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  • richardmitnick 8:34 am on March 7, 2017 Permalink | Reply
    Tags: , , , ICRAR, Star clusters discovery could upset the astronomical applecart, Star clusters in the Large Magellanic Cloud   

    From ICRAR: “Star clusters discovery could upset the astronomical applecart” 

    ICRAR Logo
    International Centre for Radio Astronomy Research

    March 7, 2017
    Dr Bi-Qing For (ICRAR-UWA)
    biqing.for@icrar.org
    +61 8 6488 7729

    Dr Kenji Bekki (ICRAR-UWA)
    kenji.bekki@icrar.org
    +61 8 6488 7730

    Pete Wheeler—Media Contact, ICRAR
    pete.wheeler@icrar.org
    +61 423 982 018

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    This image from NASA’s Spitzer Space Telescope features the Large Magellanic Cloud, a satellite galaxy to our own Milky Way galaxy. Overlaying the image are circles showing the locations of 15 star clusters where multiple generations of stars have been discovered. Credit: Karl Gordon and Margaret Meixner – Space Telescope Science Institute/AURA/NASA. Compilation by Bi-Qing For and Kenji Bekki (ICRAR/UWA).

    The discovery of young stars in old star clusters could send scientists back to the drawing board for one of the Universe’s most common objects.

    Dr Bi-Qing For, from the International Centre for Radio Astronomy Research in Perth, said our understanding of how stars evolve is a cornerstone of astronomical science.

    “There are a billion trillion stars in the Universe and we’ve been observing and classifying those we can see for more than a century,” she said.

    “Our models of stellar evolution are based on the assumption that stars within star clusters formed from the same material at roughly the same time.”

    A star cluster is a group of stars that share a common origin and are held together by gravity for some length of time.

    Because star clusters are assumed to contain stars of similar age and composition researchers have used them as an “astronomical laboratory” to understand how mass affects the evolution of stars.

    “If this assumption turns out to be incorrect, as our findings suggest, then these important models will need to be revisited and revised,” Dr For said.

    The discovery, published today in the Monthly Notices of the Royal Astronomical Society, involves a study of star clusters located in the Large Magellanic Cloud, a neighbouring galaxy to the Milky Way.

    By cross-matching the locations of several thousand young stars with the locations of stellar clusters, the researchers found 15 stellar candidates that were much younger than other stars within the same cluster.

    “The formation of these younger stars could have been fuelled by gas entering the clusters from interstellar space,” said co-author Dr Kenji Bekki, also from the International Centre for Radio Astronomy Research.

    “But we eliminated this possibility using observations made by radio telescopes to show that there was no correlation between interstellar hydrogen gas and the location of the clusters we were studying.

    “We believe the younger stars have actually been created out of the matter ejected from older stars as they die, which would mean we have discovered multiple generations of stars belonging to the same cluster.”

    Dr Bekki said the stars were currently too faint to see using optical telescopes because of the dust that surrounds them.

    “They have been observed using infrared wavelengths by orbiting space telescopes Spitzer and Herschel, operated by NASA and the European Space Agency,” he said.

    “An envelope of gas and dust surrounds these young stars but as they become more massive and this shroud blows away, they will become visible at optical wavelengths for powerful instruments like the Hubble Space Telescope.”

    “If we point Hubble at the clusters we’ve been studying, we should be able to see both young and old stars and confirm once and for all that star clusters can contain several generations of stars.”

    See the full article here .

    Please help promote STEM in your local schools.
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    Stem Education Coalition

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

    ICRAR is:

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

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

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

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

     
  • richardmitnick 2:44 pm on February 25, 2017 Permalink | Reply
    Tags: , , , ICRAR, , , , SKA South Africa   

    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

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    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.

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    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.

    6
    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

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    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.

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    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

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    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

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    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.

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    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.

    STEM Icon

    Stem Education Coalition

    CSIRO campus

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

     
    • richardmitnick 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

  • richardmitnick 3:11 pm on January 18, 2017 Permalink | Reply
    Tags: , , , , , Galaxy Murder Mystery, ICRAR,   

    From ICRAR: “Galaxy Murder Mystery” 

    ICRAR Logo
    International Centre for Radio Astronomy Research

    January 17, 2017
    Mr Toby Brown (ICRAR-UWA, Swinburne University of Technology)
    E: toby.brown@icrar.org
    M: +61 6488 7753

    Dr Barbara Catinella (ICRAR-UWA)
    E: barbara.catinella@icrar.org
    Tel: +972 89346511

    Pete Wheeler—Media Contact, ICRAR
    E: pete.wheeler@icrar.org
    M: +61 423 982 018

    1
    This artist’s impression shows the spiral galaxy NGC 4921 based on observations made by the Hubble Space Telescope. Credit: ICRAR, NASA, ESA, the Hubble Heritage Team (STScI/AURA)

    It’s the big astrophysical whodunnit. Across the Universe, galaxies are being killed and the question scientists want answered is, what’s killing them?

    New research published today by a global team of researchers, based at the International Centre for Radio Astronomy Research (ICRAR), seeks to answer that question. The study reveals that a phenomenon called ram-pressure stripping is more prevalent than previously thought, driving gas from galaxies and sending them to an early death by depriving them of the material to make new stars.

    The study of 11,000 galaxies shows their gas—the lifeblood for star formation—is being violently stripped away on a widespread scale throughout the local Universe.

    Toby Brown, leader of the study and PhD candidate at ICRAR and Swinburne University of Technology, said the image we paint as astronomers is that galaxies are embedded in clouds of dark matter that we call dark matter halos.

