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  • richardmitnick 1:32 pm on February 23, 2018 Permalink | Reply
    Tags: , , , , , , , Radio Astronomy   

    From ALMA: “Large Magellanic Cloud Contains Surprisingly Complex Organic Molecules” 

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

    ALMA

    30 January, 2018

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

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

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    Richard Hook
    Public Information Officer, ESO
    Garching bei München, Germany
    Phone: +49 89 3200 6655
    Cell phone: +49 151 1537 3591
    Email: rhook@eso.org

    1
    Astronomers using ALMA have uncovered chemical “fingerprints” of methanol, dimethyl ether, and methyl formate in the Large Magellanic Cloud. The latter two molecules are the largest organic molecules ever conclusively detected outside the Milky Way. The far-infrared image on the left shows the full galaxy. The zoom-in image shows the star-forming region observed by ALMA. It is a combination of mid-infrared data from Spitzer and visible (H-alpha) data from the Blanco 4-meter telescope. Credit: NRAO/AUI/NSF; ALMA (ESO/NAOJ/NRAO); Herschel/ESA; NASA/JPL-Caltech; NOAO

    NASA/Spitzer Infrared Telescope

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

    ESA/Herschel spacecraft

    The nearby dwarf galaxy known as the Large Magellanic Cloud (LMC) is a chemically primitive place.

    Large Magellanic Cloud. Adrian Pingstone December 2003

    Unlike the Milky Way, this semi-spiral collection of a few tens-of-billions of stars lacks our galaxy’s rich abundance of heavy elements, like carbon, oxygen, and nitrogen. With such a dearth of heavy elements, astronomers predict that the LMC should contain comparatively paltry amounts of complex carbon-based molecules. Previous observations of the LMC seem to support that view.

    New observations with the Atacama Large Millimeter/submillimeter Array (ALMA), however, have uncovered the surprisingly clear chemical “fingerprints” of the complex organic molecules methanol, dimethyl ether, and methyl formate. Though previous observations found hints of methanol in the LMC, the latter two are unprecedented findings and stand as the most complex molecules ever conclusively detected outside of our galaxy.

    Astronomers discovered the molecules’ faint millimeter-wavelength “glow” emanating from two dense star-forming embryos in the LMC, regions known as “hot cores.” These observations may provide insights into the formation of similarly complex organic molecules early in the history of the universe.

    “Even though the Large Magellanic Cloud is one of our nearest galactic companions, we expect it should share some uncanny chemical similarity with distant, young galaxies from the early universe,” said Marta Sewiło, an astronomer with NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and lead author on a paper appearing in the Astrophysical Journal Letters.

    Astronomers refer to this lack of heavy elements as “low metallicity.” It takes several generations of star birth and star death to liberally seed a galaxy with heavy elements, which then get taken up in the next generation of stars and become the building blocks of new planets.

    “Young, primordial galaxies simply didn’t have enough time to become so chemically enriched,” said Sewiło. “Dwarf galaxies like the LMC probably retained this same youthful makeup because of their relatively low masses, which severely throttles back the pace of star formation.”

    “Due to its low metallicity, the LMC offers a window into these early, adolescent galaxies,” noted Remy Indebetouw, an astronomer at the National Radio Astronomy Observatory in Charlottesville, Virginia, and coauthor on the study. “Star-formation studies of this galaxy provide a stepping stone to understand star formation in the early universe.”

    The astronomers focused their study on the N113 Star Formation Region in the LMC, which is one of the galaxy’s most massive and gas-rich regions. Earlier observations of this area with NASA’s Spitzer Space Telescope and ESA’s Herschel Space Observatory revealed a startling concentration of young stellar objects – protostars that have just begun to heat their stellar nurseries, causing them to glow brightly in infrared light. At least a portion of this star formation is due to a domino-like effect, where the formation of massive stars triggers the formation of other stars in the same general vicinity.

    Sewiło and her colleagues used ALMA to study several young stellar objects in this region to better understand their chemistry and dynamics. The ALMA data surprisingly revealed the telltale spectral signatures of dimethyl ether and methyl formate, molecules that have never been detected so far from Earth.

    Complex organic molecules, those with six or more atoms including carbon, are some of the basic building blocks of molecules that are essential to life on Earth and – presumably – elsewhere in the universe. Though methanol is a relatively simple compound compared to other organic molecules, it nonetheless is essential to the formation of more complex organic molecules, like those that ALMA recently observed, among others.

    If these complex molecules can readily form around protostars, it’s likely that they would endure and become part of the protoplanetary disks of young star systems. Such molecules were likely delivered to the primitive Earth by comets and meteorites, helping to jumpstart the development of life on our planet.

    The astronomers speculate that since complex organic molecules can form in chemically primitive environments like the LMC, it’s possible that the chemical framework for life could have emerged relatively early in the history of the universe.
    Additional Information

    This research is presented in a paper titled “’The detection of hot cores and complex organic molecules in the Large Magellanic Cloud,” by M. Sewiło, et al., which appears in The Astrophysical Journal Letters.

    The research team was composed by Marta Sewilo [1], Remy Indebetouw [2, 3], Steven B. Charnley [1], Sarolta Zahorecz [4, 5], Joana M. Oliveira [6], Jacco Th. van Loon [6], Jacob L. Ward [7], C.-H. Rosie Chen [8], Jennifer Wiseman [1], Yasuo Fukui [9], Akiko Kawamura [10], Margaret Meixner [11], Toshikazu Onishi [4], and Peter Schilke [12].

    [1] NASA Postdoctoral Program Fellow, NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771, USA
    [2] Department of Astronomy, University of Virginia, PO Box 400325, Charlottesville, VA 22904, USA
    [3] National Radio Astronomy Observatory, 520 Edgemont Rd, Charlottesville, VA 22903, USA
    [4] Department of Physical Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, 599-8531, Japan
    [5] Chile Observatory, National Astronomical Observatory of Japan, National Institutes of Natural Science, 2-21-1 Osawa, Mitaka, Tokyo, 181-8588, Japan
    [6] Lennard-Jones Laboratories, Keele University, ST5 5BG, UK
    [7] Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg Germany
    [8] Max-Planck-Institut für Radioastronomie, Auf dem Hügel, 69 D-53121 Bonn, Germany
    [9] School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
    [10] National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan
    [11] Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
    [12] I. Physikalisches Institut der Universität zu Köln, Zülpicher Str. 77, 50937, Köln, Germany

    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

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  • richardmitnick 9:22 am on February 23, 2018 Permalink | Reply
    Tags: Aecibo, , , , , Radio Astronomy,   

    From Science: “Iconic Arecibo radio telescope saved by university consortium” 

    AAAS
    Science Magazine

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    The Arecibo radio telescope will soon be managed by a university consortium. GDA/AP Images

    Feb. 22, 2018
    Daniel Clery
    Adrian Cho

    A consortium led by the University of Central Florida (UCF) in Orlando will take over management of the Arecibo Observatory in Puerto Rico, home to one of the world’s largest radio telescope, the National Science Foundation (NSF) in Alexandria, Virginia, announced today. NSF has been looking for another body to take over the running of the iconic facility ever since a 2006 review suggested the agency ramp down its funding to free up money for newer projects.

