australia and the square kilometre array

Australia is playing a significant part in the development of the Square Kilometre Array (SKA), the international radio telescope for the 21st Century.Australia has been at the forefront of radio astronomy since the 1940s when scientists at the Commonwealth Scientific and Industrial Research Organisation’s (CSIRO) Radiophysics Laboratory used an antenna perched high on a cliff at Dover Heights in Sydney to make a number of important discoveries.

Since those early days, Australia has become a leader in radio astronomy, building up a suite of world-class facilities including the Australia Telescope Compact Array and the CSIRO Parkes radio telescope and a large and productive astronomy community. On average, each scientific paper produced by the Parkes telescope is more often cited (referred to) than the papers from any other radio telescope in the world.

The Australian Government has now provided $117 million (US$103 million) to help meet some of the key technology and engineering development requirements of the SKA. Australia is also working to offer the best possible location for the SKA. In collaboration with the Western Australian State Government, the Commonwealth Government is establishing a world-leading radio-astronomy observing site in the Mid West Region of Western Australia, as a potential SKA core site.

The significant technological and scientific challenges of the SKA provide an outstanding opportunity to build international science partnerships and high-level skills globally. The SKA will attract some of the world’s best scientists and engineers, and provide major industry opportunities in high technology and other sectors. Destined to become a global icon for science collaboration and endeavour, the SKA will also have a valuable role in promoting the excitement and wonder of science.

Australia and the Square Kilometre Array

Australia Telescope Compact Array, CSIRO

What is the SKA?The SKA will be a revolutionary, next-generation radio telescope capable of transformational science addressing some of the most fundamental unanswered questions in physics and cosmology.

The scale of the telescope is massive and unprecedented. The SKA will digitally combine signals from antennas with a combined collecting area of around one million square metres.

The combination of huge collecting area, versatility and sensitivity will make the SKA the world’s premier imaging and survey telescope over a wide range of radio frequencies, producing the sharpest pictures of the sky of any telescope. It will have up to 50 times the sensitivity and 10,000 times the survey speed of any present radio telescope.

Around half of the array will be located at an extremely radio-quiet core site, with the remaining antennas arranged in clusters which become more sparsely located as they move further from the core site. The SKA will effectively simulate a telescope with a diameter equivalent to the widest separation of antennas, which could be up to 5,000 km in a possible Australasian configuration.

4www.ska.gov.au

For further informationContact: Ms Sara CowanGeneral ManagerSKA TaskforceScience and Research DivisionDepartment of Innovation, Industry, Science and ResourcesGPO BOX 9839Canberra ACT 2601Email: [email protected]

Or visit the Australian SKA project website :www.ska.gov.au

Transformational science with the SKAThe SKA will give the international science community the capacity to study a broad range of fundamental questions in physics and cosmology. The SKA Project Development Office has identified six areas of science where key questions remain unanswered that the SKA will help to address. Of course with an instrument like the SKA, it may turn out that the so far unimagined discoveries are the most important.

SKA Key Science Areas

Evolution of galaxies, cosmology, dark matter and energy

The Cradle of Life – searching for life and planets

Extreme tests of general relativity with pulsars and black holes

Probing the Dark Ages – the first black holes and stars

The origin and evolution of cosmic magnetism

Exploration of the unknown

(Source: SPDO booklet – The SKA – the International Radio Telescope for the 21st Century, 2007).

SKA technology and engineeringBuilding the SKA will require the development of a range of new technologies and new approaches to designing and building telescope elements and integrating systems. Collaboration with industrial partners at the forefront of information and communications technology and high-technology manufacturing will be essential.

Although the physical reality of the SKA is imposing, in many ways it will be a ‘software telescope’ requiring immense data transport and signal processing capacity. The telescope is being designed in a way to take advantage of Moore’s Law for digital hardware: that processing power doubles every 18 months. It is anticipated that by 2020, the processing capacity able to handle the SKA will be available.


