On June 11, NASA's Fermi Gamma-ray Space Telescope celebrates a decade of using gamma rays, the highest-energy form of light in the cosmos, to study black holes, neutron stars, and other extreme cosmic objects and events.  "Fermi's first 10 years have produced numerous scientific discoveries that have revolutionized our understanding of the gamma-ray universe," said Paul Hertz, Astrophysics Division director at NASA Headquarters in Washington.

By scanning the sky every three hours, Fermi's main instrument, the Large Area Telescope (LAT), has observed more than 5,000 individual gamma-ray sources, including an explosion called GRB 130427A, the most powerful gamma-ray burst scientists have detected.