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  • 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.

    NRAO Small
    ESO 50 Large
    NAOJ

     
  • 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
    ESO 50 Large
    NAOJ

     
  • 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.

     
  • richardmitnick 10:34 am on March 15, 2017 Permalink | Reply
    Tags: , , , Cat's Paw Nebula (also known as NGC 6334), , , Protostar Blazes Bright, Radio Astronomy, Reshaping Its Stellar Nursery   

    From ALMA: “Protostar Blazes Bright, Reshaping Its Stellar Nursery” 

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

    15 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
    ALMA image of the glowing dust inside NGC 6334I, a protocluster containing an infant star that is undergoing an intense growth spurt, likely triggered by an avalanche of gas falling onto its surface. ALMA (ESO/NAOJ/NRAO); C. Brogan, B. Saxton (NRAO/AUI/NSF).

    A massive protostar, deeply nestled in its dust-filled stellar nursery, recently roared to life, shining nearly 100 times brighter than before. This outburst, apparently triggered by an avalanche of star-forming gas crashing onto the surface of the star, supports the theory that young stars can undergo intense growth spurts that reshape their surroundings.

    Astronomers made this discovery by comparing new observations from the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile with earlier observations from the Submillimeter Array (SMA) in Hawaii.


    CfA Submillimeter Array Mauna Kea, Hawaii, USA

    “We were amazingly fortunate to detect this spectacular transformation of a young, massive star,” said Todd Hunter, an astronomer at the National Radio Astronomy Observatory (NRAO) in Charlottesville, Virginia, USA, and lead author on a paper published in the Astrophysical Journal Letters. “By studying a dense star-forming cloud with both ALMA and the SMA, we could see that something dramatic had taken place, completely changing a stellar nursery over a surprisingly short period of time.”

    In 2008, before the era of ALMA, Hunter and his colleagues used the SMA to observe a small but active portion of the Cat’s Paw Nebula (also known as NGC 6334), a star-forming complex located about 5,500 light-years from Earth in the direction of the southern constellation Scorpius. This nebula is similar in many respects to its northern cousin, the Orion Nebula, which is also brimming with young stars, star clusters, and dense cores of gas that are on the verge of becoming stars. The Cat’s Paw Nebula, however, is forming stars at a faster rate.

    2
    Inside the Cats’s Paw Nebula as seen in an infrared image from NASA’s Spitzer Space Telescope (left), ALMA discovered that an infant star is undergoing an intense growth spurt, shining nearly 100 brighter than before and reshaping its stellar nursery (right). Credit: ALMA (ESO/NAOJ/NRAO), T. Hunter; C. Brogan, B. Saxton (NRAO/AUI/NSF); NASA Spitzer.


    NASA/Spitzer

    The initial SMA observations of this portion of the nebula, dubbed NGC 6334I, revealed what appeared to be a typical protocluster: a dense cloud of dust and gas harboring several still-growing stars.

    Young stars form in these tightly packed regions when pockets of gas become so dense that they begin to collapse under their own gravity. Over time, disks of dust and gas form around these nascent stars and funnel material onto their surfaces helping them grow.

    This process, however, may not be entirely slow and steady. Astronomers now believe that young stars can also experience spectacular growth spurts, periods when they rapidly acquire mass by gorging on star-forming gas.

    The new ALMA observations of this region, taken in 2015 and 2016, reveal that dramatic changes occurred toward a portion of the protocluster called NGC 6334I-MM1 in the years since the original SMA observations. This region is now about four times brighter at millimeter wavelengths, meaning that the central protostar is nearly 100 times more luminous than before.

    The astronomers speculate that leading up to this outburst, an uncommonly large clump of material was drawn into the star’s accretion disk, creating a logjam of dust and gas. Once enough material accumulated, the logjam burst, releasing an avalanche of gas onto the growing star.

    4
    Comparing observations by two different millimeter-wavelength telescopes, ALMA and the SMA, astronomers noted a massive outburst in a star-forming cloud. Because the ALMA images are more sensitive and show finer detail, it was possible to use them to simulate what the SMA could have seen in 2015 and 2016. By subtracting the earlier SMA images from the simulated images, astronomers could see that a significant change had taken place in MM1 while the other three millimeter sources (MM2, MM3, and MM4) are unchanged. ALMA (ESO/NAOJ/NRAO); SMA, Harvard/Smithsonian CfA

    This extreme accretion event greatly increased the star’s luminosity, heating its surrounding dust. It’s this hot, glowing dust that the astronomers observed with ALMA. Though similar events have been observed in infrared light, this is the first time that such an event has been identified at millimeter wavelengths.

    To ensure that the observed changes were not the result of differences in the telescopes or simply a data-processing error, Hunter and his colleagues used the ALMA data as a model to accurately simulate what the SMA — with its more modest capabilities — would have seen if it conducted similar operations in 2015 and 2016. By digitally subtracting the actual 2008 SMA images from the simulated images, the astronomers confirmed that there was indeed a significant and consistent change to one member of the protocluster.

    “Once we made sure we were comparing the two sets of observations on an even playing field, we knew that we were witnessing a very special time in the growth of a star,” said Crystal Brogan, also with the NRAO and co-author on the paper.

    Further confirmation of this event came from complementary data taken by the Hartebeesthoek Radio Astronomy Observatory in South Africa.


    Hartebeesthoek Radio Astronomy Observatory, located west of Johannesburg South Africa

    This single-dish observatory was monitoring the radio signals from masers in the same region. Masers are the naturally occurring cosmic radio equivalent of lasers. They are powered by a variety of energetic processes throughout the universe, including outbursts from rapidly growing stars.

    The data from the Hartebeesthoek observatory reveal an abrupt and dramatic spike in maser emission from this region in early 2015, only a few months before the first ALMA observation. Such a spike is precisely what astronomers would expect to see if there were a protostar undergoing a major growth spurt.

    “These observations add evidence to the theory that star formation is punctuated by a sequence of dynamic events that build up a star, rather than a smooth continuous growth,” concluded Hunter. “It also tells us that it is important to monitor young stars at radio and millimeter wavelengths, because these wavelengths allow us to peer into the youngest, most deeply embedded star-forming regions. Catching such events at the earliest stage may reveal new phenomena of the star-formation process.”

    This research is presented in a paper titled “An extraordinary outburst in the massive protostellar system NGC6334I-MM1: Quadrupling of the millimeter continuum,” by T.R. Hunter et al., published in the Astrophysical Journal Letters [https://arxiv.org/abs/1701.08637].

    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 10:25 am on March 10, 2017 Permalink | Reply
    Tags: , , , , , Mia Baquiran, Radio Astronomy,   

    From CSIRO: Women in STEM – “One woman’s role in designing the world’s largest radio telescope” Mia Baquiran 

    CSIRO bloc

    Commonwealth Scientific and Industrial Research Organisation

    10th March 2017
    Helen Sim

    1
    Mia Baquiran. When they flick the switch on the world’s largest telescope, one woman’s work will come to life.

    If it takes a village to raise a child, it takes a planet – or at least ten countries – to build the the world’s largest radio telescope, the Square Kilometre Array.

    The Square Kilometre Array, or SKA, is a next-generation radio telescope that will be vastly more sensitive than the best present-day instruments. It will give astronomers remarkable insights into the formation of the early Universe, including the emergence of the first stars, galaxies and other structures.

    Consisting of thousands of antennas linked together by high bandwidth optical fibre, the SKA will require new technologies and progress in fundamental engineering. The telescope’s design and development is being led by the international SKA Organisation.

    Radio telescopes add to observations made by optical and other telescopes by revealing different information about stars, galaxies and gas clouds. Because radio waves can pass through clouds of dust and gas, radio telescopes are able to observe objects and processes not visible to other telescopes.

    2
    An artist’s impression of the Square Kilometre Array’s antennas in Australia. ©SKA Organisation

    Construction is due to start in 2018 and around the globe 11 groups, all with members from several countries, are working feverishly on different aspects of the project to make it come together.

    Australia has a presence in several of these groups, and indeed leads two of them. Our very own Mia Baquiran is one of the researchers working on this exciting project.

    She spends her days in a quiet, ground-floor office in a leafy suburb of Sydney, working on systems that will go into the international SKA radio telescope.

    Mia’s role in this ‘moon-shot’ project concerns a telescope called ‘SKA Low’, an assembly of more than a quarter of a hundred thousand low-frequency antennas that will be housed at CSIRO’s Murchison Radio-astronomy Observatory in Western Australia.

    3
    CSIRO’s ASKAP antennas under construction at the Murchison Radio-astronomy Observatory in Western Australia

    SKA Low has no moving parts but it is still a complex beast. The signals from the antennas have to be brought together and compared with each other (‘correlated’) to create a view of the sky.

    Mia is working on the system (the correlator and beamformer) that does this. She writes ‘permanent’ software (firmware) for controlling the subsystems of the correlator and beamformer.

    4
    Our research engineer Mia Baquiran is working on the software that will create a view of the sky using the SKA Low radio telescope.

    So how did she get into this space you might ask?

    “When I was thinking about what I wanted to do at university I didn’t have that much direction,” Mia said. “Really the only thing that got me excited was the concept of engineering, being able to develop things and understanding how things work.”

