The Multi-Aperture Scintillation Sensor installed in the UNSW AASTINO facility at Dome C, Antarctica.

How can we measure the turbulence in the Antarctic atmosphere at an altitude of between one and 20 kilometres?” This turns out to be a crucial question when deciding where to build the new generation of Extremely Large Telescopes (ELTs).

A group of us were huddled around a table pondering this question at the 25th General Assembly of the International Astronomical Union meeting held in Sydney during July 2003. The group included colleagues from the Cerro Tololo Inter-American Observatory (CTIO), Caltech, and the Jet Propulsion Laboratory (JPL). We hatched an ambitious plan to build a suitable instrument to make the crucial measurement.

The instrument had to be able to work in an environment where the ambient temperature reaches -75C. It had to locate bright stars and measure them without any human intervention for 10 months. It had to be aligned in bright sunshine during the Antarctic summer. It had to work completely automatically and transmit data back to UNSW using an Iridium satellite phone.

And it had to be designed, built, and shipped to Antarctica before the end of the year.

Our colleagues from CTIO built the detector package, JPL provided some funding, and UNSW designed and built the telescope, CCD acquisition camera, star-tracking mount, and computer control.
The instrument, called MASS (Multi-Aperture Scintillation Sensor), started to come together in November. With two weeks to go before shipping, we desperately needed one or two clear nights to test the instrument on the roof of the Physics building. The clouds cooperated between Christmas and New Year, on the day before we had to ship.

MASS was installed by Jon Lawrence, Tony Travouillon and Colin Bonner at Dome C in Antarctica in January 2004. We are now waiting for the sun to set...(stop press 18 March 2004: MASS has seen its first star!).

Michael Ashley, Jon Lawrence,
Suzanne Kenyon and John Storey