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  • richardmitnick 2:41 pm on April 12, 2017 Permalink | Reply
    Tags: , , , , , , Planetary body 2014 UZ224 more informally known as DeeDee, Radio Astronomy   

    From ALMA: “ALMA Investigates ‘DeeDee,’ a Distant, Dim Member of Our Solar System” 

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres
    ALMA

    April 12, 2017
    Nicolás Lira T.
    Press 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
    Artist concept of the planetary body 2014 UZ224, more informally known as DeeDee. ALMA was able to observe the faint millimeter-wavelength “glow” emitted by the object, confirming it is roughly 635 kilometers across. At this size, DeeDee should have enough mass to be spherical, the criterion necessary for astronomers to consider it a dwarf planet, though it has yet to receive that official designation. Credit: Alexandra Angelich (NRAO/AUI/NSF)

    Using the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers have revealed extraordinary details about a recently discovered far-flung member of our solar system, the planetary body 2014 UZ224, more informally known as DeeDee.

    2
    ALMA image of the faint millimeter-wavelength “glow” from the planetary body 2014 UZ224, more informally known as DeeDee. At three times the distance of Pluto from the Sun, DeeDee is the second most distant known TNO with a confirmed orbit in our solar system. Credit: ALMA (ESO/NAOJ/NRAO)

    At about three times the current distance of Pluto from the Sun, DeeDee is the second most distant known trans-Neptunian object (TNO) with a confirmed orbit, surpassed only by the dwarf planet Eris. Astronomers estimate that there are tens-of-thousands of these icy bodies in the outer solar system beyond the orbit of Neptune.

    The new ALMA data reveal, for the first time, that DeeDee is roughly 635 kilometers across, or about two-thirds the diameter of the dwarf planet Ceres, the largest member of our asteroid belt. At this size, DeeDee should have enough mass to be spherical, the criterion necessary for astronomers to consider it a dwarf planet, though it has yet to receive that official designation.

    “Far beyond Pluto is a region surprisingly rich with planetary bodies. Some are quite small but others have sizes to rival Pluto, and could possibly be much larger,” said David Gerdes, a scientist with the University of Michigan and lead author on a paper appearing in the Astrophysical Journal Letters. “Because these objects are so distant and dim, it’s incredibly difficult to even detect them, let alone study them in any detail. ALMA, however, has unique capabilities that enabled us to learn exciting details about these distant worlds.”

    Currently, DeeDee is about 92 astronomical units (AU) from the Sun. An astronomical unit is the average distance from the Earth to the Sun, or about 150 million kilometers. At this tremendous distance, it takes DeeDee more than 1,100 years to complete one orbit. Light from DeeDee takes nearly 13 hours to reach Earth.

    Gerdes and his team announced the discovery of DeeDee in the fall of 2016. They found it using the 4-meter Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile as part of ongoing observations for the Dark Energy Survey, an optical survey of about 12 percent of the sky that seeks to understand the as-yet mysterious force that is accelerating the expansion of the universe.

    The Dark Energy Survey produces vast troves of astronomical images, which give astronomers the opportunity to also search for distant solar system objects.

    The initial search, which includes nearly 15,000 images, identified more than 1.1 billion candidate objects. The vast majority of these turned out to be background stars and even more distant galaxies. A small fraction, however, were observed to move slowly across the sky over successive observations, the telltale sign of a TNO.

    One such object was identified on 12 separate images. The astronomers informally dubbed it DeeDee, which is short for Distant Dwarf.

    The optical data from the Blanco telescope enabled the astronomers to measure DeeDee’s distance and orbital properties, but they were unable to determine its size or other physical characteristics. It was possible that DeeDee was a relatively small member of our solar system, yet reflective enough to be detected from Earth. Or, it could be uncommonly large and dark, reflecting only a tiny portion of the feeble sunlight that reaches it; both scenarios would produce identical optical data.

    Since ALMA observes the cold, dark universe, it is able to detect the heat – in the form of millimeter-wavelength light – emitted naturally by cold objects in space. The heat signature from a distant solar system object would be directly proportional to its size.

    “We calculated that this object would be incredibly cold, only about 30 degrees Kelvin, just a little above absolute zero,” said Gerdes.

    While the reflected visible light from DeeDee is only about as bright as a candle seen halfway the distance to the moon, ALMA was able to quickly home in on the planetary body’s heat signature and measure its brightness in millimeter-wavelength light.

    This allowed astronomers to determine that it reflects only about 13 percent of the sunlight that hits it. That is about the same reflectivity of the dry dirt found on a baseball infield.

    By comparing these ALMA observations to the earlier optical data, the astronomers had the information necessary to calculate the object’s size. “ALMA picked it up fairly easily,” said Gerdes. “We were then able to resolve the ambiguity we had with the optical data alone.”

    Objects like DeeDee are cosmic leftovers from the formation of the solar system. Their orbits and physical properties reveal important details about the formation of planets, including Earth.

    This discovery is also exciting because it shows that it is possible to detect very distant, slowly moving objects in our own solar system. The researchers note that these same techniques could be used to detect the hypothesized “Planet Nine” that may reside far beyond DeeDee and Eris.

    “There are still new worlds to discover in our own cosmic backyard,” concludes Gerdes. “The solar system is a rich and complicated place.”

    3

    Orbits of objects in our solar system, showing the current location of the planetary body ‘DeeDee’.
    Credit: Alexandra Angelich (NRAO/AUI/NSF)

    Additional information

    This research is presented in a paper titled “Discovery and physical characterization of a large scattered disk object at 92 AU,” appearing in the Astrophysical Journal Letters.

    The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

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

    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

    GBO radio telescope, Green Bank, West Virginia, USA
    Green Bank Observatory radio telescope, Green Bank, West Virginia, USA, formerly supported by NSF, but now on its own
    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 3:40 pm on April 10, 2017 Permalink | Reply
    Tags: , , , , Radio Astronomy,   

    From NJIT: Putting Students Closer to Explosive Solar Events 

    NJIT Bloc

    New Jersey Institute of Technology

    1

    April 6, 2017

    NJIT has a long-established reputation as a leader in researching phenomena originating on the star closest to Earth — the Sun. NJIT’s optical telescope at Big Bear Solar Observatory and radio telescope array at Owens Valley, both in California, have greatly expanded our understanding of solar events that periodically impact our home planet, events such as solar flares and coronal mass ejections (CMEs) that can disrupt terrestrial communications and power infrastructure in addition to other effects.