    She was always interested in physics and robotics appealed too, so she headed for a degree in mechatronics, a field that brings together mechanical engineering, electronics and software.

    After finishing her studies at UNSW in 2012 she worked at a small software company, then joined our astronomy and space science research area.

    Mia loves problem solving. “There’s always that wonderful moment when you finally find a solution,” she said.

    She’s also curiosity-driven. “I like the idea that I can learn something new every day,” she said. “Engineering is constantly changing, so you have to become a lifelong learner.”

    “I do enjoy the opportunity to learn from people who are more experienced than me, and that’s definitely well-facilitated in CSIRO.”

    Because the correlator and beamformer project is international Mia has had the opportunity to visit the Netherlands to work with colleagues there.

    The SKA will give radio astronomers a view of the past a million years after the Big Bang, when the universe first evolving to what is referred to as the “cosmic dawn”.

    But what’s in store for Mia in her future?

    “I’d like to continue in electronics and FPGA (field programmable gate array) design,” she said.

    “Ideally I’d like to continue in radio astronomy, because we’re in a special position being in Australia, where it’s one of the fields that we’re world leaders in.”

    Find out more about how CSIRO is helping to bring the Square Kilometre Array to life.

    See the full article here .

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

     
  • richardmitnick 10:18 am on March 6, 2017 Permalink | Reply
    Tags: Hydrogen Epoch of Reionization Array (HERA) at the Karoo desert site South Africa, Radio Astronomy, SKA Africa   

    From SKA Africa: “Karoo’s HERA radio telescope attracts even more international funding” 

    SKA Square Kilometer Array

    SKA

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    SKA Africa

    6 March 2017
    Lorenzo Raynard
    SKA SA Head: Communication and Stakeholder Relations
    Email: lraynard@ska.ac.za
    Mobile: +27 (0)71 454 0658

    19 dishes, UC Berkeley Hydrogen Epoch of Reionization Array (HERA), at the Karoo desert site, South Africa
    Hydrogen Epoch of Reionization Array (HERA), at the Karoo desert site, South Africa

    The Hydrogen Epoch of Reionization Array (HERA) radio telescope, located only a few kilometres from the MeerKAT radio telescope, was awarded a grant from the Gordon and Betty Moore Foundation in the US to the value of $5.8 million, equivalent to approximately R75 million.

    SKA Meerkat telescope, 90 km outside the small Northern Cape town of Carnarvon, SA
    SKA Meerkat telescope, 90 km outside the small Northern Cape town of Carnarvon, SA

    The construction of HERA started in 2015 and already 35 of the 14-metre diameter dishes have been erected. In September 2016, the National Science Foundation (NSF) invested $9.5 million (equivalent to approximately R124 million) in the project and HERA was granted the status of a Square Kilometre Array (SKA) precursor telescope. The NSF funding allowed the array to expand to 240 radio dishes by 2018. This additional funding injection from the Gordon and Betty Moore Foundation will allow HERA to expand even further to 350 dishes.

    This innovative radio telescope will be instrumental in detecting the distinctive signature that would allow astronomers to understand the formation and evolution of the very first luminous sources: the first stars and galaxies in the Universe – a period the scientists call the Epoch of Reionization (EoR).

    With the grant from the Gordon and Betty Moore Foundation, the sensitivity of the array can be increased and potentially detect signals coming from a time before the EoR in the history of the Universe, the Cosmic Dawn, roughly 400 million years after the Big Bang. HERA will be able to access a cosmological signal roughly 100,000 times fainter than emissions from the Milky Way and nearby galaxies.

    Dr Gianni Bernardi, SKA South Africa senior astronomer working on HERA, says: “The new funding increases the sensitivity of HERA by adding 110 dishes – 350 dishes in total. This increase in collecting area provides the sufficient sensitivity to attempt imaging large ionized bubbles rather than measuring ‘only’ their statistical properties.”

    Using this next-generation instrumentation for 21-cm cosmology – the wavelength of neutral hydrogen gas radio waves – HERA will probe the 3D structure of the Universe during the very first appearance of stars, galaxies and black holes. This first generation of hot massive stars and black-hole binaries filled the intergalactic medium with X-rays.

    “Observations at the lowest radio frequencies (<100 MHz), allows for observations of the epoch that precedes cosmic reionization where X-rays are expected to have heated the intergalactic medium. As X-rays are expected to be generated by accretion on black holes, observations of this epoch will directly probe the properties of the first black holes formed in the Universe." says Bernardi. HERA comprises a close-packed array of fixed parabolic reflector elements (dishes). The centre position of each dish is determined by the placement of a concrete hub. These hubs constrain radial PVC spars, tensioned into approximate parabolas against a rim, which is supported by utility (telephone) poles. Welded mesh panels are installed on these spars to form the reflector surface. Project Engineer Kathryn Rosie is responsible for HERA's construction in the Karoo and says: "Five local residents, who have been part of the HERA construction crew since 2015, have recently taken up positions as HERA team leaders in anticipation of the crew expansion for the 'big build' in early 2017. In addition to maintaining construction activities, they now have the added responsibility to train new construction team members. The build-out plan for the next construction phase sees five teams working in parallel to achieve the build targets, which require an output of approximately 100 dishes per year, and it is expected that the entire crew contingent will be made up of Karoo residents." Rosie says: "In excess of R1.7 million has been spent thus far with local suppliers in the Karoo to purchase the material with which the telescope is being built. We are proud of the fact that all of the build materials, items, and labour involved in the construction of the reflector elements have been sourced from within South Africa, with most of our bulk materials being sourced from within the Karoo region." Dr Rob Adam, Managing Director of SKA South Africa, says: "The SKA project in the Karoo is progressing very well and this additional funding injection is evidence of the confidence the international community has in the excellent skills and results we are demonstrating. SKA SA remains committed in ensuring that local communities and businesses benefit from the construction of radio telescopes in the Karoo and HERA is a fine example of that." Dr Adam adds: "It is particularly fitting that the man who originated Moore's Law, Gordon Moore, is affiliated to the SKA project through this Gordon and Betty Moore Foundation grant." Gordon Moore is the chairman and co-founder of the Gordon and Betty Moore Foundation. Gordon Moore predicted in 1965 that there will be a steady shrinking of computer chip circuitry. This idea that transistor density would double with each new generation of technology is referred to as the Moore's Law. Notes to Editors

    The HERA collaboration consists of Arizona State University, Brown University, Cambridge University, the Massachusetts Institute of Technology, the National Radio Astronomy Observatory, Scuola Normale Superiore (Pisa), Square Kilometre Array South Africa (SKA SA), University of California at Berkeley, the University of California at Los Angeles, the University of Pennsylvania, and the University of Washington. Participating South African institutions include Rhodes University, the University of KwaZulu-Natal, the University of the Western Cape and the University of the Witwatersrand.

    HERA is one of a number of low frequency radio telescopes, including the Murchison Widefield Array (MWA) in Australia and the Low-Frequency Array (LOFAR) in the Netherlands that are pathfinders for SKA1 LOW to be located in Australia.

    SKA Murchison Widefield Array,SKA Murchison Widefield Array, Boolardy station in outback Western Australia, at the Murchison Radio-astronomy Observatory (MRO)
    SKA Murchison Widefield Array,SKA Murchison Widefield Array, Boolardy station in outback Western Australia, at the Murchison Radio-astronomy Observatory (MRO)

    SKA LOFAR core near Exloo, Netherlands
    SKA LOFAR core near Exloo, Netherlands

    The SKA is an international effort to build the world’s largest radio telescope – one hundred times more sensitive than any current radio telescope. The scale of the SKA represents a huge leap forward in both engineering and research and development towards building and delivering a unique instrument. As one of the largest scientific endeavours in history, the SKA will bring together a wealth of the world’s finest scientists, engineers and policy makers to bring the project to fruition. SKA will be built in two phases – SKA1 and SKA2 – starting in 2018. SKA1 will include two components – SKA1 MID (to be built in South Africa) and SKA1 LOW (to be built in Australia); they will observe the Universe at different radio frequencies.

    See the full article here .

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    SKA CSIRO  Pathfinder Telescope
    SKA ASKAP Pathefinder Telescope

    SKA Meerkat telescope
    SKA Meerkat Telescope

    SKA Murchison Widefield Array
    SKA Murchison Wide Field Array

    About SKA

    The Square Kilometre Array will be the world’s largest and most sensitive radio telescope. The total collecting area will be approximately one square kilometre giving 50 times the sensitivity, and 10 000 times the survey speed, of the best current-day telescopes. The SKA will be built in Southern Africa and in Australia. Thousands of receptors will extend to distances of 3 000 km from the central regions. The SKA will address fundamental unanswered questions about our Universe including how the first stars and galaxies formed after the Big Bang, how dark energy is accelerating the expansion of the Universe, the role of magnetism in the cosmos, the nature of gravity, and the search for life beyond Earth. Construction of phase one of the SKA is scheduled to start in 2016. The SKA Organisation, with its headquarters at Jodrell Bank Observatory, near Manchester, UK, was established in December 2011 as a not-for-profit company in order to formalise relationships between the international partners and centralise the leadership of the project.

