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  • richardmitnick 2:30 pm on June 9, 2016 Permalink | Reply
    Tags: , , , , VLASS begins   

    From NRAO: “The VLA Sky Survey Pilot Begins” 

    NRAO Icon
    National Radio Astronomy Observatory

    NRAO Banner

    6.9.16

    1
    Claire Chandler, VLASS Project Director

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    The Very Large Array Sky Survey (VLASS) will be a three-epoch (32-month cadence), all-sky, S-band (2-4 GHz) continuum polarimetry survey with 2.5-arcsecond spatial resolution. The survey will span seven years and six VLA configuration cycles, and will begin in 2017, pending successful achievement of the design phase milestones. The total VLA telescope time required for the survey is ~5400 hours, or ~900 hours per configuration cycle.

    With the decision to proceed with the VLASS (see 17 Dec 2015 e-News), a 200-hr pilot in the recently commenced VLA B-configuration of semester 2016A has been approved, with the first observations starting June 2016. This pilot survey will inform VLASS implementation and operational issues associated with the full survey as input to design reviews, while at the same time providing the community with early VLASS-type data products. The pilot will be observed in as similar a mode to the full VLASS as possible, including:

    S-band (2-4 GHz), 1024 x 2 MHz channels
    VLA B-configuration, 2.5-arcsec resolution
    On-The-Fly (OTF) mosaics scanning at 3.31 arcmin/sec in right ascension, at constant declination
    Net mapping speed ~20 deg2/hr, 4-hr scheduling blocks covering 80 deg2 (10o x 8o tiles)

    Some areas will be covered with three passes to provide a similar sensitivity as that expected from three epochs of the full VLASS (70 microJy/beam), while others will be observed with a single pass (120 microJy/beam) to maximize sky coverage. The pilot will cover key galactic and extragalactic fields that have good multi-wavelength ancillary data, as well as covering areas of sky with good prior radio observations for technical validation of the OTF mosaicking observing mode. The total area to be covered will be ~2500 deg2, and will include:

    VLASS Pilot Fields, 3 passes (70 microJy/beam):

    Galactic Plane fields: Galactic Center, Cygnus, Cepheus
    Extragalactic fields: Cosmological Evolution Survey, Sloane Digital Sky Survey (SDSS) Stripe 82, Chandra Deep Field South

    VLASS Pilot Fields, 1 pass (120 microJy/beam):

    SDSS South Galactic Cap / FIRST southern sky for declination > 0 deg
    SDSS North Galactic Cap fields: Great Observatories Origins Deep Survey – North, Elais-N1, Lockman Hole, H-ATLAS North, Bootes

    Raw visibility data will be immediately available through the NRAO archive under project code TVPILOT. Data products (calibrated visibility data, images) will be made available after undergoing quality assurance.

    At this time, we encourage community participation in various Science Working Groups as we define and refine the operational aspects of the pilot survey:

    Extragalactic Working Group
    Galactic Working Group
    Transients Working Group
    Polarization Working Group
    EPO Working Group
    Survey Implementation Working Group
    NRAO Data Products, Archiving and Enhanced Data Products Working Group

    A Google Group has been set up to facilitate discussion and communication within the working groups, please visit to sign up.

    See the full article here .

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    The NRAO operates a complementary, state-of-the-art suite of radio telescope facilities for use by the scientific community, regardless of institutional or national affiliation: the Very Large Array (VLA), the Robert C. Byrd Green Bank Telescope (GBT), and the Very Long Baseline Array (VLBA)*.

    ALMA Array

    NRAO ALMA

    NRAO/GBT radio telescope
    NRAO GBT

    NRAO VLA
    NRAO VLA

    The NRAO is building two new major research facilities in partnership with the international community that will soon open new scientific frontiers: the Atacama Large Millimeter/submillimeter Array (ALMA), and the Expanded Very Large Array (EVLA). Access to ALMA observing time by the North American astronomical community will be through the North American ALMA Science Center (NAASC).
    *The Very Long Baseline Array (VLBA) comprises ten radio telescopes spanning 5,351 miles. It’s the world’s largest, sharpest, dedicated telescope array. With an eye this sharp, you could be in Los Angeles and clearly read a street sign in New York City!

    Astronomers use the continent-sized VLBA to zoom in on objects that shine brightly in radio waves, long-wavelength light that’s well below infrared on the spectrum. They observe blazars, quasars, black holes, and stars in every stage of the stellar life cycle. They plot pulsars, exoplanets, and masers, and track asteroids and planets.

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  • richardmitnick 12:28 pm on June 8, 2016 Permalink | Reply
    Tags: , ALMA Witness Intergalactic Deluge Feeding a Black Hole, , , ,   

    From ALMA: “ALMA Witness Intergalactic Deluge Feeding a Black Hole” 

    ALMA Array

    ALMA

    08 June 2016
    Grant Tremblay
    Yale University
    New Haven, Connecticut, USA
    Tel: +1 207 504 4862
    Email: grant.tremblay@yale.edu

    Francoise Combes
    LERMA, Paris Observatory
    France
    Email: francoise.combes@obspm.fr

    Nicolás Lira T.
    Education and Public Outreach Coordinator
    Joint ALMA Observatory
    Santiago, Chile
    Tel: +56 2 24 67 65 19
    Cell: +56 9 94 45 77 26
    Email: nicolas.lira@alma.cl

    Charles E. Blue
    Public Information Officer
    National Radio Astronomy Observatory
    Charlottesville, Virginia, USA
    Tel: +1 434 296 0314
    Cell: +1 202 236 6324
    E-mail: cblue@nrao.edu

    Richard Hook
    Public Information Officer, ESO

    Garching bei München, Germany

    Tel: +49 89 3200 6655

    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    Masaaki Hiramatsu

    Education and Public Outreach Officer, NAOJ Chile
    Observatory
Tokyo, Japan

    Tel: +81 422 34 3630

    E-mail: hiramatsu.masaaki@nao.ac.jp

    1
    The cosmic weather report, as illustrated in this artist concept, calls for condensing clouds of cold molecular gas around the Abell 2597 Brightest Cluster Galaxy. The clouds condense out of the hot, ionized gas that suffuses the space between the galaxies in this cluster. New ALMA data show that these clouds are raining in on the galaxy, plunging toward the supermassive black hole at its center. Credit: NRAO/AUI/NSF; Dana Berry / SkyWorks; ALMA (ESO/NAOJ/NRAO)

    An international team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) has witnessed a cosmic weather event that has never been seen before – a cluster of towering intergalactic gas clouds raining in on the supermassive black hole at the center of a huge galaxy one billion light-years from Earth. The results will appear in the journal Nature on June 9, 2016.

    The new ALMA observation is the first direct evidence that cold dense clouds can coalesce out of hot intergalactic gas and plunge into the heart of a galaxy to feed its central supermassive black hole. It also reshapes astronomers’ views on how supermassive black holes feed, in a process known as accretion.

    Previously, astronomers believed that, in the largest galaxies, supermassive black holes fed on a slow and steady diet of hot ionized gas from the galaxy’s halo. The new ALMA observation shows that, when the intergalactic weather conditions are right, black holes can also gorge on a clumpy, chaotic downpour of giant clouds of very cold molecular gas.

    “This so-called cold, chaotic accretion has been a major theoretical prediction in recent years, but this is one of the first unambiguous pieces of observational evidence for a chaotic, cold ‘rain’ feeding a supermassive black hole,” said Grant Tremblay, an astronomer with Yale University in New Haven, Connecticut, USA and lead author on the new paper. “It’s exciting to think we might actually be observing this galaxy-spanning ‘rainstorm’ feeding a black hole whose mass is about 300 million times that of our Sun.”

    Tremblay and his team used ALMA to peer into an unusually bright cluster of about 50 galaxies, collectively known as Abell 2597. At its core is a singular massive elliptical galaxy, descriptively named the Abell 2597 Brightest Cluster Galaxy. Spreading over the space between these galaxies is a diffuse atmosphere of hot, ionized plasma, which was previously observed with NASA’s Chandra X-ray Observatory.

    “This very, very hot gas can quickly cool, condense, and precipitate in much the same way that warm, humid air in Earth’s atmosphere can spawn rain clouds and precipitation,” Tremblay said. “The newly condensed clouds then rain in on the galaxy, fueling star formation and feeding its supermassive black hole.”

    Near the center of this galaxy, the researchers discovered this exact scenario: three massive clumps of cold gas careening toward the supermassive black hole in the galaxy’s core at 300 kilometers per second, at about a million kilometers. Each cloud contains as much material as a million Suns and is tens of light-years across.

    Normally, objects on that scale would be difficult to distinguish at these cosmic distances, even with ALMA’s amazing resolution.

    They were revealed, however, by the billion light-year-long “shadows” they cast toward Earth. These shadows, known as absorption features, were formed by the in-falling gas clouds blocking out a portion of the bright background millimeter-wavelength light emitted by electrons spiraling around magnetic fields very near the central supermassive black hole.