    NJIT Big Bear Solar Observatory, located on the north side of Big Bear Lake in the San Bernardino Mountains of southwestern San Bernardino County, California, approximately 120 kilometers east of downtown Los Angeles

    Ten antennas of NJIT’s 13-antenna Expanded Owens Valley Solar Array (EOVSA)

    Under the auspices of the university’s Center for Solar-Terrestrial Research (CSTR), NJIT investigators are collaborating with colleagues in the U.S. and other countries to gain even more critical knowledge of solar physics. It’s knowledge essential not only for better basic understanding of the Sun but also to improve prediction of the solar explosions that threaten our technologies and to devise better countermeasures.

    What’s more, NJIT researchers are committed to fully engaging students in the search for this knowledge — researchers like Assistant Professor of Physics Bin Chen, who joined the NJIT faculty in 2016. Chen was recently awarded a five-year CAREER grant totaling more than $700,000 by the National Science Foundation (NSF). The NSF’s Faculty Early Career Development (CAREER) program offers the foundation’s most prestigious awards in support of younger faculty who, in building their academic careers, have demonstrated outstanding potential as both educators and researchers.

    Chen completed his Ph.D. at the University of Virginia in 2013 with a focus on solar radio astronomy. His Ph.D. advisor introduced him to fellow solar astronomer, and now NJIT colleague, Distinguished Professor of Physics Dale Gary. Through his acquaintance with Gary, and the opportunity to collaborate on a research project using observational data from NJIT’s Owens Valley Solar Array, Chen learned about the university’s leading-edge efforts in solar radio physics. But before he joined NJIT after receiving his doctorate, Chen added to his research experience through a postdoctoral fellowship under NASA’s Living With a Star program and as an astrophysicist at the Harvard Smithsonian Center for Astrophysics, where he worked on space missions dedicated primarily to solar science.

    Shocking Insights

    Although not yet fellow faculty members at NJIT, Chen and Gary did collaborate with researchers from the National Radio Astronomy Observatory, the University of California, the University of Applied Sciences and Arts Northwestern Switzerland and the University of Minnesota on an article for the journal Science published in 2015, Particle Acceleration by a Solar Flare Termination Shock. The article presented radio imaging data that provides new insights into how a phenomenon known as termination shock associated with solar flares, the most powerful explosions in the solar system, helps to accelerate energetic electrons in the flares to relativistic speeds — propelling these particles into space at nearly the speed of light.

    Chen is now continuing this investigation at NJIT. “There is a lot we don’t know about the ‘inside’ of these solar explosions and how they release so much energy so quickly and so catastrophically,” he says. “For example, how is the energy stored and suddenly released, often in a matter of seconds?

    “The relativistic particle acceleration that we are also studying as part of this research is a process taking place across the universe and is a phenomenon associated with, for example, the massive star explosions known as supernovae. The Sun is a good place to research this phenomenon because its nearness in astronomical terms allows us to acquire a volume of high-resolution data impossible to obtain from observing vastly more distant stars.”

    For his research, Chen is drawing on streams of radio data from a number of sources. In addition to NJIT’s radio observatory at Owens Valley, these include the Karl G. Jansky Very Large Array in New Mexico operated by the National Radio Astronomy Observatory and the Atacama Large Millimeter/Submillimeter Array in Chile.

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

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    Recent upgrades at Owens Valley put it at the forefront of this research as a “new-generation” radio telescope. Another very important advantage afforded by Owens Valley, as Chen emphasizes, is that it is a facility dedicated full-time to solar research.

    Chen is one of the few researchers seeking new knowledge of the Sun by taking advantage of an observing technique called dynamic spectroscopy imaging. This technique allows capturing an image of the Sun every 50 milliseconds at more than a thousand frequencies, and at two different polarizations. This adds up to 40,000 images per second and terabytes of raw data in a day that can be converted into 3D images with resolution far greater than previously obtainable. “This gives us the potential to learn so much more about what is going on in the heart of solar explosions,” Chen says.

    Beyond greater understanding of the fundamental physics involved, Chen adds that his research is very much supportive of the goals of the U.S. National Space Weather Strategy and Action Plan, which reflects critical awareness of how space weather generated by solar phenomena impacts many aspects of terrestrial life and infrastructure. He says, “Solar flares and CMEs are the main drivers of space weather. Better understanding of these drivers is essential for better prediction of such events and the implementation of protective measures.”

    Bringing the Sun to Campus

    In Chen’s estimation, NJIT is uniquely experienced in building, operating and maintaining facilities dedicated to radio observation of the Sun. Potentially, for students, this presents exceptional opportunities to learn at the frontier of the many disciplines relevant to investigating the Sun in the radio spectrum — including hands-on familiarity with the equipment involved. While a limited number of students do have a chance to work at Owens Valley, as well as at Big Bear, distance and lack of appropriate accommodations prevent many more from participating in solar research on site. That’s why Chen also plans to apply a portion of his CAREER funding to creating a Solar Radio Laboratory on campus in Newark.

    “The idea behind the Solar Radio Laboratory is to have a facility on campus with the same state-of-the-art technology found at Owens Valley, just without the antennas,” Chen explains. “We’ll have all the electronics, the radio technology, the data-science capability for processing data streaming from California. This will give students the same hands-on opportunities for working and experimenting with the instrumentation that NJIT has at Owens Valley, instrumentation that is really unique in the United States. Another goal is to use this as a test bed for future improvements at Owens Valley, and to engage students in developing those improvements.”

    For Chen, a complementary educational goal is to also advance the Hale COLLAborative Graduate Education (COLLAGE) program in solar physics, which commemorates the name of the pioneering American solar astronomer George Ellery Hale. There are very few graduate programs in this field in the U.S. and the necessary faculty and physical resources are widely distributed across educational institutions as well as geography. To address this situation, Philip Goode, NJIT distinguished research professor of physics and former CSTR director, proposed that NJIT join with the University of Colorado-Boulder and several other institutions that had solar physics programs in what is now known as the COLLAGE program.

    “COLLAGE gives more students in different parts of the country access to the instruction and resources that allow them to complete master’s and Ph.D. degrees in solar physics,” Chen says. “I am already working with some 20 students, and that’s actually quite a large number for our field. But not only are we increasing opportunities to study solar physics at the graduate level, we’re learning more about coordinating resources among schools and teaching effectively online, which will benefit students who want to study many different complex subjects.”