    The Square Kilometre Array (SKA) project is an international effort to build the world’s largest radio telescope, led by SKA Organisation. The SKA will conduct transformational science to improve our understanding of the Universe and the laws of fundamental physics, monitoring the sky in unprecedented detail and mapping it hundreds of times faster than any current facility.

    Already supported by 10 member countries – Australia, Canada, China, India, Italy, New Zealand, South Africa, Sweden, The Netherlands and the United Kingdom – SKA Organisation has brought together some of the world’s finest scientists, engineers and policy makers and more than 100 companies and research institutions across 20 countries in the design and development of the telescope. Construction of the SKA is set to start in 2018, with early science observations in 2020.

     
  • richardmitnick 1:58 pm on March 2, 2017 Permalink | Reply
    Tags: , , Jicamarca Radio Observatory, , Radio Astronomy, Space physics   

    From Eos: “After Decades, High-Altitude Observations Revived at Jicamarca” 

    AGU bloc

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    Eos news bloc

    Eos

    3.2.17
    Mark Zastrow

    1
    Dipoles of the telescope at Jicamarca Radio Observatory near Lima, Peru. Construction of the observatory was completed in 1962, around the time this photo was taken. Credit: Alastair Philip Wiper/VIEW

    When the Jicamarca Radio Observatory made its first observations of Earth’s ionosphere in the early 1960s, it was one of the most impressive facilities in the nascent field of space physics. Its massive square array of dipole antennas was laid out in the Peruvian desert east of Lima, nearly 300 meters on each side. The enormous radar facility was designed to probe the ionosphere directly above Earth’s equator; electrons in the ionosphere scatter the radar beams, but a faint return signal gives an indication of their density.

    In its initial observing runs, scientists included measurements at very high altitudes, an exercise meant to map out the space surrounding Earth. They also pushed the facility to its limits, requiring powerful radar pulses from all four of its transmitters and many people to operate them. Soon, however, high-altitude operations were canceled; the last runs occurred in 1965.

    As the facility began to focus on more popular areas of research, the unpublished high-altitude records languished. Many were lost. The details of the observations and analysis—such as which filtering methods, if any, were used—faded away, limiting the surviving data’s usefulness. Eventually, the capability to reproduce them was lost, as transmitters fell offline and Jicamarca focused on targets closer to the ground.

    Today, more than 50 years later, interest in high-altitude observations is on the rise, this time driven by the desire to understand how plasma behaves during geomagnetic storms. Jicamarca remains one of the most important space physics radar facilities, and fortunately, recent upgrades have restored the facility’s ability to carry out high-altitude observations. On 31 May 2016, Jicamarca fired up its transmitters and focused its antennas on high-altitude incoherent scatter in a study conducted by Hysell et al.

    In a 24-hour period of observations, the team found that Jicamarca could profile the electron density up to an altitude of roughly 6300 kilometers. That’s high enough to usefully overlap with data from ground-based magnetometers, which can cover a range from roughly 3000 kilometers to 16,000 kilometers. The data analysis also revealed that different filtering methods did not change the results much, which makes it easier to interpret historical data.

    The authors used just two of Jicamarca’s four transmitters, all of which have been restored to operational status. Even with only two transmitters, the data quality was similar to the 1965 data, with a slightly better dynamic range. The team notes that future observations using all four transmitters will be more sensitive and should push the observatory’s range occasionally up to 10,000 kilometers. (Journal of Geophysical Research: Space Physics, https://doi.org/10.1002/2016JA023569, 2017)

    See the full article here .

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    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 2:24 pm on February 27, 2017 Permalink | Reply
    Tags: , , Radio Astronomy, , SKA: Tooling up down under for the world's most powerful telescope   

    More about SKA – “SKA: Tooling up down under for the world’s most powerful telescope” 

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    COSMOS

    27 February 2017
    Elizabeth Finkel

    1
    SKA will not only take us to the edge of the universe, it will revolutionise computing. Dragonfly Media / CSIRO

    On a flat, red mulga plain in the outback of Western Australia, preparations are under way to build the most audacious telescope astronomers have ever dreamed of – the Square Kilometre Array (SKA).

    SKA Square Kilometer Array

    Next-generation telescopes usually aim to double the performance of their predecessors. The Australian arm of SKA will deliver a 168-fold leap on the best technology available today, to show us the universe as never before. It will tune into signals emitted just a million years after the Big Bang, when the universe was a sea of hydrogen gas, slowly percolating with the first galaxies. Their starlight illuminated the fledgling universe in what is referred to as the “cosmic dawn”.

    “It is the last non-understood event in the history of the universe,” says Stuart Wyithe, a theoretical astrophysicist at the University of Melbourne in Australia.

    Like any dream, realisation is the hard part. In 2018, when the first of 130,000 Christmas-tree-like antennae is deployed on the sandy plains of Murchison, an almost uninhabited district of 50,000 square kilometres, it will mark 28 years since its conception.

    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia
    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia

    SKA Murchison Widefield Array
    SKA Murchison Widefield Array

    Epic battles have brought the project to this point – most famously the six-year contest between countries to host the telescope. Australia and South Africa ended up sharing the prize. The SKA’s telescope in South Africa will be built on another flat, red flat plain – the Karoo region of the North Cape.

    SKA Icon

    It has somewhat less lofty ambitions – its dishes will probe only halfway to the edge of the universe. Its moniker, SKA-mid, denotes the mid-range frequencies of radio waves stretched across this distance.

    Australia’s SKA-low, by contrast, will tune into the low frequencies emanating from the extremities of the cosmos. Together the two telescopes will represent “the largest science facility on the planet,” says SKA director-general and radio astronomer Phil Diamond, who is based at Jodrell Bank Observatory in the UK.

    3
    Artist’s impression of the expansion to the current headquarters at Jodrell Bank at U Manchester proposed by the UK

    The game-changing technology that will allow us to hear the whispers of newborn stars against the cacophony of the universe doesn’t involve grinding mirrors to atom-thin smoothness or constructing dishes the size of sports fields. The disruptive technology here is supercomputing.

    Once SKA-low is running, it will generate more data every day than the world’s internet traffic. Dealing with this deluge is a challenge being tackled by hefty global collaborations of academia and private enterprise – and it is by no means clear how it will be solved. “It’s a scale no one has attempted before,” says Peter Quinn, a computational astrophysicist at the University of Western Australia, and director of the International Centre for Radioastronomy Research (ICRAR) in Perth.

    ICRAR Logo

    While international mega-science projects have been tackled before – think the European Organisation for Nuclear Research (CERN), which operates the world’s largest particle accelerator, the Large Hadron Collider – when it comes to the SKA, the potential world-changing spin-offs have never been so blazingly obvious.

    CERN didn’t just find the Higgs boson – computer scientist Tim Berners-Lee created the World Wide Web to manage its information sharing. Wi-Fi was the spin-off when Australian CSIRO astronomers developed ways to realign scrambled radio signals from black holes.

    Mega-corporations such as CISCO, Woodside, Chevron, Rio Tinto and Google are already positioned to collaborate with SKA astronomers around the world.

    A science project of this grandeur, managed across 10 countries, involving dozens of specialist technical consortia and thousands of people, is challenging enough. The question of how to divvy up the pie for construction contracts and the commercial spin-offs that follow adds a whole new, complicated layer.

    But astronomers have a great track record when it comes to teasing their way through gnarly collaborations to deliver triumphs such as the Hubble Space Telescope and the Atacama Large Millimeter Array.

    NASA Hubble Telescope
    NASA/ESA Hubble Telescope

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

    After nearly 25 years of wrangling, the signs are that the first binding SKA treaty will be signed early next year, committing the 10 member countries – Australia, Canada, China, India, Italy, New Zealand, South Africa, Sweden, the Netherlands and the UK – to funding and contracts for the 2018 rollout.

    Even with the treaty, SKA will remain a confusing beast: not one telescope but two, located in two countries, with headquarters in a third – the UK. Despite the name, neither of the Phase 1 telescopes slated for construction actually boasts a square kilometre of collecting area. That won’t be realised until Phase 2 of the project, negotiations for which have yet to begin.

    Nevertheless, as the gears of the vast project slowly grind into action, Australia is bracing to host its first global mega-science project. “It will be our CERN downunder,” says CSIRO astronomer Sarah Pearce, Australia’s science representative to the SKA board. But, she adds, “don’t expect a tour. It’s here precisely because there are very few people.”

    5
    The 200 dishes of SKA-mid to be rolled out in South Africa will probe half way to the edge of the universe. SKA Organisation / Eye Candy Animation (Artist’s impression)

    An idea takes root

    The curious thing about astronomy is that telescopes, as they grow more powerful, turn into time machines. When Galileo peered at Jupiter, he saw it as it appeared some 42 minutes earlier – the time it took for its light to reach him. Hubble’s iconic image of the Horsehead Nebula in the constellation of Orion is a snapshot of how it looked 1,500 years ago.

    Horsehead Emission nebula
    Horsehead Emission nebula

    The astronomers who conceived the SKA had their sights set way beyond the 100,000-light-year dimensions of our own galaxy. The faint signals they seek began their journey more than 13 billion years ago, just a few million years after the Big Bang.