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    Deep in the heart of the Abell 2597 Brightest Cluster Galaxy, astronomers see a small cluster of giant gas clouds raining in on the central black hole. They were revealed by the billion light-year-long shadows they cast toward Earth. These ALMA data present the first observational evidence for predicted “chaotic, cold” accretion on a supermassive black hole. Credit: NRAO/AUI/NSF; Dana Berry / SkyWorks; ALMA (ESO/NAOJ/NRAO)

    Additional data from the National Science Foundation’s [NRAO] Very Long Baseline Array indicate that the gas clouds observed by ALMA are only about 300 light-years from the central black hole, essentially teetering on the edge of being devoured, in astronomical terms.

    NRAO/VLA, on the Plains of San Agustin fifty miles west of Socorro, New Mexico.
    NRAO/VLA, on the Plains of San Agustin fifty miles west of Socorro, NM, USA

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    Composite image of Abell 2597 Brightest Cluster Galaxy. The background image (blue) is from the Hubble Space Telescope. The foreground (red) is ALMA data showing the distribution of carbon monoxide gas in and around the galaxy. The pull-out box is the ALMA data of the “shadow” (black) produced by absorption of the millimeter-wavelength light emitted by electrons whizzing around powerful magnetic fields generated by the galaxy’s supermassive black hole. The shadow indicates that cold clouds of molecular gas are raining in on the black hole. Credit: B. Saxton (NRAO/AUI/NSF); G. Tremblay et al.; NASA/ESA Hubble; ALMA (ESO/NAOJ/NRAO)

    While ALMA was only able to detect three clouds of cold gas near the black hole, the astronomers speculate that there may be thousands like them in the vicinity, setting up the black hole for a continuing downpour that could fuel its activity well into the future.

    The astronomers now plan to use ALMA in a broader search for these “rainstorms” in other galaxies in order to determine if such cosmic weather is as common as current theory suggests it might be.


    Access mp4 video here .
    The cosmic weather report, as illustrated in this artist’s concept video, calls for condensing clouds of cold molecular gas around the Abell 2597 Brightest Cluster Galaxy. The clouds condense out of the hot, ionised gas that suffuses the space between the galaxies in this cluster. New ALMA data show that these clouds are raining in on the galaxy, plunging toward the supermassive black hole at its centre. Credit: NRAO/AUI/NSF; Dana Berry/SkyWorks; ALMA (ESO/NAOJ/NRAO). Music: Johan B. Monell

    Additional Information

    This research was presented in a paper entitled “Cold, clumpy accretion onto an active supermassive black hole”, by Grant R. Tremblay et al., to appear in the journal Nature on 9 June 2016. on 9 June 2016.

    The team is composed of Grant R. Tremblay (Yale University, New Haven, Connecticut, USA; ESO, Garching, Germany), J. B. Raymond Oonk (ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, the Netherlands; Leiden Observatory, Leiden University, Leiden, the Netherlands), Françoise Combes (LERMA, Observatoire de Paris, PSL Research University, College de France, CNRS, Sorbonne University, Paris, France), Philippe Salomé (LERMA, Observatoire de Paris, PSL Research University, College de France, CNRS, Sorbonne University, Paris, France), Christopher O’Dea (University of Manitoba, Winnipeg, Canada; Rochester Institute of Technology, Rochester, New York, USA), Stefi A. Baum (University of Manitoba, Winnipeg, Canada; Rochester Institute of Technology, Rochester, New York, USA), G. Mark Voit (Michigan State University, East Lansing, Michigan, USA), Megan Donahue (Michigan State University, East Lansing, Michigan, USA), Brian R. McNamara (Waterloo University, Waterloo, Ontario, Canada), Timothy A. Davis (Cardiff University, Cardiff, United Kingdom; ESO, Garching, Germany), Michael A. McDonald (Kavli Institute for Astrophysics & Space Research, MIT, Cambridge, Massachusetts, USA), Alastair C. Edge (Durham University, Durham, United Kingdom), Tracy E. Clarke (Naval Research Laboratory Remote Sensing Division, Washington DC, USA), Roberto Galván-Madrid (Instituto de Radioastronomía y Astrofísica, UNAM, Morelia, Michoacán, México; ESO, Garching, Germany), Malcolm N. Bremer (University of Bristol, Bristol, United Kingdom), Louise O. V. Edwards (Yale University, New Haven, Connecticut, USA), Andrew C. Fabian (Institute of Astronomy, Cambridge University, Cambridge, United Kingdom), Stephen Hamer (LERMA, Observatoire de Paris, PSL Research University, College de France, CNRS, Sorbonne University, Paris, France) , Yuan Li (University of Michigan, Ann Arbor, Michigan, USA ), Anaëlle Maury (Laboratoire AIMParis-Saclay, CEA/DSM/Irfu CNRS, University Paris Diderot, CE-Saclay, Gif-sur-Yvette, France), Helen Russell (Institute of Astronomy, Cambridge University, Cambridge, United Kingdom), Alice C. Quillen (University of Rochester, Rochester, New York, USA), C. Megan Urry (Yale University, New Haven, Connecticut, USA), Jeremy S. Sanders (Max-Planck-Institut für extraterrestrische Physik, Garching bei München, Germany), and Michael Wise (ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, the Netherlands).

    See the full article here .

    Please help promote STEM in your local schools.
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    The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Academia Sinica (AS) in Taiwan.

    ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI) and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

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    ESO 50

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  • richardmitnick 8:48 am on June 5, 2016 Permalink | Reply
    Tags: , , , , , Uncertain Future for Earth’s Still Biggest Telescope   

    From nationalgeographics.com: “Uncertain Future for Earth’s Biggest Telescope” 

    National Geographic

    National Geographics

    06/4/2016
    Nadia Drake

    1
    The Arecibo Observatory, easily recognizable from feature films and a symbol of the search for extraterrestrial life, may not be around for much longer. A harsh funding climate is forcing the National Science Foundation to make some hard decisions about which facilities to keep around. (NSF/Wikimedia)

    Tucked into a sinkhole in the Puerto Rican jungle, the world’s largest single-dish radio telescope scans the skies for signs of distant galaxies, elusive gravitational waves, and the murmurs of extraterrestrial civilizations nearly 24 hours a day. For more than a half-century, whether those waves traveled to Earth from the far reaches of our universe or much closer to home, the Arecibo Observatory has been there to catch them.

    But the enormous telescope, with a dish that stretches 1,000 feet across, may not be around for much longer.

    On May 23, the National Science Foundation, which funds the majority of Arecibo’s annual $12 million budget, published a notice of intent to prepare an environmental impact statement related to the observatory’s future.

    That might sound innocuous – after all, isn’t it a good idea to study the context in which our science facilities exist? Yet it’s anything but benign. Putting that environmental assessment together is a crucial step NSF needs to take if it plans to yank funding from the observatory and effectively shut it down.

    “It appears that NSF is following the formal process established, in part, by the National Environmental Policy Act of 1969, for decommissioning of a federal facility,” says Robert Kerr, former director of the observatory. “The good folks at Arecibo are scared to death.”

    The decision to close Arecibo hasn’t been made yet, but the move follows an ominous drumbeat of similar announcements and reports that have accumulated over several years, most urging NSF to send its resources elsewhere. Now, options for Arecibo’s future range from continuing current operations to dismantling the telescope and returning the site to its natural state. It’s a decision NSF hopes to make — with input from the public — by the end of 2017, says Jim Ulvestad, director of NSF’s Division of Astronomical Sciences.

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    Above the 1000-foot dish, a 900-ton platform is suspended from three tall towers. (Nadia Drake)

    The most extreme option, which could include explosively demolishing the giant dish, might affect such things as ground water, air quality, and ecosystems – thus the importance of studying the environmental impact of potential futures, especially ones that involve shutting the telescope’s eyes.

    “On a practical level, the telescope would in time — perhaps a short time, given the tropical site — become very unsafe,” says Cornell University’s Don Campbell, a former observatory director. “Short of permanently guarding it, deconstruction would be necessary.”

    Not surprisingly, this notice of intent is causing significant concern among astronomers and the local community. Arecibo is the most sensitive radio telescope in the world; and despite its age, it’s still involved in world-class science, like the search for gravitational waves. Importantly, it also helps boost a sagging local economy, and has inspired many Puerto Ricans to pursue science and think about the mysteries of the universe.

    “Puerto Rico feels a sense of ownership and pride for the observatory,” says Emmanuel Donate, an astronomy graduate student at the University of Georgia who started a petition to keep the observatory funded. “I consider using it, especially in person as I’ve been doing the last couple weeks, one of the highlights of my life and a tremendous personal honor.”

    A Tropical Icon

    Construction at Arecibo began in 1960, when – among other things – the U.S. government wanted to find out if Soviet ICBMs could be detected using charged particles in their atmospheric wakes. The telescope didn’t work well at first, but after a few upgrades it was the most sensitive cosmic radio wave detector in the world. That’s not it’s only trick, though: In addition to collecting photons from space, Arecibo is also capable of sending radio waves into the cosmos, a talent scientists use to scrutinize potentially catastrophic asteroids on Earth-crossing orbits.

