The first of three Antarctic survey telescopes has been successfully installed at one of the coldest and most remote places on Earth - at the highest point of the Antarctic Plateau.
The remotely controlled telescope at China’s Kunlun Station at Dome A, Antarctica, will be used to search for planets beyond the solar system, by continuously monitoring hundreds of millions of stars in our own Milky Way Galaxy. The telescope is equipped with a 110-megapixel CCD camera, the largest single-piece detector in use in astronomy today.
The multi-national team that built the telescope includes the Chinese Center for Antarctic Astronomy, the University of New South Wales, and Texas A&M University. PLATO-A, the onsite laboratory that harbors the power supply and control computers was designed and built by a team of astronomers at UNSW. The UNSW team monitors and operates the power and computing systems remotely from Sydney, and the telescope is operated from China.
“This is an astounding achievement,” says Professor Michael Ashley, the astrophysicist who heads the UNSW team responsible for PLATO-A.
“A stand-alone telescope in the pristine environment of Antarctica can conduct scientific research that would otherwise only be possible from space, but at a small fraction of the cost.”
Four astronomers installed the telescope as part of China’s 28th Antarctica Expedition, led by the Polar Research Institute of China.
A 26-member team sailed late last year from Tianjin, China, aboard the icebreaker Xuelong to the Chinese Zhongshan Station on the Antarctic coast. They arrived at Dome A on 4 January after a 19-day traverse that took them 1,200 kilometres inland and climbing almost 4,000 metres in altitude. The telescope took 20 days to install before the team returned to Zhongshan Station on 9 February.
“The observatory has to withstand the most extreme conditions on Earth,” says Professor Xiangqun Cui, of Nanjing Institute of Astronomical Optics Technology. “The winter temperature can be as low as minus 80 C, and the air pressure is barely half of that sea level. It has to be able to prevent ice from building up on mirror surfaces and the telescope support structure.”
The entire observatory – known as AST3-1 - is operated autonomously and is fully steerable, meaning it can be pointed to any sky area visible from Dome A. It has an on-site computing system to analyse in real time the massive amount of data from the CCD camera. It will be able to catch transient events such as Type 1a supernova explosions within a day of them become visible.
The telescope can also be used for observations of the optical afterglows of gamma-ray bursts. Professor Zhaohui Shang of the National Astronomical Observatory of China and Tianjin Normal University notes that the data from each exposure can be processed within two minutes, to promptly alert the science team when a new supernova occurs.
Four years ago, the same team successfully installed the first PLATO observatory. Data collected there has confirmed that Dome A - with its cold temperature, dry air, and stable atmosphere- is likely the best site on Earth for establishing astronomical observatories.
“The ability to monitor stars during the dark austral winter makes AST3-1 a unique facility for astronomy,” says Professor Lifan Wang, the director of the Chinese Center for Antarctic Astronomy, and a Professor at Texas A&M University.