    “We’re delighted that there are signatures on paper,” says Richard Green, director of NSF’s astronomical sciences division. “That’s a fabulous moment at the end of a long process.” NSF now spends $8 million a year to run Arecibo, with NASA pitching in another $3.6 million. Under the agreement signed today, by 1 October 2022, NSF’s contribution will shrink to $2 million per year, with the UCF consortium making up the difference. UCF will complete the takeover as operator on 1 April, although an agreement detailing the transfer of funds must still be finalized, says James Ulvestad, NSF’s chief officer for scientific facilities.

    UCF has teamed up with the Metropolitan University in San Juan and Yang Enterprises in Oviedo, Florida, a company that has NASA and U.S. Air Force contracts to operate and maintain facilities. Ray Lugo, head of UCF’s Florida Space Institute, says the consortium hopes to bring in new users to contribute toward costs. He says the U.S. Department of Defense may want to use Arecibo to test sensors, while space mining companies may want to scope out target asteroids. “We want to bring other customers to the table,” he says. The consortium also wants to expand the telescope’s scientific capabilities, in part by upgrading equipment as repairs are carried out in the wake of damage suffered during following Hurricane Maria.

    Users of the 305-meter radio dish include astronomers, planetary scientists, and atmospheric physicists, and Arecibo is still a powerful scientific tool for them, even at 54 years old. The agreement with UCF also recognizes Arecibo’s significance beyond the scientific community, Ulvestad says. “It’s a hugely important technological icon in an underserved community,” he says.

    Some scientists are relieved that the facility avoided closure, even though they lament the handover from NSF. “I am pleased by the commitment of new management to continue and to expand the scientific and educational excellence of Arecibo Observatory,” says Robert Kerr, former Arecibo director. “I am disappointed by the tragic and ill-conceived divestment by NSF. That is a net loss for the foundation, and for basic U.S. scientific research and development.”

    NSF views the agreement with UCF as a possible blueprint for efforts to finding alternative funding for other aging telescopes, Green says. In particular, in 2012 a review committee recommended that the agency ramp down its funding for the 100-meter Green Bank Telescope in West Virginia.

    GBO radio telescope, Green Bank, West Virginia, USA

    “We’re hoping that [the Arecibo agreement] will give us and the community confidence that as other divestment efforts proceed, we can reach similar outcomes,” Green says.

    See the full article here .

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  • richardmitnick 12:43 pm on February 22, 2018 Permalink | Reply
    Tags: , , , Cornwall to host world’s first commercial deep-space communications station, , GOONHILLY SATELLITE EARTH STATION, Radio Astronomy   

    From UK Space: “Cornwall to host world’s first commercial deep-space communications station” 

    UK Space Agency

    UK Space Agency

    22 February 2018
    Sam Gyimah MP

    An £8.4 million investment in Goonhilly Earth Station, in Cornwall, will help create the world’s first commercial deep-space communications station, capable of tracking future missions to the Moon and Mars.

    1
    GOONHILLY SATELLITE EARTH STATION

    Under a new project Goonhilly, which famously beamed images of the moon landings to millions of television viewers, will be upgraded to enable it to provide deep-space tracking and satellite communication services on a commercial basis. It will be the first time the UK has had the capability to communicate directly with deep-space missions.

    Science Minister Sam Gyimah said:

    “We’re working hard to ensure the UK thrives in the commercial space age as part of the Government’s Industrial Strategy, so it’s fantastic to see the world’s first commercial deep space communications network coming to Cornwall.

    “The UK Space Agency has played a vital role in supporting this partnership and will continue to work alongside industry, local leaders and international partners to grow the UK’s share of the global space market. We already play a significant role in satellite manufacturing, with one in four of the world’s telecommunications satellites built in the UK, and want to establish the UK as a world-leading destination for space launch. ”

    In future, Goonhilly will complement the capability of the European Space Agency (ESA)’s worldwide ground station network, which today comprises seven core stations supporting more than 20 earth, observatory, planetary and exploration spacecraft as well as European launchers.

    The contract is being funded through the Cornwall and Isles of Scilly LEP’s Growth Deal with the UK Government, via ESA, including €2 million which comes from the UK Space Agency’s investment in ESA. The investment will see ESA working with Goonhilly to upgrade one of its largest antennas, the 32 m-diameter GHY-6 antenna built in 1985, to meet the high-end performance and technology requirements needed by ESA, NASA and private space exploration companies for deep-space communications, including high bit-rate data links.

    Colin Baldwin, Head of Local Growth Strategy at the UK Space Agency, said:

    “We are delighted that the work the Agency did to support this partnership has come to fruition. We see huge opportunities for the developing space sector in Cornwall and look forward to working with local partners, including Goonhilly Earth Station and the LEP, as their plans develop.”

    The investment will provide a huge boost to Cornwall’s space ambitions. Once the upgrade work is complete, Goonhilly will have the ability to track and control forthcoming robotic and human missions to the Moon and Mars, making a significant technical and economic contribution to European efforts in global space exploration.

    During the approximately two-year work to upgrade the 32 m-diameter GHY-6 antenna – which carried the 1985 Live Aid concert around the world shortly after it was built – qualifying tests will be carried out under ESA’s oversight to include tracking of several of the Agency’s deep-space missions, including the Mars Express spacecraft which has been in orbit around the Red Planet since 2003.

    Goonhilly CEO Ian Jones said: “We already have a great deal of interest in using the upgraded antenna from our international customer base. This includes space agencies, such as ESA, as well as some of the new private space exploration companies.

