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Australian scientists have claimed a major breakthrough in the development of a new telescope technology that has the potential to revolutionize astronomy.
An image of distant galaxies taken last week by the Australia SKA Pathfinder (ASKAP) radio telescope in western Australia represented a huge step forward in the field, according to the Commonwealth Scientific and Industrial Research Organization ( CSIRO), the Australian federal body that is developing the technology.
When fully developed the technology would outperform conventional telescopes in several areas, enabling telescopes to survey larger areas of the sky and make clearer images much more speedily.
Professor Brian Boyle, the director of the Australian SKA project, even went so far as to say "the future of radio astronomy has arrived."
ASKAP is developing technologies for the international Square Kilometer Array (SKA) telescope that will be built in Australia and South Africa from 2018.
The image taken last week has delighted scientists around the world because it signals ASKAP is working as a fully fledged radio telescope after just a few months of commissioning.
Dr. Lewis Ball, chief of CSIRO astronomy and space science, is leading a delegation of scientists and engineers presenting the results in Europe.
"These ASKAP results are generating great excitement," Ball said, "because they clearly demonstrate the revolutionary potential of CSIRO's new phased array feed technology."
Dr. David McConnell, who leads the ASKAP commissioning and early science team (ACES), said ASKAP was functioning properly as an aperture-synthesis telescope.
"We've never had a telescope like this before," he said. "We can see that the novel aspects of its design really do work, and that it will outperform a conventional telescope."
The image taken last week, of a region of sky near the south celestial pole, is the equivalent of a black and white photo, but made from radio waves.
The image covers 10 square degrees on the sky -- about 50 times larger than the full Moon -- and was made from nine overlapping regions, or beams, captured simultaneously.
The quality of the image vindicates ASKAP's two novel features: phased array feeds -- new technology developed by CSIRO -- and a special axis of rotation on each antenna.
The phased array feeds act as radio cameras, allowing the telescope to see large areas of sky at once.
"This image shows that the phased array feeds are stable over the 12 hours it takes to make an observation like this," McConnell said.
"Now we can start to use the other advantages of phased array feeds, such as changing the beam size and shape for particular kinds of observations."
As the telescope tracks radio sources, the phased array feed is kept in a fixed orientation to the sky, thanks to a special axis of rotation built into each ASKAP antenna.
"With a conventional telescope we would have expected artefacts from bright sources at the edges of each beam," McConnell said.
"With ASKAP we don't get that because the phased array feed is held at a constant angle to the stars."
The dynamic range of the image was 50,000:1, which would have been a good result from a mature telescope, let alone one in commissioning.
Even at this early stage, ASKAP was able to make the new image twice as fast as any comparable telescope in the southern hemisphere.
When completed, ASKAP will be able to survey the sky 25 times faster still, and will be the world's premier survey telescope for centimeter-wavelength radio astronomy.
Procurement is now under way for even better second generation phased array feeds.
