Powerful Australia Telescope Begins Probing the Southern Skies

Reuters | 31 August 1990


By Wilson da Silva


SYDNEY: Big science has reached outback Australia. Amid the cotton fields of northern New South Wales is a US$48.4 million radio telescope that scientists say is the most powerful astronomical tool in the southern hemisphere.

“This is an extremely important instrument,” said Dr Hector Alvarez of the University of Chile, one of a group of International Astronomical Union scientists who visited the facility at Culgoora in July. "All of us are expecting major discoveries to be made."

Known as the Australia Telescope, the array of five dishes went into operation in April and immediately produced results. “In scientific terms we were pleased, but in reality we are fairly ecstatic,” said Dr Lister Staveley-Smith, an astronomer with Australia Telescope. “On its first operation the results were very nice.” The telescope yielded clear pictures of a rare, faraway scene – the dead shell of an exploded star about 1,000 years old.

When joined with the Parkes Radiotelescope further south, the array will become a giant 'radio eye' 320 km wide. Astronomers say it will give them radio images of unprecedented detail.

​Commissioned in 1988, the Australia Telescope has five dishes, each weighing 270 tonnes, which sit atop three kilometres of rail track. Together they act as a single telescope, reaching deep into the southern sky. By September next year the facility expects another dish, also 22 metres wide, to be wired into the network and a year later a seventh dish near Coonabarabran, 115 km to the south, should be operational.

When joined with the Parkes Radiotelescope further south, the array will become a giant 'radio eye' 320 km wide. Astronomers say it will give them radio images of unprecedented detail.

“This is a whole new field and there isn’t an instrument like it anywhere in the world,” said Australia Telescope manager Dr Graham Nelson. “There are plenty of things waiting to be discovered.” For specialised studies there are plans to link up with dishes in Perth in western Australia, Hobart on the southern island of Tasmania and Alice Springs in the centre of the continent.

The array will be linked to the Soviet radio telescope satellite RadioAstron when it is launched in 1992. At its widest orbit the satellite and link-up will produce a 'radio eye' five times the size of the Earth. The telescope’s first coup was a supernova astronomers have labelled SNR 0540-693. It is only the second known supernova cloud emitting radio signals which are activated by a spinning star known as a pulsar.

At its widest orbit the satellite and link-up will produce a 'radio eye' five times the size of the Earth.

Other targets for the array will be sun-gobbling monsters which emit energy equal to 100 billion stars, the dead husks of old stars, the birth of suns, and the southern sky’s Magellanic Clouds – at 170,000 light years away the nearest galaxy to ours.

Its competitor is the Very Large Array (VLA) of 27 dishes in the New Mexico desert of the United States, completed in 1980. Astronomers say the Australia’s six dishes, because of advances in technology, equal the sensitivity of the U.S. instrument.

Dr Ron Ekers was director of the VLA until 1987, when he was lured home to run the Australia Telescope. “The attraction of the instrument is that it’s in the southern hemisphere, where a lot of work remains to be done [in radio astronomy]. No one’s had this capability until now,” he said.

“Australia has a reputation in radio astronomy out of all proportion to its economic power,” said Dr Thijs de Graauw of Netherlands’ Laboratory for Space Research, a recent visitor to the telescope. “It is well respected, and this instrument will be very popular. It is big science, and a lot of the activity nowadays is in the southern hemisphere. Astronomers are looking forward to getting time on the instrument. I know I will.”

Wilson da Silva is a foreign correspondent for Reuters in Sydney, Australia.

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