    “The team here at Goonhilly, along with colleagues at the LEP, ESA and the UK Space Agency, have been working incredibly hard to achieve this fantastic outcome. We now look forward to getting on with the upgrade work which will bring a new expansion of the company.”

    The UK’s Local Growth Minister, Jake Berry, said:

    “It is very encouraging to see a Local Enterprise Partnership using Government’s Growth Deal funding to support a rapidly growing sector through public and private sector collaboration. This contract will create skilled new jobs in the local area while assuring Cornwall’s place in history for its contribution to space exploration.”

    [Strange, no mention of the NASA Deep Space Network.]

    See the full article here .

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    The UK Space Agency is responsible for all strategic decisions on the UK civil space programme and provides a clear, single voice for UK space ambitions.

    At the heart of UK efforts to explore and benefit from space, we are responsible for ensuring that the UK retains and grows a strategic capability in space-based systems, technologies, science and applications. We lead the UK’s civil space programme in order to win sustainable economic growth, secure new scientific knowledge and provide benefit to all citizens.

    We work to:

    co-ordinate UK civil space activity
    encourage academic research
    support the UK space industry
    raise the profile of UK space activities at home and abroad
    increase understanding of space science and its practical benefits
    inspire our next generation of UK scientists and engineers
    licence the launch and operation of UK spacecraft
    promote co-operation and participation in the European Space programme

    We’re an executive agency of the Department for Business, Innovation and Skills, made up of about 70 staff based in Swindon, London and the UK Space Gateway in Oxfordshire.

    We are responsible for:

    leading the UK civil space policy and increasing the UK contribution to European initiatives
    building a strong national space capability, including scientific and industrial centres of excellence
    co-ordinating strategic investment across industry and academia
    working to inspire and train a growing, skilled UK workforce of space technologists and scientists
    working on national and international space projects in co-operation with industry and academia
    regulating the UK civil space activities and ensuring we meet international treaty obligations

     
  • richardmitnick 10:34 am on February 22, 2018 Permalink | Reply
    Tags: , , , , , Radio Astronomy   

    From AARNet: “Why AARNet’s intercontinental cable partnership leads the way for R+E networks globally” 

    aarnet-bloc

    AARNet

    1

    Alexander van den Hil, is the Dutch national research and education network, SURFnet‘s product manager for national and international network services. Here he posts about AARNet’s innovative role as a partner (with Google, Indosat Ooredoo, Singtel, SubPartners, and Telstra) in the Indigo Project consortium to build additional connectivity between Australia and South East Asia, and why SURFnet wants to replicate this model for trans-Atlantic connectivity.

    AARNet has secured a scoop: they are the first NREN (national research and education network) partner in a consortium for laying a submarine cable under the Indian Ocean for network connections. What is so special about that, and in particular, why does SURFnet also want this in the future? Because it means you have complete control of your own cable.

    Determining and sharing capacity

    SURFnet is aware of the importance of having complete control of the cables in your network. On our fibre optic network in the Netherlands, we can determine precisely how we light the fibres. This means that we can determine the capacity of the fibres because we select the equipment that modulates the light (the better and more modern the equipment, the greater the capacity that you can send over a beam of light). This self-determination also makes it possible to share the capacity of the fibres with other parties. And it provides space for innovation: what if we also wish to offer 400 Gbit/s connections, or ultimately even 1 Tbit/s? Then we can develop that.

    Cross border fibres

    In the Netherlands, we have our own network and we are therefore in a position to do these things. In addition, we have (together with other NRENs) a number of connections with cities in Europe, including Hamburg, Geneva, Paris and London. These are called cross border fibres (CBFs). We can do exactly what we wish with these connections as well. For example, we make part of the spectrum available to the European research network GÉANT, which partly relies on our CBFs for its network.

    1

    Limitations of leasing

    SURFnet also has a number of trans-Atlantic connections, the ANA-300, again together with a number of other NRENs. However, we purchase these connections from a consortium of telecom providers. They control the cables and lease part of the capacity, in this case 100 Gbit/s, to SURFnet and partners. We are thus locked into this 100 Gbit/s, at layer 2. That provides relatively little flexibility: we are tied to the technical options (and limitations) provided by the leasing telecom operators.

    Dream: control of our trans-Atlantic connections

    How wonderful it would be if we also had complete control of our trans-Atlantic connections. We would then be in a position to develop links with our American and Canadian colleagues at Internet2 and CANARIE that we could adapt fully to our own wishes and requirements. It is with some jealousy that we look towards our colleagues at AARNet, the Australian research network. They have actually achieved a great thing which remains unique.

    AARNet realises Project Indigo

    AARNet is actually part of a consortium that is laying a trans-Atlantic submarine cable connection between Perth and Indonesia/Singapore: Project Indigo.

    6
    Project Indigo

    Large companies such as Telstra, Indosat and Google are represented in that consortium. AARNet is also involved. In future (from 2019, when the cable is in place) AARNet will cease purchasing Ethernet service from one of the telecom operators, and will instead manage its part of the cable connection independently. It will thus be in a position to specify what type of equipment it uses on the fibres, for example. Among other things, this independence is of great importance for the telescope being built in Perth as part of the SKA (Square Kilometre Array) project. In this project, telescopes in Australia and South Africa make observations, the (big) data of which will be available throughout the world.

    Special achievement

    It is the first time that an NREN has formed part of such a consortium, and that is a special achievement. It doesn’t just happen by chance. Laying such a submarine cable connection is a huge project: it takes a lot of time and naturally involves a considerable investment. At SURFnet we are of course following this development with interest. We are proud of the achievement of our Australian colleagues, and we are in discussions with European partners in order to see whether we could also be part of such a large intercontinental project in the future.

    See the full article here .

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    AARNet provides critical infrastructure for driving innovation in today’s knowledge-based economy

    Australia’s Academic and Research Network (AARNet) is a national resource – a National Research and Education Network (NREN). AARNet provides unique information communications technology capabilities to enable Australian education and research institutions to collaborate with each other and their international peer communities.

     
  • richardmitnick 10:11 am on February 22, 2018 Permalink | Reply
    Tags: , , , , , New technology to synchronise radio telescopes, Radio Astronomy   

    From AARNet: “AARNet supports new technology to synchronise radio telescopes” 

    aarnet-bloc

    AARNet

    February 6, 2018

    1
    Image credit: Radio telescopes, D Smyth CSIRO

    Australian researchers have used the AARNet network to synchronize two radio telescopes 100 kilometres apart, replacing the need for atomic clocks.

