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The Square Kilometre Array – Australia Misses Out By GEOFF GRAHAM One of the first ASKAP dishes to be constructed at the Murchison Radio-Astronomy Observatory in Western Australia. Photo credit: Paul Bourke and Jonathan Knispel. Supported by WASP (UWA), iVEC, ICRAR and CSIRO. Most readers will have heard of the Square Kilometre Array (SKA) radio telescope project which SILICON CHIP reported on in the December 2011 issue. It was supposed to be a bidding contest between Australia and South Africa. In simple terms, South Africa won and we lost. But that’s not the end of the story. 16  Silicon Chip siliconchip.com.au An artist’s impression of the high-frequency dishes that will be installed in the Karoo desert in South Africa. These are the type of antenna that we normally associate with a radio telescope. Photo credit: SKA Organisation/Swinburne Astronomy. T HE SKA IS A $2.5 billion international project to build a giant radio telescope using thousands of individual dishes spread over thousands of kilometres. Using immensely powerful computers, yet to be developed, scientists hope to combine the signals from all these dishes to give ultra-clear and sensitive images of the radio sky. With such a big project on offer, the competition for the right to host the SKA was fierce and it came down to a contest between South Africa and Australia/New Zealand. Australia’s proposed site was in the Murchison region of Western Australia and we even went as far as building the $220 million ASKAP radio telescope on the site, partially to demonstrate our capability in this field. As was widely reported on 25th May 2012, the SKA Organisation decided to share the telescope between the two contenders. This seemed like a simple enough decision and a win-win for both sides. But is it? Making the decision To evaluate the competing bids, the SKA Organisation (headquartered in the UK) formed a Site Advisory Committee and they concluded that either site was suitable. In the end, their recommendation was to host the siliconchip.com.au project in South Africa. This advice was based mostly on technical factors, which included a more favourable layout of the array in southern Africa and lower operating costs (political, socio-economic and financial factors represented just 2% of the decision). By many reports, this recommendation led to a fierce debate within the SKA community, with non-technical issues being raised. According to reports, the debate became acrimonious, with allegations of dirty tricks and political high-handedness. The public was unaware of this battle but a sure indication was the premature leak of the committee’s recommendation to The Sydney Morning Herald in March. The final decision on the telescope’s location was the responsibility of the international members of the SKA Organisation who did not bid (Canada, China, Italy, the Netherlands and the United Kingdom). Their debate was held behind closed doors but it has been reported that the three European countries favoured South Africa, perhaps because it was closer to Europe and they would have better control over the project. Reports also claim that Canada and China favoured the Australia/NZ bid because of the better infrastructure in Australia and the political instability of some countries in the South African consortium. Faced with this stand-off, the de­ cision was a typical bureaucrat’s solution; split the project between the competing countries. Practical results The next issue for the SKA Organisation was how to divide up the project. Because Africa and Australia are on different parts of the globe they see different parts of the sky at any one time. This means that the SKA could not simply share the telescope’s dishes between the countries, as they all had to be looking at the same part of the sky at the same time. So the decision was made to deploy the main telescope with all the high-frequency dishes to South Africa while Australia would have the lowfrequency aperture array scheduled for deployment later as part of Phase 2. In practical terms, this means that the majority of the telescope will be built in Africa. The official statement describes it as a split of two thirds to Africa and one third to Australia/NZ but given that full construction of the less important low-frequency aperture arrays will only commence in Phase 2 (around 2020), most of the observable activity will be in Africa. In Australia, this was reported as July 2012  17 The Dense Aperture Array will be used to survey the mid-frequencies and will also be installed at the SKA site in the Karoo desert in South Africa. Photo credit: SKA Organisation/Swinburne Astronomy. a “win-win” situation but in South Africa it was heralded as a triumph for Africa while deploring the associated compromise forced on to them by political expediency. For New Zealand, the result is quite disappointing. The low-frequency aperture array will be in the Murchison region of Western Australia and it is This map shows the proposed layout of the high-frequency dish array throughout Africa. Credit: SKA South Africa. 18  Silicon Chip difficult to see how this could be extended to New Zealand. Three types of detectors The SKA was envisaged from the start as consisting of three types of detectors: (1) The high-frequency dishes, ie, the traditional steerable dish types that most people associate with a radio telescope; (2) A medium-frequency array covering roughly 0.5GHz to 3GHz. This will be primarily a survey instrument, exploring the evolution of galaxies, dark energy, transient sources and the realm of strong gravity; and (3) A low-frequency aperture array covering about 70-300MHz which will be used to investigate the epoch of reionisation and some transient sources. The high-frequency dishes and the medium-frequency array will be installed in Africa while the lowfrequency aperture array will be installed in Australia. Both the medium and low-frequency arrays are new technology and both countries will experiment with them in Phase 1 but full construction will only start in Phase 2. The low-frequency aperture array to be installed in WA will probably consist of arrays of “droopy dipoles”, one for each polarisation and arranged into stations in a fixed pattern on the ground. The signals from each dipole will be combined using computers to observe a number of large areas of the sky simultaneously. This is different from the traditional telescope where a dish is aimed at the source and the signal is bounced from its surface to the focus where it is captured. The future of the SKA The decision on where to locate the SKA is not by any means the end of the story. One of the big issues facing the SKA will be to obtain sufficient funding to begin construction. To date, only a small amount of seed funding has been provided by the SKA member countries and this has been used for items such as the construction of the SKA’s headquarters and staff salaries. Soon, serious funding of hundreds of millions of dollars will be required and it is difficult to see how hardpressed countries like Italy and the