Glast will be used to observe the extreme universe where electrons and nuclear particles are accelerated to ultra high energies not attainable on earth, where enormous explosions of mysterious origin light up the cosmos in high-energy gamma rays on a daily basis, and where dark matter and dark energy dominate.

Glast, an acronym for Gamma ray Large Area Space Telescope, is scheduled for a 2005 launch date. Glast will be built and used by a unique international collaboration of Astrophysicists and Particle Physicists.

The management of the project will be centered at the Stanford Linear Accelerator Center (SLAC). SLAC, an arm of Stanford University, is funded by the Department of Energy.

Stanford Physics Professor Peter Michelson, the principal investigator for the project, said, "The Glast collaboration has participation from more than 20 institutions from 6 countries. SLAC has been a world leader in particle physics experiments and has nurtured much successful international collaboration.

"We have assembled an international team with all the expertise to build the telescope. Glast will enable the study of many important cosmological mysteries where particle physics has fundamental relevance, including the mechanisms of cosmic particle acceleration, the physics driving the mysterious gamma ray bursts, and the nature of dark matter," added Michelson.

Glast is expected to have a mission life of five years after launch.

Glast will make great improvements over the performance of high-energy telescopes, such as EGRET, currently aboard the Compton Observatory. EGRET has operated successfully, long past its design life, and is about to stop.

Relative to EGRET, Glast will have a field of view and an effective area each about 6 times larger, sensitivity more than 50 times better, and energy reach extending more than 10 times higher.

Its wide field of view will enable scientists to probe extreme transient phenomena such as active galactic nuclei and the mysterious gamma ray bursts over a wide range of timescales.

The primary instrument of Glast is a matrix of towers composed of thin lead foil interleaved with thin silicon detectors to record the gamma-ray direction, followed by a matrix of scintillation crystals to measure the gamma ray energy.

Using about 100 square meters of silicon strip detectors Glast will be by far the largest silicon based detector to be launched into space.

"We're delighted with this new partnership between the Department of Energy (which funds SLAC) and NASA," said SLAC Director Jonathan Dorfan.

"With our experience in large scale international projects and our expertise in detector technology, and NASA's experience in space science, we know we have a winning team," added Dorfan.