    Dark matter is the mysterious material that despite being invisible accounts for roughly 27 per cent of our Universe, while ordinary matter makes up just 5 per cent. The remaining 68 per cent is dark energy.

    “During their lifetimes, galaxies can inhabit halos of different sizes, ranging from masses typical of our own Milky Way to halos thousands of times more massive,” Mr Brown said.

    “As galaxies fall through these larger halos, the superheated intergalactic plasma between them removes their gas in a fast-acting process called ram-pressure stripping.

    “You can think of it like a giant cosmic broom that comes through and physically sweeps the gas from the galaxies.”

    Mr Brown said removing the gas from galaxies leaves them unable to form new stars.

    “It dictates the life of the galaxy because the existing stars will cool off and grow old,” he said.

    “If you remove the fuel for star formation then you effectively kill the galaxy and turn it into a dead object.”

    ICRAR researcher Dr Barbara Catinella, co-author of the study, said astronomers already knew ram-pressure stripping affected galaxies in clusters, which are the most massive halos found in the Universe.

    “This paper demonstrates that the same process is operating in much smaller groups of just a few galaxies together with much less dark matter,” said Mr. Brown. “Most galaxies in the Universe live in these groups of between two and a hundred galaxies,” he said.

    “We’ve found this removal of gas by stripping is potentially the dominant way galaxies are quenched by their surrounds, meaning their gas is removed and star formation shuts down.”

    The study was published in the journal Monthly Notices of the Royal Astronomical Society. It used an innovative technique combining the largest optical galaxy survey ever completed—the Sloan Digital Sky Survey—with the largest set of radio observations for atomic gas in galaxies —the Arecibo Legacy Fast ALFA survey.

    SDSS Telescope at Apache Point, NM, USA
    SDSS Telescope at Apache Point, NM, USA
    Universe map Sloan Digital Sky Survey (SDSS) 2dF Galaxy Redshift Survey
    Universe map Sloan Digital Sky Survey (SDSS) 2dF Galaxy Redshift Survey

    NAIC/Arecibo Observatory, Puerto Rico, USA
    NAIC/Arecibo Observatory, Puerto Rico, USA
    3
    The Arecibo Legacy Fast ALFA Survey

    Mr Brown said the other main process by which galaxies run out of gas and die is known as strangulation.

    “Strangulation occurs when the gas is consumed to make stars faster than it’s being replenished, so the galaxy starves to death,” he said.

    “It’s a slow-acting process. On the contrary, what ram-pressure stripping does is bop the galaxy on the head and remove its gas very quickly—of the order of tens of millions of years—and astronomically speaking that’s very fast.”

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

    Stem Education Coalition

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

    ICRAR is:

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

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

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

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

     
  • richardmitnick 12:06 pm on January 16, 2017 Permalink | Reply
    Tags: ASKAP finally hits the big-data highway, , , , ICRAR, , , , WALLABY - Widefield ASKAP L-band Legacy All-sky Blind surveY   

    From The Conversation for SKA: “The Australian Square Kilometre Array Pathfinder finally hits the big-data highway” 

    Conversation
    The Conversation

    SKA Square Kilometer Array

    SKA

    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

    January 15, 2017
    Douglas Bock
    Director of Astronomy and Space Science, CSIRO

    Antony Schinckel
    ASKAP Director, CSIRO

    You know how long it takes to pack the car to go on holidays. But there’s a moment when you’re all in, everyone has their seatbelt on, you pull out of the drive and you’re off.

    Our ASKAP (Australian Square Kilometre Array Pathfinder) telescope has just pulled out of the drive, so to speak, at its base in Western Australia at the Murchison Radio-astronomy Observatory (MRO), about 315km northeast of Geraldton.

    ASKAP is made of 36 identical 12-metre wide dish antennas that all work together, 12 of which are currently in operation. Thirty ASKAP antennas have now been fitted with specialised phased array feeds, the rest will be installed later in 2017.

    Until now, we’d been taking data mainly to test how ASKAP performs. Having shown the telescope’s technical excellence it’s now off on its big trip, starting to make observations for the big science projects it’ll be doing for the next five years.

    And it’s taking lots of data. Its antennas are now churning out 5.2 terabytes of data per second (about 15 per cent of the internet’s current data rate).

    Once out of the telescope, the data is going through a new, almost automatic data-processing system we’ve developed.

    It’s like a bread-making machine: put in the data, make some choices, press the button and leave it overnight. In the morning you have a nice batch of freshly made images from the telescope.

    Go the WALLABIES

    The first project we’ve been taking data for is one of ASKAP’s largest surveys, WALLABY (Widefield ASKAP L-band Legacy All-sky Blind surveY).

    On board the survey are a happy band of 100-plus scientists – affectionately known as the WALLABIES – from many countries, led by one of our astronomers, Bärbel Koribalski, and Lister Staveley-Smith of the International Centre for Radio Astronomy Research (ICRAR), University of Western Australia.

    They’re aiming to detect and measure neutral hydrogen gas in galaxies over three-quarters of the sky. To see the farthest of these galaxies they’ll be looking three billion years back into the universe’s past, with a redshift of 0.26.

    2
    Neutral hydrogen gas in one of the galaxies, IC 5201 in the southern constellation of Grus (The Crane), imaged in early observations for the WALLABY project. Matthew Whiting, Karen Lee-Waddell and Bärbel Koribalski (all CSIRO); WALLABY team, Author provided

    Neutral hydrogen – just lonely individual hydrogen atoms floating around – is the basic form of matter in the universe. Galaxies are made up of stars but also dark matter, dust and gas – mostly hydrogen. Some of the hydrogen turns into stars.

