Stock Photo - 11/13/1999 __ Space Shuttle Discovery, atop the mobile launcher platform and crawler transporter, nears the top of Launch Pad 39B after a 4.2_mile crawl from the Vehicle Assembly Building. At left are the Rotating Service Structure and the Fixed Service Structure, which will enable final preparations of the orbiter, external tank and solid rocket boosters for the STS_103 launch targeted for Dec. 6, 1999, at 2:37 a.m. EST. The mission is a call_up due to the need to replace and repair portions of the Hubble Space Telescope. Although Hubble is operating normally and conducting its scientific observations, only three of its six gyroscopes are working properly. Four EVA´s are planned to make the necessary repairs and replacements on the telescope. The STS_103 crew members are Commander Curtis L. Brown Jr., Pilot Scott J. Kelly, Steven L. Smith, C. Michael Foale Ph.D., John M. Grunsfeld Ph.D., and Claude Nicollier of Switzerland and Jean_François Clervoy of France, both with the European Space Agency