    A consortium of researchers demonstrated for the first time that a stable frequency reference — used to calibrate clocks and instruments — could be reliably transmitted more than 300 kilometres on AARNet optical fibre.

    The new technology could be particularly useful for the Square Kilometre Array, a global effort to detect faint radio waves from deep space with a sensitivity about 50 times greater than that of the Hubble telescope.

    Linking radio telescopes in an array requires that each telescope have access to an atomic clock to record the precise time at which a signal is detected from an object in space.

    Stable transmitted references could be used to calibrate the relative time at each telescope, eliminating the need for multiple atomic clocks in a radio telescope array.

    “This highly stable method for transmitting the frequency reference allows an atomic clock, which cost around two hundred thousand dollars, to be replaced with a system that only costs a few tens of thousand dollars,” said Kenneth Baldwin, a member of the research team from the Australian National University.

    In the results published in Optica , the Optical Society journal, the researchers show that the technique is capable of compensating for signal fluctuations in the fiber optic network introduced by environmental factors such as temperature changes or vibrations.

    The AARNet optical fibres were even carrying live traffic at the same time as the demonstration was performed.

    “By running the experiment on optical fibers also carrying normal traffic, we showed that transmitting the stable frequency standard doesn’t affect the data or telephone calls on the other channels,” said Baldwin.

    AARNet’s Tim Rayner, Optical Engineer, explains that AARNet’s dark fibre footprint already extended from the laboratories to the two telescope sites: the Australia Telescope Compact Array (ATCA) in north-west NSW and the Mopra radio telescope.

    CSIRO ATCA at the Paul Wild Observatory, about 25 km west of the town of Narrabri in rural NSW about 500 km north-west of Sydney, AU

    ATNF Mopra 22 meter radio telescope, situated near the Warrumbungle National Park, just outside the town of Coonabarabran in New South Wales, Australia

    “We were keen to use our dark fibre infrastructure to support the research efforts of our community by running experimental services as well as contributing our expertise and operational capability.”

    The AARNet team helped design the solution for the timing signals to use a particular optical wavelength, and installed optical amplifiers for the project in intermediate points co-located with other AARNet production equipment.

    “Sending precise timing signals over optical fibre networks is essential to radio astronomy projects like the SKA,” said Tim.

    SKA Square Kilometer Array

    “This work is an important example of AARNet’s support for research in the fibre optic and astronomy fields, which continues through our participation in the SKA project.”

    The consortium of researchers are from AARNet, the Australian National University, CSIRO, the National Measurement Institute, Macquarie University and the University of Adelaide.

    See the full article here .

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    AARNet provides critical infrastructure for driving innovation in today’s knowledge-based economy

    Australia’s Academic and Research Network (AARNet) is a national resource – a National Research and Education Network (NREN). AARNet provides unique information communications technology capabilities to enable Australian education and research institutions to collaborate with each other and their international peer communities.

     
  • richardmitnick 2:19 pm on February 20, 2018 Permalink | Reply
    Tags: , , , , , , , Radio Astronomy   

    From ALMA: “Chaotic Turbulence Roiling ‘Most Luminous Galaxy’ in the Universe” 2016 

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

    ALMA

    15 January, 2016 [Just found this.]

    Contacts

    Tanio Díaz Santos
    Núcleo de Astronomía, Facultad de Ingeniería
    Universidad Diego Portales, Santiago, Chile
    Tel: +56 2 2213 0480
    Email: tanio.diaz@mail.udp.cl

    Valeria Foncea

    Education and Public Outreach Officer

    Joint ALMA Observatory

    Santiago, Chile

    Tel: +56 2 467 6258

    Cell: +56 9 75871963
    Email: vfoncea@alma.cl

    Charles E. Blue
    Public Information Officer
    National Radio Astronomy Observatory
    Charlottesville, Virginia, USA
    Tel: +1 434 296 0314
    Cell: +1 434.242.9559
    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 impression of W2246-0526, a single galaxy glowing in infrared light as intensely as approximately 350 trillion suns. It is so violently turbulent that it may eventually jettison its entire supply of star-forming gas, according to new observations with ALMA. Credit: NRAO/AUI/NSF; Dana Berry / SkyWorks; ALMA (ESO/NAOJ/NRAO).

    The most luminous galaxy in the Universe –a so-called obscured quasar 12.4 billion light-years away – is so violently turbulent that it may eventually jettison its entire supply of star-forming gas, according to new observations with the Atacama Large Millimeter/submillimeter Array (ALMA).

    A team of researchers used ALMA to trace, for the first time, the actual motion of the galaxy’s interstellar medium – the gas and dust between the stars. What they found, according to Tanio Díaz-Santos of the Universidad Diego Portales in Santiago, Chile, and lead author of this study, is a galaxy “so chaotic that it is ripping itself apart.”

    Previous studies with NASA’s Wide-field Infrared Survey Explorer (WISE) spacecraft reveal that the galaxy, dubbed W2246-0526, is glowing in infrared light as intensely as approximately 350 trillion suns.

    NASA/WISE Telescope

    Evidence strongly suggests that this galaxy is actually an obscured quasar, a very distant galaxy which contains a voraciously feeding supermassive black hole at its center that is completely obscured behind a thick blanket of dust.

    This galaxy’s startling brightness is powered by a tiny, yet incredibly energetic disk of gas that is being superheated as it spirals in on the supermassive black hole. The light from this blazingly bright accretion disk is then absorbed by the surrounding dust, which re-emits the energy as infrared light.

    “These properties make this object a beast in the infrared,” said Roberto Assef, an astronomer with the Universidad Diego Portales and leader of the ALMA observing team. “The powerful infrared energy emitted by the dust then has a direct and violent impact on the entire galaxy, producing extreme turbulence throughout the interstellar medium.”

    The astronomers compare this turbulent action to a pot of boiling water. If these conditions continue, they say, the galaxy’s intense infrared radiation would boil away all of its interstellar gas.

    This galaxy belongs to a very unusual type of quasar known as Hot, Dust-Obscured Galaxies or Hot DOGs. These objects are very rare; only 1 out of every 3,000 quasars observed by WISE belong to this class.

    The research team used ALMA to precisely map the motion of ionized carbon atoms throughout the entire galaxy. These atoms, which are tracers for interstellar gas, naturally emit infrared light, which becomes shifted to millimeter wavelengths as it travels the vast cosmic distances to Earth due to the expansion of the Universe.