    Although the universe has been busy making stars for most of its 13.7-billion-year life, there’s still a fair bit of neutral hydrogen around. In the nearby (low-redshift) universe, most of it hangs out in galaxies. So mapping the neutral hydrogen is a useful way to map the galaxies, which isn’t always easy to do with just starlight.

    But as well as mapping where the galaxies are, we want to know how they live their lives, get on with their neighbours, grow and change over time.

    When galaxies live together in big groups and clusters they steal gas from each other, a processes called accretion and stripping. Seeing how the hydrogen gas is disturbed or missing tells us what the galaxies have been up to.

    We can also use the hydrogen signal to work out a lot of a galaxy’s individual characteristics, such as its distance, how much gas it contains, its total mass, and how much dark matter it contains.

    This information is often used in combination with characteristics we learn from studying the light of the galaxy’s stars.

    Oh what big eyes you have ASKAP

    ASKAP sees large pieces of sky with a field of view of 30 square degrees. The WALLABY team will observe 1,200 of these fields. Each field contains about 500 galaxies detectable in neutral hydrogen, giving a total of 600,000 galaxies.

    3
    One of the first fields targeted by WALLABY, the NGC 7232 galaxy group. Ian Heywood (CSIRO); WALLABY team, Author provided

    This image (above) of the NGC 7232 galaxy group was made with just two nights’ worth of data.

    ASKAP has now made 150 hours of observations of this field, which has been found to contain 2,300 radio sources (the white dots), almost all of them galaxies.

    It has also observed a second field, one containing the Fornax cluster of galaxies, and started on two more fields over the Christmas and New Year period.

    Even more will be dug up by targeted searches. Simply detecting all the WALLABY galaxies will take more than two years, and interpreting the data even longer. ASKAP’s data will live in a huge archive that astronomers will sift through over many years with the help of supercomputers at the Pawsey Centre in Perth, Western Australia.

    ASKAP has nine other big survey projects planned, so this is just the beginning of the journey. It’s really a very exciting time for ASKAP and the more than 350 international scientists who’ll be working with it.

    Who knows where this Big Trip will take them, and what they’ll find along the way?

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 4:08 pm on October 28, 2016 Permalink | Reply
    Tags: , , ICRAR, , ,   

    From icrar: “Australian Desert Telescope Views Sky in Radio Technicolor” 

    ICRAR Logo
    International Centre for Radio Astronomy Research

    10.28.16

    Dr Natasha Hurley-Walker (Curtin University, ICRAR)
    E: nhw@icrar.org
    M: +61 426 192 677

    Associate Professor Randall Wayth (Curtin University, ICRAR, CAASTRO)
    E: randall.wayth@icrar.org
    M: +61 418 282 359

    Pete Wheeler, Media Contact, ICRAR
    E: pete.wheeler@icrar.org
    M: +61 423 982 018

    Tamara Hunter, Media Contact, Curtin University
    E: tamara.hunter@curtin.edu.au
    M: +61 (08) 9266 3353

    1
    A ‘radio colour’ view of the sky above a ‘tile’ of the Murchison Widefield Array radio telescope, located in outback Western Australia. 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. Red indicates the lowest frequencies, green the middle frequencies and blue the highest frequencies. Credit: Radio image by Natasha Hurley-Walker (ICRAR/Curtin) and the GLEAM Team. MWA tile and landscape by Dr John Goldsmith / Celestial Visions.

    A telescope located deep in the West Australian outback has shown what the Universe would look like if human eyes could see radio waves.

    Published today in the Monthly Notices of the Royal Astronomical Society, the GaLactic and Extragalactic All-sky MWA, or ‘GLEAM’ survey, has produced a catalogue of 300,000 galaxies observed by the Murchison Widefield Array (MWA), a $50 million radio telescope located at a remote site northeast of Geraldton.

    Lead author Dr Natasha Hurley-Walker, from Curtin University and the International Centre for Radio Astronomy Research (ICRAR), said this is the first radio survey to image the sky in such amazing technicolour.

    “The human eye sees by comparing brightness in three different primary colours – red, green and blue,” Dr Hurley-Walker said.

    “GLEAM does rather better than that, viewing the sky in 20 primary colours.

    “That’s much better than we humans can manage, and it even beats the very best in the animal kingdom, the mantis shrimp, which can see 12 different primary colours,” she said.

    GLEAM is a large-scale, high-resolution survey of the radio sky observed at frequencies from 70 to 230 MHz, observing radio waves that have been travelling through space—some for billions of years.

    “Our team are using this survey to find out what happens when clusters of galaxies collide,” Dr Hurley-Walker said.

    “We’re also able to see the remnants of explosions from the most ancient stars in our galaxy, and find the first and last gasps of supermassive black holes.”

    MWA Director Associate Professor Randall Wayth, from Curtin University and ICRAR, said GLEAM is one of the biggest radio surveys of the sky ever assembled.

    “The area surveyed is enormous,” he said. “Large sky surveys like this are extremely valuable to scientists and they’re used across many areas of astrophysics, often in ways the original researchers could never have imagined,” Associate Professor Wayth said.

    Completing the GLEAM survey with the MWA is a big step on the path to SKA-low, the low frequency part of the international Square Kilometre Array (SKA) radio telescope to be built in Australia in the coming years.

    SKA Square Kilometer Array

    “It’s a significant achievement for the MWA telescope and the team of researchers that have worked on the GLEAM survey,” Associate Professor Wayth said.