UK can find this sort of money when their citizens are forced to suffer under government-imposed “fiscal austerity”. Non-European countries like the USA are not in a much better position and given the world’s present financial crisis, $2.5 billion is a lot of money to spend on something that could be siliconchip.com.au Above: artist’s impressions of the low-frequency array that’s destined for the Murchison in WA. Phase 1 of the SKA project will involve experimenting with them while construction will start in Phase 2 (2020 or later). Photo credit: SKA Organisation/Swinburne Astronomy. Above: an elevated view of four of CSIRO’s new ASKAP antennas at the Murchison Radio-Astronomy Observatory in Western Australia, October 2010. Photo credit: Ant Schinckel, CSIRO. deferred until times are better. Consequently, it is very likely that the various target dates for the project will slip and that could push out the siliconchip.com.au date for the construction of the lowfrequency aperture array in Australia even further than 2020. In fact, it might never happen at all. Another issue that the SKA has to face is the effects of creeping bureaucracy and national rivalries, some of which has already become apparent in July 2012  19 The Full Statement From The SKA Organisation The Members of the SKA Organisation today agreed on a dual site solution for the Square Kilometre Array telescope, a crucial step towards building the world’s largest and most sensitive radio telescope. The ASKAP and MeerKAT precursor dishes will be incorporated into Phase I of the SKA which will deliver more science and will maximise on investments already made by both Australia and South Africa. The majority of the members were in favour of a dual-site implementation model for SKA. The members noted the report from the SKA Site Advisory Committee that both sites were well suited to hosting the SKA and that the report provided justification for the relative advantages and disadvantages of both locations, but that they identified Southern Africa as the preferred site. The members also received advice from the working group set up to look at dual site options. The majority of SKA dishes in Phase 1 will be built in South Africa combined with MeerKAT. Further SKA dishes will be added to the ASKAP array in Australia. All the dishes and the mid frequency aperture arrays for Phase II of the SKA will the site-selection process. While some major science projects like the Large Hadron Collider at CERN have avoided this problem, the international fusion reactor project (ITER) under construction in the south of France illustrates just what can go wrong with a giant project funded by many competitive countries. This latter project has had numerous cost overruns and delays, partially due to the bureaucratic squabbles between the seven major countries involved. There are plenty of examples where a section of the project designed and built by one country will not integrate with another section produced by a different country. The has resulted in arguments, accusations and a project that has been delayed time and time again. Australia’s SKA Pathfinder The Australian SKA Pathfinder 20  Silicon Chip be built in Southern Africa while the low frequency aperture array antennas for Phase I and II will be built in Australia/New Zealand. “This hugely important step for the project allows us to progress the design and prepare for the construction phase of the telescope. The SKA will transform our view of the Universe; with it we will see back to the moments after the Big Bang and discover previously unexplored parts of the cosmos” says Dr Michiel van Haarlem, Interim Director General of the SKA Organisation. The SKA will enable astronomers to glimpse the formation and evolution of the very first stars and galaxies after the Big Bang, investigate the nature of gravity, and possibly even discover life beyond Earth. “Today we are a stage closer to achieving our goal of building the SKA. This position was reached after very careful consideration of information gathered from extensive investigations at both candidate sites,” said Professor John Womersley, Chair of the SKA Board of Directors. “I would like to thank all those involved in the site selection process for the tremendous work they have put in to enable us to reach this point”. (ASKAP) project is currently under construction by the CSIRO in the Murchison region of Western Australia, at the same site proposed for the SKA. Australia has invested a lot of money (over $200M) on this project and it is tempting to ask what effect the recent SKA announcement will have. After all, it was touted as a demonstration of Australia’s capabilities in the competition to attract the SKA to Australia. In fact, with ASKAP, Australia has done a great deal more than South Africa in committing funds and building something concrete. The ASKAP is a great radio tele­ scope in its own right and it will be many years before the SKA, ultimately to be built in Africa, will be in a position to eclipse it. Even then there is a lot of sky to look at and many scientists will queue up to use the ASKAP for projects that cannot be done using the SKA. Factors taken into account during the site selection process included levels of radio frequency interference, the long term sustainability of a radio quiet zone, the physical characteristics of the site, long distance data network connectivity, the operating and infrastructure costs as well as the political and working environment. The agreement was reached by the Members of the SKA Organisation who did not bid to host the SKA (Canada, China, Italy, the Netherlands and the United Kingdom). The Office of the SKA Organisation will now lead a detailed definition period to clarify the implementation. Scientists and engineers from around the world, together with industry partners, are participating in the SKA project which is driving technology development in antennas, data transport, software and computing, and power. The influence of the SKA project extends beyond radio astronomy. The design, construction and operation of the SKA have the potential to impact skills development, employment and economic growth in science, engineering and associated industries, not only in the host countries but in all partner countries. A further vote of confidence in the ASKAP is the fact that the SKA project also plans to invest in it by adding more dishes. Money well spent The ASKAP has, and will continue to provide, a solid base for Australia to develop cutting-edge electronics and computer technology, train engineers and keep high-profile scientists in the country where their expertise can help budding scientists. In this regard, the money is well spent, despite the decision regarding the SKA. Looking further afield, data from the ASKAP and the SKA will be freely available to all scientists, regardless of which countries host the telescopes. Researchers from anywhere will be able to use this data to gain greater insights into the cosmos and have the opportunity to make great discoveries that will benefit all of humanity. SC siliconchip.com.au