    “Large amounts of ionized carbon were found in an extremely turbulent dynamic state throughout the galaxy,” Díaz-Santos describes. The data reveal that this interstellar material is careening anywhere from 500 to 600 kilometers per second across the entire galaxy.

    The astronomers believe that this turbulence is primarily due to the fact that the region around the black hole is at least 100 times more luminous than the rest of the host galaxy combined; in other quasars, the proportion is much more modest. This intense yet localized radiation exerts tremendous pressure on the entire galaxy, to potentially devastating effect.

    “We suspected that this galaxy was in a transformative stage of its life because of the enormous amount of infrared energy discovered with WISE,” said Peter Eisenhardt with NASA’s Jet Propulsion Laboratory in Pasadena, California, and scientific leader of the WISE mission. “Now ALMA has shown us that the raging furnace in this galaxy is making the pot boil over.”

    Current models of galactic dynamics combined with the ALMA data indicate that this galaxy is unstable and its interstellar gas is being blown away in all directions. This means that the galaxy’s Hot DOG days are numbered as it matures into a more traditional unobscured quasar.

    “If this pattern continues, it is possible that in the future W2246 ends up shedding a large part of the gas and dust it contains,” concludes Manuel Aravena also from the Universidad Diego Portales, and co-author of the study. “Only ALMA, with its unparalleled resolution, can allow us to see this object in high definition and fathom such an important episode in the life of this galaxy.”

    This article, The Strikingly Uniform, Highly Turbulent Interstellar Medium of The Most Luminous Galaxy in the Universe, will be published in The Astrophysical Journal Letters.

    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 2:00 pm on February 20, 2018 Permalink | Reply
    Tags: , ALMA Deepen Mystery about the relation between Supermassive Black Holes and their Host Galaxies, , , , , , Radio Astronomy   

    From ALMA: “ALMA Deepen Mystery about the relation between Supermassive Black Holes and their Host Galaxies” 

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

    ALMA

    20 February, 2018

    Nicolás Lira

    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    Richard Hook
    Public Information Officer, ESO
    Garching bei München, Germany
    Phone: +49 89 3200 6655
    Cell phone: +49 151 1537 3591
    Email: rhook@eso.org

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

    1
    Figure 3: A schematic view of the fact that an ionized gas outflow (green) driven by the central supermassive black hole does not affect the star formation of its host galaxy. This situation may occur if the ionized gas is outflowing perpendicularly to the molecular gas. Credit: ALMA (ESO/NAOJ/NRAO).

    Using the Atacama Large Millimeter/submillimeter Array (ALMA) to observe an active galaxy with a strong ionized gas outflow from the galactic center, astronomers have obtained a result making astronomers even more puzzled: an unambiguous detection of carbon monoxide (CO) gas associated with the galactic disk. However, they have also found that the CO gas which settles in the galaxy is not affected by the strong ionized gas outflow launched from the galactic center.

    According to a popular scenario explaining the formation and evolution of galaxies and supermassive black holes, radiation from galactic centers, where supermassive black holes are, can significantly influence the molecular gas (such as CO) and the star formation activities of the galaxies.

    ALMA result shows that the ionized gas outflow driven by the supermassive black hole does not necessarily affect its host galaxy. This result “has made the co-evolution of galaxies and supermassive black holes more puzzling,” explains Dr. Yoshiki Toba from the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA, Taiwan), and main author of this research. “The next step is looking into more data of this kind of galaxies. That is crucial for understanding the full picture of the formation and evolution of galaxies and supermassive black holes”.

    Answering the question “How did galaxies form and evolve during the 13.8-billion-year history of the universe?” has been one top issue in modern astronomy. Studies already revealed that almost all massive galaxies harbor a supermassive black hole at their centers. In recent findings, studies further showed the tight correlation between the mass of black holes and those of their host galaxies. This correlation suggests that supermassive black holes and their host galaxies have evolved together and they closely interacted each other as they grew, as known as the co-evolution of galaxies and supermassive black holes.

    The gas outflow driven by a supermassive black hole at the galactic center recently has become the focus of attention as it possibly is playing a key role in the co-evolution of galaxies and black holes. A widely accepted idea has described this phenomenon as the intense radiation from the galactic center in which is the supermassive black hole ionizes [1] the surrounding gas, even affecting the molecular gas that is the ingredient of star formation. The strong radiation activates [2] or suppresses [3] the star formation of galaxies. However, “we astronomers do not understand the real relation between the activity of supermassive black holes and star formation in galaxies,” says Tohru Nagao, Professor at Ehime University. “Therefore, many astronomers including us are eager to observe the real scene of the interaction between the nuclear outflow and the star-forming activities, for revealing the mystery of the co-evolution.”

    1
    Figure 1: Image of a DOG, WISE1029. The left and right panels show an optical image from the Sloan Digital Sky Survey (SDSS), and mid-infrared image from WISE, respectively. The image size is 30 square arcsecond (1 arcsecond is 1/3600 degree). It is clear that DOGs are faint in the optical, but are incredibly bright in the infrared. The SDSS spectrum indicates that strong ionized gas is outflowing toward us from WISE1029. Credit: Sloan Digital Sky Survey/NASA/JPL-Caltech

    SDSS Telescope at Apache Point Observatory, near Sunspot NM, USA, Altitude 2,788 meters (9,147 ft)

    NASA/WISE Telescope

    Astronomers believe that DOGs harbor actively growing supermassive black holes in their nuclei [4]. In particular, one DOG (WISE1029+0501, hereafter WISE1029) is outflowing gas ionized by the intense radiation from its supermassive black hole. WISE1029 is known as an extreme case concerning ionized gas outflow, and this particular factor has motivated the researchers to see what happens to its molecular gas.

    By making use of ALMA’s outstanding sensitivity which is excellent in investigating properties of molecular gas and star-forming activities in galaxies, the team conducted their research by observing the CO and the cold dust of galaxy WISE1029 (Figure 2). After detailed analysis, surprisingly they found, there is no sign of significant molecular gas outflow. Furthermore, star-forming activity is neither activated nor suppressed. This indicates that a strong ionized gas outflow launched from the supermassive black hole in WISE1029 neither significantly affect the surrounding molecular gas nor the star formation.

    4
    Figure 2: Emission from carbon monoxide (left) and cold dust (right) in WISE1029 observed by ALMA. The image size is 3 square arcsecond. Credit: ALMA (ESO/NAOJ/NRAO), Toba et al.