    The MWA

    The Murchison Widefield Array (MWA) is a low frequency radio telescope located at the Murchison Radio-astronomy Observatory in Western Australia’s Mid West.

    SKA Murchison Widefield Array, in Western Australia

    The MWA observes radio waves with frequencies between 70 and 320 MHz and was the first of the three Square Kilometre Array (SKA) precursors to be completed.

    A consortium of 13 partner institutions from four countries (Australia, USA, India and New Zealand) has financed the development, construction, commissioning and operations of the facility. Since commencing operations in mid 2013 the consortium has grown to include new partners from Canada and Japan.

    Key science for the MWA ranges from the search for redshifted HI signals from the Epoch of Reionisation to wide-field searches for transient and variable objects (including pulsars and Fast Radio Bursts), wide-field Galactic and extra-galactic surveys, and solar and heliospheric science.

    The SKA

    The Square Kilometre Array (SKA) project is an international effort to build the world’s largest radio telescope, led by SKA Organisation based at the Jodrell Bank Observatory near Manchester, England. Co-located primarily in South Africa and Western Australia, the SKA will be a collection of hundreds of thousands of radio antennas with a combined collecting area equivalent to approximately one million square metres, or one square kilometre. 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.

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

    Stem Education Coalition

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

    ICRAR is:

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

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

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

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

     
  • richardmitnick 7:45 pm on March 7, 2016 Permalink | Reply
    Tags: , , , ICRAR,   

    From ICRAR: “LIGO makes waves with gravitational announcement, and Australian telescopes follow up” 

    ICRAR Logo
    International Centre for Radio Astronomy Research

    7 March, 2016

    Several weeks ago, physicists at The Laser Interferometer Gravitational-Wave Observatory (LIGO) made waves with the announcement that gravitational waves – ripples in space time caused by a violent cosmic event taking place in the distant Universe – had finally been observed 100 years after Albert Einstein predicted their existence.

    Caltech Ligo
    MIT/Caltech Advanced a LIGO, Hanford WA, USA

    Australian researchers and telescopes played an exciting part in the follow-up observations, showcasing the capabilities of the Square Kilometre Array precursors located in the Western Australian outback.

    Research published last month describes the follow-up program that began soon after the gravitational wave candidate was first identified by LIGO in September 2015. Within two days of the trigger, 21 teams responded to the alert and began observations with satellites and ground-based telescopes around the world. Over the next three months, observations were performed using facilities spanning from radio to gamma-ray wavelengths.

    The Australian radio telescopes involved in the EM [?] follow-up are both located at CSIRO’s Murchison Radio-astronomy Observatory (MRO) – the Australian SKA Pathfinder (ASKAP) and the Murchison Widefield Array (MWA).

    SKA ASKAP
    ASKAP

    SKA Murchison Widefield Array
    MWA

    Both instruments offer a wide field of view, high sensitivity and quick response times, and are complemented by high-speed supercomputing capabilities, making them valuable additions to the LIGO/Virgo collaboration.

    With its huge field of view, the MWA was the first radio telescope in the world to respond to the call from LIGO to hunt down the source of the unconfirmed gravity wave detection. Not long after, ASKAP swung into action, using the first of its antennas equipped with a Phased Array Feed (PAF) receiver to make multiple observations of the trigger region over the course of the following week.

    The challenge of conducting follow up work for gravitational wave surveys is that the position of the source is not well know and is located somewhere within a large region of sky. For telescopes with a large field of view, like ASKAP and MWA, this is a great advantage.

    “LIGO gives us two things: the area of sky to look at and the time the trigger started,” explains Keith Bannister, one of the CSIRO astronomers involved in the ASKAP follow-up, “With a wide field of view, good sensitivity and the 1 GHz observing frequency, ASKAP is an ideal instrument for finding EM counterparts. And, we now have the infrastructure in place so that when LIGO detects a trigger, we have the capability to do a follow-up observation.”

    “We’re yet to detect anything, but just to be involved in this program is a great thrill,” he continues, “It’s exciting to think how much more we’ll be able to contribute with the full ASKAP telescope, when all 36 antennas are installed with Mk II PAFs.”

    The MWA, which has been in full operations since mid 2013, has cooperative agreements with LIGO and other telescopes to follow up time-critical astronomical events such as gravitational wave events and gamma-ray bursts. Having no moving parts, the MWA is very agile and can be observing the sky moments after receiving the alert.
    “The MWA automatically accepts alert messages from other instruments like LIGO and begins observing the source in less than eight seconds,” MWA Director Dr Randall Wayth of Curtin University (ICRAR) said.

    “Although there was no detection for this first event, we’re excited about being part of the international electromagnetic follow-up to these events.”
    The MWA is currently undergoing an expansion phase that will double its angular resolution on the sky. This increased resolution will help localise the sources of GW events when a follow-up detection occurs.

    “It’s been fantastic to follow-up this momentous event with the MWA. The unique capabilities of the telescope really shone in this, allowing us to dominate with our coverage of the sky. The hardest part has been keeping this quiet for the last few months,” said MWA project scientist, Professor David Kaplan.
    The sentiment is echoed by ASKAP Project Scientist Lisa Harvey-Smith, who notes that two of the ASKAP Survey Science Projects, VAST and CRAFT, are dedicated to transient searches.