    3
    The Arecibo Observatory, as seen on Google Earth.

    In the intervening decades, Arecibo has been involved in loads of top-notch science, including work that was awarded a Nobel Prize. But it’s also become a recognizable symbol of humanity’s quest to understand our place in the cosmos (my dad, a former observatory director, used Arecibo to send Earth’s first intentional postcard to the stars in 1974), and is a semi-frequent character in popular films and TV series, including The X-Files, Contact, and GoldenEye.

    To say the telescope is iconic is not an overstatement.

    Stormclouds on the Horizon

    But a frustratingly flatlined budget is forcing the National Science Foundation to ration its resources. To do that, NSF relies on a somewhat contorted process of soliciting input from external reviews and panels, federal advisory boards, and the National Research Council’s decadal surveys, which prioritize science goals for the coming decade.

    “NSF, like most federal science agencies, has much more worthy science proposed to it than it is able to fund,” Ulvestad says. “Within the constraints of its resources, NSF responds as well as possible to those community and governmental science priorities and recommendations.”

    The most recent decadal survey, published in 2010, prioritized science requiring new facilities instead of experiments that could be conducted at places like Arecibo. That survey, in combination with the dismal funding situation, is what’s causing NSF to look for facilities to dump.

    4
    Arecibo’s dish is suspended above the floor of the natural depression it sits in. Beneath it, plants grow like crazy. (Nadia Drake)

    Despite its iconic status, Arecibo is an easy target – newer, shinier telescopes are coming online, and it’s got a relatively small number of users compared to optical telescopes across the United States, many of which are individually less expensive to run.

    Over the past decade, multiple panels have called for severe reductions in funding for the observatory, starting with a 2006 NSF review that recommended finding alternative sources of cash for Arecibo. “The [senior review] recommends closure after 2011 if the necessary support is not forthcoming,” the report says. “This raises the important question of the cost of decommissioning the telescope, which could be prohibitively large.”

    That review was followed by a 2012 assessment of the facilities funded by NSF’s astronomical sciences division. While somewhat less gloomy – the committee recommended keeping the observatory in NSF’s portfolio – the 2012 panel suggested revisiting Arecibo’s funding status later in the decade, “in light of the science opportunities and budget forecasts at that time.”

    NSF followed that review with a 2013 letter saying it would begin studying the costs and impact of decommissioning the giant telescope – a matter that would be complicated by the telescope’s history and location in a region of high biodiversity, “thus these reviews should be started as soon as practicable.”

    The cloudy outlook intensified this year, when NSF’s Astronomy and Astrophysics Advisory Committee urged the agency to proceed with divestment “as fast as is practical.” That was quickly followed by another NSF review that advised a 75% reduction in funding from the agency’s Atmospheric and Geospace Sciences division (AGS), slashing contributions to atmospheric research from $4.1 million to $1.1 million.

    And now, the sky is looking dark indeed.

    “The timing of the federal register announcement in juxtaposition with the AGS review is being received by most as the final death sentence for Arecibo,” Kerr says.

    Ulvestad says that before any such decision is reached, communities that rely on the observatory will have an opportunity to share their concerns. On June 7, the first of these meetings will take place in Puerto Rico, and a public comment period is open until June 23. After the results of the draft environmental impact statement are released, a 45-day public comment period will follow.

    And then? Either the storm will hit or it won’t.

    “To be fair to the NSF, AST and AGS are reacting to a very difficult budget situation — no significant increase in several years and none forecast,” Campbell says.

    Scanning the Cosmos

    Now, Arecibo’s projects include detecting mysterious bursts of radio waves coming from far, far away, testing cosmological models by studying small galaxies in the local universe, and studying those potentially planet-killing asteroids – as well as the moons of distant planets.

    “There is much concern, not just in the small bodies community, but in the planetary science community as a whole regarding the future of Arecibo,” says Nancy Chabot of the Johns Hopkins University Applied Physics Laboratory. Chabot chairs NASA’s Small Bodies Assessment Group, which published a report earlier this year urging NASA to continue supporting the observatory, in the name of preserving “the nation’s science and security interests.”

    Among astronomers, perceptions are that NSF’s move to decommission Arecibo has been gaining momentum as challenges from new facilities arise. One potential thorn in Arecibo’s side is ALMA, the ultrasensitive array of radio telescopes recently completed in the Chilean Atacama.

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array

    Some scientists speculate that with continued resources devoted to ALMA, NSF could be looking to share the relative wealth and spend its money on something other than radio. And that might make sense, especially given that China is nearly done constructing a single-dish radio telescope that will be larger than Arecibo. Called the Five-hundred-meter Aperture Spherical Telescope, the behemoth could possibly open its eyes this fall, though real science observations won’t begin right away.

    FAST Chinese Radio telescope under construction, Guizhou Province, China
    “FAST Chinese Radio telescope under construction, Guizhou Province, China

    Despite its size, FAST won’t necessarily be more sensitive than Arecibo, and it won’t have a built-in radar, which can be used to give the most accurate orbital information for asteroids which might impact the Earth.

    Cornell University’s Jim Cordes points out that newer facilities don’t necessarily have to replace older, high-quality telescopes, especially when those older facilities still provide unique capabilities. They can be complementary, he says, pointing out that scores of similar optical telescopes exist in tandem, such as the two nearly identical Keck telescopes at the summit of Hawaii’s Mauna Kea.

    Keck Observatory, Mauna Kea, Hawaii, USA
    Keck Observatory, Mauna Kea, Hawaii, USA

    “It’s sort of like there’s a disconnect in the way people think about radio telescopes and optical telescopes,” Cordes says.

    More importantly, Cordes notes, some experiments actually require multiple extremely sensitive telescopes. One of these, called NANOGrav, uses Arecibo and a telescope at the National Radio Astronomy Observatory in Green Bank, West Virginia to search for gravitational waves.

    NANOGrave Gravitational waves JPL-Caltech  David Champion
    NANOGrave Gravitational waves JPL-Caltech David Champion

    NRAO/GBT radio telescope
    NRAO/GBT radio telescope

    The project does this by observing pulsars, spinning stellar corpses that act as astronomical clocks. As these dense, dead stars rotate, they emit beams of radio waves that can be detected from Earth; gravitational waves, similar to those detected earlier this year by the LIGO collaboration, sweep through and disrupt the signals coming from those spinning clocks in observable ways…as long as a sharp set of eyes is paying attention.

    A National Inspiration?

    It seems clear that Arecibo won’t go down without a fight, but it’s not exactly clear what form that fight will take. Interestingly, former observatory director Robert Kerr threw one punch by beginning the process for listing Arecibo as a national historic site.

    “It was entirely my intention that the National Historic Registry be an impediment to site closure,” he says, adding that “others assisting with that application may have had other motivations, such as enhanced tourist appeal.”

    And NASA, which funds the planetary radar experiments at Arecibo, also may have something to say about NSF shutting down the facility. It’s also possible that another institution, or someone with enough spare cash might decide to step in.

    “I hope that they do find another institution to contribute to the costs but it will depend on the conditions,” Campbell says. “The alternative is grim for science, for Puerto Rico and, especially given Puerto Rico’s current situation, for the Observatory’s local staff. The staff are an incredible hard working and supportive group.”

    Indeed, generations of Puerto Ricans have visited the observatory, in addition to those who have worked, studied, and lived there.

    “I grew up in the city of Arecibo, I grew up knowing that in the mountains south of the city great science was being done,” says Pablo Llerandi-Román, a geologist at the University of Puerto Rico, Rio Piedras. For Llerandi, science became more than just a subject in school when he visited the observatory as a student and talked with the researchers on site. “If Arecibo shuts down,” he says, “A major aspect of my arecibeño and Puerto Rican scientist pride would be lost.”

    Carlos Estevez Galarza, a student at the University of Puerto Rico, says he hopes Puerto Ricans will one day be as celebrated for their commitment to science as they are for their passions for arts and sports – and he thinks the observatory plays an important role in that.

    “The Arecibo Observatory and its staff were the only ones who believed in me, when no one did,” Galarza says. He worked as a student research assistant at the observatory, studying Mars, and has since presented his work at international conferences and submitted his first paper to a science journal.

    “The most important thing about my experience at the Arecibo Observatory is that I found my purpose,” he continues. “There are many talented Puerto Rican students who deserve the chance that I had.”

    One of those students is still in high school. Now 16, Wilbert Andres Ruperto Hernandez wanted to be an astronaut as a kid – and he wanted to get some hands-on experience in science and engineering. So he enrolled in the Arecibo Observatory Space Academy, which offers high school students the opportunity to design experiments, then collect and analyze data. Now, Hernandez says, he wants to study mechanical engineering or space sciences in college, and has discovered a yearning to understand how the universe works – something that emerged while working with and talking to scientists at the observatory.

    “The fact that we have yet to discover and learn more about ourselves, where we live in and all the things that surround us, motivates me the most to investigate and study these fields,” he says. “Being part of Arecibo Observatory and AOSA has been the greatest experience in my life.”

    See the full article here .

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    The National Geographic Society has been inspiring people to care about the planet since 1888. It is one of the largest nonprofit scientific and educational institutions in the world. Its interests include geography, archaeology and natural science, and the promotion of environmental and historical conservation.

