Physical Society Colloquium

The Fermi Gamma-ray Space Telescope: The First 3 Months

Peter Michelson

Kavli Institute of Particle Astrophysics and Cosmology and Department of Physics
Stanford University

The Fermi Gamma-ray Space Telescope (formerly GLAST) was launched by NASA on June 11, 2008. The Large Area Telescope (LAT) instrument measures cosmic gamma-ray radiation in the energy range 20 MeV to >300 GeV, with measurements by the GLAST Burst Monitor (GBM) of gamma-ray bursts from 8 keV to 30 MeV. The LAT, with a large improvement in sensitivity, large field-of-view, and much finer angular resolution compared to previous high-energy telescopes, observes 20% of the sky at any instant and covers the entire sky every 3 hours. Fermi is providing an important window on a wide variety of high-energy phenomena, including pulsars, black holes and active galactic nuclei; gamma-ray bursts; the origin of cosmic rays and supernova remnants; and searches for new phenomena such as supersymmetric dark-matter annihilations and exotic relics from the Big Bang. I will describe the Fermi observatory and provide an overview of the observations made to date.