    At that point, the hot plasma of electrons and protons had cooled enough to fuse and form the simplest atom – hydrogen. Except for a slight ripple here or there, our universe was a featureless sea of it. Today, things are different – the sea is dotted with galaxies. But how did these galactic islands form? To find out requires a telescope that can look back to the rippling hydrogen sea of 13 billion years ago. “That’s why the SKA was originally called the ‘hydrogen telescope’,” Quinn says.

    Those who imagined the SKA had a lust for hydrogen. Their appetite had been whet by the Very Large Array (VLA), 27 dishes lying 80km west of Socorro, in New Mexico.

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

    Now known as the Jansky VLA, the telescope generated some of the first detailed maps of atomic hydrogen. The bond between hydrogen’s electron and proton emits a unique 21-centimetre radio wave. Because the universe is expanding, the waves emitted from outer space have stretched by the time they reach us. The futher away, the greater the stretching; hydrogen waves emanating from the edge of the universe measure 1.5m by the time they reach Earth. It’s known as the Doppler effect; on Earth, we experience it when we hear the sound of an ambulance siren deepen as it speeds away, its sound wave stretching as it goes.

    In 1990, on the 10th anniversary of the VLA, the world’s radio astronomers met to celebrate one of the New Mexico facility’s crowning achievements – mapping hydrogen in nearby galaxies. Ron Ekers, an Australian former director of the array, recalls that “everyone was on a high”.

    Not content to rest on their laurels, a small group of visionary astronomers wondered how far the technology could be pushed. Egged on, Peter Wilkinson from the University of Manchester in Britain pitched the idea of reaching out to galaxies at the edge of the universe. A total collecting area of one square kilometre, he figured, should do the job.

    The audacity of the proposal was amazing, Quinn says: “Most telescope improvements aim for a two-to-three-fold increase; this proposal represented a 10,000-fold increase.” That figure reflected a 50-fold increase in sensitivity multiplied by a 200-fold increase in field of view. “The goal was to see a milky way at the edge of the universe,” Quinn adds – and to scour the entire southern sky.

    The breakthrough technology needed to enable this leap did not lie in fancy new telescope designs, but in the explosion of computing power and techniques able to handle massive amounts of data.

    The receivers themselves could be little more than antennas. Tuned to radio wavelengths, they would pick up the extra-long waves of distant hydrogen – coincidentally the same wavelength used by many FM radio stations. “This is where the early universe is broadcasting,” says Quinn. “You just can’t hear it because it’s buried in the crackle.”

    The more antennae, the greater the sensitivity – hence the planned one square kilometre of collecting surface. But the antennae don’t need to be all in one spot. Indeed, the more spread out they are, the sharper the focus.

    How does a forest of radio antennae figure out where in the sky a signal has come from? Interferometry, a technique developed by British and Australian radio astronomers in the 1940s, is the key. It relies on the principle that each antenna in an array receives a signal at a slightly different time. For instance, radio waves coming from the easterly part of the sky hit the eastern-most antennae earlier than those lying further west. By electronically tweaking the delay on each, the entire forest could be made to point in a particular direction of the sky.

    But using interferometry to tune into signals from the edge of the universe would have required filtering astronomical amounts of data; and that was a challenge yet to be mastered.

    6
    Like a forest of metal pine trees: an artist’s impression of some of the 130,000 antennae of SKA-low to be assembled on the red plains of Murchison. They will probe to the edge of the universe.
    SKA Organisation / Eye Candy Animation

    The tussle

    In 2000, a SKA steering committee led by Ekers invited proposals for a home for the telescope. Five countries responded. To help their bid, some built serious prototypes known as “pathfinders”. It resulted in an astronomical bonanza. Australia built the majestic dishes of the Australian Square Kilometre Array Pathfinder (ASKAP) and the antenna forest of the Murchison Widefield Array (MWA).

    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia
    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia

    South Africa built the seven dishes of KAT-7 and is building the larger SKA Meerkat telescope, 90 km outside the small Northern Cape town of Carnarvon, SA.
    “SKA Meerkat telescope, 90 km outside the small Northern Cape town of Carnarvon, SA

    China began work on a prototype which paved the way for the Five-hundred-metre Aperture Spherical radio Telescope (FAST), the largest single radio dish in the world.

    FAST Chinese Radio telescope , being built at Guizhou Province, China
    FAST Chinese Radio telescope , being built at Guizhou Province, China

    FAST radio telescope, now operating  located in the Dawodang depression in Pingtang county Guizhou Province, South China
    “FAST radio telescope, now operating located in the Dawodang depression in Pingtang county Guizhou Province, South China

    Geography worked against some of the contestants. The Chinese site wasn’t flat enough. The joint Brazilian-Argentinian bid was let down by a turbulent ionosphere – the uppermost layer of the atmosphere – which distorted the sought-after low frequency radio waves.

    By 2006, Australia and South Africa were the last countries standing. Both laid claim to vast unpopulated regions, free of radio wave interference and with relatively placid ionospheres.

    The South African site’s higher elevation was in its favour. Australia, on the other hand, had an impressive track record in radio astronomy. It boasted some of the world’s first interferometers, built in the 1940s at Dover Heights south of Sydney, and the iconic CSIRO Parkes telescope, operating since 1961.

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

    The contest was fierce, and for good reason: SKA’s benefits clearly stretched far beyond astronomy. “The devices and algorithms developed to pursue SKA’s goals may be the next Wi-Fi, the next multi-trillion dollar technology market,” says Steven Tingay, the former director of the MWA who now leads Italy’s SKA involvement. Whichever country hosted the SKA would be at the heart of the action, attracting and training the next generation of engineers and scientists in advanced manufacturing, telecommunications and high-performance computing.

    Accompanied by the sort of media attention usually reserved for a football grand final, a competitive and secretive bidding process ensued.

    In May 2012, members of the SKA organisation voted to split the array between the Australian and African sites. The South African telescope would observe radio waves from 350 MHz to 14 gigahertz, enabling it to detect signals up to six billion light-years away – a still sparse chapter in the universe’s life story. It would use dishes like those of the JVLA, but dramatically increase speed and sensitivity.

    Australia’s array would detect frequencies in the range of 50 to 350 MHz – ideal for detecting hydrogen signals from the edge of the universe.

    Both would rely on the development of disruptive new computation techniques.

    “We believe we know how to do it, but I’m not hiding the fact that it’s a challenge,” Diamond says.

    7
    The Murchison Widefield Array is the prototype for the SKA-low. This composite image from the GLEAM survey shows how the Milky Way appears at radio wavelengths.
    Radio image: Natasha Hurley-Walker (ICRAR / Curtin) / GLEAM Team. MWA tile and landscape: Dr John Goldsmith / Celestial Visions.

    Building it

    Getting to the Australian site of the SKA gives the words “isolation” and “quiet” whole new meanings. First, you make your way to Perth, itself one of the most isolated cities in the world. Then it’s another one-hour flight to the 35,000-strong port town of Geraldton. From there, bump around for four dusty hours in a four-wheel-drive until finally, on the horizon, you see a succession of towering white 12-metre telescope dishes.

    You have arrived at the Murchison Radio-astronomy Observatory. The 36 dishes comprise ASKAP. Despite the name, they are not the prototype for SKA-low. That honour goes to the MWA, a rather less majestic affair that lies hidden in the nearby mulga scrub: 2,048 squat, wiry antennae, resembling a swarm of giant spiders. Unlike ASKAP, the MWA has no moving parts to point to different parts of the sky. That’s because this is a software telescope. It relies on a computer to program different delays into the antennae so signals from the same patch of sky are collected at the same time.

    Amid great fanfare, MWA first came online in mid-2013. According to director Randall Wayth, it has blazed the trail for SKA-low. It is tuned to receive signals from the early universe within the bandwidth of 80 to 300 MHz. It does not have the sensitivity to detect features of the cosmic dawn, but its impressive 30-degree field of view allows it to map the entire visible sky over a few nights. The Galactic and Extragalactic All-sky MWA (GLEAM) survey, for instance, mapped bubbles of ionised hydrogen gas and quasars from up to six billion light years away.

    Two trail-blazing aspects of its operation are key to SKA-low. The first is that it has pioneered methods to adjust for the distorting effects of the ionosphere above Murchison. “It’s like trying to see something at the bottom of a rippling pool,” explains Wayth. “Luckily for us, it’s usually just small ripples.”

    Filtering out the ripples of the ionosphere is just one step in a multipronged data-processing operation whose ultimate aim is to deliver sharp images of the ancient universe.

    Another early step reduces the noise inherent in the system. The heart of every radio telescope is an onsite computer known as a correlator. Developed through a partnership with IBM and Cisco, the MWA’s correlator compares signals from each of the 2,048 antennae. Noise is random; real signals are correlated. By accepting only correlated signals, this step reduces the data to a manageable 1% of the initial deluge.

    The next phase takes place off-site. An 800 km optic fibre ferries the pre-filtered data from the desert to the Pawsey Supercomputing Centre in Perth. A mirror link also takes it to collaborators at the Massachusetts Institute of Technology in Boston, and Victoria University of Wellington in New Zealand, to be used by some 35 different science projects.

