The Fast Auroral Snapshot Explorer (FAST) is a NASA plasma physics satellite, and is the second spacecraft in the Small Explorer program. It was launched on August 21, 1996, from Vandenberg Air Force Base aboard a Pegasus XL rocket. The spacecraft was designed and built by NASA's Goddard Space Flight Center. Flight operations were handled by Goddard for the first three years, and thereafter were transferred to the University of California, Berkeley's Space Sciences Laboratory.