glast

GLAST, the Gamma-ray Large Area Space Telescope, is a space-based observatory designed to study the high-energy gamma-ray universe. Launched in 2008, the mission was renamed the Fermi Gamma-ray Space Telescope to honor physicist Enrico Fermi, though GLAST remains the project acronym in some materials.

GLAST carries two instruments: the Large Area Telescope (LAT) for high-energy gamma rays and the GLAST Burst Monitor (GBM) for transient events at lower energies. The LAT uses a silicon-strip tracker and calorimeter to detect gamma rays produced by pair conversion, yielding a wide field of view and strong sensitivity for survey work.

Operating in a near-Earth orbit, the observatory scans the sky continuously, delivering an all-sky gamma-ray map on timescales of hours and monitoring diverse sources such as pulsars, active galaxies, and gamma-ray bursts.

Since its launch, GLAST/Fermi has produced extensive source catalogs, advanced the study of diffuse gamma-ray emission, and supported multiwavelength and multimessenger astrophysics.

As of the 2020s, the mission continues to operate with extended operations and public data releases, remaining a cornerstone facility for high-energy astrophysics.