resources and opportunities for UCSF, Stanford and Berkeley scientists to create highly productive partnerships,” said Biohub co-director Joseph DeRisi, professor and chair of biochemistry and biophysics at UCSF.

    “The Biohub will be the sinew that ties together these three institutions in the Bay Area like never before,” said Stephen Quake, Stanford professor of bioengineering and of applied physics, who will co-lead the center with DeRisi.

    DeRisi is renowned for his use of genomic technologies for the study of malaria and viruses, and the diagnosis of unknown infections; Quake developed a platform called microfluidics, which can sequence miniscule amounts of DNA or analyze molecules within drops of liquid, technology that has accelerated research into the genetic basis of disease.

    “This exciting new venture by the Chan Zuckerberg Initiative brings together private philanthropy with some of the best minds in the world,” said UC President Janet Napolitano. “Collaboration in the name of science and the public good among the Bay Area’s three leading research universities will surely speed the development of new treatments and cures for diseases once deemed intractable.”

    Advancing the Biohub’s overarching projects will require technologies such as the CRISPR genome-editing technology, advanced cryo-EM, single-cell sequencing platforms as well as single-molecule imaging technologies and the computational infrastructure needed to analyze giant datasets, Tjian said.

    A unique collaboration

    “The three research universities bring great scientific strengths, cross-cutting expertise and a spirit of collaboration,” Tjian said. “For example, Berkeley has both depth and breadth in computational biology and is spearheading the application of next-generation super- resolution live-cell imaging.”

    “There are also great people working on infectious diseases complemented by experts in cell biology to help develop the cell atlas,” he added. “These foundational discovery efforts will be critical to uncover the underlying basis of disease that will inform the development of novel diagnosis platforms and therapies.”

    In addition to the Biohub, the Chan Zuckerberg Initiative has also announced plans for a broader focus on science, its second major initiative, alongside work to improve education for all students.

    The Chan Zuckerberg Initiative’s goal is to cure, prevent or manage all diseases by the end of the century by accelerating basic science research. The initiative seeks to support new ways of enabling scientists and engineers to work together to build new tools that will empower the whole scientific community and advance progress.

    See the full article here .

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  • richardmitnick 1:32 pm on September 16, 2016 Permalink | Reply
    Tags: , , , HERA collaboration, , , UC Berkeley   

    From UC Berkeley and SKA: “Funding boost for SKA Precursor HERA telescope – What happened after the lights came on in the universe?” 

    UC Berkeley

    UC Berkeley

    SKA Square Kilometer Array

    SKA

    From SKA:
    Friday 21 September 2016, SKA Global Headquarters, UK – The Hydrogen Epoch of Reionisation Array (HERA) has been awarded international funding with a $9.5 million investment to expand its capabilities, as announced on Wednesday 14th September by the US National Science Foundation.

    1
    Image of the [beginnings of] HERA telescope at the Losberg Site in the Karoo desert. Credit: Danny Jacobs

    HERA, which was recently granted the status of SKA precursor telescope by SKA Organisation, currently has 19, 14-metre radio dishes at the SKA South Africa Losberg site near Carnarvon. With this fresh injection of $9.5 million, this will allow the array to expand to 220 radio dishes by 2018.

    HERA is an experiment focused on one science goal – detecting the Epoch of Reionization signal – and is not a general facility. As part of this effort, HERA is developing techniques, algorithms, calibration and processing pipelines and hardware optimised towards the detection of the power spectrum of the EOR, all of which will benefit SKA in designing and eventually operating the SKA-low telescope to be based in Australia.

    From UC Berkeley:

    September 14, 2016
    Robert Sanders

    An experiment to explore the aftermath of cosmic dawn, when stars and galaxies first lit up the universe, has received nearly $10 million in funding from the National Science Foundation to expand its detector array in South Africa.

    2
    The HERA collaboration expects eventually to expand to 330 radio dishes in the core array, each pointed straight up to measure radiation originally emitted some 13 billion years ago. Twenty outrigger dishes (not shown) are also planned, bringing the array up to 350 dishes total.

    The experiment, an international collaboration called the Hydrogen Epoch of Reionization Array, or HERA, currently has 19 14-meter (42-foot) radio dishes aimed at the southern sky near Carnarvon, South Africa, and will soon up that to 37. The $9.5 million in new funding will allow the array to expand to 240 radio dishes by 2018.