    See the full article here .

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    NJIT campus

    Welcome to the New Jersey Institute of Technology. We’re proud of our 130 years of history, but that’s only the beginning of our story – we’ve doubled the size of our campus in the last decade, pouring millions into major new research facilities to give our students the edge they need in today’s demanding high-tech marketplace.

    NJIT offers 125 undergraduate and graduate degree programs in six specialized schools instructed by expert faculty, 98 percent of whom hold the highest degree in their field.

    Our academic programs are fully accredited by the appropriate accrediting boards, commissions and associations such as Middle States, ABET, and NAAB.

     
  • richardmitnick 2:13 pm on April 5, 2017 Permalink | Reply
    Tags: , , Radio Astronomy, Spring Cleaning in an Infant Star System   

    From ALMA: “Spring Cleaning in an Infant Star System” 

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres
    ALMA

    03 April 2017
    Nicolás Lira T.
    Press 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

    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

    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

    1
    Credit: ALMA (ESO/NAOJ/NRAO)/ Fedele et al.

    This image depicts the dusty disc encircling the young, isolated star HD 169142. The Atacama Large Millimeter/submillimeter Array (ALMA) imaged this disc in high resolution by picking up faint signals from its constituent millimetre-sized dust grains. The vivid rings are thick bands of dust, separated by deep gaps.

    Optimised to study the cold gas and dust of systems like HD 169142, ALMA’s sharp eyes have revealed the structure of many infant solar systems with similar cavities and gaps. A variety of theories have been proposed to explain them — such as turbulence caused by magnetorotational instability, or the fusing of dust grains — but the most plausible explanation is that these pronounced gaps were carved out by giant protoplanets.

    When solar systems form gas and dust coalesce into planets. These planets then effectively spring clean their orbits, clearing them of gas and dust and herding the remaining material into well-defined bands. The deep gaps seen in this image are consistent with the presence of multiple protoplanets — a finding that agrees with other optical and infrared studies of the same system.

    Observing such dusty protoplanetary discs with ALMA allows scientists to investigate the first steps of planet formation in a bid to unveil the evolutionary paths of these infant systems.

    See the full article here .

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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.

    NRAO Small
    ESO 50 Large
    NAOJ

     
  • richardmitnick 5:51 pm on April 4, 2017 Permalink | Reply
    Tags: , , , , , , Radio Astronomy,   

    From Swinburne: “Mysterious bursts of energy do come from outer space” 

    Swinburne U bloc

    Swinburne University

    1
    Artist’s impression shows three bright red flashes depicting fast radio bursts far beyond the Milky Way, appearing in the constellations Puppis and Hydra. Credit: James Josephides/Mike Dalley.

    3 April 2017
    Lea Kivivali
    +61 3 9214 5428
    lkivivali@swin.edu.au

    Fast Radio Bursts present one of modern astronomy’s greatest mysteries: what or who in the Universe is transmitting short bursts of radio energy across the cosmos?

    Manisha Caleb, a PhD candidate at Australian National University, Swinburne University of Technology and the ARC Centre of Excellence for All-sky Astrophysics (CAASTRO), has confirmed that the mystery bursts of radio waves that astronomers have hunted for ten years really do come from outer space.

    Ms Caleb worked with Swinburne and University of Sydney colleagues to detect three of these Fast Radio Bursts (FRBs) with the Molonglo radio telescope 40 km from Canberra.

    U Sidney Molonglo Observatory Synthesis Telescope (MOST), Hoskinstown, Australia

    Discovered almost 10 years ago at CSIRO’s Parkes radio telescope, Fast Radio Bursts are millisecond-duration intense pulses of radio light that appear to be coming from vast distances.

    CSIRO/Parkes Observatory, located 20 kilometres north of the town of Parkes, New South Wales, Australia

    They are about a billion times more luminous than anything we have ever seen in our own Milky Way galaxy.

    One potential explanation of the mystery is that they weren’t really coming from outer space, but were some form of local interference tricking astronomers into searching for new theories of their ‘impossible’ radio energy.

    “Perhaps the most bizarre explanation for the FRBs is that they were alien transmissions,” says ARC Laureate Fellow Professor Matthew Bailes from Swinburne.

    “Conventional single dish radio telescopes have difficulty establishing that transmissions originate beyond the Earth’s atmosphere,” says Swinburne’s Dr Chris Flynn.

    Molonglo opens new window on the Universe

    In 2013 CAASTRO scientists and engineers realised that the Molonglo telescope’s unique architecture could place a minimum distance to the FRBs due to its enormous focal length. A massive re-engineering effort began, which is now opening a new window on the Universe.

    The Molonglo telescope has a huge collecting area (18,000 square metres) and a large field of view (eight square degrees on the sky), which makes it excellent for hunting for fast radio bursts.

    Ms Caleb’s project was to develop software to sift through the 1000 TB of data produced each day. Her work paid off with the three new FRB discoveries.

    “It is very exciting to see the University of Sydney’s Molonglo telescope making such important scientific discoveries by partnering with Swinburne’s expertise in supercomputing”, says Professor Anne Green of the University of Sydney.

    Thanks to further funding from the Australian Research Council the telescope will be improved even more to gain the ability to localise bursts to an individual galaxy.

    “Figuring out where the bursts come from is the key to understanding what makes them. Only one burst has been linked to a specific galaxy,” Ms Caleb says. “We expect Molonglo will do this for many more bursts.”

    A paper on the discovery ‘The first interferometric detections of Fast Radio Bursts’ has been accepted for publication in Monthly Notices of the Royal Astronomical Society. It is available online at https://arxiv.org/abs/1703.10173

    See the full article here .

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    Swinburne U Campus

    Swinburne is a large and culturally diverse organisation. A desire to innovate and bring about positive change motivates our students and staff. The result is in an institution that grows and evolves each year.