    There have been many reports saying that the ionized gas outflow driven by the accretion power of a supermassive black hole has an enormous impact on surrounding molecular gas (e.g., *2,3). However, it is a rare case that there is no close interaction between ionized and molecular gas as the researchers are reporting this time. Yoshiki and its team’s result suggests that the radiation from a supermassive black hole does not always affect the molecular gas and star formation of its host galaxy.

    While their result is making the co-evolution of galaxies and supermassive black holes more puzzling, Yoshiki and his team are exciting about revealing the full picture of the scenario. He says that “understanding such co-evolution is crucial for astronomy. By collecting statistical data of this kind of galaxies and continuing in more follow-up observations using ALMA, we hope to reveal the truth.”

    This research was conducted by:

    Yoshiki Toba (Academia Sinica), Shinya Komugi (Kogakuin University), Tohru Nagao (Ehime University), Takuji Yamashita (Ehime University), Wei-Hao Wang (Academia Sinica), Masatoshi Imanishi (National Astronomical Observatory of Japan), Ai-Lei Sun (Academia Sinica, now Johns Hopkins University).

    Notes

    [1] It is a phenomenon where ultraviolet and X-ray radiations make a neutral gas plasma state.

    [2] See the ALMA news Black-Hole-Powered Jets Forge Fuel for Star Formation on February 15, 2017

    [3] See the ALMA news Chaotic Turbulence Roiling ‘Most Luminous Galaxy’ in the Universe on February 18, 2016.

    [4] See the press release from Subaru Telescope Discovering Dust-Obscured Active Galaxies as They Grow on August 26, 2015.

    Science paper:
    No Sign of Strong Molecular Gas Outflow in an Infrared-bright Dust-obscured Galaxy with Strong Ionized-gas Outflow, The Astrophysical Journal.

    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 3:18 pm on February 19, 2018 Permalink | Reply
    Tags: , , , , Chalmers receivers at ALMA, Chalmers University of Technology, , , Radio Astronomy   

    From Chalmers University of Technology: “Receivers from Chalmers will image the distant universe” 

    Chalmers University of Technology

    1
    Receivers in the cryostat: ESO/P. Yagoubov

    Each of the 66 telescopes at Alma has now been equipped with Chalmers receivers.

    From March 1, 2018, when the world’s most powerful telescope will target the most distant universe it is equipped with new receivers that have been developed and produced at Chalmers University. The extremely sensitive instruments also provide new opportunities to search for water in space and in our solar system.

    “Being the best in the world is part of our daily life. There are simply no other options if you wish to participate on this level, “says Victor Belitsky, professor and leader of the Research Group for Advanced Receiver Development (GARD) at Chalmers.

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

    The ALMA telescope consists of 66 dish antennas located 5000 meters above sea level in Chile on a high plateau in the Andes. The dishes work linked together as one telescope and can make far sharper observations than individual radio telescopes can do.

    Each of the 66 antennas has several receivers for observation at different wavelengths. The Chalmers receivers now being used allow observations of light with a wavelength of between 1.4 and 1.8 millimeters – known as Alma’s Band 5. This is microwave radiation, which can be compared with visible light whose longest wavelengths are around 740 nanometres (less than a thousandth of a millimetre).

    “At these frequencies we can observe cold parts of the universe. For example, regions where stars and planets are formed are of great interest. When ALMA’s dishes work together, you get significantly higher resolution than you can do with current optical telescopes, “says Victor Belitsky, whose research group is part of Onsala Space Observatory at the Department of Space, Earth and Environment.

    • The frequencies that are now accessible can give scientists for example a new understanding of how stars, planets and galaxies are born, he says.

    Perfect timing​

    The receivers were developed by the GARD group (click on the image for a larger version with all names) in a project funded by the EU program EC FP6​ in 2006-2012. The timing proved to be perfect. When the first receivers were ready, new research areas were opening up that specifically required ALMA to be able to observe in Band 5.

    Victor and his colleagues had completed six complete receivers, but to handle the order for a further 73, a team from NOVA (Netherlands Research School for Astronomy) was invited to participate. They integrated GARD’s components in the receiver cassettes.

    “Their effort was important to complete the delivery, but the major challenge was to develop the receiver and manufacture the components. We are delivering to the world’s best and most advanced telescope, and thanks to our knowledge and experience, they have now got the best possible receivers”.

    Cool receivers

    The biggest challenge in the production of receivers for radio telescopes is how to reduce noise from their surroundings and get as clean a signal as possible.

    “The noise sets the limit for how weak signals can be detected. It’s like finding the right station on a regular FM-radio, but a million times more sensitive! So, the more we can reduce different types of noise, the more we increase the possibilities for new discoveries in space”, says Victor Belitsky.

    For example, the receivers operate at -269 degrees Celsius, four degrees above absolute zero, to counteract interference from thermal radiation. The image shows the receivers housed in their cryostat, which is designed to maintain such low temperatures.

    Reducing loss of signal in Earth’s atmosphere is also the reason that the ALMA telescope is located at 5000 meters above sea level, in one of the driest places in the world. There is very little water vapor in the atmosphere above the telescope, which means the Band 5 receivers can look for water in space, both nearby and far away, Victor Belitsky explains.

    “There are many uses for our receivers, both in our solar system and in distant galaxies. It depends on which research applications and topics the Alma Research Committee selects, but we know there is a lot of interest to observe water in our own solar system”.

    Sweden among world leaders​

    Sweden’s success with Alma is not limited to delivering instruments. Swedish researchers were among the most frequent users of the telescopes last year, second only to Japan.

    “Second place! That shows the strength and position of Swedish astronomical research in international terms. With the support of instrumentation, we are at one of the world’s leading positions – both in terms of research and technology. That’s something to be proud of”, says Victor Belitsky.

    See the full article here .

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    Chalmers University of Technology (Swedish: Chalmers tekniska högskola, often shortened to Chalmers) is a Swedish university located in Gothenburg that focuses on research and education in technology, natural science, architecture, maritime and other management areas

    The University was founded in 1829 following a donation by William Chalmers, a director of the Swedish East India Company. He donated part of his fortune for the establishment of an “industrial school”. Chalmers was run as a private institution until 1937, when the institute became a state-owned university. In 1994, the school was incorporated as an aktiebolag under the control of the Swedish Government, the faculty and the Student Union. Chalmers is one of only three universities in Sweden which are named after a person, the other two being Karolinska Institutet and Linnaeus University.