    “It is very exciting for ASKAP to be involved in the international efforts to detect electromagnetic emission from this gravitational wave event. Our PAF receivers make ASKAP a very powerful instrument for detecting radio waves from these events, and our science teams are looking forward to continuing this work as part of the Early Science program that will start this year. ”

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

    Stem Education Coalition

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

    ICRAR is:

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

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

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

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

     
  • richardmitnick 2:16 pm on February 22, 2016 Permalink | Reply
    Tags: , , Galaxy trailed by stunning plume of gas, ICRAR   

    From ICRAR: “Galaxy trailed by stunning plume of gas” 

    ICRAR Logo
    International Centre for Radio Astronomy Research

    22 February, 2016
    Contacts

    Dr Luca Cortese
    ICRAR – The University of Western Australia
    Ph: +61 8 6488 3663
    E: Luca.Cortese@icrar.org

    Pete Wheeler
    Media Contact, ICRAR
    M: +61 423 982 018
    E: Pete.Wheeler@icrar.org

    Astronomers have discovered a spectacular tail of gas more than 300,000 light years across coming from a nearby galaxy.

    The plume is made up of hydrogen gas—the material new stars are made of—and is five times longer than the galaxy itself.

    The discovery was made by an international team of scientists led by Dr Alessandro Boselli at the Laboratoire d’Astrophysique de Marseille in France, and published in the journal Astronomy & Astrophysics.

    International Centre for Radio Astronomy Research astrophysicist Luca Cortese, who is part of the research team, said scientists noticed long ago that the galaxy NGC 4569 contained less gas than expected but they could not see where it had gone.

    “We didn’t have the smoking gun, the clear evidence of direct removal of gas from the galaxy,” he said.

    “Now, with these observations, we’ve seen a huge amount of gas that creates a stream trailing behind the galaxy for the first time.

    “What’s very nice is that if you measure the mass of the stream, it’s the same amount of gas that is missing from the galaxy’s disc.”

    NGC 4569 sits in the Virgo cluster, a group of galaxies 55 million light years from our own Milky Way.

    It is travelling through the cluster at about 1200 kilometres a second, and Dr Cortese said it is this movement that is causing the gas to be stripped from the galaxy.

    “We know that big clusters of galaxies trap a lot of hot gas,” he said.

    “So when a galaxy enters the cluster it feels the pressure of all the gas, like when you feel the wind on your face, and that pressure is able to strip matter away from the galaxy.”

    The discovery was made when the research team used a super-sensitive camera on the Canada France Hawaii Telescope [CFHT]to observe NGC 4569 for longer than ever before.

    CFHT
    CFHT Interior
    CFHT

    Dr Cortese said it could be the first of many galaxies found to have long tails of gas extending from them.

    “It’s pretty exciting because this was just a pilot and we only targeted the brightest spiral galaxy in the Virgo cluster,” he said.

    “We were amazed by what we got… this is really promising because it means it’s very likely we’ll find similar features in many other galaxy clusters.”

    NGC 4569 Galaxy trailed by stunning plume of gas
    The foreground galaxy is NGC 4569 of the Virgo cluster. The red filaments at the right of the galaxy show the hydrogen gas that has been removed. The tail represents about 95 per cent of the gas reservoir the galaxy needs to feed the formation of new stars. Credit: CFHT/Coelum

    Original publication details:

    Spectacular tails of ionised gas in the Virgo cluster galaxy NGC 4569 published in Astronomy & Astrophysics on February 19, 2016. A copy of the paper is available from http://www.aanda.org/articles/aa/pdf/2016/03/aa27795-15.pdf

    Virgo Supercluster
    Virgo Supercluster

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

    Stem Education Coalition

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

    ICRAR is:

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

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

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

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

     
    • B. Doyle 3:27 pm on February 22, 2016 Permalink | Reply

      Nice post, I went to the CFHT site and found the original paper, it was quite an interesting read. I’ve always wanted to be an observational astronomer, but I can’t foresee ever becoming one 😛

      Like

  • richardmitnick 8:38 pm on December 22, 2015 Permalink | Reply
    Tags: , , GAMA Galaxy Survey, ICRAR   

    From ICRAR: “Scientists measure Slow Death of the Universe” [I hope you read this, it was a ton of work] 

    ICRAR Logo
    International Centre for Radio Astronomy Research

    August 10th, 2015 [Just found this article. This material was covered in an article from ESO 2015/9/10, but here there are an abundance of better graphics, so, it is worth a look.]

    Contact Details:
    Professor Simon Driver, ICRAR – UWA
    Ph: +61 400 713 514 | E: Simon.Driver@icrar.org

    Professor Andrew Hopkins, Australian Astronomical Observatory
    Ph: +61 432 855 049 | E: Andrew.Hopkins@aao.gov.au

    Dr Luke Davies, ICRAR – UWA
    Ph: +61 466 277 672 | E: Luke.Davies@icrar.org

    Pete Wheeler, ICRAR Media Contact
    Ph: +61 423 982 018 | E: Pete.Wheeler@icrar.org

    An international team of astronomers studying 200,000 galaxies has measured the energy generated within a large portion of space more precisely than ever before, discovering that it’s only half what it was 2 billion years ago and fading – the Universe is slowly dying.

    Researchers from the International Centre for Radio Astronomy Research (ICRAR) in Western Australia used seven of the world’s most powerful telescopes to observe galaxies at 21 different wavelengths from the far ultraviolet to the far infrared.

    Initial observations were conducted using the Anglo-Australian Telescope in New South Wales and supporting observations were made by two orbiting space telescopes operated by NASA, GALEX and WISE and another belonging to the European Space Agency, Herschel.

    NASA Galex telescope
    NASA/GALEX

    NASA Wise Telescope
    NASA/WISE

    ESA Herschel
    ESA/Herschel

    The research is part of the Galaxy and Mass Assembly (GAMA) project, the largest multi-wavelength survey ever put together.