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Pulsars discovered and monitored with the SKA will allow us to detect and study gravitational waves - ripples in the fabric of space-time. (Credit: D.Champion, M.Kramer/JBO)

An artist’s impression of a planetary disk forming around a star. Observations with the SKA will contribute to a wide range of goals in the search for life on other planets, from understanding how planets form to searching for more planets. (Credit: M. Kramer/JBO )

Geraldton, Western Australia. Photo: WATC

Perth, Western Australia. Photo: WATC

Visualisation of the SKA. Image: Xilostudios/ISPO

The Australian SKA Pathfinder telescopeA number of SKA ‘pathfinder’ projects around the world are important in the effort to develop technology and engineering solutions to fulfil the ambitions of the SKA. At the leading edge of this effort is the Australian SKA Pathfinder (ASKAP) telescope currently being built by CSIRO with funding from the Australian Government. The enabling technologies for the project are being developed in partnership with institutions in Canada, the Netherlands and South Africa.

ASKAP will comprise up to 45 parabolic dishes. Most of the instrument will be located at the Murchison Radio-astronomy Observatory (MRO) in Western Australia, with a remote station some 3,000 km away in New South Wales, linked via fibre optic cable, which will provide for very-long-baseline observing.

A number of potential SKA technologies will be developed and tested on ASKAP, including phased array receivers and feeds and a ‘green’ power solution for remote site operations. Importantly, ASKAP is being designed and built to be consistent with the SKA Phase 1 reference design as it evolves, ensuring that progress is being made along the critical SKA technology path.

ASKAP will be a significantly more powerful survey instrument than anything built to date. It will be capable of ground-breaking scientific programs in applications such as pulsar astronomy, the study of transient radio sources, cosmology, and the structure and magnetic field of our Galaxy. It is estimated that ASKAP will gather more information in its first six hours of operation than has been saved by the world’s radio telescopes in the last 50 years.

ASKAP is to be operated as part of the CSIRO’s national facilities network and will therefore be available to the international community on a merit basis.

A test antenna for ASKAP is being built at the CSIRO’s observatory at Parkes, New South Wales. Construction of ASKAP itself will start in 2009, with the first science results expected in 2010 and full operation beginning in 2013.

“The region where the MRO is located is characterised by an exceptionally high degree of radio-quietness, low population density and favourable observing conditions.”

The Australian SKA siteIn September 2006 the International SKA Steering Committee announced a shortlist of potential sites for the SKA: Australia and Southern Africa.

The Australian site proposal is for a core site to be established in the remote Murchison Shire in the Mid-West Region of Western Australia, 315km north east of Geraldton. That site is now being developed by the Western Australian Government and the Australian Government, in collaboration with the local community, as a unique radio-quiet observatory to be known as the Murchison Radio-astronomy Observatory (MRO).

The region where the MRO is located is characterised by an exceptionally high degree of radio-quietness, low population density and favourable observing conditions. The pristine condition of the site is being preserved by the exclusion of mining activities and the creation of a 260km radius Mid-West Radio Quiet Zone to limit incompatible radio frequency emissions.

In addition to the MRO site, Australia offers a number of suitable radio-quiet locations for the placement of SKA remote stations. It also offers quality existing infrastructure and a high degree of economic and political stability. Australia generally, and Western Australia particularly, has a long history of successfully undertaking large-scale infrastructure projects, especially in the minerals sector where vast distances and remote locations are common.

Scientific work at the MRO recently began with the establishment of the Early Research Area operated by CSIRO, with infrastructure and equipment to support ongoing site testing and early SKA related experiments. The site is already hosting the Murchison Wide-Field Array experiment (led by the MIT Haystack Observatory), the PAPER experiment (led by the University of California, Berkeley) and the Cosmological Reionization Experiment, or CoRE (led by CSIRO, ATNF).CSIRO Digital Systems Engineer, Dr John O’Sullivan, with a revolutionary detector-

receiver being developed for the ASKAP telescope. Photo: Chris Walsh

The International SKA programInternational collaboration to build a very large radio telescope began around 1994 when the International Astronomical Union established a working group for this purpose. The SKA program is now a major collaboration between institutions in 19 countries. The collaboration is led by the SKA Science and Engineering Committee and a jointly-funded SKA Program Development Office.

Many of the SKA program institutions and agencies are also participating in a study, primarily funded by the European Union Framework Programme 7, to design both the technologies and systems required by the SKA as well as governance and funding options to prepare its construction and operation.

The 19 countries with institutions currently engaged in the SKA program are Argentina, Australia, Brazil, Canada, China, France, Germany, India, Italy, the Netherlands, New Zealand, Poland, Portugal, Russia, South Africa, Spain, Sweden, the United Kingdom and the United States.