     
  • richardmitnick 12:44 pm on June 3, 2016 Permalink | Reply
    Tags: , , Blazar 1ES1741+196, ,   

    From CfA: “A Blazing Gamma-Ray Source” 

    Harvard Smithsonian Center for Astrophysics


    Center For Astrophysics

    Blazars are galaxies whose central, supermassive black holes are accreting material from surrounding regions. Although black hole accretion happens in many galaxies and situations, in the case of a blazar the infalling material erupts into a powerful, narrow beam of high velocity charged particles that, fortuitously, is pointed in our direction.

    Blazar. NASA Fermi Gamma ray Space Telescope. Credits M. Weiss/ CfA
    Blazar. NASA Fermi Gamma ray Space Telescope. Credits M. Weiss/ CfA

    The charged particles produce gamma ray photons, each photon packing over a hundred million times the energy of the highest energy X-ray photon seen by the Chandra X-ray Observatory. The electron beam produces many other effects, and in blazars these include rapid, strong, and incessant variability. They sometimes also include the ability to generate high-energy gamma rays.

    The blazar 1ES1741+196 was first spotted in 1996 by the Einstein X-ray satellite.

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    Einstein X-ray satellite

    Followup observations determined that it is a triplet system: an elliptical galaxy with two companion galaxies close enough nearby to be an interacting triplet; a tidal tail is observed, for example, presumably the result of mutual gravitation influences. The interactions might play a role in stirring up material for black hole accretion. In 2011, astronomers discovered that the object also emitted gamma rays, but at an intensity that made it one of the faintest such sources known.

    VERITAS, the Very Energetic Radiation Imaging Telescope Array System, is an observatory designed to study gamma rays.

    CfA/VERITAS
    CfA/VERITAS, AZ, USA

    It consists of four 12-m telescopes located at the Fred L. Whipple Observatory at Mt. Hopkins, Arizona. CfA astronomers Wystan Benbow, M. Cerruti, Pascal Fortin, V. Pelassa, and Thomas Roche were members of a team of eighty-eight astronomers who used VERITAS to study 1ES1741+196 in an effort to model this weak gamma ray blazar. They observed it successfully in several energy ranges for thirty hours over a period of several years and were able to obtain, and model, the first very high energy spectrum for the source. In general, high energy photons are produced in two processes: direct radiation from the charged particles, and scattering by the fast-moving particles of lower energy photons to much higher energies. The team successfully modeled this source including only these two, energetic processes. The result suggests that the scientists have accurately characterized this blazar – despite its faintness – as being among those that produce the most energetic gamma rays. They also found, curiously, that there is no evidence for any significant flaring in this source.

    Reference(s):

    VERITAS and Multiwavelength Observations of the BL Lacertae Object 1ES 1741+196, A. U. Abeysekara et al. MNRAS 459, 2550, 2016.

    See the full article here .

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    Stem Education Coalition

    The Center for Astrophysics combines the resources and research facilities of the Harvard College Observatory and the Smithsonian Astrophysical Observatory under a single director to pursue studies of those basic physical processes that determine the nature and evolution of the universe. The Smithsonian Astrophysical Observatory (SAO) is a bureau of the Smithsonian Institution, founded in 1890. The Harvard College Observatory (HCO), founded in 1839, is a research institution of the Faculty of Arts and Sciences, Harvard University, and provides facilities and substantial other support for teaching activities of the Department of Astronomy.

     
  • richardmitnick 6:03 pm on June 2, 2016 Permalink | Reply
    Tags: , , New Observational Distance Record Promises Important Tool for Studying Galaxies, ,   

    From NRAO: “New Observational Distance Record Promises Important Tool for Studying Galaxies” 

    NRAO Icon
    National Radio Astronomy Observatory

    NRAO Banner

    2 June 2016
    Dave Finley, Public Information Officer
    (575) 835-7302
    dfinley@nrao.edu

    1
    Radio-optical image of the galaxy J100054. Background image is visible-light as seen with Hubble Space Telescope. Orange shows radio emission from atomic hydrogen gas surrounding the galaxy. CREDIT: Fernandez et al., Bill Saxton, NRAO/AUI/NSF; Koekemoer et al., Massey et al., NASA.

    Astronomers have used new capabilities of the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) to open a whole new realm of research into how galaxies evolve and interact with their surroundings over cosmic time. They detected the faint radio emission from atomic hydrogen, the most abundant element in the Universe, in a galaxy nearly 5 billion light-years from Earth.

    “This almost doubles the distance record for this type of observation, and promises key new insights into how galaxies draw in the gas, process it, and lose it as they evolve,” said Ximena Fernandez, of Rutgers University. “As we look farther out in distance, we’re looking farther back in time, so this new capability allows us to gain previously unobtainable information about how galaxies develop,” she added.

    The scientists detected the radio “fingerprint” of hydrogen in a galaxy called COSMOS J100054. The discovery came from the first 178 hours of observation in a program called the COSMOS HI Large Extragalactic Survey, or CHILES, led by Jacqueline van Gorkom of Columbia University. The CHILES project eventually will use more than 1,000 hours of VLA observing time. The detection was made possible by the improved capabilities of the VLA provided by a 10-year upgrade project completed in 2012.

    “The new electronic systems in the upgraded VLA were essential to this work. Without the upgrade, this discovery would have been impossible. This detection is the first of what we believe will be many more to come, making an important contribution to our understanding of how galaxies evolve,” said Emmanuel Momjian, of the National Radio Astronomy Observatory.

    Hydrogen gas is the raw material for making stars. Throughout their lives, galaxies draw in the gas, which eventually is incorporated into stars. In furious bursts of star formation, stellar winds and supernova explosions can blow gas out of the galaxy and rob it of the material needed for further star formation.

    In order to understand how these processes develop, astronomers need images of the gas in and near galaxies of different ages. Until now, technical limitations of radio telescopes prevented them from detecting atomic hydrogen emission at the distances needed to see the gas in galaxies distant enough to provide the required “lookback time.” The CHILES project will achieve this to distances out to about 6 billion light-years.

    COSMOS J100054 is in a region of sky extensively studied with multiple telescopes as part of an international project called the Cosmological Evolution Survey (COSMOS). Data from that survey allowed the scientists to glean additional information about the galaxy. In addition, Hansung Gim of the University of Massachusetts, Amherst, used the Large Millimeter Telescope in Mexico to detect Carbon Monoxide (CO) in the galaxy.

    Large Millimeter Telescope Alfonso Serrano
    Large Millimeter Telescope Alfonso Serrano, Mexico

    The CO detection gave the researchers key information about gas in the galaxy that is composed of molecules, rather than of individual atoms. Molecular gas is considered a necessary precursor to star formation.

    The scientists found that COSMOS J100054 is a massive, barred spiral galaxy that may be interacting with a small neighbor galaxy. With an amount of hydrogen nearly 100 billion times the mass of the Sun, the galaxy is forming the equivalent of about 85 suns every year.

    “This is the first time we have been able to observe both the emission from atomic hydrogen and from carbon monoxide in a galaxy that is beyond our local Universe,” Gim said. “Now that we have this capability, we soon will be able to start filling in gaps in our knowledge about the properties of galaxies at specific ages. This is an important development,” he added.

    The research was the work of an international team of astronomers from North America, South America, Europe, Asia and Australia. The scientists are reporting their results* in the Astrophysical Journal Letters.

    *Science paper:
    HIGHEST REDSHIFT IMAGE OF NEUTRAL HYDROGEN IN EMISSION: A CHILES DETECTION OF A STARBURSTING GALAXY AT z = 0.376

    See the full article here .

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    The NRAO operates a complementary, state-of-the-art suite of radio telescope facilities for use by the scientific community, regardless of institutional or national affiliation: the Very Large Array (VLA), the Robert C. Byrd Green Bank Telescope (GBT), and the Very Long Baseline Array (VLBA)*.

    ALMA Array

    NRAO ALMA

    NRAO GBT
    NRAO GBT

    NRAO VLA
    NRAO VLA

    The NRAO is building two new major research facilities in partnership with the international community that will soon open new scientific frontiers: the Atacama Large Millimeter/submillimeter Array (ALMA), and the Expanded Very Large Array (EVLA). Access to ALMA observing time by the North American astronomical community will be through the North American ALMA Science Center (NAASC).
    *The Very Long Baseline Array (VLBA) comprises ten radio telescopes spanning 5,351 miles. It’s the world’s largest, sharpest, dedicated telescope array. With an eye this sharp, you could be in Los Angeles and clearly read a street sign in New York City!

    Astronomers use the continent-sized VLBA to zoom in on objects that shine brightly in radio waves, long-wavelength light that’s well below infrared on the spectrum. They observe blazars, quasars, black holes, and stars in every stage of the stellar life cycle. They plot pulsars, exoplanets, and masers, and track asteroids and planets.