     
  • richardmitnick 5:44 pm on February 17, 2018 Permalink | Reply
    Tags: , , , , , , , Radio Astronomy,   

    From ESO: “7. Challenges in Obtaining an Image of a Supermassive Black Hole” 

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    European Southern Observatory

    “Seeing a black hole” has been a long-cherished desire for many astronomers, but now, thanks to the Event Horizon Telescope (EHT) and the Global mm-VLBI Array (GMVA) projects, it may no longer be just a dream.

    Event Horizon Telescope Array

    Arizona Radio Observatory
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    CARMA Array no longer in service
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    IRAM NOEMA interferometer
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    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA
    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA

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    Large Millimeter Telescope Alfonso Serrano

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    Plateau de Bure interferometer

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    To make it possible to image the shadow of the event horizon of Sagittarius A* [SgrA*], many researchers and cutting-edge technologies have been mobilised — because obtaining an image of a black hole is not as easy as snapping a photo with an ordinary camera.

    Sagittarius A* has a mass of approximately four million times that of the Sun, but it only looks like a tiny dot from Earth, 26 000 light-years away.

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

    NASA/Chandra Telescope

    To capture its image, incredibly high resolution is needed. As explained in the fifth post of this blog series, the key is to use Very-Long-Baseline Interferometry (VLBI), a technique that combines the observing power of and the data from telescopes around the world to create a virtual giant radio telescope.

    The resolution of a telescope can be calculated from the radio wavelength the telescope is observing at and the size of the telescope — or in VLBI, the distance between the antennas. However, while actually observing, several kinds of noise and errors interfere with the telescope’s performance and affect the resolution.

    In VLBI, each antenna is equipped with an extremely precise atomic clock to record the time at which radio signals from the target object were received. The gathered data are synthesised using the times as a reference, so that the arrival time of the radio waves to each antenna can be accurately adjusted.

    But this process isn’t always straightforward because the Earth’s atmosphere blocks a certain range of wavelengths. Several kinds of molecules such as water vapour absorb a fraction of radio waves that pass through the atmosphere, with shorter wavelengths more susceptible to absorption. To minimise the effect of atmospheric absorption, radio telescopes are built at high and dry sites, but even then they are still not completely immune from the effect.

    The tricky part of this absorption effect is that the direction of a radio wave is slightly changed when it passes through the atmosphere containing water vapour. This means that the radio waves arrive at different times at each antenna, making it difficult to synthesise the data later using the time signal as a reference. And even worse: since VLBI utilises antennas located thousands of kilometres apart, it has to take into account the differences in the amount of water vapour in the sky above each site, as well as the large fluctuations of water vapour content during the observation period. In optical observations, these fluctuations make the light of a star flicker and lower the resolution. Radio observations have similar problems.

    “We have only a few ways to reduce this effect in VLBI observations,” explains Satoki Matsushita at the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA) of Taiwan. “If there is a compact object emitting intense radiation near the target object, we can remove most of the effect of refraction of radio waves by water vapour by using such an intense radiation source as a reference. However, no such intense reference source has been found near Sagittarius A* so far. And even if there is a reference source, there are still necessary conditions that must be satisfied: the telescopes need to have the ability to observe the target object and reference object at the same time; or the telescopes need to have the high-speed drive mechanism to quickly switch the observation between the target object and the reference object. Unfortunately, not all telescopes participating in the EHT/GMVA observations have this capability. One of the methods to remove the effect is to equip each antenna with an instrument to measure the amount of water vapour, but ALMA is the only telescope that has adopted this method at this point.”

    Another major challenge in imaging a black hole is obtaining a high-quality image. By combining the data collected by antennas thousands of kilometres apart, VLBI achieves a resolution equivalent to a radio telescope several thousands of kilometres in diameter. However, VLBI also has a lot of large blank areas that are not covered by any of the antennas. These missing parts make it difficult for VLBI to reproduce a high-fidelity image of a target object from the synthesised data. This is a common problem for all radio interferometers, including ALMA, but it can be more serious in VLBI where the antennas are located very far apart.

    It might be natural to think that a higher resolution means a higher image quality, as is the case with an ordinary digital camera, but in radio observations the resolution and image quality are quite different things. The resolution of a telescope determines how close two objects can be to each other and yet still be resolved as separate objects, while the image quality defines the fidelity in reproducing the image of the structure of the observed object. For example, imagine a leaf, which has a variety of veins. The resolution is the ability to see thinner vein patterns, while the image quality is the ability to capture the overall spread of the leaf. In normal human experience, it would seem bizarre if you could see the very thin veins of a leaf but couldn’t grasp a complete view of the leaf — but such things happen in VLBI, since some portions of data are inevitably missing.

    1
    This infographic illustrates how ALMA contributes to the EHT observations. With its shorter baseline, ALMA is sensitive to larger scales than the EHT and so ALMA can fill in the lower-resolution, larger-scale structures that the EHT misses. Credit: NRAO

    Researchers have been studying data processing methods to improve image quality for almost as long as the history of the radio interferometer itself, so there are some established methods that are already widely used, while others are still in an experimental phase. In the Event Horizon Telescope (EHT) and the Global mm-VLBI Array (GMVA) projects, which are both aiming to capture the shadow of a black hole’s event horizon for the first time, researchers began to develop effective image analysis methods using simulation data well before the start of the observations.

    2
    A simulated image of the supermassive black hole at the centre of the M87 galaxy. The dark gap at the centre is the shadow of the black hole. Credit: Monika Moscibrodzka (Radboud University)

    The observations with the EHT and the GMVA were completed in April 2017. The data collected by the antennas around the world has been sent to the US and Germany, where data processing will be conducted with dedicated data-processing computers called correlators. The data from the South Pole Telescope, one of the participating telescopes in the EHT, will arrive at the end of 2017, and then data calibration and data synthesis will begin in order to produce an image, if possible. This process might take several months to achieve the goal of obtaining the first image of a black hole, which is eagerly awaited by black hole researchers and the general astronomical community worldwide.

    This lengthy time span between observations and results is normal in astronomy, as the reduction and analysis of the data is a careful, time-consuming process. Right now, all we can do is wait patiently for success to come — for a long-held dream of astronomers to be transformed into a reality.

    Until then, this is the last post in our blog series about the EHT and GMVA projects. When the results become available in early 2018, we’ll be back with what will hopefully be exciting new information about our turbulent and fascinating galactic centre

    See the full article here .