An annual International SKA Forum is held to bring together scientists, engineers, public officials, business people and people from the sphere of science education and awareness to promote widespread understanding of the state of the SKA program and the opportunities it provides.

An artist’s visualisation of the ASKAP telescope. Credit: Chris Fluke, Swinburne University of Technology

Pouring concrete for the foundation of the 12m ASKAP test antenna at the Parkes Observatory. Photo Barry Turner

Murchison Radio-astronomy Observatory site in the Mid West Region of Western Australia

Murchison Radio-astronomy Observatory site in the Mid West Region of Western Australia

Australia and the Square Kilometre Array“ASKAP will gather more information in its first six hours of operation than has been saved by the world’s radio telescopes in the last 50 years.”

Australia is playing a significant part in the development of the Square Kilometre Array (SKA), the international radio telescope for the 21st Century.Australia has been at the forefront of radio astronomy since the 1940s when scientists at the Commonwealth Scientific and Industrial Research Organisation’s (CSIRO) Radiophysics Laboratory used an antenna perched high on a cliff at Dover Heights in Sydney to make a number of important discoveries.

Since those early days, Australia has become a leader in radio astronomy, building up a suite of world-class facilities including the Australia Telescope Compact Array and the CSIRO Parkes radio telescope and a large and productive astronomy community. On average, each scientific paper produced by the Parkes telescope is more often cited (referred to) than the papers from any other radio telescope in the world.

The Australian Government has now provided $117 million (US$103 million) to help meet some of the key technology and engineering development requirements of the SKA. Australia is also working to offer the best possible location for the SKA. In collaboration with the Western Australian State Government, the Commonwealth Government is establishing a world-leading radio-astronomy observing site in the Mid West Region of Western Australia, as a potential SKA core site.

The significant technological and scientific challenges of the SKA provide an outstanding opportunity to build international science partnerships and high-level skills globally. The SKA will attract some of the world’s best scientists and engineers, and provide major industry opportunities in high technology and other sectors. Destined to become a global icon for science collaboration and endeavour, the SKA will also have a valuable role in promoting the excitement and wonder of science.

Australia and the Square Kilometre Array

Australia Telescope Compact Array, CSIRO

What is the SKA?The SKA will be a revolutionary, next-generation radio telescope capable of transformational science addressing some of the most fundamental unanswered questions in physics and cosmology.

The scale of the telescope is massive and unprecedented. The SKA will digitally combine signals from antennas with a combined collecting area of around one million square metres.

The combination of huge collecting area, versatility and sensitivity will make the SKA the world’s premier imaging and survey telescope over a wide range of radio frequencies, producing the sharpest pictures of the sky of any telescope. It will have up to 50 times the sensitivity and 10,000 times the survey speed of any present radio telescope.

Around half of the array will be located at an extremely radio-quiet core site, with the remaining antennas arranged in clusters which become more sparsely located as they move further from the core site. The SKA will effectively simulate a telescope with a diameter equivalent to the widest separation of antennas, which could be up to 5,000 km in a possible Australasian configuration.

4www.ska.gov.au

For further informationContact: Ms Sara CowanGeneral ManagerSKA TaskforceScience and Research DivisionDepartment of Innovation, Industry, Science and ResourcesGPO BOX 9839Canberra ACT 2601Email: [email protected]


Transformational science with the SKAThe SKA will give the international science community the capacity to study a broad range of fundamental questions in physics and cosmology. The SKA Project Development Office has identified six areas of science where key questions remain unanswered that the SKA will help to address. Of course with an instrument like the SKA, it may turn out that the so far unimagined discoveries are the most important.

SKA Key Science Areas

Evolution of galaxies, cosmology, dark matter and energy

The Cradle of Life – searching for life and planets

Extreme tests of general relativity with pulsars and black holes

Probing the Dark Ages – the first black holes and stars

The origin and evolution of cosmic magnetism

Exploration of the unknown


SKA technology and engineeringBuilding the SKA will require the development of a range of new technologies and new approaches to designing and building telescope elements and integrating systems. Collaboration with industrial partners at the forefront of information and communications technology and high-technology manufacturing will be essential.

Although the physical reality of the SKA is imposing, in many ways it will be a ‘software telescope’ requiring immense data transport and signal processing capacity. The telescope is being designed in a way to take advantage of Moore’s Law for digital hardware: that processing power doubles every 18 months. It is anticipated that by 2020, the processing capacity able to handle the SKA will be available.