    Led by UC Berkeley, HERA will explore the billion-year period after hydrogen gas collapsed into the first stars, perhaps 100 million years after the Big Bang, through the ignition of stars and galaxies throughout the universe. These first brilliant objects flooded the universe with ultraviolet light that split or ionized all the hydrogen atoms between galaxies into protons and electrons to create the universe we see today.

    “The first galaxies lit up and started ionizing bubbles of gas around them, and soon these bubbles started percolating and intersecting and making bigger and bigger bubbles,“ said Aaron Parsons, a UC Berkeley associate professor of astronomy and principal investigator for HERA. “Eventually, they all intersected and you got this über bubble, leaving the universe as we observe it today: Between galaxies the gas is essentially all ionized.“

    That’s the theory, anyway. HERA hopes for the first time to observe this key cosmic milestone and then map the evolution of reionization to about 1 billion years after the Big Bang.

    “We have leaned a ton about the cosmology of our universe from studies of the cosmic microwave background, but those experiments are observing just the thin shell of light that was emitted from a bunch of protons and electrons that finally combined into neutral hydrogen 380,000 years after the Big Bang,“ he said. “We know from these experiments that the universe started out neutral, and we know that it ended ionized, and we are trying to map out how it transitioned between those two.“

    “Before the cosmic dawn, the universe glowed from the cosmic microwave background radiation, but there weren’t stars lighting up the universe,“ said David DeBoer, a research astronomer in UC Berkeley’s Radio Astronomy Laboratory. “At some point the neutral hydrogen seeded the stars and black holes and galaxies that relit the universe and led to the epoch of reionization.“

    3
    A 13.8-billion-year cosmic timeline indicates the era shortly after the Big Bang observed by the Planck satellite, the era of the first stars and galaxies observed by HERA and the era of galaxy evolution to be observed by NASA’s future James Webb Space Telescope. (HERA image)

    The HERA array, which could eventually expand to 350 telescopes, consists of radio dishes staring fixedly upwards, measuring radiation originally emitted at a wavelength of 21 centimeters – the hyperfine transition in the hydrogen atom – that has been red-shifted by a factor of 10 or more since it was emitted some 13 billion years ago. The researchers hope to detect the boundaries between bubbles of ionized hydrogen – invisible to HERA – and the surrounding neutral or atomic hydrogen.

    By tuning the receiver to different wavelengths, they can map the bubble boundaries at different distances or redshifts to visualize the evolution of the bubbles over time.

    “HERA can also tell us a lot about how galaxies form,“ Parsons said. “Galaxies are very complex organisms that feed back on themselves, regulating their own star formation and the gas that falls into them, and we don’t really understand how they live, especially at this early time when flowing hydrogen gas ends up as complex structures with spiral arms and black holes in the middle. The epoch of reionization is a bridge between the cosmology that we can theoretically calculate from first principles and the astrophysics we observe today and try to understand.“

    UC Berkeley’s partners in HERA are the University of Washington, UCLA, Arizona State University, the National Radio Astronomical Observatory, the University of Pennsylvania, the Massachusetts Institute of Technology, Brown University, the University of Cambridge in the UK, the Square Kilometer Array in South Africa and the Scuola Normale Superiore in Pisa, Italy.

    Other collaborators are the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, the University of KwaZulu Natal, the University of Western Cape and Rhodes University, all in South Africa, and California State Polytechnic University in Pomona.

    “Astronomers want to know what happened to the universe after it emerged from its so-called ‘dark ages’,” said Rich Barvainis, director of the National Science Foundation program that funds HERA. “HERA will help us answer that question, not by studying the primordial stars and galaxies themselves, but rather by studying how these objects changed the nature of intergalactic space.”

    Searching for a firefly on a searchlight

    The key to detecting these percolating bubbles of ionized gas from the epoch of reionization is a receiver that can detect radio signals from neutral hydrogen a million times fainter than nearby radio noise.

    “The foreground noise, mostly synchrotron emission from electrons spiraling in magnetic fields in our own galaxy, is about a million times stronger than the signal,“ DeBoer said. “This is a real problem, because it’s like looking for a firefly in front of an incredibly powerful searchlight. We are trying to see the firefly and filter out the searchlight.“

    Previous experiments, such as the UC Berkeley-led Precision Array Probing the Epoch of Reionization (PAPER) in South Africa and the Murchison Widefield Array (MWA) in Australia, have not been sensitive enough to detect this signal, but with larger dishes and better signal processing, HERA should do the trick.