     
  • richardmitnick 9:10 am on June 1, 2016 Permalink | Reply
    Tags: , , , , ,   

    From Rutgers: “Measuring a Black Hole 660 Million Times as Massive as Our Sun” 

    Rutgers University
    Rutgers University

    May 5, 2016 [Just appeared in social media.]
    Todd B. Bates

    Findings by Rutgers and other scientists could help shed light on how galaxies and their supermassive black holes form.

    1
    This is NGC 1332, a galaxy with a black hole at its center whose mass has been measured with high precision by ALMA.
    Photo: Carnegie-Irvine Galaxy Survey

    It’s about 660 million times as massive as our sun, and a cloud of gas circles it at about 1.1 million mph.

    This supermassive black hole sits at the center of a galaxy dubbed NGC 1332, which is 73 million light years from Earth. And an international team of scientists that includes Rutgers associate professor Andrew J. Baker has measured its mass with unprecedented accuracy.

    2
    Andrew J. Baker

    Their groundbreaking observations, made with the revolutionary Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, were published* today in the Astrophysical Journal Letters. ALMA, the world’s largest astronomical project, is a telescope with 66 radio antennas about 16,400 feet above sea level.

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array

    Black holes – the most massive typically found at the centers of galaxies – are so dense that their gravity pulls in anything that’s close enough, including light, said Baker, an associate professor in the Astrophysics Group in Rutgers’ Department of Physics and Astronomy. The department is in the School of Arts and Sciences.

    A black hole can form after matter, often from an exploding star, condenses via gravity. Supermassive black holes at the centers of massive galaxies grow by swallowing gas, stars and other black holes. But, said Baker, “just because there’s a black hole in your neighborhood, it does not act like a cosmic vacuum cleaner.”

    Stars can come close to a black hole, but as long as they’re in stable orbits and moving fast enough, they won’t enter the black hole, said Baker, who has been at Rutgers since 2006.

    “The black hole at the center of the Milky Way, which is the biggest one in our own galaxy, is many thousands of light years away from us,” he said. “We’re not going to get sucked in.”

    Scientists think every massive galaxy, like the Milky Way, has a massive black hole at its center, Baker said. “The ubiquity of black holes is one indicator of the profound influence that they have on the formation of the galaxies in which they live,” he said.

    Understanding the formation and evolution of galaxies is one of the major challenges for modern astrophysics. The scientists’ findings have important implications for how galaxies and their central supermassive black holes form. The ratio of a black hole’s mass to a galaxy’s mass is important in understanding their makeup, Baker said.

    Research suggests that the growth of galaxies and the growth of their black holes are coordinated. And if we want to understand how galaxies form and evolve, we need to understand supermassive black holes, Baker said.

    Part of understanding supermassive black holes is measuring their exact masses. That lets scientists determine if a black hole is growing faster or slower than its galaxy. If black hole mass measurements are inaccurate, scientists can’t draw any definitive conclusions, Baker said.

    To measure NGC 1332’s central black hole, scientists tapped ALMA’s high-resolution observations of carbon monoxide emissions from a giant disc of cold gas orbiting the hole. They also measured the speed of the gas.

    “This has been a very active area of research for the last 20 years, trying to characterize the masses of black holes at the centers of galaxies,” said Baker, who began studying black holes as a graduate student. “This is a case where new instrumentation has allowed us to make an important new advance in terms of what we can say scientifically.”

    He and his coauthors recently submitted a proposal to use ALMA to observe other massive black holes. Use of ALMA is granted after an annual international competition of proposals, according to Baker.

    ALMA is an international partnership of the National Radio Astronomy Observatory, European Southern Observatory and National Astronomical Observatory of Japan in cooperation with Chile. U.S. access to ALMA comes via the National Radio Astronomy Observatory, which is supported by the National Science Foundation.

    Coauthors of the study of NGC 1332’s central black hole include: lead author Aaron J. Barth, Benjamin D. Boizelle and David A. Buote of the University of California, Irvine; Jeremy Darling of the University of Colorado; Baker; Luis C. Ho of the Kavli Institute for Astronomy and Astrophysics at Peking University in Beijing, China; and Jonelle L. Walsh of Texas A&M University.

    *Science paper:
    MEASUREMENT OF THE BLACK HOLE MASS IN NGC 1332 FROM ALMA OBSERVATIONS AT 0.044 ARCSECOND RESOLUTION

    See the full article here .

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    Rutgers, The State University of New Jersey, is a leading national research university and the state’s preeminent, comprehensive public institution of higher education. Rutgers is dedicated to teaching that meets the highest standards of excellence; to conducting research that breaks new ground; and to providing services, solutions, and clinical care that help individuals and the local, national, and global communities where they live.

    Founded in 1766, Rutgers teaches across the full educational spectrum: preschool to precollege; undergraduate to graduate; postdoctoral fellowships to residencies; and continuing education for professional and personal advancement.
    Rutgersensis

     
  • richardmitnick 8:14 am on June 1, 2016 Permalink | Reply
    Tags: , , , , ,   

    From Seeker at Discovery: “The Race to See Our Supermassive Black Hole” 

    Discovery News
    Discovery News

    1

    May 26, 2016
    No writer credit found.

    Using the power of interferometry, two astronomical projects are, for the first time, close to directly observing the black hole in the center of the Milky Way.

    Sag A*  NASA Chandra X-Ray Observatory 23 July 2014, the supermassive black hole at the center of the Milky Way
    Sag A* NASA Chandra X-Ray Observatory 23 July 2014, the supermassive black hole at the center of the Milky Way

    There’s a monster living in the center of the galaxy.

    We know the supermassive black hole is there by tracking the motions of stars and gas clouds that orbit an invisible point. That point exerts an overwhelming tidal influence on all objects that get trapped in its gravitational domain and this force can be measured through stellar orbits to calculate its mass.

    ESO VLT new laser
    ESO VLT new laser

    It certainly isn’t the biggest black hole in the universe, but it isn’t the smallest either, it “weighs in” at an incredible 4 million times the mass of our sun.

    But this black hole behemoth, called Sagittarius A*, is over 20,000 light-years from Earth making direct observations, before now, nigh-on impossible. Despite its huge mass, the black hole is minuscule when seen from Earth; a telescope with an unprecedented angular resolution is needed.

    Though we already know a lot about Sagittarius A* from indirect observations, seeing is believing and there’s an international race, using the world’s most powerful observatories and sophisticated astronomical techniques, to zoom-in on the Milky Way’s black hole. This won’t only prove it’s really there, but it will reveal a region where space-time is so warped that we will be able to make direct tests of general relativity in the strongest gravity environment known to exist in the universe.

    The Event Horizon Telescope and GRAVITY

    A huge global effort is currently under way to link a network of global radio telescopes to create a virtual telescope that will span the width of our planet. Using the incredible power of interferometry, astronomers can combine the light from many distant radio antennae and collect it at one point, to mimic one large radio antenna spanning the globe.

    A huge global effort is currently under way to link a network of global radio telescopes to create a virtual telescope that will span the width of our planet. Using the incredible power of interferometry, astronomers can combine the light from many distant radio antennae and collect it at one point, to mimic one large radio antenna spanning the globe.

    This effort is known as the Event Horizon Telescope (EHT) and it is hoped the project will be able to attain the angular resolution and spatial definition required to soon produce its first radio observations of the bright ring just beyond Sagittarius A*’s event horizon — the point surrounding a black hole where nothing, not even light, can escape.

    Event Horizon Telescope Array

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

    (ESO/APEX)
    Atacama Pathfinder EXperiment

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

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

    Caltech Submillimeter Observatory
    Caltech Submillimeter Observatory (CSO)

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

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

    Large Millimeter Telescope Alfonso Serrano
    Large Millimeter Telescope Alfonso Serrano

    CfA Submillimeter Array Hawaii SAO
    Submillimeter Array Hawaii SAO

    Future Array/Telescopes

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array, Chile

    Plateau de Bure interferometer
    Plateau de Bure interferometer

    South Pole Telescope SPTPOL
    South Pole Telescope SPTPOL

    However, another project has the same goal in mind, but it’s not going to observe in radio wavelengths, it’s going to stare deep into the galactic core to seek out optical and infrared light coming from Sagittarius A* and it just needs one observatory to make this goal a reality.

    The GRAVITY instrument is currently undergoing commissioning at the ESO’s Very Large Telescope at Paranal Observatory high in the Atacama Desert in Chile (at an altitude of over 2,600 meters or 8,300 ft) and it will also use the power of interferometry to resolve our supermassive black hole.

    ESO GRAVITY insrument
    ESO GRAVITY insrument

    But rather than connecting global observatories like the EHT, GRAVITY will combine the light of the four 8 meter telescopes of the VLT Interferometer (collectively known as the VLTI) to create a “virtual” telescope measuring the distance between each individual telescope.

    ESO VLTI image
    ESO VLTI image

    “By doing this you can reach the same resolution and precision that you would get from a telescope that has a size, in this case, of roughly a hundred meters, simply because these eight meter-class telescopes are separated by roughly one hundred meters,” astronomer Oliver Pfuhl, of Max Planck Institute for Extraterrestrial Physics, Germany, told DNews. “If you combine the light from those you reach the same resolution as a virtual telescope of a hundred meters would have.”