    Just as a human brain must process vast amounts of data into a meaningful representation of the world, these supercomputers turn the MWA radio wave signals into pictures of the universe. There are data from across different regions of the sky, and across tens of thousands of frequencies. It is sifted by setting windows to extract “cubes” of information. Like pixels on a screen, they provide an image of the universe.

    The MWA’s coarse resolution means its cubes can’t produce a sharp image. SKA, with its 100-fold greater sensitivity and 40-fold increase in resolution, will provide more cubes to show us what is actually there. But in order to do that, it must solve the data deluge problem.

    8
    The Pawsey Supercomputing Centre in Perth, transforms huge amounts of raw data into images of the universe. Pawsey Supercomputing Centre

    Scaling up to SKA

    The antenna design selected for SKA is not the MWA’s squat spider, but one that resembles a pine tree – the so-called log periodic design. Different rung lengths on the tree enable it to resonate in a wide range of frequencies – from 50 to 650 MHz. (MWA typically manages 80 to 300 MHz.) SKA will deploy 130,000 of them.

    But that won’t deliver the eponymous square kilometre of collecting area. The €650 million (about US$690 million) funding for phase 1 will only deliver four-tenths of that. Nevertheless, it should have the sensitivity to detect primordial galaxies across large patches of sky.

    9

    The first phase of SKA-low will churn out raw data at a daily rate greater than the world’s internet traffic; impossible to store, or for human minds to process in real time. Ingenious algorithms will be needed to sift valuable nuggets from the deluge.

    The University of Cambridge leads a consortium of 23 organisations, including Perth’s ICRAR, to develop new hardware and software systems for the task. One of ICRAR’s major software contributions goes by the name DALiuGE – an acronym for “data activated logical graph engine”. It’s also a bilingual play on the word deluge: “liu” is a Chinese character meaning “flow”.

    Last June, an ICRAR team successfully ran the prototype of DALiuGE on the second-most powerful supercomputer in the world, Tianhe-2, in Guangzhou, China. Next, the team hopes to test it on the most powerful, Sunway TaihuLight in Wuxi, eastern China.

    The computing challenges may be huge, but it’s not the first time the global community has taken on something so big. To solve CERN’s problem of distributed processing and information sharing, its researchers ended up developing the World Wide Web. “That changed our world forever,” Quinn says. “I suspect the SKA will do the same.”

    SKA’s rewards are already reaching beyond science into industry. Besides CISCO and IBM, other big-name collaborators on the project include British-Australian mining giant Rio Tinto, international gas and oil company Chevron, Amazon and Intel. All are highly attuned to new ways of solving their big data problems – whether it is crunching data to make images of oil, gas and mineral deposits below the ground, or finding patterns in vast databases.

    Construction in the middle of nowhere

    The computational challenges of the SKA are formidable; so too are those involved in building and rolling out the infrastructure in the middle of the Australian outback. It’s a perfect job for a former army tank officer.

    Tom Booler has been project manager for the MWA and part of the SKA-low team since 2011. His mission is to plan the construction and deployment of 130,000 antennas in the desert – absent a local workforce, with no construction equipment and no power grid. And that’s only the first phase of SKA-low. The second, slated for the mid-2020s pending funding, will see the number of antennas swell to about a million. The scale, cost and remoteness of the site make it one of the toughest science projects ever undertaken.

    Supplying power is a major hurdle. The MWA is powered by a 1.6 MW hybrid solar-diesel power station, parts of which must be shielded to stop the radio waves it creates from interfering with the telescope. Phase 1 of SKA-low will need 2.25 MW. Phase 2 will need the power supply of a small city.

    Extreme weather also has to be factored in. In 2015, nearby Milly Milly Station bore a year’s worth of rain in five months. While cattle grazers welcomed it, road closures disrupted plans at the observatory. Besides sudden downpours, Booler also has to reckon with temperatures soaring over 40 ºC in the summer months – and then there’s the desert death adder.

    But one thing the shire of Murchison has going for it – and a reason it won the bid for the SKA – is the quiet. Population density is extremely low – just 115 people spread over an area the size of the Netherlands. There are no mobile phone towers or radio and television transmitters. The shire is also hushed by regulations enforced by the Australian Communications and Media Authority.

    Within the observatory, every appliance gets stripped of wi-fi hardware before it arrives. The observatory control centre, which houses computers that crunch data from the existing telescopes, is the radio equivalent of an airlock, with radio-wave-proof double doors and no windows.

    Inside a radius of 70km around the observatory authorities can order mobile phones be turned off. Out to 260km emissions are regulated in key radio frequency ranges.

    The entire area is more than six times bigger than the US National Radio Quiet Zone, home to the Green Bank radio telescope and a population running into hundreds of thousands.

    The quiet zones do not extend to high altitudes, so planes communicating with air traffic control could present a problem. To tackle that issue, CSIRO researchers have begun to investigate ways to measure the interference and remove it from the telescope observations.

    Final stretch

    As difficult as building the SKA will be, coming up with the money to bankroll it is trickier. Negotiations with the 10 participating governments for the first phase have been underway since late 2015.

    But there’s a new sense of ease pervading the SKA community as it looks to an April 2017 sign-off on a binding treaty known as an International Government Organisation (IGO).

    Once signed, ministers of each country will have a year to ratify it. Once ratified, researchers are confident things should roll out smoothly. There is a strong precedent: CERN is governed by an IGO, with 22 member states. “It’s a well-tested model,” says Pearce, who previously worked on computing challenges for the LHC as part of a multinational collaboration.

    With SKA-low expected to come online in 2021, and be fully operational in 2024 astronomers are at last allowing themselves to get excited. “Until we can put a radio telescope on the moon, it will be the greatest advance in low-frequency radio astronomy,” says Elisabeth Mills, a radio astronomer at San José State University in California. “With such a great leap in technical capabilities, the most important advances from this telescope may be in areas we cannot even currently predict or imagine.”

    Back to the cosmic dawn

    We know something of the first few moments after the violent birth of our universe. A split second after the Big Bang, it was a tiny mushrooming fireball, 10 billion degrees hot and filled with a plasma of frenetic charged particles.

    Over the next 380,000 years, the expanding universe cooled. Charged particles – electrons and protons – lost enough of their youthful energy to bond with each other and form the first hydrogen atoms. In this more staid universe, light from the Big Bang could at last move in uninterrupted straight lines. As space continued to expand, the light waves stretched to the length of microwaves – which we see today as the cosmic microwave background.

    This much we know. The next episode remains a mystery.

    At 380,000 years old, the universe was a peaceful sea of hydrogen. A billion years later, most of it was gone. We know a small percentage snowballed under the influence of gravity to form stars and galaxies. But the vast intergalactic sea of hydrogen gas disappeared, reionised into a plasma of protons and electrons. The era is known as “the epoch of reionisation”.

    How did this happen? It turns out there are lots of theories, and they are almost completely unconstrained by data.

    Traces of dark matter laid down in the Big Bang, slightly denser than their surrounds, may have triggered the snowballing of hydrogen into stars. But why did the intergalactic hydrogen disappear?

    The leading theory is ultraviolet radiation from the first hot stars stripped the surrounding hydrogen of its electrons. But there is another contender: quasars. Quasars (quasi-stellar radio sources) are among the brightest and oldest objects in the universe. They are powered by black holes; the source of their light is the radiation emitted by accelerating gases as they are sucked towards the accretion disc. Quasars can be surprisingly ancient, appearing just 770 million years after the Big Bang.

    “It’s controversial, but one exciting possibility is that it was quasars that reionised the universe,” says astrophysicist Stuart Wyithe, at the University of Melbourne, who specialises in trying to recreate this unknown period of the history of the universe. The theory also suggests that massive black holes may have played a far greater role in shaping our Universe than previously thought.

    In Wyithe’s computer modelling, the ancient universe resembles Swiss cheese. The cheese is neutral hydrogen and the holes are where it has been eaten away, leaving an ionised plasma. Over a period of about 300 million years, the holes grow larger until, by about a billion years after the Big Bang, there’s almost no cheese left.

    SKA-low is designed to supply theorists like Wyithe with hard data. It will have the resolution and the wide angle to map the distribution of hydrogen in the early universe and trace how it changed over time. He will combine these images with those from the Hubble telescope to try and detect what’s at the centre of those cheesy holes: stars or quasars.

    See the full article here .

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  • richardmitnick 2:44 pm on February 25, 2017 Permalink | Reply
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    From CSIRO via AFR: “The Square Kilometre Array: going to infinity and beyond” 

    CSIRO bloc

    Commonwealth Scientific and Industrial Research Organisation

    2

    The Australian Financial Review

    Feb 24 2017
    Tess Ingram

    1
    In the red dust of WA, telescopes are already tuning in to the faint signals from the very edge of the universe. TREVOR COLLENS

    Thunderstorms are common in the Murchison region of Western Australia in January but for Luke Horsley the 21 millimetres of rain that drilled into the red dirt overnight are problematic.

    It is 6am in an old stone cottage at Boolardy Station. Horsley grabs the receiver of a black landline telephone and tells a colleague 330 kilometres away in Geraldton not to make the bumpy four-hour drive from the coast. The roads might be closed.

    The landline, which would look commonplace in any city office, stands out at Boolardy. Horsley may be working as an engineering support technician at a $400 million high-tech facility but using a mobile phone or even a humble Wi-Fi network is not an option. The radio waves they produce would obliterate the science he is working on – radio astronomy.