     
  • richardmitnick 10:13 am on March 31, 2017 Permalink | Reply
    Tags: , , , , , Radio Astronomy   

    From ALMA: “Attempting the Impossible: Taking the First Picture of a Black Hole” 

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres
    ALMA

    31 March 2017
    Nicolás Lira T.
    Press 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

    The Atacama Large Millimeter/submillimeter Array (ALMA) joins for the first time the Global mm-VLBI Array (GMVA) and the Event Horizon Telescope (EHT), Earth-sized virtual observatories, which are made possible by an international collaboration of radio telescopes. One of the main drivers of this global collaboration is to study in detail the supermassive black hole at the center of our Milky Way. The GMVA will derive the properties of the accretion and outflow in the immediate surroundings of the Galactic Center, while the EHT will aim at imaging, for the very first time, the shadow of the black hole’s event horizon.

    The impressive line-up of participating telescopes stretch across the globe, from the South Pole to Europe to Hawaii, and, of course, Chile. ALMA with its 66 antennas, state-of-the-art receivers, its excellent site and southern location make it the largest and most sensitive, as well as a strategic component of both the GMVA and EHT. The observations will be done with the GMVA from April 1 to April 4, 2017, and with the EHT from April 5 to April 14, 2017.

    1
    This infographic details the locations of the participating telescopes of the Global mm-VLBI Array (GMVA), and the Event Horizon Telescope (EHT). Their goal is to image, for the very first time, the shadow of the event horizon of the supermassive black hole at the centre of the Milky Way, as well as to study the properties of the accretion and outflow around the Galactic Centre. Crédito: ESO/O. Furtak

    The outcome of these observations is eagerly awaited by the community as its scientific potential is incredibly exciting. To help understand better these forthcoming observations, ALMA and its partners have launched a blog series to explain what the GMVA and EHT projects are and the science behind them. The series will take you along an astronomical journey, providing insight into how cutting-edge research is done, describe the associated risks, and provide answers to questions such as: How do radiotelescopes see the Universe? Why are black holes so interesting? What do we know about the supermassive black hole at the center of the Milky Way?

    The first installment explains the GMVA and EHT projects in more detail and what they may see. You can read it here.

    2

    4
    ESO – ALMA and GMVA Observations in Cycle 4

    See the full article here .

    Event Horizon Telescope Array

    Event Horizon Telescope map

    The locations of the radio dishes that will be part of the Event Horizon Telescope array. Image credit: Event Horizon Telescope sites, via University of Arizona at https://www.as.arizona.edu/event-horizon-telescope.

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

    ESO/APEX
    Atacama Pathfinder EXperiment (APEX)

    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

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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.

    NRAO Small
    ESO 50 Large
    NAOJ

     
  • richardmitnick 2:11 pm on March 28, 2017 Permalink | Reply
    Tags: , , , , , Radio Astronomy,   

    From ICRAR: “Astronomers probe swirling particles in halo of starburst galaxy’ 

    ICRAR Logo
    International Centre for Radio Astronomy Research

    March 28, 2017

    1
    NGC253 starburst galaxy in optical (green; SINGG Survey) and radio (red; GLEAM) wavelengths. The H-alpha line emission, which indicates regions of active star formation, is highlighted in blue (SINGG Survey; Meurer+2006). Credits: A.D. Kapinska, G. Meurer. ICRAR/UWA/CAASTRO.

    Astronomers have used a radio telescope in outback Western Australia to see the halo of a nearby starburst galaxy in unprecedented detail.

    A starburst galaxy is a galaxy experiencing a period of intense star formation and this one, known as NGC 253 or the Sculptor Galaxy, is approximately 11.5 million light-years from Earth.

    “The Sculptor Galaxy is currently forming stars at a rate of five solar masses each year, which is a many times faster than our own Milky Way,” said lead researcher Dr Anna Kapinska, from The University of Western Australia and the International Centre for Radio Astronomy Research (ICRAR) in Perth.

    The Sculptor Galaxy has an enormous halo of gas, dust and stars, which had not been observed before at frequencies below 300 MHz. The halo originates from galactic “fountains” caused by star formation in the disk and a super-wind coming from the galaxy’s core.

    The study used data from the ‘GaLactic and Extragalactic All-sky MWA’, or ‘GLEAM’ survey, which was observed by the Murchison Widefield Array (MWA) radio telescope located in remote Western Australia.

    2
    Murchison Widefield Array (MWA) radio telescope

    “With the GLEAM survey we were able, for the first time, to see this galaxy in its full glory with unprecedented sensitivity at low radio frequencies,” said Dr Kapinska.

    “We could see radio emission from electrons accelerated by supernova explosions spiralling in magnetic fields, and absorption by dense electron-ion plasma clouds —it’s absolutely fascinating.”

    The MWA is a precursor to the Square Kilometre Array (SKA) radio telescope, part of which will be built in Western Australia in the next decade.

    Co-author Professor Lister Staveley-Smith, from ICRAR and the ARC Centre of Excellence for All-sky Astrophysics (CAASTRO), said the SKA will be the largest radio telescope in the world and will be capable of discovering many new star-forming galaxies when it comes online.

    “But before we’re ready to conduct a large-scale survey of star-forming and starburst galaxies with the SKA we need to know as much as possible about these galaxies and what triggers their extreme rate of star formation,” he said.

    PUBLICATION DETAILS

    Spectral Energy Distribution and Radio Halo of NGC 253 at Low Radio Frequencies, published in the Astrophysical Journal on March 28th, 2017.

    See the full article here .

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    ICRAR is an equal joint venture between Curtin University and The University of Western Australia with funding support from the State Government of Western Australia. The Centre’s headquarters are located at UWA, with research nodes at both UWA and the Curtin Institute for Radio Astronomy (CIRA).
    ICRAR has strong support from the government of Australia and is working closely with industry and the astronomy community, including CSIRO and the Australian Telescope National Facility, iVEC, and the international SKA Project Office (SPO), based in the UK.

    ICRAR is:

    Playing a key role in the international Square Kilometre Array (SKA) project, the world’s biggest ground-based telescope array.

    SKA Square Kilometer Array
    Attracting some of the world’s leading researchers in radio astronomy, who will also contribute to national and international scientific and technical programs for SKA and ASKAP.
    Creating a collaborative environment for scientists and engineers to engage and work with industry to produce studies, prototypes and systems linked to the overall scientific success of the SKA, MWA and ASKAP.