    “HERA is a unique, next-generation instrument building on the heritage of PAPER,“ said Parsons, who helped build PAPER a decade ago when he was a graduate student working with the late UC Berkeley astronomer Donald Backer. “It is on the same site as PAPER, we are using a lot of the same equipment, but importantly we have brought together a lot more collaborators, including a lot of the U.S. team that has been working with MWA.“

    The strategy is to build a hexagonal array of radio dishes that minimizes the noise, such as radio reflections in the dishes and wires, that would obscure the signal. A supercomputer’s worth of field programmable gate arrays will cross-correlate the signals from the antennas to finely map a 10-degree swath of southern sky centered at minus-30 degrees latitude. Using a technique adopted from PAPER, they will employ this computer processing power to eliminate the slowly varying noise across the wavelength spectrum – 150-350 centimeters – to reveal the rapidly varying signal from neutral hydrogen as they tune across the radio spectrum.

    Astronomers have already discovered hints of reionization, Parsons said. Measurements of the polarization of the cosmic microwave background radiation show that some of the photons emitted at that early time in the universe have been scattered by intervening electrons possibly created by the first stars and galaxies. And galaxy surveys have turned up some very distant galaxies that show attenuation by intervening intergalactic neutral hydrogen, perhaps the last bit remaining before reionization was complete.

    “We have an indication that reionization should have happened, and we are getting hints of when it might have ended, but we don’t have anything telling us what is going on during it.,“ Parsons added. “That is what we hope to learn with HERA, the actual step-by-step process of how reionization happened.“

    Once astronomers know the reionization process, they can calculate the scattering of radiation from the era of recombination – the cosmic background radiation, or CMB – and remove some of the error that makes it hard to detect the gravitational waves produced by inflation shortly after the Big Bang.

    “There is a lot of cosmology you can do with HERA,“ Parsons said. “We have learned so much from the thin shell of the CMB, but here we will be looking at a full three-dimensional space. Something like 80 percent of the observable universe can be mapped using the 21-centimeter line, so this opens up the next generation of cosmology.“

    Parsons and DeBoer compare HERA to the first experiment to detect the cosmic microwave background radiation, the Cosmic Background Explorer, which achieved its goal in 1992 and won for its leaders – George Smoot of UC Berkeley and Lawrence Berkeley National Laboratory, and John Mather of NASA – the 2006 Nobel Prize in Physics.

    “Ultimately, the goal is to get to the point were we are actually making images, just like the CMB images we have seen,“ DeBoer said. “But that is really, really hard, and we need to learn a fair bit about what we are looking for and the instruments we need to get there. We hope that what we develop will allow the Square Kilometre Array or another big project to actually make these images and get much more science from this pivotal epoch in our cosmic history.“

    See the full SKA article here .
    See the UC Berkeley press release here .
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    Founded in the wake of the gold rush by leaders of the newly established 31st state, the University of California’s flagship campus at Berkeley has become one of the preeminent universities in the world. Its early guiding lights, charged with providing education (both “practical” and “classical”) for the state’s people, gradually established a distinguished faculty (with 22 Nobel laureates to date), a stellar research library, and more than 350 academic programs.

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  • richardmitnick 3:44 pm on June 17, 2016 Permalink | Reply
    Tags: , , , UC Berkeley   

    From UC Berkeley: “Breakout: How black hole jets punch out of their galaxies” 

    UC Berkeley

    UC Berkeley

    June 16, 2016
    Robert Sanders

    A simulation of the powerful jets generated by supermassive black holes at the centers of the largest galaxies explains why some burst forth as bright beacons visible across the universe, while others fall apart and never pierce the halo of the galaxy.


    Access mp4 video here .
    New simulations of the jets produced by rotating supermassive black holes in the cores of galaxies show how, with enough power, the corkscrewing fields (white squiggles) can force their way through surrounding gas and drill out of the galaxy, channeling hot gas into the interstellar medium (top). Less powerful jets get stalled inside the galaxy, however, their magnetic fields breaking and dumping hot gas inside and heating up the galaxy. (Simulations by Alexander Tchekhovskoy, UC Berkeley, and Omer Bromberg, Hebrew University)

    4
    This computer-simulated image shows a supermassive black hole at the core of a galaxy. The black region in the center represents the black hole’s event horizon, where no light can escape the massive object’s gravitational grip. The black hole’s powerful gravity distorts space around it like a funhouse mirror. Light from background stars is stretched and smeared as the stars skim by the black hole. Credit: NASA, ESA, and D. Coe, J. Anderson, and R. van der Marel (STScI)

    About 10 percent of all galaxies with active nuclei — all presumed to have supermassive black holes within the central bulge — are observed to have jets of gas spurting in opposite directions from the core. The hot ionized gas is propelled by the twisting magnetic fields of the rotating black hole, which can be as large as several billion suns.