    Strong Gravity Environment

    When GRAVITY is online it will be used to track features just outside Sagittarius A*’s event horizon.

    “For about ten years, we’ve known that this black hole is actually not black. Once in awhile it flares, so we see it brightening and darkening,” he said. This flaring is matter falling into the event horizon, generating a powerful flash of energy. The nature of these flares are poorly understood, but the instrument should be able to track this flaring material as it rapidly orbits the event horizon and fades away. These flares will also act as tracers, helping us see the structure of space-time immediately surrounding a black hole for the first time.

    Our goal is to measure these motions. We think that what we see as this flaring is actually gas which spirals into the black hole. This brightening and darkening is essentially the gas, when it comes too close to the black hole, the strong tidal forces make it heat up,” said Pfuhl.

    “If we can study these motions which happen so close to the black hole, we have a direct probe of the space time close to the black hole. In this way we have a direct test of general relativity in one of the most extreme environments which you can find in the universe.”

    While GRAVITY will be able to track these flaring events very close to the black hole, the Event Horizon Telescope will see the shadow, or silhouette, of the dark event horizon surrounded by radio wave emissions. Both projects will be able to measure different components of the region directly surrounding the event horizon, so combined observations in optical and radio wavelengths will complement one other.

    It just so happens that the Atacama Large Millimeter/submillimeter Array (ALMA), the largest radio observatory on the planet — also located in the Atacama Desert — will also be added to the EHT.

    “The Event Horizon Telescope will combine ALMA with telescopes around the world like Hawaii and other locations, and with that power you can look at really fine details especially in the black hole in the center of our galaxy and perhaps in some really nearby other galaxies that also have black holes in their centers,” ESO astronomer Linda Watson told DNews.

    ALMA itself is an interferometer combining the collecting power of 66 radio antennae located atop Chajnantor plateau some 5,000 meters (16,400 ft) in altitude. Watson uses ALMA data to study the cold dust in interstellar space, but when added to the EHT, its radio-collecting power will help us understand the dynamics of the environment surrounding Sagittarius A*.

    “ALMA’s an interferometer with 66 antennas, (the EHT) will treat ALMA as just one telescope and will combine it with other telescopes around the world to be another interferometer,” she added.

    Black Hole Mysteries

    Many black holes are thought to possess an accretion disk of swirling gas and dust. ALMA, when combined with the EHT, will be able to measure this disk’s structure, speed and direction of motion. Lacking direct observations, many of these characteristics have only been modeled by computer simulations or inferred from indirect observations. We’re about to enter an era when we can truly get to answer some of the biggest mysteries surrounding black hole dynamics.

    “The first thing we want to see is we want to understand how accretion works close to the black hole,” said Pfuhl. “This is also true for the Event Horizon Telescope. Another thing we want to learn is does our black hole have spin? That means, does it rotate?”

    Though the EHT and GRAVITY are working at different wavelengths, observing phenomena around Sagittarius A* will reveal different things about the closest supermassive black hole to Earth. By extension it is hoped that we may observe smaller black holes in our galaxy and other supermassive black holes in neighboring galaxies.

    But as we patiently wait for the first direct observations of the black hole monster lurking in the center of our galaxy, an event that some scientists say will be as historic as the “Pale Blue Dot” photo of Earth as captured by Voyager 1 in 1990, it’s hard not to wonder which project will get there first.

    “I think it’s a very tight race,” said Pfuhl. “Let’s see.”

    See the full article here .

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  • richardmitnick 4:32 am on June 1, 2016 Permalink | Reply
    Tags: , , , , FAST, , SBS.com.au   

    From SBS via CSIRO: “In pictures: the building of world’s largest single dish telescope” 

    CSIRO bloc

    Commonwealth Scientific and Industrial Research Organisation

    2

    SBS

    6 May 2016 [CSIRO just put this up in social media]
    Signe Dean

    1
    A gigantic bowl of a telescope called FAST is under construction in China – and key components are being designed by CSIRO.

    For some of the residents of China’s Guizhou province the past six years have been colourful, to say the least. Here, in the Dawodang valley, in 2011 the Chinese Academy of Science began an immensely ambitious construction project for the world’s largest radio telescope.

    The Five-hundred-metre Aperture Spherical Telescope (FAST) which cost 1.27bn yuan (or $246m) is now getting to its final stages, with completion scheduled for later this year.

    It’s a gigantic bowl nestled in Guizhou’s Karst mountain range, a spectacular addition to already gorgeous natural scenery – and one that could tell us more about the universe than ever before.

    2
    Image courtesy NAOC

    Once functional, FAST will become not only the largest telescope of its kind on the whole planet, but also one of the most sensitive, able to receive more distant radio signals, and weak ones we may have previously missed.

    Astronomers are hoping this will be the tool to boost our search for intelligent life elsewhere in the galaxy and beyond – and also unveil more secrets about the origins of the universe.

    In an interview with South China Morning Post Chinese astronomer Shi Zhicheng said that “if intelligent aliens exist, the messages that they produced or left behind, if they are being transmitted through space, can be detected and received by FAST.”

    3
    Image courtesy NAOC

    At 500 metres in diameter, FAST is going to eclipse the current largest radio telescope in Arecibo, Puerto Rico, which stands at an impressive 300 metres.

    NAIC/Arecibo Observatory, Puerto Rico, USA
    NAIC/Arecibo Observatory, Puerto Rico, USA

    To create a 5-kilometre electromagnetic exclusion zone around the telescope, earlier this year China relocated more than 9,000 people, offering each of them a compensation of roughly $2500.

    Australian scientists have a hand in this project as well. China’s National Astronomical Observatories (NAOC) has teamed up with engineers from CSIRO to design and build one of the key components for FAST – a 19-beam receiver able to scan a large portion of the sky at a time, as opposed to most receivers used right now.

    4
    Image courtesy NAOC

    The reflector dish is made out of some 4,500 triangular panels which will be adjustable to form a curve corresponding to the segment of sky surveyed. As the radio signals are reflected, they will be transmitted to an Aussie-made receiver.

    “The powerful receiver we’ve created for FAST is the result of our long history developing cutting-edge astronomy technology to receive and amplify radio waves from space,” says Dr Douglas Bock, Acting Director of CSIRO Astronomy and Space Science.

    5
    Image courtesy NAOC

    “FAST will make it possible for us to look for a range of extremely interesting and exotic objects, like detecting thousands of new pulsars in our galaxy, and possibly the first radio pulsar in other galaxies,” says Professor Rendong Nan from NAOC.

    6
    Image courtesy NAOC

    And don’t forget – if we’re going to hear from aliens, FAST is our next best bet.

    See the full article here .

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    CSIRO campus

    CSIRO, the Commonwealth Scientific and Industrial Research Organisation, is Australia’s national science agency and one of the largest and most diverse research agencies in the world.

     
  • richardmitnick 5:45 pm on May 26, 2016 Permalink | Reply
    Tags: AIR & Space, , , , , , , ,   

    From Air & Space: “SETI Gets an Upgrade” 

    1

    Air & Space

    June 2016
    Damond Benningfield

    2
    The Green Bank radio telescope in West Virginia may pull in an alien signal. (Jiuguang Wang)

    Dan Werthimer doesn’t mean to be rude, but he’s getting ready to eavesdrop on the neighbors.

    For decades, astronomers have been listening for messages sent to us—a “Hello, is anyone out there?” signal from intelligent aliens. But now Werthimer is about to get nosier; his team at the University of California at Berkeley is conducting the first search for communities on other worlds that are speaking to one another—between planets and even across star systems. And to do it, he has two of the world’s largest radio telescopes and support from a planet‑hunting optical telescope.

    Thanks to a new initiative announced last July, Werthimer’s team will begin searching for extraterrestrial civilizations, using instruments with greater sensitivity and scanning across a wider range of frequencies than any SETI (search for extraterrestrial intelligence) project to date. Called Breakthrough Listen, it began earlier this year and will continue for a decade at a price tag of $100 million. “It’s a lot of money, a lot of telescope time,” says Werthimer. “We’ll be able to look at a hundred billion radio channels simultaneously. A big problem in SETI is we don’t know on what frequency ET might be transmitting, so the more channels you can listen to, the better chance you have of finding” a communication.

    It’s an incredibly exciting time scientifically,” adds Werthimer’s colleague Andrew Siemion, director of Berkeley’s SETI Research Center and another Breakthrough Listen leader. “Something like one in five stars has an Earth-like planet…. And our ability to look for different kinds of signals from intelligent civilizations on those planets is growing by leaps and bounds.”

    3
    Andrew Siemion eyed the Green Bank Telescope, in the 13,000 square-mile National Radio Quiet Zone, as ideal for SETI research in 2010. (Dr. Andrew P.V. Siemion)

    Even with improvements in technology, though, SETI has remained a tiny area within the field of radio astronomy. “In the entire world, there are probably fewer than 12 people who do full-time SETI research,” according to Seth Shostak, a senior astronomer for the SETI Institute in nearby Mountain View.