    Horsley and his colleagues are here in the middle of nowhere working on the world’s largest science project – the Square Kilometre Array (SKA).

    SKA Square Kilometer Array

    A multibillion-dollar endeavour first dreamt up in 1991, the SKA is in essence a vast radio telescope that will literally look back through time to the dawn of the universe. To call its mission ambitious is to redefine understatement – the SKA aims to resolve some of the most profound unanswered questions of our time. Was Einstein right about gravity? When did the first stars, galaxies and black holes form? What is dark energy? And, quite possibly, are we alone in the universe?

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    A racehorse goanna explores one of the tiles in the Murchison Widefield Array. Trevor Collens

    To achieve this ten countries have joined forces to build the SKA – a telescope so large it will eventually have a collecting area of more than a million square metres. Australia won the right to host part of the project in 2012 after a hotly contested 8-year bidding process conducted by the SKA Organisation, the not-for profit dedicated to overseeing its design, construction and operation.

    South Africa will share the prize, ultimately hosting 2000 dishes probing the universe as far as six billion light years away. And here in the red dust of the Murchison a million individual antennas, each resembling a Christmas tree, will eventually tune in to the faint signals from the very edge of the universe – “light” emitted by events more than 13 billion years ago.

    SKA Murchison Widefield Array,SKA Murchison Widefield Array, Boolardy station in outback Western Australia, at the Murchison Radio-astronomy Observatory (MRO)
    SKA Murchison Widefield Array,SKA Murchison Widefield Array, Boolardy station in outback Western Australia, at the Murchison Radio-astronomy Observatory (MRO)

    Before the storm

    It is the day before the thunderstorm and here in the low-lying mulga scrub even the racehorse goanna look like they’re over the 38-degree temperatures and enervating humidity. Until a few years ago Boolardy was a cattle station and my visit coincides with that of the former manager and his daughter, here to round up the last escapee livestock.

    The Murchison shire, which is roughly the size of Denmark, is an ideal site for radio telescopes. It is so isolated it describes itself as “the shire with no town” – and claims to be the only one in Australia. During the SKA bidding process the Australian government protected it with a 260-kilometre “radio quiet zone”. Given the 50,000-square-kilometre area is home to just 113 people – most in the local Pia Wadjarri Indigenous community as well as a few remaining station owners – the chances of unwanted radio activity are slim.

    4
    Dr Balthasar Indermühle and Brett Hiscock in front of some of CSIRO’s 36 ASKAP radio telescope dishes in the Murchison scrub. TREVOR COLLENS

    Still, visitors aren’t encouraged. An “emergency flipchart” on the wall of a site office has instructions for dealing with an “unaccounted visitor” alongside “fire and explosions” and a “bomb threat response”. Disrupt the science at your peril.

    In the airvconditioned comfort of a control building buffered by two double-door “airlocks”, CSIRO experimental scientist Dr Balthasar Indermühle is working on a radio-frequency interference (RFI) monitoring system he is building. The Swiss-born scientist is here from his home in Sydney and his job is to keep the two radio telescopes that currently occupy the Murchison Radio-astronomy Observatory (MRO) as clean of radio interference as possible.

    Indermühle was an airline pilot in Switzerland. Flying through the sky at night is about as close as you can get to space travel without leaving the planet and from his vantage point in the cockpit, he would regularly contemplate the universe. After exchanging airplanes for software development and founding a company called Inside Systems, Indermühle was drawn back to the night sky. Having already tinkered away at a Masters in astronomy online, he left for Australia to undertake a PhD in astrophysics at the University of New South Wales.

    Indermühle’s main interest lies in making this pursuit as easy as possible by minimising the amount of “earth noise” the radio telescopes pick up. This is no easy feat. To detect such weak radio signals from space, the telescopes need to be ultra-sensitive.

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    The MRO is at the centre of a 500km wide radio quiet zone where no mobile phones are allowed. TREVOR COLLENS

    “The entire energy that has been received by all the radio telescopes on the planet since the beginning of radio astronomy, the energy equivalent of that is ash from a cigarette dropping one centimetre in height,” Dr Indermühle explains as we circle one of the dishes hard at work.

    “That is how sensitive our equipment is. We could see a mobile phone that is a light year away.” A mobile phone on the moon heard via these telescopes would be booming, let alone one at Boolardy.

    Indermühle is one of a small crew of engineers and scientists, from the CSIRO and The International Centre for Radio Astronomy Research (ICRAR), who are pushing the frontiers of astronomical science at the MRO, which will host the SKA and is already home to the MWA and ASKAP telescopes.

    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia
    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia

    Horsley, his ICRAR colleague Mia Walker and Dutch intern Ric Budē are braving the heat at the MWA to undertake repairs and prepare for the rollout of an expansion. The remainder of their team, former firefighter Dave Emrich and intern Kim Steele, who was part of a “student army” that helped build the array and is now working on the project full time, are in the MRO’s control building working on the spaghetti strands of cables that feed the data from the MWA into a complex computing system. Steele’s own journey is about to take a new turn when she jets off to Finland to undertake her PhD.

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    Former firefighter Dave Emrich says “when you look up at the sky at night and see all the stars; it makes you think”. Trevor Collens

    Everywhere else is dead quiet.

    Dark stuff

    If a mechanic told you he only understood about 5 per cent of your car, you wouldn’t be filled with confidence. Unfortunately, this is the awkward situation astronomers are in.

    “Astronomers are incredibly ignorant of the universe we live in,” explains ICRAR executive director Peter Quinn, an astrophysicist who once worked on the Hubble Telescope with NASA. “There’s about 95 per cent or more of it that’s been called ‘dark’.” Roughly 25 per cent of that is considered dark matter and 70 per cent dark energy. Scientists have little idea what they are.

    Quinn heads up ICRAR in Perth, a research facility set up specifically to help interpret data from the Murchison telescopes and run jointly by Curtin University and the University of Western Australia. It is part-funded by the WA government. Like so many of the others I meet while researching the SKA, Quinn’s journey into the deep space world has – much like the project itself – had unlikely stops and starts but never been short of interesting.

    Quinn began at the University of Wollongong and moved on to the prestigious California Institute of Technology before joining the Hubble institute at NASA’s Space Telescope Science Institute in Baltimore. He returned to Australian National University to lead a global search for dark matter. His work did indeed find early evidence of dark matter and in 1991 graced the cover of Nature. From there Quinn went to the European Southern Observatory headquarters in Munich and ultimately to ICRAR. He has spent the bulk of this career trying to crack the “dark” mystery.

    “I wanted to understand why all these galaxies looked like they looked,” Quinn tells me. “Why are some round and some flat and some green and some blue? When you start down that path, you all of a sudden realise what you’re looking at is just the frosting on the cake.

    “What the universe really made is all this black stuff which sits underneath. This dark stuff is driving everything, its presence, its shape, its physics. If you want to understand galaxies, you have to understand this dark stuff.

    “That’s probably the biggest, in my mind, unsolved mystery in the universe.”

    He is hopeful the SKA might provide an end to the “frustrating search” during his lifetime. Resolving this mystery is one of the five core science drivers of the project.

    A movie of the deep past

    7
    Murchison Widefield Array Project Manager Randall Wayth switched from computers to space. TREVOR COLLENS

    After the Big Bang, which is thought to have occurred about 13.7 billion years ago, the universe was transformed from an expanding ball of hot particles into a cool sea of gas, predominantly hydrogen. This is thought to have occurred over about 380,000 years.

    Inflation to gravitational waves derived from ESA/Planck and the DOE NASA NSF interagency task force on CMB research, Bock et al. (2006, astro-ph/0604101); modifications by E. Siegel.
    Inflation to gravitational waves derived from ESA/Planck and the DOE NASA NSF interagency task force on CMB research, Bock et al.

    There was no light during this time, aptly known as the Dark Ages, so no optical telescope has ever been able to observe this phase of the universe’s evolution.

    At some point – probably about 400 million years after the Big Bang – there was the “cosmic dawn” when the first galaxies and stars are thought to have burst into existence.

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    Cosmic dawn. BBC

    But it took until about 1 billion years after the Big Bang for radiation from those stars and galaxies to clear the hydrogen “fog” and allow light to escape. That period of about 600 million years is known as the “Epoch of Reionisation” and it is one of the last frontiers in cosmology.

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    Epoch of Reionisation

    The MWA telescope is already working to define what happened.

    Trick of the light

    It may sound impossible to delineate something so massive but it works like this.

    Human eyes can only collect and focus a certain range of the electromagnetic spectrum – what we call visible light. But in order to understand the universe, we need to study astronomical objects over the broad range of wavelengths they emit – from the gamma rays emitted from emerging stars to the radio waves released from black holes.

    Radio waves are simply “invisible” light and astronomers have developed telescopes to pick up this light in wavelengths ranging from a fraction of a millimetre to metres long. The more sensitive the telescope, the clearer picture it can create of weaker signals. The older the signal, the weaker it is because it has stretched out as it has travelled – just like when you look at the sun, you are seeing it as it was 8.2 minutes ago because that is how long it takes sunlight to travel to Earth.

