The Square Kilometre Array, or SKA, will be the world's largest radio telescope - designed to enable transformational science that will change our understanding of the Universe.
Australia is a member of the international partnership established to build the world’s most powerful radio astronomy facility - the Square Kilometre Array (SKA) Observatory. The SKA Observatory has sites on three continents, with telescopes in Australia and South Africa, and headquarters in the United Kingdom.
More of our partners include Canada, China, France, Germany, India, Italy, Netherlands, Portugal, Spain, Sweden and Switzerland. Each country is contributing significant expertise towards engineering this next-generation facility.
What is the Square Kilometre Array?
The Square Kilometre Array will consist of two radio-telescopes, one in Australia (Low), and one in South Africa (Mid). The two telescopes will observe the sky at different radio frequencies and complement each other scientifically.
We will be hosting the SKA-Low telescope at our Murchison Radio-astronomy Observatory (MRO), in Western Australia. It will consist of an array of 131,072 'Christmas tree-shaped' antennas, grouped in 512 stations, each with 256 antennas. A number of these antenna stations will be placed in the centre and the rest will span out along three spiral arms, stretching 65 kilometres end to end. SKA-Low will operate at frequencies between 50 and 350 MHz.
SKA-Mid will be located at the South African Radio Astronomy Observatory (SARAO). It will consist of an array of 197 dish antennas, each 15 metres in diameter, dotted across its location in the Karoo desert, with 150 kilometres separating the two most distant dishes. SKA-Mid will operate between 350 MHz and 14 GHz
This is radio astronomy on an immense scale. Spreading thousands of antennas over huge distances will enable very fine resolution imaging, revealing the Universe in more detail than we've ever seen before.
The SKA will give astronomers insight into the formation and evolution of the first stars and galaxies, the role of cosmic magnetism, the nature of gravity, and possibly even life beyond Earth.
World-class astronomy in the Australian outback
The SKA is Australia's first opportunity to co-host a mega science facility and we're looking forward to hosting SKA-Low at the MRO.
With the support of the Australian and Western Australian Governments, we established the MRO in 2009. Like light pollution in big cities limits how much of the night sky you can see with your eyes or with an optical telescope, cities and towns also generate radio interference that limits what radio telescopes can 'see'.
The Murchison region was selected for its ideal vantage point from which the SKA and its Australian precursor telescopes could observe the best area of the sky. The weather patterns are relatively stable, and it is accessible to the city of Geraldton though sufficiently far enough away from city-generated radio frequency interference. The SKA project is a multi-generational project that will operate for at least 50 years, so these environmental and socio-geographic considerations were critical in site selection.
The MRO is contained within the 3,500 square kilometre Boolardy Station that surrounds it. Boolardy is one of 29 pastoral stations in the Murchison Shire which covers an area of 49,500 square kilometres. The Murchison is the size of a small European country but with a population of only 113 people! It is at this remote location that works so well for radio astronomy.
In 2011 the Australian Communications and Media Authority (ACMA) created the Australian Radio-Quiet Zone WA (ARQZWA). This Federal legislation is supported by the Western Australian government. The ARQZWA is centred on the MRO and radio astronomy is the primary user of spectrum in the central part of the zone (within a 70 km radius). For the lowest frequency range, the ARQZWA extends to 260 km from the MRO. The MRO 'radio quiet zone is a mechanism for managing radio frequency emissions to ensure the proper functioning of the telescopes.
The MRO also enjoys strong support from the local community, including the Wajarri Yamaji who are the traditional owners of the MRO site.
Working with our local community
The SKA has a light impact on the land compared with a resources project. There is great deal of flexibility in positioning SKA infrastructure, which means significant heritage sites can be avoided.
Wajarri Elders and heritage experts along with archaeologists, ethnologists, Department of Industry representatives and CSIRO staff are carefully walking across the land that’s proposed for SKA construction. This area is about eight square kilometres of the total 4,400 square kilometres – around 0.18% – of the MRO.
In the 'walkovers', areas are categorised into levels of significance and recorded. Alternative locations and routes are examined to avoid any impact on the heritage areas. Preservation zones are already being created and these areas are excluded from the SKA project.
A Cultural Heritage Management Plan will control future project activities to ensure ongoing protection for Wajarri Yamaji heritage. During the construction phase, Wajarri site monitors will track and witness construction activities to ensure day-to-day compliance with the Plan.
Wajarri Yamaji will also be able to continue to access the MRO to exercise their native title rights with a couple of small exceptions such as the power station, which will be very carefully fenced off because of concerns about health and safety.
CSIRO and our SKA project partners recognise the Wajarri Yamaji as the traditional owners of the MRO site, and have been proactive in protecting Wajarri Yamaji heritage for the SKA project.
The Australian SKA Office and CSIRO are currently negotiating an Indigenous Land Use Agreement with the Wajarri Yamaji for the SKA. This agreement will provide sustainable and intergenerational benefits in areas such as enterprise and training, education and culture. The agreement is expected to be finalised ahead of the start of SKA construction.
Building the telescopes of tomorrow
Our role in the SKA project builds on decades of Australian ingenuity that places us among the best in the world in developing technologies for radio astronomy and operating national facilities for the benefit of the scientific and broader communities. As well as playing the major role of developing the site for the SKA-Low telescope in Australia, we're working with industry, universities and other key science organisations on the final SKA design, prototyping and testing of all the telescope elements.
- We lead the Infrastructure Australia team which is developing the MRO site facilities for SKA-Low, including a clean energy power system.
- Our engineers are collaborating with international partners to develop the most efficient central signal processing system, like the brain, for the telescope. This system combines raw data from the many thousands of antennas and sends it to a super computer to create astronomical images.
- Bringing all the parts together is our Assembly, Integration and Verification team which will oversee the telescope elements starting to function as a whole system.
- We also contribute to several other SKA consortia and lead the development of innovative receivers called phased array feeds which are under consideration for the SKA.
The SKA is a major opportunity for international collaboration and to showcase Australia's science and technology capabilities internationally.
Managing the data deluge
The SKA will generate data on the scale of petabits, or a million billion bits, per second – more than the global internet rate today. We're building supercomputers to process the enormous amounts of data.
Initially, the data from the SKA-Low antennas in Western Australia will flow into a custom supercomputing facility on site in the Murchison where initial processing of the data will take place. From there, it will be transferred via fibre-optic cable to the Pawsey Supercomputing Centre in Perth for further processing and imaging. The SKA-Low telescope will generate 300 petabytes of data per year. SKA-Mid will generate the same amount of data!
Working with the Australian SKA Office and ICRAR in Perth, we are establishing a regional SKA data centre (SRC). Telescope data is likely to be transferred to international telescope users from the SRC, via new and existing undersea cables, from Perth to Singapore, and then onwards around the world.
Our Australian SKA Pathfinder (ASKAP) radio telescope is demonstrating the high-performance processing required to meet the SKA data challenges. Using the Pawsey supercomputer and custom-written software developed at CSIRO, we produce science-ready datasets of many Terabytes for each observation. These data are made freely available to the global astronomy community through ASKAP's science archive.
Collaborating for the SKA
Along with the Australian and Western Australian Governments, we are very proud and excited to be a principal partner in Australia's involvement in the SKA. We're also working closely with industry to provide innovative, cost-effective solutions for the SKA.
We acknowledge the Wajarri Yamaji as the traditional owners of the Murchison Radio-astronomy Observatory site.