    But that small cadre of researchers, with the help of a few dozen part-time SETI dabblers, has plowed through an impressive number of projects. They have scanned the skies at radio and optical wavelengths for intentional messages from other civilizations. Researchers have picked through data from NASA’s planet-hunting Kepler space telescope for evidence of vast architecture eclipsing part of a star’s light. (The public release of one star’s odd light curve last year generated a round of speculation about alien mega-structures. Sadly, followup observations have suggested that the more likely explanation is a swarm of comets.) And they’ve looked for super-civilizations producing copious amounts of waste heat in the form of infrared energy. And the ideas never stop coming: There is a proposal to search for alien probes and artifacts in the solar system (possible payoffs but expensive) and another to listen for signals in beams of neutrinos or the recently discovered gravitational waves (far beyond current technology).

    The bottleneck is never a lack of ideas,” says Shostak. “The problem has always been funding.”

    From the first search for extraterrestrial signals—Frank Drake’s Project Ozma in 1960—SETI has struggled to be taken seriously by traditional funding agencies. Modest NASA studies in the 1970s and 1980s were criticized by the U.S. Congress; in 1993, legislators axed what was meant to be NASA’s long-term sky survey after just a year. Since then the field has survived, barely, primarily on private funding sources.

    Then last summer, Russian billionaire Yuri Milner announced he would foot the bill for the biggest alien hunt in history. “In the 20th century, we stepped out from our planet—to space, to the moon, to the solar system,” Milner said at a press conference for Breakthrough Listen last summer. “In the 21st century, we will find out about life on a galactic scale…. It is time to open our eyes, our ears, and our minds to the cosmos.” Among the luminaries endorsing Milner’s project that day was astrophysicist Stephen Hawking.

    Milner, named after first-human-in-space Yuri Gagarin, was studying physics at Moscow University in the 1980s when the entrepreneurial spirit first hit him. He started buying American-made personal computers and reselling them in local shops, then ventured to the United States to get an MBA. After briefly working at the World Bank, he returned to Russia and began investing in businesses, parlaying the purchase of a small factory into the takeover of the country’s largest Internet company. With that move as an entry to the world of technology, Milner organized a venture capital fund, DST Global, which became an early investor in Facebook, then Twitter, Groupon, and Airbnb, along with major companies in India and China. According to Forbes, by the end of 2015 Milner amassed a net worth of $3.3 billion. In happy news for non-billionaire scientists, Milner started a foundation in 2012 that awards three $3 million prizes annually—the largest academic prize in the world—for achievements in fundamental physics, life sciences, and mathematics.

    He also refuses to give interviews about his latest investment, so we can get a sense of his intentions only from the people now running the Breakthrough Listen project. “He studied physics, he studied the same kind of books in school that I did, so he knows a lot about SETI,” says Werthimer. “He really appreciates all the subtle nuances, and he asks a lot of great questions. He knows the chances that we might find something are slim. But he speaks about this in the long term. He’s in it for the long haul.”

    4
    The Nickel Telescope at California’s Lick Observatory (with SETI’s Dan Werthimer, second from left) will look for lasers. Being used in the Niroseti project (Laurie Hatch)

    Werthimer was already in it for the long haul—he’s been working on SETI for decades, although his original love was the hardware, rather than the research. He’s been a tech junkie since his school days, when he joined the Homebrew Computer Club in California, where his fellow members included Apple founders Steve Jobs and Steve Wozniak. “We were kind of messing around in our basements, and we made the very first desktop,” Werthimer says. “Everybody in that club got filthy rich except for me, because I wanted to use the computers to do astronomy. But I got really good at computing. I built a lot of cool machines that were in some ways better than the Apple, but I never thought about selling them.”

    Werthimer began to build instruments that collect and analyze radio signals from space, and eventually started SETI@Home in 1999, a program that harnesses the background processing power of any computer it’s installed on to help sift through portions of the massive amounts of data from the Arecibo Observatory in Puerto Rico.

    SETI@home, BOINC project at UC Berkeley Space Science Lab
    SETI@home, BOINC project at UC Berkeley Space Science Lab

    NAIC/Arecibo Observatory, Puerto Rico, USA
    NAIC/Arecibo Observatory, Puerto Rico, USA

    And although his work hasn’t revealed any alien civilizations, Werthimer isn’t bothered by the silence. “I wouldn’t be in this field if I were not an optimist,” he says. “We’ve covered maybe a billionth of the parameter space. We can rule out super-civilizations that want to conquer the galaxy”—whew—“but we can’t rule out civilizations like ours.”

    Siemion too developed an early interest in science and technology. “I did a report when I was in third grade on a book by Stephen Hawking, A Brief History of Time,” he says. “When I got to Berkeley I was looking over possible research opportunities, and I discovered that there was a SETI group. I had an ‘aha’ moment—I knew immediately that that’s what I would do.”

    Siemion led his first SETI project while he was still a graduate student. He got the idea in 2010, while he was attending a meeting at the Robert C. Byrd Green Bank Telescope in West Virginia to commemorate the 50th anniversary of Project Ozma. Attendees were re-creating Ozma, which originally used a small radio antenna at the Green Bank location, with the observatory’s new 300-foot-diameter Green Bank Telescope, the largest fully steerable radio telescope in the world. While Ozma took about 150 hours of telescope time, the re-creation required only a few seconds to scan the same amount of sky.

    “I started thinking: Why not do some real SETI with the telescope,” Siemion says. “On the plane back to San Francisco, I met in the aisle with a few other people, and we decided to write a proposal.” The idea was to look at star systems in which the Kepler space telescope had discovered planets. “We actually received not the best grade from the time allocation committee at Green Bank,” he says. “They gave us a C, because I think they were a little bit suspicious about whether we would actually be able to do it, but luckily, even though it wasn’t highly ranked, we still got the time.”

    Breakthrough Listen will take advantage of the data from Siemion’s work with Green Bank, but more importantly, it comes at a crucial time for the observatory. Constructed in a valley in the West Virginia mountains, the Green Bank Telescope opened in 2000 as part of the National Radio Astronomy Observatory. NRAO is funded by the National Science Foundation and runs several facilities, including the Very Large Array in New Mexico and the Atacama Large Millimeter/Submillimeter Array, or ALMA, in Chile (“The Universe’s Baby Boom,” Aug. 2013).

    NRAO/VLA, on the Plains of San Agustin fifty miles west of Socorro, New Mexico.
    NRAO/VLA, on the Plains of San Agustin fifty miles west of Socorro, New Mexico

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array

    But in 2012, NSF issued a report on the next 10 years of astronomy research that recommended pulling Green Bank’s funding by 2017, because some of its research abilities are duplicated at larger facilities like the VLA and Arecibo Observatory. Now SETI—usually the research area struggling for funding—has come along with Breakthrough Listen at just the right moment, providing a reason and the means to keep the telescope operating while its staff looks for additional funding.

    5
    Russian billionaire Yuri Milner announces Breakthrough Listen last July alongside Stephen Hawking, Martin Rees, Frank Drake, and Ann Druyan. (Breakthrough Initiatives)

    One of Green Bank’s advantages is that it’s cocooned in the 13,000-square-mile National Radio Quiet Zone, where radio transmitters, cellphone towers, wifi networks, and other technology are limited by state and federal regulations. Scientists there would have an easier time determining if a signal in their observations is a message from another planet rather than a local teenager’s text. “One of the hardest things to do is tease out a signal from another civilization in the radio observations,” says Karen O’Neil, the Green Bank Observatory site director. “There are a lot of repeating patterns, but they’re all man-made.”

    Green Bank’s receivers are so sensitive they can detect the crackle of spark plugs in a gasoline-powered engine, so only diesel vehicles are allowed within a mile of the dish. The microwave oven in the observatory’s cafeteria sits inside a shielded box, and once the telescope even picked up interference from a small current generated by a wet dog lying down on an old heating pad. Staff members drive around in a pickup truck equipped with scanning equipment to track down stray electromagnetic signals, and sometimes lend a hand to help repair or replace offending devices in nearby businesses and homes.

    SETI is using some of the project funding to expand Green Bank’s computer capabilities far beyond those of any previous radio SETI project. The system will be able to process and store as much data in a single day as existing projects do in a year or more. Then it’s sent out to the SETI team at Berkeley and SETI@Home volunteers for analysis. The extra processing and storage capabilities are necessary because Breakthrough Listen will scan billions of radio channels between 1 and 10 gigahertz. Earlier surveys have been able to scan no more than a few hundred million channels at a time, with about half the spectral range. “We probably have a trillion times better capabilities today than when I started 40 years ago,” says Werthimer.

    That sensitivity should allow the telescopes to pick up intelligent signals not meant for us, something that couldn’t have been done before the Kepler mission provided astronomers with exoplanet locations. “There’s speculation that an advanced civilization might colonize another planet in its own solar system, like we might do with Mars,” says Werthimer. “They might send messages back and forth between planets, and we could pick up the signals when they line up with Earth.” In addition to the nearest million stars to Earth, the SETI group will monitor the densely packed center of the Milky Way galaxy, about 27,000 light-years away. “Our solar system is about five billion years old,” says Werthimer. “Some stars are 10 billion years old, so there could be some very advanced civilizations out there.” And finally, Breakthrough Listen will stretch its search out even farther, to 100 nearby galaxies where super-civilizations might be blasting messages between solar systems.

