Antarctic Astronomy

Michael Ashley preparing to install a fibre optic cable on the GMOUNT telescope at the US South Pole Station, during February 2001. Latitude -90S, temperature -37C.

The summer of 2000/01 saw the installation of two new instruments in Antarctica for measuring the characteristics of the site for a future large telescope. Both instruments were built in the School of Physics, and both were deployed at Dome C, a remote location on the high antarctic plateau where France and Italy are establishing a scientific station.

The antarctic plateau is the best observing site on the earth's surface for infrared and sub-millimetre astronomy. This arises from the exceptionally cold and dry environment, as well as the high altitude of the plateau. Most people have a mental image of Antarctica that includes severe winds and blizzards, but this does not apply to the high plateau regions - at Dome C the wind averages just 2 metres/second.

One of the instruments we installed at Dome C is called ICECAM, a low-power CCD camera that takes images of the sky every two hours for a year. The images are stored in solid-state memory for later retrieval and analysis. ICECAM also controls an ARGOS satellite transmitter that is able to return summaries of the data back to UNSW. Most of the ICECAM experiment is buried in a ``crypt'' 7 metres below the ice level at Dome C. At this depth the temperature is immune from annual flucuations, and so remains at a constant -50C, thereby avoiding the extremes of -80C found on the surface.

The other experiment is SUMMIT, a sub-millimetre atmospheric emission monitor. This was installed at Dome C in November 2000 by Prof. John Storey and Paolo Calisse, a UNSW graduate student. Paolo went on to spend three months at Dome C running SUMMIT, before moving the instrument to the US South Pole station, where it will collect data throughout 2001.