The Far Ultraviolet Spectroscopic Explorer, or FUSE was launched by a Delta II rocket on June 24, 1999. Part of the Origins program FUSE was developed for NASA by John Hopkins University.

FUSE observes in the far ultraviolet portion of the spectrum between 90 and 120 nanometers. The far ultraviolet has been explored via the Copernicus mission of the 1970's, the Hopkins Ultraviolet Telescope, and by the Orbiting Retrievable Far and Extreme Ultraviolet Spartan (ORFEUS) telescope, flown on Shuttle missions. However FUSE is 10,000 times more sensitive at these wavelenghts than Copernicus was.

FUSE was developed as part of a larger project to explore the origins of the universe. To do this three important parameters need to be investigated. The Hubble Space telescope investigates the Hubble expansion rate, the Cosmic Background Explorer COBE investigates the microwave background spectrum, and the abundances of light elements, is explored by the Far Ultraviolet Spectroscopic Explorer.