    SKA Murchison Widefield Array
    A Small part of the Murchison Widefield Array

    Enhancing Australia’s position in the international SKA program by contributing to the development process for the SKA in scientific, technological and operational areas.
    Promoting scientific, technical, commercial and educational opportunities through public outreach, educational material, training students and collaborative developments with national and international educational organisations.
    Establishing and maintaining a pool of emerging and top-level scientists and technologists in the disciplines related to radio astronomy through appointments and training.
    Making world-class contributions to SKA science, with emphasis on the signature science themes associated with surveys for neutral hydrogen and variable (transient) radio sources.
    Making world-class contributions to SKA capability with respect to developments in the areas of Data Intensive Science and support for the Murchison Radio-astronomy Observatory.

     
  • richardmitnick 2:59 pm on March 23, 2017 Permalink | Reply
    Tags: ALMA Observes Galaxies Embedded in Super-Halos, , , , , , Radio Astronomy   

    From ALMA: “ALMA Observes Galaxies Embedded in Super-Halos” 

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres
    ALMA

    23 March 2017
    Nicolás Lira T.
    Press 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

    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

    1
    Artist impression of a progenitor of Milky Way-like galaxy in the early Universe with a background quasar shining through a ‘super halo’ of hydrogen gas surrounding the galaxy. New ALMA observations of two such galaxies reveal that those large halos extend well beyond the galaxies’ dusty, star-forming disks. The galaxies were initially found by the absorption of background quasar light passing through the galaxies. ALMA was able to image the ionized carbon in the galaxies’ disks, revealing crucial details about their structures. Credit: A. Angelich (NRAO/AUI/NSF).

    By harnessing the extreme sensitivity of the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers have directly observed a pair of Milky Way-like galaxies seen when the Universe was only eight percent of its current age. These progenitors of today’s giant spiral galaxies are surrounded by “super halos” of hydrogen gas that extend many tens of thousands of light-years beyond their dusty, star-filled disks.

    Astronomers initially detected these galaxies by studying the intense light from even-more-distant quasars. As this light travels through an intervening galaxy on its way to Earth, it can pick up the unique spectral signature from the galaxy’s gas. This technique, however, generally prevents astronomers from seeing the actual light emitted by the galaxy, which is overwhelmed by the much brighter emission from the background quasar.

    “Imagine a tiny firefly next to a high-power searchlight. That’s what astronomers are up against when it comes to observing these young versions of our home galaxy,” said Marcel Neeleman a postdoctoral fellow at the University of California, Santa Cruz, and lead author on a paper appearing in the journal Science. “We can now see the galaxies themselves, which gives us a fantastic opportunity to learn about the earliest history of our galaxy and others like it.”

    With ALMA, the astronomers were finally able to observe the natural millimeter-wavelength “glow” emitted by ionized carbon in the dense and dusty star-forming regions of the galaxies. This carbon signature, however, is considerably offset from the gas first detected by quasar absorption. This extreme separation indicates that the galaxies’ gas content extends well beyond their star-filled disks, suggesting that each galaxy is embedded in a massive halo of hydrogen gas.

    “We had expected we would see faint emission right on top of the quasar, and instead we saw bright galaxies at large separations from the quasar,” said J. Xavier Prochaska, professor of astronomy and astrophysics at UC Santa Cruz and co-author of the paper. The separation from the quasar to the observed galaxy is about 137,000 light-years for one galaxy and about 59,000 light-years for the other.

    According to the researchers, the neutral hydrogen gas revealed by its absorption of quasar light is most likely part of a large halo or perhaps an extended disk of gas around the galaxy. “It’s not where the star formation is, and to see so much gas that far from the star-forming region means there is a large amount of neutral hydrogen around the galaxy,” Neeleman said.

    2
    Composite ALMA and optical image of a young Milky Way-like galaxy 12 billion light-years away and a background quasar 12.5 billion light-years away. Light from the quasar passed through the galaxy’s gas on its way to Earth, revealing the presence of the galaxy to astronomers. New ALMA observations of the galaxy’s ionized carbon (green) and dust continuum (blue) emission show that the dusty, star-forming disk of the galaxy is vastly offset from the gas detected by quasar absorption at optical wavelengths (red). This indicates that a massive halo of gas surrounds the galaxy. The optical data are from the Keck I Telescope at the W.M. Keck Observatory. Credit: ALMA (ESO/NAOJ/NRAO), M. Neeleman & J. Xavier Prochaska; Keck Observatory.


    Keck Observatory, Mauna Kea, Hawaii, USA

    The new ALMA data show that these young galaxies are already rotating, which is one of the hallmarks of the massive spiral galaxies we see in the Universe today. The ALMA observations further reveal that both galaxies are forming stars at moderately high rates: more than 100 solar masses per year in one galaxy and about 25 solar masses per year in the other.

    “These galaxies appear to be massive, dusty, and rapidly star-forming systems, with large, extended layers of gas,” Prochaska said.

    “ALMA has solved a decades-old question on galaxy formation,” said Chris Carilli, an astronomer with the National Radio Astronomy Observatory in Socorro, N.M., and co-author on the paper. “We now know that at least some very early galaxies have halos that are much more extended than previously considered, which may represent the future material for galaxy growth.”

    The galaxies, which are officially designated ALMA J081740.86+135138.2 and ALMA J120110.26+211756.2, are each about 12 billion light-years from Earth. The background quasars are each roughly 12.5 billion light-years from Earth.

    This research is presented in a paper titled “[C II] 158-μm emission from the host galaxies of damped Lyman alpha systems,” by M. Neeleman et al., scheduled for publication in the journal Science on 24 March 2017. [Link is above.]

    See the full article here .

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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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  • richardmitnick 11:28 am on March 22, 2017 Permalink | Reply
    Tags: , , , , Giant Magnetic Fields in the Universe, MPIFR, MPIFR/Effelsberg Radio Telescope in Germany, Radio Astronomy   

    From MPIFR: “Giant Magnetic Fields in the Universe” 


    Max Planck Institute for Radio Astronomy

    March 22, 2017

    The 100-m radio telescope Effelsberg observes magnetic structures with several million light years extent.

    Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

    The results will be published on March 22 in the journal Astronomy & Astrophysics.