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    ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

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    ESO/Vista Telescope at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level.

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    ESO/NTT at Cerro LaSilla 600 km north of Santiago de Chile at an altitude of 2400 metres.

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    Leiden MASCARA cabinet at ESO Cerro la Silla located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft)

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    ESO TAROT telescope at Paranal, 2,635 metres (8,645 ft) above sea level

    ESO ExTrA telescopes at Cerro LaSilla at an altitude of 2400 metres

     
  • richardmitnick 9:02 am on February 14, 2018 Permalink | Reply
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    From ALMA: “ALMA Observes a Rotating Dust and Gas Donut around a Supermassive Black Hole” 

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

    ALMA

    14 February, 2018

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

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

    Richard Hook
    Public Information Officer, ESO
    Garching bei München, Germany
    Phone: +49 89 3200 6655
    Cell phone: +49 151 1537 3591
    Email: rhook@eso.org

    1
    Artist’s impression of the dusty gaseous torus around an active supermassive black hole. ALMA revealed the rotation of the torus very clearly for the first time. Credit: ALMA (ESO/NAOJ/NRAO)

    High resolution observations with the Atacama Large Millimeter/submillimeter Array (ALMA) imaged a rotating dusty gas torus around an active supermassive black hole. The existence of such rotating donuts-shape structures was first suggested decades ago, but this is the first time one has been confirmed so clearly. This is an important step in understanding the co-evolution of supermassive black holes and their host galaxies.

    2
    The central region of the spiral galaxy M77. The NASA/ESA Hubble Space Telescope imaged the distribution of stars. ALMA revealed the distribution of gas in the very center of the galaxy. ALMA imaged a horseshoe-like structure with a radius of 700 light-years and a central compact component with a radius of 20 light-years. The latter is the gaseous torus around the AGN. Red indicates emission from formyl ions (HCO+) and green indicates hydrogen cyanide emission. Credit: ALMA (ESO/NAOJ/NRAO), Imanishi et al., NASA/ESA Hubble Space Telescope and A. van der Hoeven

    NASA/ESA Hubble Telescope

    Almost all galaxies hold concealed monstrous black holes in their centers. Researchers have known for a long time that the more massive the galaxy is, the more massive the central black hole is. This sounds reasonable at first, but host galaxies are 10 billion times bigger than the central black holes; it should be difficult for two objects of such vastly different scales to directly affect each other. So how could such a relation develop?

    Aiming to solve this shadowy problem, a team of astronomers utilized the high resolution of ALMA to observe the center of spiral galaxy M77. The central region of M77 is an “active galactic nucleus,” or AGN, which means that matter is vigorously falling toward the central supermassive black hole and emitting intense light. AGNs can strongly affect the surrounding environment, therefore they are important objects for solving the mystery of the co-evolution of galaxies and black holes.

    The team imaged the area around the supermassive black hole in M77 and resolved a compact gaseous structure with a radius of 20 light-years. And, the astronomers found that the compact structure is rotating around the black hole, as expected.2
    Motion of gas around the supermassive black hole in the center of M77. The gas moving toward us is shown in blue and that moving away from us is in red. The gas’s rotation is centered around the black hole. Credit: ALMA (ESO/NAOJ/NRAO), Imanishi et al.

    “To interpret various observational features of AGNs, astronomers have assumed rotating donut-like structures of dusty gas around active supermassive black holes. This is called the ‘unified model’ of AGN,” explained Masatoshi Imanishi, from the National Astronomical Observatory of Japan (NAOJ), the lead author on a paper published in the Astrophysical Journal Letters. “However, the dusty gaseous donut is very tiny in appearance. With the high resolution of ALMA, now we can directly see the structure.”

    Many astronomers have observed the center of M77 before, but never has the rotation of the gas donut around the black hole been seen so clearly. Besides the superior resolution of ALMA, the selection of molecular emission lines to observe was key to revealing the structure. The team observed specific microwave emission from hydrogen cyanide molecules (HCN) and formyl ions (HCO+). These molecules emit microwaves only in dense gas, whereas the more frequently observed carbon monoxide (CO) emits microwaves under a variety of conditions [1]. The torus around the AGN is assumed to be very dense, and the team’s strategy was right on the mark.

    “Previous observations have revealed the east-west elongation of the dusty gaseous torus. The dynamics revealed from our ALMA data agrees exactly with the expected rotational orientation of the torus,” said Imanishi.

    Interestingly, the distribution of gas around the supermassive black hole is much more complicated than what a simple unified model suggests. The torus seems to have an asymmetry and the rotation is not just following the gravity of the black hole but also contains highly random motion. These facts could indicate the AGN had a violent history, possibly including a merger with a small galaxy [2]. Nevertheless, the identification of the rotating torus is an important step.

    The Milky Way Galaxy, where we live, also has a supermassive black hole at its center.

    Milky Way Galaxy Credits: NASA/JPL-Caltech/R. Hurt

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

    This black hole is, however, in a very quiet state. Only a tiny amount of gas is accreting onto it. Therefore, to investigate an AGN in detail, astronomers need to observe the centers of distant galaxies. M77 is one of the nearest AGN and a suitable object for peering into the very center in detail.

    These observation results were published as Imanishi et al. ALMA Reveals an Inhomogeneous Compact Rotating Dense Molecular Torus at the NGC 1068 Nucleus in the Astrophysical Journal Letters (2018 February 1 issue, 853, L25).

    The research team members are:

    Masatoshi Imanishi (National Astronomical Observatory of Japan/SOKENDAI), Kouichiro Nakanishi (National Astronomical Observatory of Japan/SOKENDAI), Takuma Izumi (National Astronomical Observatory of Japan), and Keiichi Wada (Kagoshima University).

    Notes

    [1] García-Burillo et al. (2016) observed the distribution and motion of CO with ALMA and did not find clear rotation along the east-west torus direction. Their interpretation is that the turbulent motion is so intense that the east-west oriented rotating motion is not clear. Gallimore et al. (2016) also observed CO emission and found gas motion in the north-south direction. They interpret this as outflowing gas from the black hole.

    [2] Recently, astronomers used the Subaru Telescope to observe M77 and revealed signatures of a merger with a small galaxy billions of years ago. For details, please read the press release Minor Merger Kicks Supermassive Black Hole into High Gear issued in October 2017 from the Subaru Telescope.

    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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