    Therefore, the most powerful radio telescopes are essentially time machines.

    FAST radio telescope located in the Dawodang depression in Pingtang county Guizhou Province, South China
    FAST radio telescope located in the Dawodang depression in Pingtang county Guizhou Province, South China, the world’s most powerful radio telescope

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres
    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres, cureently the world’s most productive installation for millimeter and submillimeter astronomy

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    Dr Balthasar Indermühle’s main interest lies in minimising the amount of “earth noise” the radio telescopes pick up. Trevor Collens

    Time travel

    For scientists like MWA director Randall Wayth, time travel comes with its challenges.

    Wayth, a software consultant who followed his passion to become an astrophysicist, says the Epoch of Reionisation project is the most challenging project the telescope is seeking to complete.

    “It is really difficult because the signal we are looking for is about a million times fainter than all of the other stuff that’s in the sky,” he says.”This is like looking for a little torch next to a really big spotlight.”

    Wayth spent five years in software consulting before deciding to opt for “something a bit more meaningful” – a phD in astrophysics at the University of Melbourne. “It turns out that the whole radio astronomy side of things is an astonishingly good use of everything that you learnt in your engineering degree,” Wayth says. “And with modern radio astronomy as well it’s everything you learnt in your computer science degree because it’s all computers. No one actually goes and looks through an eyepiece anymore.”

    He returns to the Epoch of Reionisation.

    “We know about the very early universe. We know about today and halfway back in time,” he says. “Then there is this period that we almost know nothing about. That is what we’re trying to get to with the Epoch of Reionisation experiment.”

    At first glance the 2048 squat, spider-like antennas that constitute the MWA radio telescope are not at all impressive. But it is the MWA that has the honour of reaching back to the cosmic dawn and directly informing the design of the SKA’s future low-frequency antennas, which will be much more powerful. The MWA receives signals within the 80 to 300 megahertz bandwidth, the same low frequencies we typically broadcast FM radio and television signals on. It has been surveying the southern hemisphere since 2013.

    “The MWA would detect the Epoch of Reionisation and see things within it, but then the SKA would come along and see it in much greater resolution,” says Wayth.

    “We’re not sensitive enough to directly make images, which is kind of the holy grail, but SKA will be able to do that. What we can do is say, ‘yes, it happened over this time range and the kind of objects that are involved must have been X-ray emitting objects or small galaxies’ or whatever it was. So, we’ll be able to tie it down to some space and then SKA can go in.”

    So what has the MWA found in it’s three years of searching the southern skies? A big part of the answer is its GaLactic and Extragalactic All-sky MWA (GLEAM) survey. GLEAM produced a catalogue of 300,000 galaxies, picking up radio waves which, when translated into images, showed the sky in 20 primary colours – far better than the three humans can manage. With these images astronomers are already planning where to zoom in on when SKA comes online next year.

    Wayth and Emrich have similar backgrounds. Both studied electrical engineering, with Emrich tacking on computer systems and Wayth computer science. After years as a professional engineer and then bush firefighter, an opportunity came up for Emrich to apply his background to a persistent passion of his, astronomy.

    He can trace his fascination with space back to his grandparents who took him camping in Hyden, a small town about 300 kilometres south-east of Perth popular with tourists because of its large wave-shaped rock, when he was a child.

    “They used to take us out to Wave Rock and Hyden and things to look at the sky at night,” Emrich recalls. “I remember gramps rattling the tent at 3am when we were all asleep and saying ‘you have to have a look at this’ and all of us grumbling about how early it was.

    “I think there is something primitive about human beings that when you look up at the sky at night and see all the stars; it makes you think.”

    He has been involved in the MWA project since 2009 and says he has lost count of how many times he has travelled to the Murchison observatory, probably close to 100. His wife and three teenage children – who live in Perth – don’t mind the time away as much as they did when he was battling bushfires across Western Australia – at least these trips are planned in advance.

    8
    A “radio colour” view of the sky above a tile of the Murchison Widefield Array radio telescope.The Milky Way is visible as a band across the sky and the dots beyond are some of the 300,000 galaxies observed by the telescope for the GLEAM survey. Credit: Radio image by Natasha Hurley-Walker (ICRAR/Curtin) and the GLEAM Team. MWA tile and landscape by Dr John Goldsmith / Celestial Visions. Curtin/ICRAR/JohnGoldsmith

    Kelly’s input

    Patricia Kelly is as responsible as anyone for Australia being chosen to co-host the SKA. A career public servant whose early work included developing social policy, Kelly’s journey took a turn towards science when she she moved to the Industry department in 1995 and began working with the research sector and on innovation policy. In 2007 she became involved with the SKA bidding process through her role as deputy secretary responsible for the department’s science and research streams.

    As the big idea crystallised into action Kelly led a joint bid by Australia and New Zealand to host the entire project. She was in Amsterdam advocating Australia’s case in 2012 when the SKA Organisation decided to split the project between Australia and South Africa. There was, Kelly says, an element of politics in that call. “But I think in the end it has not been a bad outcome. It has made it a truly global project in a way I think it wouldn’t have been if it had gone one way or the other.”

    Today Kelly chairs the Australia-New Zealand SKA Co-ordination Committee (NZ remains involved despite missing out on hosting the science) and is Australia’s representative on the board of the international SKA Organisation, which includes members from Australia, Canada, China, India, Italy, New Zealand, South Africa, Sweden, the Netherlands and the United Kingdom and is co-ordinating the whole project.

    There’s a lot to do.

    Two-phase approach

    The SKA is to be constructed in two phases. The first phase, SKA1, will constitute about 10 per cent of the full array and is about three-quarters of the way through its final design phase.

    SKA1 will see about 200 dishes rolled out in South Africa’s Karoo, a lightly populated semi-desert region north of Cape Town, including 64 dishes known as “MeerKAT” that have been acting as a local precursor project. The dishes will cover the 350MHz to 14 gigahertz range of the spectrum.

    SKA South Africa Icon
    SKA South Africa

    9
    Solar panels will provide power for the Murchison Radio-astronomy Observatory. Until now it has relied on diesel-powered generators. Trevor Collens

    In Australia, about 130,000 low frequency antennas will be constructed to cover the 50 to 350MHz range. Although the MWA’s “spiders” have been informing their design, the SKA antennas more closely resemble Christmas trees. The cost of constructing SKA1 has been capped at €675 million, with operations expected to cost another €100 million a year.

    Phase two will see the collective array expand to more than its namesake square kilometre, with a total 2000 dishes in South Africa and other African countries, including Botswana, Ghana and Kenya, and a staggering one million Christmas tree antennas creating a forest above the Murchison scrub.

    It is undoubtedly a huge endeavour with a significant cost. But everyone AFR Weekend speaks with is confident there will be payoffs beyond understanding what happened a long time ago in a galaxy far, far away.

    Wi-Fi was the result of CSIRO radio astronomers seeking to detect tiny, exploding black holes. A scientist at CERN, the European Organisation for Nuclear Research, invented the World Wide Web in 1989 to meet the demand for information sharing between scientists. Hierarchical Segmentation software developed by NASA is now used in medical imaging. Surely the SKA will be no different.

    Kelly, who is also the director-general of IP Australia, says it is most likely the SKA’s spin-offs will be things we are not able to predict.

    “Certainly the amount of data the telescope will generate and how to handle that data will be something that will generate a great deal of information and learning,” Kelly says.

    “The technologies being developed in terms of sensors … will have much broader implication for a range of industries and there is also a real need for ways of powering this telescope in an affordable way, so there is also a lot of work being done on remote energy solutions that, of course, are very much in the national mix at the moment.”

    Hitting top gear

    10
    There are 36 ASKAP dishes dotted across the MRO. Designed and built by the CSIRO, the organisation hopes the pioneering technology will be used by the larger SKA array in South Africa. Trevor Collens

    January has been an exciting month for the CSIRO’s Antony Schinckel. The man responsible for the design, construction and commissioning of the $165 million ASKAP telescope has just seen it click into top gear after extensive testing. And already the results, and the way they are being processed, is encouraging.

    ASKAP, Australian Square Kilometre Array Pathfinder, is the more familiar looking telescope at Murchison. It consists of 36 large, white dish antennas that work together as a single instrument. Each one bears a local Wajarri name – including Bundarra (stars), Wilara (the Moon) and Jirdilungu (the Milky Way) – an honour also afforded to Schinckel himself.

    “My Wajarri name is Minga, which is the Wajarri word for ant,” he explains from his office in Sydney. “I am certainly quite honoured to be one of the few people that was given a name.”

    The ASKAP telescope is mapping space out to about 3 billion light years away, using neutral gas to reveal hundreds of thousands of galaxies. The project, expected to take five years, is creating mind-boggling amounts of data. Even operating well below its full capacity the antennas are now churning out 5.2 terabytes of data per second. That’s about 15 per cent of all the data bouncing around the internet on any given second.

    From the telescope, the data goes down an 800km fibre optic cable to the Pawsey Supercomputing Centre and into a new, near automatic data-processing system Schinckel and his team have developed.

    “It’s like a 24/7 prestige car manufacturing plant – the raw materials flow in at one end, you decide what type of car you want to roll off the production line, and therefore what parts you need, and let it go to work overnight. Next morning you get a brand new, never been seen before, high-performance car.”