    2
    The relic at the outskirts of the galaxy cluster CIZA J2242+53, named „Sausage“ because of its shape, is located at a distance of about two billion light years from us. The contour lines show the intensity of the radio emission at a wavelength of 3 cm, observed with the 100-m Effelsberg radio telescope. The colors represent the distribution of linearly polarized radio intensity at the chosen wavelength, in units of Milli-Jansky per telescope beam. The short dashes indicate the orientation of the magnetic field. The bright source at the bottom is a radio galaxy that belongs to the same galaxy cluster. Credit: © M. Kierdorf et al., A&A 600, A18

    Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the diameter of the Milky Way, they host a large number of such stellar systems, along with hot gas, magnetic fields, charged particles, embedded in large haloes of dark matter, the composition of which is unknown. Collision of galaxy clusters leads to a shock compression of the hot cluster gas and of the magnetic fields. The resulting arc-like features are called “relics” and stand out by their radio and X-ray emission. Since their discovery in 1970 with a radio telescope near Cambridge/UK, relics were found in about 70 galaxy clusters so far, but many more are likely to exist. They are messengers of huge gas flows that continuously shape the structure of the universe.

    Radio waves are excellent tracers of relics. The compression of magnetic fields orders the field lines, which also affects the emitted radio waves. More precisely, the emission becomes linearly polarized. This effect was detected in four galaxy clusters by a team of researchers at the Max Planck Institute for Radio Astronomy in Bonn (MPIfR), the Argelander Institute for Radio Astronomy at the University of Bonn (AIfA), the Thuringia State Observatory at Tautenburg (TLS), and colleagues in Cambridge/USA. They used the MPIfR’s 100-m radio telescope near Bad Münstereifel-Effelsberg in the Eifel hills at wavelengths of 3 cm and 6 cm. Such short wavelengths are advantageous because the polarized emission is not diminished when passing through the galaxy cluster and our Milky Way. Fig.1 shows the most spectacular case.

    Linearly polarized relics were found in the four galaxy clusters observed, in one case for the first time. The magnetic fields are of similar strength as in our Milky Way, while the measured degrees of polarization of up to 50% are exceptionally high, indicating that the emission originates in an extremely ordered magnetic field. “We discovered the so far largest ordered magnetic fields in the universe, extending over 5-6 million light years”, says Maja Kierdorf from MPIfR Bonn, the project leader and first author of the publication. She also wrote her Master Thesis at Bonn University on this subject. For this project, co-author Matthias Hoeft from TLS Tautenburg developed a method that permits to determine the “Mach number”, i.e. the ratio of the relative velocity between the colliding gas clouds and the local sound speed, using the observed degree of polarization. The resulting Mach numbers of about two tell us that the galaxy clusters collide with velocities of about 2000 km/s, which is faster than previously derived from measurements of the X-ray emission.

    The new Effelsberg telescope observations show that the polarization plane of the radio emission from the relics turns with wavelength. This “Faraday rotation effect”, named after the English physicist Michael Faraday, indicates that ordered magnetic fields also exist between the clusters and, together with hot gas, cause the rotation of the polarization plane. Such magnetic fields may be even larger than the clusters themselves.

    „The Effelsberg radio telescope proved again to be an ideal instrument to detect magnetic fields in the universe“, emphasizes co-author Rainer Beck from MPIfR who works on this topic for more than 40 years. “Now we can systematically search for ordered magnetic fields in galaxy clusters using polarized radio waves.”

    ——————————-

    The research team comprises of Maja Kierdorf, Rainer Beck, Matthias Hoeft, Uli Klein, Reinout van Weeren, William Forman, and Christine Jones. First author Maja Kierdorf and Rainer Beck are MPIfR employees.

    See the full article here .

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    MPIFR/Effelsberg Radio Telescope, Germany

    The Max Planck Institute for Radio Astronomy (German: Max-Planck-Institut für Radioastronomie) is located in Bonn, Germany. It is one of 80 institutes in the Max Planck Society (German: Max-Planck-Gesellschaft).

    By combining the already existing radio astronomy faculty of the University of Bonn led by Otto Hachenberg with the new Max Planck institute the Max Planck Institute for Radio Astronomy was formed. In 1972 the 100-m radio telescope in Effelsberg was opened. The institute building was enlarged in 1983 and 2002.

    The institute was founded in 1966 by the Max-Planck-Gesellschaft as the “Max-Planck-Institut für Radioastronomie” (MPIfR).

    The foundation of the institute was closely linked to plans in the German astronomical community to construct a competitive large radio telescope in (then) West Germany. In 1964, Professors Friedrich Becker, Wolfgang Priester and Otto Hachenberg of the Astronomische Institute der Universität Bonn submitted a proposal to the Stiftung Volkswagenwerk for the construction of a large fully steerable radio telescope.

    In the same year the Stiftung Volkswagenwerk approved the funding of the telescope project but with the condition that an organization should be found, which would guarantee the operations. It was clear that the operation of such a large instrument was well beyond the possibilities of a single university institute.

    Already in 1965 the Max-Planck-Gesellschaft (MPG) decided in principle to found the Max-Planck-Institut für Radioastronomie. Eventually, after a series of discussions, the institute was officially founded in 1966.

    The Max Planck Society for the Advancement of Science (German: Max-Planck-Gesellschaft zur Förderung der Wissenschaften e. V.; abbreviated MPG) is a formally independent non-governmental and non-profit association of German research institutes founded in 1911 as the Kaiser Wilhelm Society and renamed the Max Planck Society in 1948 in honor of its former president, theoretical physicist Max Planck. The society is funded by the federal and state governments of Germany as well as other sources.

    According to its primary goal, the Max Planck Society supports fundamental research in the natural, life and social sciences, the arts and humanities in its 83 (as of January 2014)[2] Max Planck Institutes. The society has a total staff of approximately 17,000 permanent employees, including 5,470 scientists, plus around 4,600 non-tenured scientists and guests. Society budget for 2015 was about €1.7 billion.

    The Max Planck Institutes focus on excellence in research. The Max Planck Society has a world-leading reputation as a science and technology research organization, with 33 Nobel Prizes awarded to their scientists, and is generally regarded as the foremost basic research organization in Europe and the world. In 2013, the Nature Publishing Index placed the Max Planck institutes fifth worldwide in terms of research published in Nature journals (after Harvard, MIT, Stanford and the US NIH). In terms of total research volume (unweighted by citations or impact), the Max Planck Society is only outranked by the Chinese Academy of Sciences, the Russian Academy of Sciences and Harvard University. The Thomson Reuters-Science Watch website placed the Max Planck Society as the second leading research organization worldwide following Harvard University, in terms of the impact of the produced research over science fields.