    A 40-year-old puzzle was why some jets are hefty and punch out of the galaxy into intergalactic space, while others are narrow and often fizzle out before reaching the edge of the galaxy. The answer could shed light on how galaxies and their central black holes evolve, since aborted jets are thought to roil the galaxy and slow star formation, while also slowing the infall of gas that has been feeding the voracious black hole. The model could also help astronomers understand other types of jets, such as those produced by individual stars, which we see as gamma-ray bursts or pulsars.

    “Whereas it was rather easy to reproduce the stable jets in simulations, it turned out to be an extreme challenge to explain what causes the jets to fall apart,” said University of California, Berkeley theoretical astrophysicist Alexander Tchekhovskoy, a NASA Einstein postdoctoral fellow, who led the project. “To explain why some jets are unstable, researchers had to resort to explanations such as red giant stars in the jets’ path loading the jets with too much gas and making them heavy and unstable so that the jets fall apart.”

    1
    This false-color image of the radio jet and lobes in the very bright radio galaxy Cygnus A is an example of the powerful jets that can be produced by supermassive black holes at the cores of large galaxies. (Image by R. Perley, C. Carilli & J. Dreher)

    By taking into account the magnetic fields that generate these jets, Tchekhovskoy and colleague Omer Bromberg, a former Lyman Spitzer Jr. postdoctoral fellow at Princeton University, discovered that magnetic instabilities in the jet determine their fate. If the jet is not powerful enough to penetrate the surrounding gas, the jet becomes narrow or collimated, a shape prone to kinking and breaking. When this happens, the hot ionized gas funneled through the magnetic field spews into the galaxy, inflating a hot bubble of gas that generally heats up the galaxy.

    Powerful jets, however, are broader and able to punch through the surrounding gas into the intergalactic medium. The determining factors are the power of the jet and how quickly the gas density drops off with distance, typically dependent on the mass and radius of the galaxy core.

    The simulation, which agrees well with observations, explains what has become known as the Fanaroff-Riley morphological dichotomy of jets, first pointed out by Bernie Fanaroff of South Africa and Julia Riley of the U.K. in 1974.

    “We have shown that a jet can fall apart without any external perturbation, just because of the physics of the jet,“ Tchekhovskoy said. He and Bromberg, who is currently at the Hebrew University of Jerusalem in Israel, will publish their simulations on June 17 in the journal Monthly Notices of the Royal Astronomical Society, a publication of Oxford University Press.

    Bendable drills

    The supermassive black hole in the bulging center of these massive galaxies is like a pitted olive spinning around an axle through the hole, Tchekhovskoy said. If you thread a strand of spaghetti through the hole, representing a magnetic field, then the spinning olive will coil the spaghetti like a spring. The spinning, coiled magnetic fields act like a flexible drill trying to penetrate the surrounding gas.

    3
    The black hole at the center of the galaxy M87 produced a weak jet that could not break out of the galaxy, as seen in this radio image from 1989. As in the new computer simulation, stalled jets dump hot gas into giant bubble-like structures that heat up the galaxy. These stalled jets may be part of the black hole feedback mechanism that periodically halts the inflow of gas that feeds the black hole. (VLA/NRAO/NSF image)

    The simulation, based solely on magnetic field interactions with ionized gas particles, shows that if the jet is not powerful enough to punch a hole through the surrounding gas, the magnetic drill bends and, due to the magnetic kink instability, breaks. An example of this type of jet can be seen in the galaxy M87, one of the closest such jets to Earth at a distance of about 50 million light-years, and has a central black hole equal to about 6 billion suns.

    “If I were to jump on top of a jet and fly with it, I would see the jet start to wiggle around because of a kink instability in the magnetic field,“ Tchekhovskoy said.“If this wiggling grows faster than it takes the gas to reach the tip, then the jet will fall apart. If the instability grows slower than it takes for gas to go from the base to the tip of the jet, then the jet will stay stable.“

    The jet in the galaxy Cygnus A, located about 600 million light-years from Earth, is an example of powerful jets punching through into intergalactic space.