    While the ASKAP will not be directly used in Australia’s end of the SKA (that job’s for the “Christmas trees”), it as an important demonstrator of a key technology the CSIRO has designed and is being considered for the SKA mid-range telescopes to be rolled out in South Africa.

    Called a phased array feed (PAF), the technology is essentially an advanced version of a traditional radio telescope receiver, which detects and amplifies radio waves. Traditionally receivers have only been able to take snapshots of small pieces of the sky at once but the PAFs, with 188 individual receivers positioned in a chequerboard, allow a dramatically wider field of view.

    Schinckel, who spent 17 years at high-profile observatories in Hawaii, says the CSIRO has already sold one PAF to the Max Planck Institute for Radio Astronomy in Germany and is building a second for the Jodrell Bank Observatory in England. The next step could be its use in other fields.

    “In many ways we don’t know enough to know what those other uses might be,” Schinckel says.

    “They might be in medical imaging, for example, in tomography. It might be in ground imaging from aeroplanes or satellites. It could be in communications in cities where you have extremely high density communications and there are limits that that imposes. We simply don’t know at this juncture.

    “When you typically look back about five or ten years after a telescope was built, and you look to see what was the really exciting science that came out of it, often only about 30 per cent of the science that’s come out of it was what you had predicted or planned right back at the start,” he says.

    The big challenge

    Making sure the SKA has the computing power and data processing systems to handle the deluge of data is the big challenge for ICRAR’s director of data intensive astronomy, Andreas Wicenec.

    Phase one of the SKA alone will produce five times 2015’s global internet traffic. The data collected in a single day would take nearly two million years to play back on an iPod and will require the power of computer processing systems around ten times the size of today’s biggest machines.

    “This is a very important part of the project because this is the limiting factor essentially,” ICRAR’s Quinn says. “Unless they can manage the data, then the telescope doesn’t work.”

    The challenge of ensuring the SKA can process this unprecedented volume of data in near real-time is being tackled by institutes and companies across the globe, including tech powerhouses Amazon, Intel, IBM and Cisco Systems which are all providing input into how the systems should function.

    The brain – data flow

    From Perth, Wicenec is sharing valuable insights with the SKA design teams from the data journey of the spidery-MWA. He is also taking a leading role in designing the “brain” of the SKA – the science data processor.

    After a correlator on site at the MRO has conducted a first filter of the mass of data, reducing it in size, it will travel down the fibre optic cable to Perth’s Pawsey Supercomputing Centre.

    12
    SKA correlator

    Here the “brain” extracts unwanted radio noise, from an errant mobile phone or the odd aircraft that flies overhead, and turns the data into something scientists can use, such as an image which can then be distributed to scientists across the globe,

    In terms of data flow, the MWA is a factor of 20 larger than the last project Wicenec worked on, the Atacama Large Millimeter Array in Chile, an ambitious array perched atop a plateau more than 5000 metres above sea level.

    “That’s already a big step but what we are talking from MWA to SKA is actually a factor of 1800 in terms of data flow,” Wicenec says, explaining the SKA’s jump in scale also delivers an increase in resolution, compounding the data deluge.

    And if that wasn’t hard enough, scientists from across the globe, ranging from the Onsala Space Observatory in Sweden to the National Centre for Radio Astrophysics of India, need the data to be sent out again.

    “We are actually sending about three to four times more data out [from the MWA] than what we are receiving, so that means about a good gigabyte or 1.2 gigabytes a second out to people every single day,” Wicenec says.

    Managing the project

    If you think managing tradies on your home renovation is tough, spare a thought for David Luchetti. As general manager of the Australian SKA Office, he heads the agency responsible for co-ordinating Australia’s commitment to the project – everything from federal funding to site access – and has unrivalled knowledge on its progress. For a public sector veteran who took on the role with little understanding of astronomy, building knowledge of the science has been a learning curve.

    “Even now, after my eight years [in the role], it makes you realise that there’s some seriously smart people out there,” Luchetti laughs. “There’s been a certain process of osmosis, I think, in actually absorbing some of the collective wisdom of the people.”

    He says the biggest challenge in a role co-ordinating a highly complex, multibillion-dollar project has been to keep momentum going on its many and varied streams of work. There’s finalising the design, securing funding, signing the Indigenous Land Use agreement and liaising with the WA government.

    “It’s not a sequential project, in the sense that once you do ‘A’ then you move on to ‘B’,” he says. “Keeping all of them moving at the same time is probably the main challenge.”

    Luchetti says the global effort is like a duck, “it’s quite serene on top but there is a lot happening below the surface”. He has also been responsible for translating “scientist” into “politician”. A key hurdle for sciences such as astronomy is to translate researchers’ excitement about the unknown into funding. The idea of “we will find something or there will be a spin-off but we can’t tell you what it will be” does not sell easily.

    The Australian government has understood the vision, contributing about $400 million to SKA-related activities to date, with the West Australian government spending about a further $111 million on radio astronomy, most linked to the SKA. Premier Colin Barnett says the SKA could add more than $100 million to the state’s economy over the next 20 years through locally supplied goods and services. And managing all those terabytes of data would bring valuable experience to WA.

    Alien life

    But what about the aliens? The first thing that comes to many peoples’ minds when they think about what else could be out there is aliens. Is there other intelligent life? SKA could provide an answer.

    The man heading the entire SKA project, Phil Diamond, director general of the SKA Organisation.

    “The public think that [looking for aliens] is what we do,” Diamond says. “It is not actually what radio astronomers do. However, SKA will be the most capable machine that human kind has ever developed to hunt for that signal from intelligent extraterrestrial civilisations.

    “We do have people within our science working groups who are focused purely on that aspect but it is definitely not the main stream of what we do.

    “However if we detect the signal, I think the interest will rise enormously.”

    Enormously is an understatement. If an artificial signal which suggests intelligent life, for example a distant airport, is detected by the SKA, another radio telescope would be used to verify the signal. And then, Diamond explains there is actually an astronomical protocol for how it should be dealt with.

    “There is no way it could remain secret because with the prevalence of social media these days, it gets out,” he says. “It would be global news within 24 hours.”

    For Diamond, a 35-year radio astronomer, his key interest is not in the extraterrestrial but rather how our own galaxy has evolved.

    “I am quite interested in the theme we have dubbed ‘the cradle of life’ which will look at how planets form and evolve, detecting the molecular signals of amino acids and things like that in space,” he says.

    Two key focuses

    But before the science, Diamond has a big job on his hands.

    “We are dealing with more than 600 scientists and engineers in more than 10 countries… people in almost every time zone you can imagine from New Zealand to Western Canada and all the cultural and language differences that go with that,” Diamond says.

    “Pulling all of that together has been one of the biggest challenges. I do say to my staff here that the communications in this project will be perfect the day we switch the telescope off,” which is expected to be about 50 years after it fires up.

    The SKA Organisation has two key focuses at the moment – signing off on a final design and inking a binding SKA treaty between the 10 member countries, committing them to funding and contracts for the commencement of construction, targeted for late-2018.

    But even Diamond admits hitting that construction target will be a tough ask.

    “That is going to be very tight,” he says. “There are multiple things that have to happen before we can start construction. On the design side we have to deliver a design that has been validated and is ready to go out to industry for tender. On the other side the governments have to deliver a convention, the governance structure and the legal organisation that enables us to receive money from the governments and go out and pay industry.

    “These things have to converge on the right time scale. So far everything is pointing in the direction that will happen … but it is very tight.”

    Diamond can control the design process but the speed of the governments is out of his hands. For example, all of the Brexit legislation that has to go through the British government could slow the nation ratifying its end of the treaty.

    As it reaches the end of the design process, the SKA Organisation is also re-examining its €675 million cost target for the construction of SKA1.

    “Like all major scientific projects like this, our cost estimates are coming in a little higher than we had hoped,” Diamond says. About 30 per cent to be exact.

    “So we are looking at if there is any reuse of technologies and software from the precursors that can help us reduce the costs. This is a normal project process, it is nothing out of the ordinary.”

    While all of that is a long way from the MWA team assembling more spidery antennas in the scorching heat of the Murchison, there is a palpable excitement that their telescope could now play an even bigger role in the world’s largest science project.

    As they make the 40km drive back to Boolardy from the MRO, lightning flashes overhead. Everyone is praying the storm doesn’t target its science – last year it claimed thousands of dollars worth of antennas atop CSIRO’s radio interference tower.

    The night passes and while the lightning has not been an issue, the rain has. Horsley was right to be worried, all but one of the roads has been closed. And the forecast for tomorrow is no better.

    The ICRAR team cuts their site trip three days short and piles into the back of rented four-wheel drives, dodging lizards and kangaroos on their way back to Geraldton.

    The radio waves are from 13 billion years ago, they can wait another month.

    The reporter travelled to the MRO courtesy of ICRAR.

    See the full article here .

    Please help promote STEM in your local schools.

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

     
    • richardmitnick 10:59 pm on February 25, 2017 Permalink | Reply

      The sciencesprings blog is shown on Twitter. The Twitter feed for this post resulted in 63 retweets.
      I am thrilled.

      Like

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