    “We used as many space and ground-based telescopes we could get our hands on, to measure the energy output of over 200,000 galaxies across as broad a wavelength range as possible,” says ICRAR Professor Simon Driver, who presented the findings at the International Astronomical Union’s General Assembly in Honolulu.
    _____________________________________________________
    GAMA is a project to exploit the latest generation of ground-based and space-borne survey facilities to study cosmology and galaxy formation and evolution.

    At the heart of this project lies the GAMA spectroscopic survey of ~300,000 galaxies down to r < 19.8 mag over ~286 deg2, carried out using the AAOmega multi-object spectrograph on the Anglo-Australian Telescope (AAT) by the GAMA team. This project was awarded 210 nights over 7 years (2008–2014) and the observations are now completed. This survey builds on, and is augmented by, previous spectroscopic surveys such as the Sloan Digital Sky Survey (SDSS), the 2dF Galaxy Redshift Survey (2dFGRS) and the Millennium Galaxy Catalogue (MGC).

    AAO Anglo Australian Telescope Exterior
    AAO Anglo Australian Telescope Interior
    AAT

    SDSS Telescope
    SDSS telescope

    On the imaging side, GAMA uses public data as well as conducting its own campaigns. In addition, the GAMA team has coordinated survey regions and negotiated data sharing agreements with a number of independent imaging survey teams:
    Facility / Survey
    Public surveys: Sloan SDSS
    United Kingdom Infrared Telescope (UKIRT) UKIDSS-LAS

    UKIRT
    UKIRT interior
    UKIRT
    GAMA campaigns: Galaxy Evolution Explorer (GALEX) GALEX-GAMA
    Image is above
    (GMRT) GMRT-GAMA
    Giant Metrewave Radio Telescope
    GMRT

    Surveys connected to GAMA:
    VLT Survey Telescope (VST) KiDS

    ESO VLT Survey telescope
    ESO VLT Survey telescope
    VLT Survey telescope
    VISTA VIKING
    ESO Vista Telescope
    VISTA
    CFHT CFHTLenS
    CFHT Telescope
    CFHT nterior
    CFHT
    ESA/Herschel H-ATLAS
    Image is above
    ASKAP DINGO
    SKA ASKAP
    ASKAP
    ESA/XMM-Newton) XMM-XXL
    ESA XMM Newton
    ESA/XMM-Newton

    Wide field Infra-red Survey Explorer (WISE)
    Image is above

    The main objective of GAMA is to study structure on scales of 1 kpc to 1 Mpc. This includes galaxy clusters, groups, mergers and coarse measurements of galaxy structure (i.e., bulges and discs). It is on these scales where baryons play a critical role in the galaxy formation and subsequent evolutionary processes and where our understanding of structure in the Universe breaks down.

    Our primary goal is to test the CDM paradigm of structure formation. In particular, the key scientific objectives are:

    To test modified theories of gravity by measuring the growth rate of structure; the CDM model by measuring the halo mass function; and galaxy formation models by measuring the star formation efficiency in groups.
    To measure the connection between star formation fuelling, stellar mass build-up and feedback processes.
    To uncover the detailed mechanisms that govern the build-up of the stellar content of galaxies.
    To directly measure the recent galaxy merger rate as a function of mass, mass ratio, local environment and galaxy type.

    To address these goals, GAMA is creating an extraordinary multi-wavelength photometric and spectroscopic dataset with outstanding value to both the large-scale structure and galaxy evolution communities. By virtue of its unrivaled combination of area, spectroscopic depth, high spatial resolution and broad wavelength coverage the GAMA dataset will be uniquely capable of advancing low and intermediate-redshift galaxy studies.

    More details on GAMA and its science case can be found in our proposals (2007, 2010) and in this article.

    The survey data, released to astronomers around the world, includes 200,000 galaxies each measured at 21 wavelengths from the ultraviolet to the far infrared and will help scientists better understand how different types of galaxies form.

    1
    A galaxy from the GAMA survey observed at 20 different wavelengths from the far ultraviolet to the far infrared. Credit: ICRAR / GAMA

    6
    A galaxy from the GAMA survey observed at different wavelengths from the far ultraviolet to the far infrared. Credit: ICRAR / GAMA.

    7
    A galaxy from the GAMA survey observed at different wavelengths from the far ultraviolet to the far infrared. The inset graph shows how much energy is being generated at the different wavelengths. Credit: ICRAR / GAMA.

    Professor Driver, who heads up the GAMA team, says the study set out to map and model all of the energy generated within a set volume of space.

    All energy in the Universe was created in the Big Bang with some portion locked up as mass. Stars shine by converting this mass into energy as described by Einstein’s famous equation E=MC2.

    “While most of the energy sloshing around was created in the aftermath of the Big Bang, additional energy is constantly being released by stars as they fuse elements like hydrogen and helium together,” Professor Driver says.

    “This newly released energy is either absorbed by dust as it travels through the host galaxy, or escapes into intergalactic space and travels until it hits something such as another star, planet, or very occasionally a telescope mirror.”

    The fact that the Universe is slowly fading has been known since the late 1990s but this work shows that it’s happening across all wavelengths from the ultraviolet to the infrared, representing the most comprehensive assessment of the energy output of the nearby Universe.

    “The Universe is fated to decline from here on in, like an old age that lasts forever. The Universe has basically plonked itself down on the sofa, pulled up a blanket and is about to nod off for an eternal doze,” Professor Driver says.

    The team of researchers hope to expand the work to map energy production over the entire history of the Universe. To do this, they will use a swathe of new facilities including the world’s largest radio telescope, the Square Kilometre Array, due to be built in Australia and South Africa in the next decade.