    Tchekhovskoy argues that the unstable jets contribute to what is called black hole feedback, that is, a reaction from the material around the black hole that tends to slow its intake of gas and thus its growth. Unstable jets deposit a lot of energy within the galaxy that heats up the gas and prevents it from falling into the black hole. Jets and other processes effectively keep the sizes of supermassive black holes below about 10 billion solar masses, though UC Berkeley astronomers recently found black holes with masses near 21 billion solar masses.

    Presumably these jets start and stop, lasting perhaps 10-100 million years, as suggested by images of some galaxies showing more than one jet, one of them old and tattered. Evidently, black holes go through binging cycles, interrupted in part by the occasional unstable jet that essentialy takes away their food.

    The simulations were run on the Savio computer at UC Berkeley, Darter at the National Institute for Computational Sciences at the University of Tennesee, Knoxville, and Stampede, Maverick and Ranch computers at the Texas Advanced Computing Center at the University of Texas at Austin. The entire simulation took about 500 hours on 2,000 computer cores, the equivalent of 1 million hours on a standard laptop.

    The researchers are improving their simulation to incorporate the smaller effects of gravity, buoyancy and the thermal pressure of the interstellar and intergalactic media.

    The work was supported by NASA through Einstein Postdoctoral Fellowship grant number PF3-140115 awarded by the Chandra X-ray Center, operated by the Smithsonian Astrophysical Observatory for NASA under contract NAS8-03060, and the National Science Foundation through an XSEDE computational time allocation TG-AST100040.

    See the full article here .

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    Founded in the wake of the gold rush by leaders of the newly established 31st state, the University of California’s flagship campus at Berkeley has become one of the preeminent universities in the world. Its early guiding lights, charged with providing education (both “practical” and “classical”) for the state’s people, gradually established a distinguished faculty (with 22 Nobel laureates to date), a stellar research library, and more than 350 academic programs.

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  • richardmitnick 8:57 am on February 13, 2016 Permalink | Reply
    Tags: , , , MyShake, UC Berkeley   

    From livescience: “‘MyShake’ App Turns Your Smartphone into Earthquake Detector” 

    Livescience

    February 12, 2016
    Mindy Weisberger

    Earthquake

    Seismologists and app developers are shaking things up with a new app that transforms smartphones into personal earthquake detectors.

    By tapping into a smartphone’s accelerometer — the motion-detection instrument — the free Android app, called MyShake, can pick up and interpret nearby quake activity, estimating the earthquake’s location and magnitude in real-time, and then relaying the information to a central database for seismologists to analyze.

    In time, an established network of users could enable MyShake to be used as an early- warning system, the researchers said.

    UC Berkeley MyShake
    MyShake network

    Crowdsourcing quakes

    Seismic networks worldwide detect earthquakes and convey quake data to scientists around the clock, providing a global picture of the tremors that are part of Earth’s ongoing dynamic processes. But there are areas where the network is thin, which means researchers are missing pieces in the seismic puzzle. However, “citizen- scientists” with smartphones could fill those gaps, according to Richard Allen, leader of the MyShake project and director of the Berkeley Seismological Laboratory in California.

    “As smartphones became more popular and it became easier to write software that would run on smartphones, we realized that we had the potential to use the accelerometer that runs in every smartphone to record earthquakes,” Allen told Live Science.

    How it works

    Accelerometers measure forces related to acceleration: vibration, tilt and movement, and also the static force of gravity’s pull. In smartphones, accelerometers detect changes in the device’s orientation, allowing the phone to know exactly which end is up and to adjust visual displays to correspond to the direction it’s facing.

    Fitness apps for smartphones use accelerometers to pinpoint specific changes in motion in order to calculate the number of steps you take, for example. And the MyShake app is designed to recognize when a smartphone’s accelerometer picks up the signature shaking of an earthquake, Allen said, which is different from other types of vibrating motion, or “everyday shaking.”

    In fact, the earthquake-detection engine in MyShake is designed to recognize an earthquake’s vibration profile much like a fitness app recognizes steps, according to Allen.

    “It’s about looking at the amplitude and the frequency content of the earthquake,” Allen said, “and it’s quite different from the amplitude and frequency content of most everyday shakes. It’s very low-frequency energy and the amplitude is not as big as the amplitude for most everyday activities.”

    In other words, the difference between the highs and lows of the motion generated by an earthquake are smaller than the range you’d find in other types of daily movement, he said.

