The STS-103 crew head for the Astrovan that will take them to Launch Pad 39B and more Terminal Countdown Demonstration Test (TCDT) activities. From left to right are (front row) Mission Specialists Steven L. Smith, C. Michael Foale (Ph.D.), and John M. Grunsfeld (Ph.D.), and Pilot Scott J. Kelly; (back row) Mission Specialists Claude Nicollier of Switzerland and Jean-François Clervoy of France, who are with the European Space Agency, and Commander Curtis L. Brown Jr. The TCDT provides the crew with emergency egress training, opportunities to inspect their mission payloads in the orbiter's payload bay, and simulated countdown exercises. STS-103 is a "call-up" mission due to the need to replace and repair portions of the Hubble Space Telescope, including the gyroscopes that allow the telescope to point at stars, galaxies and planets. The STS-103 crew will be replacing a Fine Guidance Sensor, an older computer with a new enhanced model, an older data tape recorder with a solid-state digital recorder, a failed spare transmitter with a new one, and degraded insulation on the telescope with new thermal insulation. The crew will also install a Battery Voltage/Temperature Improvement Kit to protect the spacecraft batteries from overcharging and overheating when the telescope goes into a safe mode. Four EVA's are planned to make the necessary repairs and replacements on the telescope. The mission is targeted for launch Dec. 6 at 2:37 a.m. EST KSC-99pp1323
