Antarctic astronomy - its potential importance for research into the interstellar medium

Abstract

Site conditions at the South Pole have been shown to be exceptionally favourable for infrared astronomy. The sky brightness between 2.3 and 14 um is typically between 20 and 100 times lower than at temperate sites, and the mid-infrared sky stability is extraordinarily good. Furthermore it appears that almost all of the seeing degradation is confined to the lowest 100 metres of the atmosphere where it can readily be corrected with low-order adaptive optics. It is probable that conditions at Dome A and Dome C, higher on the Antarctic plateau, are even better. Because of these very unusual conditions even a modest-sized telescope can, at some wave-lengths, achieve better sensitivity levels than any other ground-based facility. We propose the construction of SPIRIT, the South Pole InfraRed Imaging Telescope, a 2.5 metre class, wide-field, IR-optimised telescope. Particular areas in which SPIRIT will be able to make important contributions include population studies of star formation regions at 3.5um, molecular hydrogen observations at 2.4um, PAH studies at 3.3um and searches for protostars in the mid infrared. The challenges of working in Antarctica will be described as well as the efforts currently underway to obtain comprehensive data on site conditions across the plateau.