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Pulsars discovered and monitored with the SKA will allow us to detect and study gravitational waves - ripples in the fabric of space-time. (Credit: D.Champion, M.Kramer/JBO)

An artist’s impression of a planetary disk forming around a star. Observations with the SKA will contribute to a wide range of goals in the search for life on other planets, from understanding how planets form to searching for more planets. (Credit: M. Kramer/JBO )

Geraldton, Western Australia. Photo: WATC

Perth, Western Australia. Photo: WATC

Visualisation of the SKA. Image: Xilostudios/ISPO

Fact sheet

The SKA will require new technology and progress in fundamental engineering in fields such as information and communication technology, high performance computing and production manufacturing techniques. It will comprise a vast array of antennas, arranged in clusters to be spread over 3000 kilometres. The antennas will be linked electronically to form one enormous telescope. The combination of unprecedented collecting area, versatility and sensitivity will make the SKA the world’s premier imaging and survey telescope over a wide range of radio frequencies, producing the sharpest pictures of the sky of any telescope.

The SKA will:be the next-generation radio telescope for the international scientific community

revolutionise our understanding of the Universe by providing answers to questions about its complexity and the fundamental laws of physics

have up to one square kilometre of effective collecting area and be the largest telescope in the world

have up to 50 times the sensitivity and 10,000 times the survey speed of present radio telescopes

use new technology antennas, signal transport, signal processing and computing provided by innovations in radio frequency and information communication technology

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Why build the SKA?In order to answer some fundamental questions about the origin and evolution of the Universe, a more sensitive radio telescope is needed that can detect the very weak signals coming from the edge of the cosmos. A telescope such as the SKA will be able to ‘see’ distant objects in the very young Universe and provide answers to questions such as the emergence of the first stars, galaxies and other structures. Because the speed of light is finite and the size of the Universe is so large, telescopes are effectively time machines, enabling astronomers to look into the past and study the Universe as it was billions of years ago.

What is the SKA?The Square Kilometre Array (SKA) is a next-generation radio telescope that will be up to 50 times more sensitive than the best present-day instruments. It will give astronomers remarkable insights into the formation of the early Universe, including the emergence of the first stars, galaxies and other structures. This will shed light on the birth, and eventual death, of the cosmos.

Fact sheet

Artist’s impression of SKA antennas. Credit: skatelescope.org

Five key science projects have been identified for the SKA, namely:

Extreme tests of general relativity from the study of pulsars and black holes.

Evolution of galaxies, cosmology, dark matter and energy.

Probing the Dark Ages – the first black holes and stars.

The Cradle of Life – searching for life and planets.

The origin and evolution of cosmic magnetism.

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Who is involved in the project?The SKA is a collaboration between institutions in 17 countries (including Australia and countries in Europe, Asia, Africa, and North and South America), led by an international science and engineering committee and a jointly-funded SKA Project Office. The cost of the telescope (about A$1.8 billion) will be shared by the participating countries. Scientists are also collaborating with industry partners to develop the necessary technologies to design and build the telescope.

Where will the SKA be built?In December 2005 four countries (Australia, Argentina, China and South Africa) submitted proposals to the International SKA Steering Committee (ISSC) to host the SKA. On September 28, 2006 it was announced that Australia and Southern Africa had been short-listed as acceptable sites to host the SKA – the final decision will be made around 2011-12.

The Australian candidate site is in Mid West of Western Australia, within the Shire of Murchison. This region is one of the few places in the world today that is suitable in terms of its radio-quietness and its radio-astronomy observational qualities.

What will the SKA look like?It is proposed that the SKA will have an inner core, comprising a set of ‘flat phased arrays’ surrounded by several hundred dish-shaped antennas.

Two different kinds of antenna at the core are necessary to enable the telescope to receive a wider frequency range and to enable wide fields-of-view at low frequencies. In addition to this core site, a series of remote array-stations (clusters of dishes) forming a five-arm spiral configuration will be built. The addition of the remote stations means that the signals from the separate antennas can be digitally combined to simulate a single telescope with a diameter equal to the distance separating the two furthest antennas. Since the Australian proposal provides for array-stations to potentially be sited as far away as New Zealand, this could be more than 5000 km.

Computing The telescope’s computing and communications systems will need to cope with very high data transport rates. In the inner array the data will be transported to a central processor at the rate of 80 Gigabytes per second per antenna, while long haul links servicing the outer and remote array-stations may need a capacity of 2 Terabytes per second per station. This is more than the current total internet traffic in Europe!

