A team of Australian researchers has built an unmanned observatory high on an Antarctic plateau that may provide images nearly the equal of Hubble’s. That’s the word from Nature, where University of New South Wales associate professor Michael Ashley, co-author of the paper, described the capabilities of the new viewing site. The paper’s lead author is Dr. Jon S. Lawrence, a postdoctoral fellow at the University of New South Wales.
The location is known as Dome C, 3250 meters above sea level on the Antarctic Plateau, at latitude 75 degrees south. Among its favorable characteristics are low infrared sky emission, dry and extremely cold air, few clouds and low dust and aerosol content. The upshot: much less ‘star jitter.’ All of these factors make the site, which is 400 meters higher than the South Pole, far better for viewing than the location of instruments currently in place in Chile, Hawaii and the Canary Islands.
Having established the superiority of Dome C, the team now argues for larger apertures at the site that could deliver Hubble-style images at a cost far below that of much larger Earth-bound telescopes. “The discovery means that a telescope at Dome C on the Antarctic plateau could compete with a telescope two to three times larger at the best mid-latitude observatories, with major cost-saving implications,” Ashley said. “Dome C could become an important ‘test-bed’ for experiments and technologies that will later be flown as space missions. Indeed, for some projects, the site might be an attractive alternative to space based astronomy.”
At the site currently is an automated station called AASTINO (Automated Site Testing International Laboratory), which the duo established in January of 2004. The entire experiment was subsequently run by remote control. “When we left there in February,” said Ashley, “we said goodbye to it knowing all that we could do was communicate with it by the phone and the Internet. If we’d needed to press a reset button on a computer or something, there was no way to do so, and the entire experiment could have failed.” A news release from the University of New South Wales provides more information.
What may come next at Dome C makes for fascinating conjecture. At the SPIE Astronomical Telescopes and Instrumentation conference last June in Glasgow, Dr. Will Saunders of the Anglo-Australian Observatory presented a telescope concept built around icecrete — compressed snow in blocks as hard as concrete — that could be built at the site. According to Saunders, as quoted in this press release from the Anglo-Australian Observatory in Sydney: “With this simple telescope you could do the exquisite imaging that the extremely large telescopes plan to do, at a fraction of their cost. But, unlike them, this telescope would also be a great survey instrument, able to map the whole sky with Hubble-like clarity.”
All this at a fifth of the price of some of the large Earth-bound instruments now in planning stages. The Nature article is Jon S. Lawrence, Michael C. B. Ashley et.al., “Exceptional Astronomical Seeing Conditions Above Dome C in Antarctica.” Nature 431, pp. 278-81 (16 September 2004). Nature‘s online news site has a precis.
