The ROTSE-III telescope.	The apocalyptic moment two billion light years away when the giant star exploded.

On 26 March 2003, after two years of work, the School of Physics completed the commissioning of its ROTSE-III telescope at Siding Spring Observatory. The telescope is designed to study the visible light emitted during the formation of black holes.

Some 2 billion years earlier, a star with a mass about 50 times that of our sun reached the end of its life and imploded, producing a black hole. This event released more energy in one second than the Sun does during its entire 9 billion year life.

On 29 March 2003, gamma-rays from the violent birth of this black hole reached our solar system and were detected by an earth-orbiting satellite. A signal from the satellite was sent to our ROTSE-III telescope, and the telescope automatically moved to the position of the star and took an image. The image showed an explosion one hundred times brighter than any previously observed event. Three days later our ROTSE-III image was on the front page of the Sydney Morning Herald.

ROTSE-III has since responded to three other gamma-ray alerts, although none as impressive as that of 29 March 2003 — estimated to be a once in a decade event. Of the dozen competing robotic telescope experiments around the world, ROTSE-III’s ability to take an image within 10 seconds of the event is unique. This is a crucial time period in which to understand the formation of a black hole and its interaction with the surrounding matter.

We are now eagerly awaiting the launch of the SWIFT satellite in late 2004. SWIFT will provide a rich source of gamma-ray alerts for ROTSE-III.

Our experiment is in collaboration with the University of Michigan, Los Alamos National Laboratories, and Lawrence Livermore National Laboratory.

Michael Ashley and Andre Phillips