4www.ska.gov.au

For further informationContact: Diana LondishCSIRO Australia Telescope National Facility email: [email protected]

Or visit the International SKA website:www.skatelescope.org

Or visit the Australian SKA project website:www.ska.gov.au

View over part of the proposed SKA candidate site in WA. Photo credit: Dave DeBoer

Schematic view of the proposed SKA configuration. Credit: skatelescope.org

Fact sheet

Astronomers use both light and radio waves to learn about the objects in space that emit them. Information, including the size, shape and composition of objects can be ascertained from their radio or light emissions. Radio waves can penetrate through cosmic dust allowing astronomers to look into regions, such as the centre of our galaxy, the Milky Way, which is obscured by dust at optical wavelengths.

What are Radio Waves?Radio waves are a form of electromagnetic radiation, as are light waves. Since wavelength and frequency are inversely related, lower frequency means longer wavelength. Radio waves are low frequency waves and thus have a greater wavelength than light waves. In fact light waves have wavelengths measured in hundreds of nanometers, while radio waves are measured in up to tens of metres. Low frequency also means low energy, so radio waves have less energy than light waves as well.

Since radio waves can penetrate through dust and different cosmic objects radiate most strongly at different frequencies, something which cannot be seen with an optical telescope can often be ‘seen’ with a radio telescope.

The longer wavelength of radio waves means radio telescopes need to be much larger than optical telescopes to generate high resolution images. Radio telescopes are some of the largest scientific instruments in the world.

What is Radio Astronomy?Radio astronomy, like optical astronomy, examines the electromagnetic radiation from objects outside the earth’s atmosphere – stars, galaxies and other cosmic objects. Where optical telescopes gather light, radio telescopes gather radio waves.

long wavelengthlow frequencylow energy

shorter wavelengthhigher frequencyhigher energy

wavelength, λ

wavelength, λ

Electromagnetic Waves

Fact sheet

CSIRO Australia Telescope Compact Array, Narrabri, NSW

Radio TelescopesRadio telescopes are very sensitive devices that measure the intensity of radio waves over a band of frequencies. Their antennas are often in the shape of a ‘dish’ or cylindrical reflector to provide a large collecting area. The radio waves are reflected off the collector surface and are focused onto a receiver. Australia’s largest single dish radio telescope is the CSIRO Parkes Radio Telescope, also known as ‘The Dish’. The information, once collected, is then electronically amplified and processed so that it can be measured by a computer and interpreted by astronomers.

When two (or more) signals are combined from separate antennas the telescope is known as an interferometer. Signals from an interferometer can be electronically combined to simulate a single dish of a size equal to the largest antenna separation – the bigger the separation, the better the resolution of the image that can be produced. The sensitivity of an interferometer increases as the total amount of collecting area increases. This is one reason why the Square Kilometre Array will be such a powerful radio telescope.

Where are Radio Telescopes Sited?Because they are so sensitive to radio emissions, radio telescopes are highly susceptible to interference from modern-day radio-communication services and emissions from other electrical equipment. To minimise such interference radio astronomy antennas are usually placed in remote locations where there is a low population density.

4www.ska.gov.au

For further informationContact: Diana LondishCSIRO Australia Telescope National Facility email: [email protected]


History of Radio Astronomy The first radio astronomy observations were made in 1932 by the USA Bell Laboratories physicist Karl Jansky. He detected cosmic radio noise from the centre of the Milky Way galaxy while he was investigating radio disturbances to a trans-oceanic telephone service. Then, with the development of radar in the Second World War, improvements to antennas and electronics were made. This meant that after the war, scientists could start to investigate radio signals coming from space.

Australia’s Role in Radio AstronomyAustralia has been at the forefront of radio astronomy since the early days with scientists at CSIRO’s Radiophysics Laboratory using an antenna perched high on a cliff at Dover Heights in Sydney to make many important discoveries. Since then Australia has developed a strong tradition of excellence in radio astronomy and is acknowledged as a world leader in this field.

The CSIRO’s Australia Telescope Compact Array (ATCA), Paul Wild Observatory near Narrabri NSW. Photo credit: Michael Dahlem

CSIRO Parkes radio telescope (aka ‘The Dish’), NSW, Australia

australia and the square kilometre array

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