     
  • richardmitnick 7:55 am on March 17, 2017 Permalink | Reply
    Tags: , ALMA Confirms ability to see a “Cosmic Hole, , , , , , Radio Astronomy, Sunyaev-Zel'dovich effect (SZ effect)   

    From ALMA: “ALMA Confirms ability to see a “Cosmic Hole” 

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres
    ALMA

    17 March 2017
    Nicolás Lira T.
    Press 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

    1
    The image shows the measurement of the SZ effect in the galaxy cluster RX J1347.5-1145 taken with ALMA (blue). The background image was taken by the Hubble Space Telescope. A “hole” caused by the SZ effect is seen in the ALMA observations. Credit: ALMA (ESO/NAOJ/NRAO), Kitayama et al., NASA/ESA Hubble Space Telescope.

    Researchers using the Atacama Large Millimeter/submillimeter Array (ALMA) successfully imaged a radio “hole” around a galaxy cluster 4.8 billion light-years away from the Earth. This is the highest resolution image ever taken of such a hole caused by the Sunyaev-Zel’dovich effect (SZ effect). The image proves ALMA’s high capability to investigate the distribution and temperature of gas around galaxy clusters through the SZ effect.

    A research team led by Tetsu Kitayama, a professor at Toho University, Japan, used ALMA to investigate the hot gas in a galaxy cluster. The hot gas is an essential component to understand the nature and evolution of galaxy clusters. Even though the hot gas does not emit radio waves detectable with ALMA, the gas scatters the radio waves of the Cosmic Microwave Background and makes a “hole” around the galaxy cluster. This is the Sunyaev-Zel’dovich effect[1].

    The team observed the galaxy cluster RX J1347.5-1145 known among astronomers for its strong SZ effect and which has been observed many times with radio telescopes.

    2
    ROSAT Lensing Cluster RX J1347-1145. Max-Planck-Institut für extraterrestrische Physik

    For example, the Nobeyama 45-m Radio Telescope, operated by the National Astronomical Observatory of Japan, has revealed an uneven distribution of the hot gas in this galaxy cluster, which was not seen in X-ray observations.

    .
    Nobeyama Radio Telescope, located in the Nobeyama highlands in Nagano, Japan

    To better understand the unevenness, astronomers need higher resolution observations. But relatively smooth and widely-distributed objects, such as the hot gas in galaxy clusters, are difficult to image with high-resolution radio interferometers.

    To overcome this difficulty, ALMA utilized the Atacama Compact Array, also known as the Morita Array, the major Japanese contribution to the project.


    Atacama Compact Array alma.mtk.nao.ac.jp

    The Morita Array’s smaller diameter antennas and the close-packed antenna configuration provide a wider field of view. By using the data from the Morita Array, astronomers can precisely measure the radio waves from objects subtending a large angle on the sky.

    3
    This cluster of galaxies, RX J1347.5–1145, was observed by the NASA/ESA Hubble Space Telescope as part of the Cluster Lensing and Supernova survey with Hubble (CLASH). The cluster is one of most massive known galaxy clusters in the Universe. Credit: ESA/Hubble, NASA.


    NASA/ESA Hubble Telescope

    With ALMA, the team obtained an SZ effect image of RX J1347.5-1145, with twice the resolution and ten times better sensitivity than previous observations. This is the first image of the SZ effect with ALMA. The ALMA SZ image is consistent with the previous observations and better illustrates the pressure distribution of hot gas. It proves that ALMA is highly capable of observing the SZ effect and clearly shows that a gigantic collision is ongoing in this galaxy cluster.

    “It was nearly 50 years ago that the SZ effect was proposed for the first time,” explains Kitayama. “The effect is pretty weak, and it has been tough to image the effect with high resolution. Thanks to ALMA, this time we made a long-awaited breakthrough to pave a new path to probe the cosmic evolution.”

    Notes

    “Cosmic Microwave Background (CMB)” radio waves come from every direction. When CMB radio waves pass through the hot gas in a galaxy cluster, the radio waves interact with high-energy electrons in the hot gas and gain energy. As a result, the CMB radio waves shift to higher energy. Observing from the Earth, the CMB in the original energy range has less intensity near the galaxy cluster. This is called the “Sunyaev-Zel’dovich effect,” first proposed by Rashid Sunyaev and Yakov Zel’dovich in 1970.

    Additional information

    These observation results were published as Kitayama et al. The Sunyaev-Zel’dovich effect at 5″: RX J1347.5-1145 imaged by ALMA in the Publications of the Astronomical Society of Japan in October 2016.

    The research team members are: Tetsu Kitayama (Toho University), Shutaro Ueda (Japan Aerospace Exploration Agency), Shigehisa Takakuwa (Kagoshima University / Academia Sinica Institute of Astronomy and Astrophysics), Takahiro Tsutsumi (U. S. National Radio Astronomy Observatory), Eiichiro Komatsu (Max-Planck Institute for Astrophysics / Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo), Takuya Akahori (Kagoshima University), Daisuke Iono (National Astronomical Observatory of Japan / SOKENDAI), Takuma Izumi (The University of Tokyo), Ryohei Kawabe (National Astronomical Observatory of Japan / SOKENDAI / The University of Tokyo), Kotaro Kohno (The University of Tokyo), Hiroshi Matsuo (National Astronomical Observatory of Japan / SOKENDAI), Naomi Ota (Nara Women’s University), Yasushi Suto (The University of Tokyo), Motokazu Takizawa (Yamagata University), and Kohji Yoshikawa (University of Tsukuba).

    See the full article here .

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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.

    NRAO Small
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  • richardmitnick 1:35 pm on March 15, 2017 Permalink | Reply
    Tags: , , , , Ellie White, , , Radio Astronomy, WV Public Broadcasting   

    From GBO via WV Public Broadcasting: “W.Va. Family Fights to Save Green Bank Observatory” 

    gbo-logo

    Green Bank Radio Telescope, West Virginia, USA
    Green Bank Radio Telescope, West Virginia, USA

    gbo-sign

    Green Bank Observatory

    1

    West Virginia Public Broadcasting

    3.15.17
    Anne Li

    2
    Ellie White of Barboursville, West Virginia, and her family launched a campaign called Go Green Bank Observatory convince the National Science Foundation to not divest from Green Bank Observatory.
    Jesse Wright / West Virginia Public Broadcasting.