    Quake, rattle and roll

    When a smartphone’s MyShake app detects an earthquake, it instantly sends an alert to a central processing site. A network detection algorithm is activated by incoming data from multiple phones in the same area, to “declare” an earthquake, identify its location and estimate its magnitude, Allen said.

    For now, the app will only collect and transmit data to the central processor. But the end goal, Allen said, is for future versions of the app to send warnings back to individual users.

    An iPhone version of the app will also be included in future plans for MyShake, according to Allen.For seismologists, the more data they can gather about earthquakes, the better, Allen said. A bigger data pool means an improved understanding of quake behavior, which could help experts design better early warning systems and safety protocols, things that are especially critical in urban areas prone to frequent quake activity. With 2.6 billion smartphones currently in circulation worldwide and an anticipated 6 billion by 2020, according to an Ericsson Mobility Report released in 2015, a global network of handheld seismic detectors could go a long way toward keeping people safe by improving quake preparation and response.

    The findings were published online today (Feb. 12) in the journal Science Advances, and the MyShake app is available for download at myshake.berkeley.edu.

    See the full article here .

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  • richardmitnick 5:32 pm on February 4, 2016 Permalink | Reply
    Tags: , Exoskeletal help for permanently injured people, UC Berkeley   

    From Berkeley: “A new-generation exoskeleton helps the paralyzed to walk” 

    UC Berkeley

    UC Berkeley

    February 3, 2016
    No writer credit found

    Until recently, being paralyzed from the waist down meant using a wheelchair to get around. And although daily life is more accessible to wheelchair users, they still face physical and social limitations. But UC Berkeley’s Robotics and Human Engineering Laboratory has been working to change that.

    The robotics lab, a team of graduate students led by mechanical engineering professor Homayoon Kazerooni, has been working for more than a decade to create robotic exoskeletons that allow those with limited mobility to walk again.

    New exoskeleton
    Steven Sanchez, who was paralyzed from the waist down after a BMX accident, wears SuitX’s Phoenix. “If I had this it would change a lot of things,” he says. (Photo courtesy of SuitX)

    This week, a new, lighter and more agile exoskeleton, for which the Kaz lab developed the original technology, was unveiled earlier this week: The Phoenix, by SuitX, a company that has spun off the robotics lab. Kazerooni is its founder and CEO.

    The Phoenix is lightweight, has two motors at the hips and electrically controlled tension settings that tighten when the wearer is standing and swing freely when they’re walking. Users can control the movement of each leg and walk up to 1.1 miles per hour by pushing buttons integrated into a pair of crutches. It’s powered for up to eight hours by a battery pack worn in a backpack.

    “We can’t really fix their disease,” says Kazerooni. “We can’t fix their injury. But what it would do is postpone the secondary injuries due to sitting. It gives a better quality of life.”

    Kazarooni and his team have developed a series of exoskeletons over the years. Their work in the field began in 2000 with a project funded by the Defense Advanced Research Projects Agency to create a device, now called the Berkeley Lower Extremity Exoskeleton (BLEEX), that could help people carry heavier loads for longer. At that time, Kazerooni also realized the potential use for exoskeletons in the medical field, particularly as an alternative to wheelchairs.

    The team began developing new devices to restore mobility for people who had become paraplegic.

    In 2011, they made the exoskeleton that helped Berkeley senior Austin Whitney, paralyzed from the waist down in a 2007 car accident, make an epic walk across the graduation stage to receive his diploma. Soon after, the Austin Project was created in honor of Whitney, with a goal of finding new technologies to create reliable, inexpensive exoskeleton systems for everyday personal use.

    Today, the Phoenix is one of the lightest and most accessible exoskeletons to hit the market. It can be adjusted to fit varied weights, heights and leg sizes and can be used for a range of mobility hindrances. And, although far from inexpensive at $40,000, it’s about the half the cost of other exoskeletons that help restore mobility.

    Read more about SuitX’s Phoenix suit in the MIT Technology Review.

    See the full article here .

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    Founded in the wake of the gold rush by leaders of the newly established 31st state, the University of California’s flagship campus at Berkeley has become one of the preeminent universities in the world. Its early guiding lights, charged with providing education (both “practical” and “classical”) for the state’s people, gradually established a distinguished faculty (with 22 Nobel laureates to date), a stellar research library, and more than 350 academic programs.

    UC Berkeley Seal

     
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