    Fly through of the GAMA Galaxy Survey
    download mp4 video here.

    The Galaxy and Mass Assembly catalogue is a detailed map of the Universe showing where galaxies are in 3D. This simulated flythrough shows the real positions and images of the galaxies that have been mapped so far. Distances are to scale, but the galaxy images have been enlarged for your viewing pleasure.

    Credit: Made by Will Parr, Dr. Mark Swinbank and Dr. Peder Norberg (Durham University) using data from the SDSS and the GAMA surveys. This work was supported by the Ogden Trust, STFC and the Royal Society. Music by Holly Broadbent.


    Fly through of the GAMA Galaxy Survey with voice over
    download mp4 video here.

    3
    The distribution of galaxies as mapped by various Australia, US and European survey teams. In total we have mapped the locations of over 4million galaxies that can be used to study the evolution of mass, energy and structure in the Universe over the past few billion years. Credit ICRAR / GAMA.

    5
    The distribution of galaxies as mapped by various Australia, US and European survey teams. In total we have mapped the locations of over 4million galaxies that can be used to study the evolution of mass, energy and structure in the Universe over the past few billion years. Credit ICRAR / GAMA.

    Further Information:
    Professor Driver will present this work at the General Assembly of the International Astronomical Union in Honolulu on Monday, August 10.

    The Galaxy and Mass Assembly Survey, or GAMA, is a collaboration involving nearly 100 scientists from more than 30 universities located in Australia, Europe and the United States.

    ICRAR is a joint venture between Curtin University and The University of Western Australia with support and funding from the State Government of Western Australia.

    Original publication details:

    Galaxy And Mass Assembly (GAMA): Panchromatic Data Release (far-UV—far-IR) and the low-z energy budget submitted to the Monthly Notices of the Royal Astronomical Society. Available from http://www.simondriver.org/mwavev02.pdf

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

    Stem Education Coalition

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

    ICRAR is:

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

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

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

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

     
  • richardmitnick 8:54 pm on December 14, 2015 Permalink | Reply
    Tags: , , Clumpy galaxies and star formation, ICRAR   

    From ICRAR: “New spin on star-forming galaxies” 

    ICRAR Logo

    International Centre for Radio Astronomy Research

    12.14.15

    Dr Danail Obreschkow
    ICRAR – The University of Western Australia
    M: +61 424 662 252
    E: Danail.Obreschkow@icrar.org

    Professor Karl Glazebrook
    Swinburne University
    M: +61 416 094 732
    E: kglazebrook@swin.edu.au

    Pete Wheeler
    Media Contact
    M: +61 423 982 018
    E: Pete.Wheeler@icrar.org

    1
    Regular spiral galaxies, such as the ‘Whirlpool galaxy’ on the left, form far fewer stars than the clumpy galaxy on the right.
    The blue regions have the least star-forming gas and red-yellow regions have the most.
    Credit: Dr Danail Obreschkow, ICRAR. Image uses data from the Hubble Space Telescope.

    NASA Hubble Telescope
    NASA/ESA Hubble

    Australian researchers have discovered why some galaxies are “clumpy” rather than spiral in shape—and it appears low spin is to blame.

    The finding challenges an earlier theory that high levels of gas cause clumpy galaxies and sheds light on the conditions that brought about the birth of most of the stars in the Universe.

    Lead author Dr Danail Obreschkow, from The University of Western Australia node of the International Centre for Radio Astronomy Research (ICRAR), said that ten billion years ago the Universe was full of clumpy galaxies but these developed into more regular objects as they evolved.

    He said the majority of stars in the sky today, including our five billion-year-old Sun, were probably born inside these clumpy formations.

    “The clumpy galaxies produce stars at phenomenal rates,” Dr Obreschkow said.

    “A new star pops up about once a week, whereas spiral galaxies like our Milky Way only form about one new star a year.”

    The research team—a collaboration between ICRAR and Swinburne University of Technology—focused on a few rare galaxies, known as the DYNAMO galaxies.

    They still look clumpy even though they’re seen “only” 500 million years in the past.

    Dr Obreschkow said looking at galaxies 500 million years ago was like looking at a passport photo taken a year ago.

    “We see that galaxy the way it probably looks now… something could have happened to it but it’s very unlikely,” he said.

    “The galaxies that are 10 billion light years away, that’s comparable to a picture from when you were three or four years old, that’s very different.”

    The team used the Keck and Gemini observatories in Hawaii to measure the spin of the galaxies, along with millimetre and radio telescopes – “NOEMA and VLA interferometres (and some circumstantial data from the Arecibo dish”-to measure the amount of gas they contained.

    Keck Observatory
    Keck Observatory Interior
    Keck Observatory

    Gemini North telescope
    GEMINI North GMOS
    Gemini North

    IRAM NOEMA interferometer
    IRAM/NOEMA

    NRAO VLA
    NRAO/VLA

    Arecibo
    Arecibo Observatory

    Dr Obreschkow said the DYNAMO galaxies had a low spin and this was the dominant cause of their clumpiness, rather than their high gas content as previously thought.

    “While the Milky Way appears to have a lot of spin, the galaxies we studied here have a low spin, about three times lower,” he said.

    Swinburne University astronomer Professor Karl Glazebrook, co-author and leader of the survey team, said the finding was exciting because the first observation that galaxies rotate was made exactly 100 years ago.

    “Today we are still revealing the important role that the spin of the initial cloud of gas plays in galaxy formation,” he said.

