[LINK] The Square Kilometre Array

[stephen at melbpc.org.au]

Australia’s bid for the Square Kilometre Array – an insider’s perspective

By Lisa Harvey-Smith Square Kilometre Array (SKA) Project Scientist CSIRO
1st February 2012


Australia and New Zealand could be on the brink of a major scientific 
coup. 

In roughly a month’s time, the site for the Square Kilometre Array (SKA) 
radio telescope will be announced.

Australia and New Zealand are competing against a consortium of nine 
African countries – led by South Africa – for the right to host this A$2 
billion mega-science project – one of the largest and most ambitious 
scientific projects ever conceived.

Last year, representatives from Australia-New Zealand prepared a detailed 
submission to assist the SKA Site Advisory Committee with its 
deliberations. I was lucky enough to be a part of that team.

The document, which exceeded 1,000 pages and included input from more 
than 40 organisations and agencies, provided data in sometimes eye-
watering detail on the physical and environmental characteristics of our 
candidate site. It also described the social, political and legal 
structures relevant to administering the project in Australia and New 
Zealand. For several weeks, submissions from both candidate sites were 
scrutinised by an international panel of experts. 

Very shortly, in the next few weeks, the committee will deliver its 
recommendation of the preferred site to the SKA Board of Directors. The 
board will then have the final responsibility for choosing a site. This 
decision is expected to be announced in mid- to late-March.

The level of anticipation within the scientific community is palpable. 

Astronomers, engineers and officials are collectively holding their 
breath, awaiting the announcement.

I have witnessed a remarkable level of enthusiasm from the general 
public. At an ABC “meet a scientist” event last year I asked a young 
girl – of around 11 years old – if she knew what a radio telescope was. 
Her reply stunned me: “Is that like the SKA?”, she asked, before 
proceeding to tell me there was competition between Australia and South 
Africa to host the telescope.

So what makes the ideal site for the world’s most sensitive radio 
telescope?

The primary consideration is, unsurprisingly, the suitability of the 
location for radio astronomy. With the rapid expansion of electronic 
communications devices such as mobile phones, radio astronomers around 
the world have experienced a large negative impact from the encroachment 
of stray “radio frequency interference” into their telescope receiver 
systems.

This can be extremely damaging to science output and costly to mitigate. 
CSIRO’s existing observatories in rural New South Wales – such as the 
Parkes Observatory – are increasingly suffering from population growth 
and the associated radio interference. The problem will be much more 
acute for the SKA, which will be more sensitive and observe over a very 
large frequency range, in order to pick up signals from the distant 
universe.

To avoid such man-made interference, CSIRO, working with WA State and 
Federal Governments, has established the Murchison Radio-Astronomy 
Observatory in one of the most remote areas of Western Australia.

By way of contrast, the region within 100km of CSIRO’s Paul Wild 
Observatory near Narrabri, NSW, has a population density of one person 
per square kilometre. Within 100km of our candidate SKA site, the figure 
is 100 times lower.

In order to protect this extraordinarily radio-quiet region, CSIRO and 
government agencies have negotiated a strong legal framework to protect 
the Murchison Radio-Astronomy Observatory for generations to come.

The SKA will comprise a number of different receiver systems, which will 
enable observations over a large frequency range. There are strong 
scientific advantages of placing these systems at a single, high-quality 
site:

•the infrastructure cost is shared between the high- and low-frequency 
receivers, increasing the available budget for the (scientifically 
productive) hardware and active components of the telescope
•the scientific return of a geographically distributed telescope is 
diminished because simultaneous observations of the sky over a large 
frequency range would be impossible
•if man-made interference were greater at one location, it would 
inevitably diminish the science return to place any antennas on the site 
more afflicted by radio interference.
For these reasons, I have no doubt that the merit-based process to 
identify a single site for the telescope is the correct approach. Given 
the SKA will inhabit one of the last remaining radio-quiet sites on 
Earth, the quality of science is not an area in which we can afford to 
compromise.

I have heard the SKA site bid compared to an Olympic bid, but in many 
ways that understates the significance of the project. A successful SKA 
telescope will provide a massive boost for science worldwide, together 
with the spin-off benefits that flow from such internationally focused 
innovative technology projects.

This will happen, provided the very best site is chosen to enable maximum 
potential for scientific discovery and maximum engagement from the global 
technology community.

Australia and New Zealand have incredibly strong credentials to support 
the SKA on behalf of the whole world for the 50-year lifetime of the 
instrument. I hope in 2012 – an Olympic year – we ensure scientific 
excellence emerges from this process victorious.

<http://theconversation.edu.au/australias-bid-for-the-square-kilometre-
array-an-insiders-perspective-4891>
--

Cheers,
Stephen