    7
    SETI will tune into Planet -452b (concept opposite) and other exoplanets found by NASA’s Kepler. (NASA/JPL-Caltech/T. Pyle)

    While the Green Bank Telescope searches in the northern hemisphere, Breakthrough Listen will use the Parkes Telescope near Sydney, Australia, to search the southern sky. The 210-foot movable dish is best known for transmitting most of the Apollo 11 moon landing video for the worldwide television broadcast (the event was fictionalized in the 2000 movie The Dish). The project will use about 20 percent of the observing time on each telescope, a jump from the few dozen cumulative hours SETI usually gets annually to thousands of hours.

    The third facility SETI is using will look instead of listen. The Automated Planet Finder, a 96-inch optical telescope at Lick Observatory, outside San Jose, California, will devote 10 percent of its time to searching for interstellar lasers.

    Lick Automated Planet Finder telescope
    Lick Automated Planet Finder telescope

    “If we took our own highest-powered lasers and paired them with our largest telescopes, we could send a beam that would outshine the sun by a factor of 10 at a distance of 1,000 light-years,” says Siemion. “Perhaps other civilizations are doing that to contact other civilizations, or to transmit a large amount of information.” It would be the equivalent of a Galaxy Wide Web.

    8
    The Parkes Observatory in Australia (opposite) is Breakthrough Listen’s outpost to eavesdrop on alien communication between star systems. (Daniel Sallai)

    Of course, not everyone is optimistic about the chances of Breakthrough Listen or any other SETI project finding evidence of neighboring civilizations, but not necessarily because they don’t believe in aliens. “Listening for intentional messages seems like a lost cause,” says Paul Davies, a researcher at Arizona State University and author of The Eerie Silence, a book that posits that current searches for intelligent life are flawed. “I’ve argued that we should be looking for other things: beacons, or probes, or alien artifacts in our own solar system. We have no idea how a super-civilization would manifest itself. It could be genetic—we could find signs in terrestrial biology…. There’s a good chance we might be alone in the universe. So we should search, but we shouldn’t spend a lot of money on it.”

    Even Werthimer doesn’t expect to hear from extraterrestrials anytime soon. “I’m optimistic in the long run,” he says. “We Earthlings are a young, emerging civilization. We’re just getting in the game, so a thorough search will take a while…. We probably won’t see anything in the next 10 years, so we’ll have to devise a new plan after that. Maybe, if the trend in computing power keeps going, we’ll find ET in 30 years.”

    In the meantime, let the eavesdropping begin.

    See the full article here.

    Prelude to the Breakthrough Project

    UC Santa Cruz
    From UCO Lick
    March 23, 2015

    Hilary Lebow

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    8
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch)

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    4
    UCSC alumna Shelley Wright, now an assistant professor of physics at UC San Diego, discusses the dichroic filter of the NIROSETI instrument. (Photo by Laurie Hatch)

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

    See the full article here.

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  • richardmitnick 9:44 am on May 25, 2016 Permalink | Reply
    Tags: , ALMA Reveals Footprints of Baby Planets in a Gas Disk, , , ,   

    From ALMA: “ALMA Reveals Footprints of Baby Planets in a Gas Disk” 

    ALMA Array

    ALMA

    24 May 2016
    Nicolás Lira T.
    Education and Public Outreach Coordinator
    Joint ALMA Observatory
    Santiago, Chile
    Tel: +56 2 24 67 65 19
    Cell: +56 9 94 45 77 26
    Email: nicolas.lira@alma.cl

    Masaaki Hiramatsu

    Education and Public Outreach Officer, NAOJ Chile
    Observatory
Tokyo, Japan

    Tel: +81 422 34 3630

    E-mail: hiramatsu.masaaki@nao.ac.jp

    Richard Hook
    Public Information Officer, ESO

    Garching bei München, Germany

    Tel: +49 89 3200 6655

    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    Charles E. Blue
    Public Information Officer
    National Radio Astronomy Observatory
    Charlottesville, Virginia, USA
    Tel: +1 434 296 0314
    Cell: +1 202 236 6324
    E-mail: cblue@nrao.edu

    New analysis of ALMA data for HL Tauri provides yet more firm evidence of baby planets around the star. Researchers uncovered two gaps in the gas disk around the star. The locations of these gaps in the gas match the locations of gaps in the dust found in the ALMA high resolution image taken in 2014. This discovery supports the idea that planets form in much shorter timescales than previously thought and prompts a reconsideration of alternative planet formation scenarios.

    In November 2014, ALMA released a startling image of HL Tauri and its dust disk. This image, the sharpest ever taken for this kind of object, clearly depicts several gaps in the dust disk around the star.

    1
    Figure 1. ALMA image of the dust disk around HL Tauri. Credit: ALMA (ESO/NAOJ/NRAO)

    Astronomers have not yet reached a definitive answer for what makes the gaps in the dust disk. Because these disks are the sites of planet formation, some suggest that infant planets are the key; the dark gaps are carved by planets forming in the disk that attract or sweep away the dust along their orbits.

    But others doubt the planet explanation because HL Tauri is very young, estimated to be only about a million years, and classical studies indicate that it takes more than tens of millions of years for planets to form from small dust. Those researchers propose other possible mechanisms to form the gaps: changes in the dust size through coalescence or destruction; or the formation of dust due to gas molecules freezing.

    More data was needed to determine which theory is correct. We know that the disks around young stars contain gas in addition to the dust. In fact, in general the amount of gas is 100 times larger than that of dust. The research team led by Dr. Hsi-Wei Yen at Academia Sinica Institute of Astronomy and Astrophysics in Taiwan and Professor Shigehisa Takakuwa at Kagoshima University, Japan, focused on the distribution of gas in the disk to better understand the true nature of the disk. If the dust gaps are caused by the variance of the dust properties, that wouldn’t directly affect the gas, so no gaps would be seen in the gas distribution. If on the other hand, the gaps in the dust are caused by the gravity of forming planets, the gravity would be expected to created gaps in the gas as well.

    Even with ALMA’s unprecedented sensitivity, it was not easy to reveal the distribution of gas in the disk. The team extracted the emissions from HCO+ gas molecules in the publicly available 2014 ALMA Long Baseline Campaign data and summed up the emissions in rings around the star to increase the effective sensitivity. This novel data analysis technique yielded the sharpest image ever of the gas distribution around a young star.

    The image of HCO+ distribution reveals at least two gaps in the disk, at the radii of 28 and 69 astronomical units. “To our surprise, these gaps in the gas overlap with the dust gaps,” said Yen, the lead author of the paper that appeared in the Astrophysical Journal Letters. “This supports the idea that the gaps are the footprints left by baby planets.” The fact that the gaps in the dust and the gas match-up implies that the amount of material in the gaps likely decreases. This disfavors some of the theories that tried to explain the gaps solely by changes in the dust particles. A decrease in the amount of material in the gaps supports the planet formation theory, in spite of HL Tauri’s young age. “Our results indicate that planets start to form much earlier than what we expected.” Yen added.

    2
    Figure 2. HCO+ gas (blue) and dust (red) distributions in the disk around HL Tauri. The ellipses show the locations of the gaps. Credit: ALMA (ESO/NAOJ/NRAO), Yen et al.

    3
    Figure 3. Artist’s concept of HL Tauri. The star is surrounded by the disk (shown in red) and thick envelope. The star ejects a bipolar collimated jet. Credit: ASIAA

    The team also found that the gas density is high enough to harbor an infant planet around the inner gap. Comparing the structure of the inner gap to theoretical models, the team estimates the planet has a mass 0.8 times that of Jupiter.

    On the other hand, the origin of the outer gap is still unclear. The team suggested the possible existence of a planet 2.1 times more massive than Jupiter, but the present research cannot eliminate the possibility that the gap is made by the drag between the dust particles and the gas. To solve this question, more data are needed.

    “Our research clearly demonstrates that applying new data analysis techniques to existing data can uncover important facts, further increasing ALMA’s already high scientific potential,” commented Takakuwa. “Applying the same method to the datasets for other young stars, we expect to construct a systematic model of planet formation.”

    Additional information

    These observation results were published as Yen et al. Gas Gaps in the Protoplanetary Disk around the Young Protostar HL Tau in the Astrophysical Journal Letters, issued in April 2016.

    The research team members are:

    Hsi-Wei Yen (Academia Sinica Institute of Astronomy and Astrophysics, Taiwan), Hauyu Baobab Liu (European Southern Observatory, Germany), Pin-Gao Gu, Naomi Hirano, Chin Fei Lee (Academia Sinica Institute of Astronomy and Astrophysics, Taiwan), Evaria Puspitaningrum (Institut Teknologi Bandung, Indonesia) and Shigehisa Takakuwa (Kagoshima University, Japan).

    This research is supported by the Ministry of Science and Technology, Taiwan.

    See the full article here .

    Please help promote STEM in your local schools.
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    The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Academia Sinica (AS) in Taiwan.

    ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI) and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

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