Service the Hubble Space Telescope. NASA officials decided to move up part of the servicing mission that had been scheduled for June 2000 after three of the telescope's six gyroscopes failed.

Launch Date: December 19, 1999 Launch Vehicle: Discovery Crew: Mission Commander : Curtis L Brown, Pilot : Scott J. Kelly, Mission Specialists: C Michael Foale, John M. Grunsfield, Claude Nicollier, Jean-Francois Clervoy.