Progress Of Antarctic Schmidt Telescopes (Ast3) For Dome A

Prelimenary site testing led by Chinese Center of Antarctic Astronomy (CCAA) shows that the highest point of the Antarctic Plateau Dome A has very clear sky, good seeing, slow wind, low boundary layer and very low precipitable water vapour which make it the best site on earth for optical/IR and sub-mm observations. Chinese Small Telescope ARray (CSTAR) was installed at Dome A in 2008 and have automatically observed for about 3 antarctic winters. The three Antarctic Schmidt telescopes(AST3) with entrance pupil diameter 500mm are the second antarctic project proposed by CCAA and the first AST are being constructed in NIAOT now which is planned to be mounted on Dome A at the beginning of 2011. All the tracking components were tested in the low temperature chamber and an adaptive defrosting method is designed to prevent the frost building up on the schmidt plate.