    “This novel result suggests that spin is fundamental to explaining why early galaxies are gas-rich and lumpy while modern galaxies display beautiful symmetric patterns.”

    The research was published today in The Astrophysical Journal.

    Original publication details:

    ‘Low Angular Momentum in Clumpy, Turbulent Disk Galaxies’ published in The Astrophysical Journal on 14th December, 2015. A copy of the paper is available from http://arxiv.org/pdf/1508.04768v2.pdf.

    The team:

    Danail Obreschkow [International Centre for Radio Astronomy Research, Uni. of Western Australia]; Karl Glazebrook [Centre for
    Astrophysics & Supercomputing, Swinburne Uni. of Technology, PO Box 218, Hawthorn, VIC 3122, Australia], Robert Bassett [Centre for
    Astrophysics & Supercomputing, Swinburne Uni. of Technology], David B. Fisher [Centre for Astrophysics & Supercomputing, Swinburne Uni. of Technology]; Roberto G. Abraham [Department of Astronomy and Astrophysics, Uni. of Toronto, 50 St George St, Toronto, ON M5S3H4, Canada]; Emily Wisnioski [Max Planck Institut fur extraterrestrische Physik, Postfach 1312, Giessenbachstr., D-85741 Garching, Germany], Andrew W. Green [Australian Astronomical Observatory, PO Box 915, North Ryde, NSW 1670, Australia], Peter J. McGregor [Research School of Astronomy and Astrophysics, Australian National Uni., Cotter Rd, Weston, ACT 2611, Australia], Ivana Damjanov [Harvard-Smithsonian CfA, 60 Garden St., MS-20, Cambridge, MA 02138, USA], Attila Popping [International Centre for Radio Astronomy Research, Uni. of Western Australia];and Inger Jrgensen [Gemini Observatory, 670 N. A’ohoku Pl., Hilo, HI 96720, USA]

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

    Stem Education Coalition

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

    ICRAR is:

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

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

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

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

     
  • richardmitnick 9:06 pm on November 26, 2015 Permalink | Reply
    Tags: , , ICRAR, ,   

    From ICRAR: “Scientists spot jets from supermassive black hole snacking on a star” 

    International Center for Radio Astronomy Research

    International Centre for Radio Astronomy Research

    27 November, 2015
    Contacts

    Dr Gemma Anderson
    ICRAR – Curtin University
    Ph: +61 8 9266 3577
    M: +61 408 955 483
    E: Gemma.Anderson@icrar.org

    Dr James Miller-Jones
    ICRAR – Curtin University
    Ph: +61 8 9266 3785
    M: +61 488 484 825
    E: James.Miller-Jones@icrar.org

    Pete Wheeler
    Media Contact
    M: +61 423 982 018
    E: Pete.Wheeler@icrar.org

    1
    An artist’s impression of a star being drawn toward a black hole and destroyed, triggering a jet of plasma made from debris left over from the stars destruction.
    Credit: Modified from an original image by Amadeo Bachar.

    Scientists have discovered a hungry black hole swallowing a star at the centre of a nearby galaxy.

    The supermassive black hole was found to have faint jets of material shooting out from it and helps to confirm scientists’ theories about the nature of black holes.

    The discovery was published today in the journal Science.

    Astrophysicist Dr Gemma Anderson, from the Curtin University node of the International Centre for Radio Astronomy Research (ICRAR), said a supermassive black hole swallowing a star is an extreme event in which the star gets ripped apart.

    “It’s very unusual when a supermassive black hole at the centre of a galaxy actually eats a star, we’ve probably only seen about 20 of them,” she said.

    “Everything we know about black holes suggests we should see a jet when this happens but until now they’ve only been detected in a few of the most powerful systems.

    “Now we’ve finally found one in a more normal event.”

    The discovery is the first time scientists have been able to see both a disk of material falling into a black hole, known as an accretion disk, and a jet in a system of this kind.

    ICRAR astrophysicist Dr James Miller-Jones compared the energy produced by the jets in this event to the entire energy output of the Sun over 10 million years.

    He said it was likely all supermassive black holes swallowing stars launched jets but this discovery was made because the black hole is relatively close to Earth and was studied soon after it was first seen.

    The black hole is only 300 million light years away from us and the team (led by Dr Sjoert van Velzen from The Johns Hopkins University in the USA) were able to make their first observations only three weeks after it was found.

    “We’ve shown that it was just a question of looking at the right time and with enough sensitivity,” Dr Miller-Jones said.

    “Then you can show that a jet exists right at the point you think it should.”

    Dr Anderson began the research while working with the 4 PI SKY team at Oxford University but moved to Western Australia in September.

    She said the event was first picked up by the All-sky Automated Survey for Supernovae (ASAS-SN), which is pronounced ‘assassin’ by astronomers, and followed up with the Arcminute Microkelvin Imager (AMI), a radio telescope, located near Cambridge.

    Arcminute Microkelvin Imager
    Arcminute Microkelvin Imager (AMI) Small Array

    “Hopefully with the increased sensitivity of future telescopes like the Square Kilometre Array we’ll be able to detect jets from other supermassive black holes of this type and discover even more about them,” Dr Anderson said.

    Further information:
    For more information about the 4 PI SKY project visit http://www.4pisky.org

    ICRAR is a joint venture between Curtin University and The University of Western Australia with support and funding from the State Government of Western Australia.

    Original publication details:

    ‘A radio jet from the optical and X-ray bright stellar tidal disruption flare ASASSN-14li’ published in the journal Science on 26/11/2015. A copy of the paper is available upon request. ​

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

    Stem Education Coalition

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

    ICRAR is:

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

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

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

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

     
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