Skip to main content Skip to secondary navigation


Main content start
Fermi Instruments (LAT and GBM)
The Large Area Telescope and the Gamma-ray Burst Monitor

Fermi Instruments

The Large Area Telescope (LAT) is the principal scientific instrument on the Fermi Gamma Ray Space Telescope spacecraft. Originally called the Gamma-Ray Large Area Space Telescope (GLAST), the mission was renamed for the physicist Enrico Fermi. Fermi carries two instruments, one is the LAT and the other one is the Gamma-ray Burst Monitor (GBM). The LAT is Fermi's primary instrument, and the GBM is the complementary instrument. The Fermi spacecraft was launched into a near-earth orbit on 11 June 2008. The Fermi LAT instrument collaboration is an international effort, funded by agencies in several countries [*].

The LAT is an imaging high-energy gamma-ray telescope covering the energy range from about 20 MeV to more than 300 GeV. Such gamma rays are emitted only in the most extreme conditions, by particles moving very nearly at the speed of light. The LAT's field of view covers about 20% of the sky at any time, and it scans continuously, covering the whole sky every three hours.

Currently the LAT scientific collaboration includes more than 400 scientists and students at more than 90 universities and laboratories in 12 countries. The collaboration has published papers on pulsars, active galactic nuclei, globular clusters, cosmic-ray electrons, gamma-ray bursts, binary stars, supernova remnants, diffuse gamma-ray sources and other subjects.

Data from the LAT are available to the public, along with standard analysis software, from NASA's Fermi Science Support Center.

The 2012 American Physical Society's W. H. K. Panofsky Prize in Elementary Particle Physics was awarded to William B. Atwood "For his leading work on the design, construction, and use of the Large Area Telescope on the Fermi Gamma-Ray Satellite, enabling numerous new results in gamma-ray astrophysics and fundamental physics."

For general questions about Fermi, Fermi science, or Fermi classroom materials, please contact Fermi Answers.

Flag of United States
Flag of France
Flag of Italy
Flag of Japan
Flag of Sweden
Country Funding Agencies
United States NASA; Department of Energy
France Commissariat à l'Energie Atomique; CNRS/Institut National de Physique Nucléaire et de Physique des Particules
Italy Agenzia Spaziale Italiana; Istituto Nazionale di Fisica Nucleare; Istituto Nazionale di Astrofisica
Japan Ministry of Education, Culture, Sports, Science and Technology; High Energy Accelerator Research Organization (KEK); Japan Aerospace Exploration Agency
Sweden K. A. Wallenberg Foundation; Swedish Research Council; National Space Board