    Nestled in the hills in Pocahontas County, West Virginia, is the Green Bank Telescope. At 485 feet tall and about 300 feet across, it’s the largest fully-steerable telescope in the world, and it belongs to Green Bank Observatory.

    Since the observatory opened in 1957, researchers have used the facility to make several discoveries, like organic prebiotic molecules — the building blocks of life. The Green Bank Telescope is also one of only two radio telescopes in the world searching for signs of intelligent life in space.

    3
    Breakthrough Listen

    Breakthrough Listen is the largest ever scientific research program aimed at finding evidence of civilizations beyond Earth. The scope and power of the search are on an unprecedented scale:

    The program includes a survey of the 1,000,000 closest stars to Earth. It scans the center of our galaxy and the entire galactic plane. Beyond the Milky Way, it listens for messages from the 100 closest galaxies to ours.

    The instruments used are among the world’s most powerful. They are 50 times more sensitive than existing telescopes dedicated to the search for intelligence.

    The radio surveys cover 10 times more of the sky than previous programs. They also cover at least 5 times more of the radio spectrum – and do it 100 times faster. They are sensitive enough to hear a common aircraft radar transmitting to us from any of the 1000 nearest stars.

    The GBT plays a key role in the Breakthough Listen project, and roughly 20% of the time available on the GBT is dedicated to this research.

    Breakthrough Listen is also carrying out the deepest and broadest ever search for optical laser transmissions. These spectroscopic searches are 1000 times more effective at finding laser signals than ordinary visible light surveys. They could detect a 100 watt laser (the energy of a normal household bulb) from 25 trillion miles away.

    Listen combines these instruments with innovative software and data analysis techniques.

    The initiative will span 10 years and commit a total of $100,000,000.

    More information on Breakthrough Listen is available at https://breakthroughinitiatives.org/Initiative/1

    But today, the telescope and the facility that supports it are under federal review — with the possibility of losing funding or being dismantled.

    In the face of that threat, one West Virginia family hopes to convince the powers that be of the facility’s value to science, education and the small town in which the telescope resides.

    “It’s almost like a tiny metropolitan city in the middle of rural West Virginia,” said Ellie White, a 16-year-old from Barboursville, West Virginia. “That kind of resource is invaluable for kids across the state and across the country, who are going to be tomorrow’s innovators, engineers, scientists, politicians, artists.”

    White’s family volunteered to start a campaign called Go Green Bank Observatory to rally support from across the country and show the National Science Foundation, which used to almost completely fund the observatory, that Green Bank Observatory is worth keeping. In 2012, the NSF published a portfolio review that recommended at least partially divesting from several observatories around the country that no longer have as large of a scientific impact as they used to. Green Bank Observatory was on that list.

    Proposed operational changes for Green Bank Observatory range from continuing to partially fund its operations to shutting down its research operations and turning it into a technology park, or completely tearing it down.

    “This is one of the difficult things the NSF has to do,” said Edward Ahjar, an astronomer at the NSF. “All of our facilities do great science, and that’s why we fund them. But when we start having less and less money to spread around, then we have to prioritize them. Which are doing the most important science now? Which are lower ranked?”

    The Fight to Keep Green Bank Observatory Open

    Last fall, Go Green Bank Observatory encouraged fans to speak at two public scoping meetings where Ahjar and other representatives from the NSF would be present to hear the public’s input about the divestment process.

    About 350 people filled the seats of an auditorium at the observatory. Several in attendance were affiliated with West Virginia University, which since 2006 has received more than $14.5 million in grant dollars for research related to the Green Bank Telescope.

    “When I started applying for graduate school, WVU was one of my top choices,” said Kaustubh Rajwade, a graduate student from India in the Department of Physics and Astronomy at WVU. “The only reason I came here was so I could use the Green Bank Telescope.”

    Others, like Buster Varner, a local fire chief, were more concerned about Green Bank Observatory’s role in the community as a de facto community center, where people can hold meetings and classes.

    “Whenever we had a catastrophe, we can go to Mike,” Varner said, referring to Mike Holstine, the business manager at Green Bank Observatory. “I don’t know much about this science, and there’s a lot of people here who does and that’s great. But I do not want anything to happen to this facility, period.”

    The NSF once almost completely funded Green Bank Observatory’s operations. But Holstine said that especially in the past five years, the observatory saw a need to diversify its sources of funding — in part because outside organizations and researchers expressed a willingness to pay for time on the telescope, but also due to the clear indicators that the observatory needed to rely less on the NSF.

    Green Bank Observatory employs between 100 and 140 people — more than half of whom are from Pocahontas County — depending on the time of year. The money also helps the observatory maintain its own infrastructure in an isolated and rural area.

    “You kind of need to think of us as a town, a self-contained town,” Holstine explained. “We have our own roads. We have our own water system. We have our own wastewater system. We take care of our own buildings. We mow our own grass; we cut our own trees. We have to plow snow in the winter.”

    A Future Without Green Bank Observatory

    For White, the Observatory isn’t only worth keeping because of its accomplishments — but also because of its efforts to train the next generation of scientists. When she was younger, White was convinced she wanted to be an artist when she grew up. But since playing among the telescopes as a child, she has gone on to work on projects under the mentorship of astronomers and graduate students from all over the world.

    She’s not the only teen who’s been impacted by the observatory’s work; through the Pulsar Search Collaboratory, more than 2,000 high school students have worked with the Green Bank Observatory through a partnership with West Virginia University since 2007.

    “Just generally being here, you learn something every day. It’s like learning a new language through immersion,” White said.

    The NSF will reach its decision about the Green Bank Observatory’s fate by the end of this year or the beginning of next year. At 16 years old, White hopes to get her doctorate in astrophysics and one day find full employment at the observatory. If it shuts down, White said, she might have to look for employment out of state.

    See the full article here .

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    Mission Statement

    Green Bank Observatory enables leading edge research at radio wavelengths by offering telescope, facility and advanced instrumentation access to the astronomy community as well as to other basic and applied research communities. With radio astronomy as its foundation, the Green Bank Observatory is a world leader in advancing research, innovation, and education.

    History

    60 years ago, the trailblazers of American radio astronomy declared this facility their home, establishing the first ever National Radio Astronomy Observatory within the United States and the first ever national laboratory dedicated to open access science. Today their legacy is alive and well.

     
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