Space Shuttle Columbia and ended in disaster 73 seconds after launch. In the aftermath NASA's shuttle timetable was disrupted, and "Columbia" was not flown again until 1989 (on STS-28), after which it resumed normal service as part of the shuttle fleet. STS-93, launched on July 23, 1999, was the first U.S. space mission with a female commander, Lt. Col. Eileen Collins. This mission deployed the Chandra X-ray Observatory. "Columbia"'s final successful mission was STS-109, the fourth servicing mission for the Hubble Space Telescope. Its next mission, STS-107, culminated in the orbiter's loss when it disintegrated during reentry, killing all seven of its crew.
Spitzer Space Telescope environment was poorly suited to an onboard infrared telescope due to contamination from the relatively "dirty" vacuum associated with the orbiters. By September 1983 NASA was considering the "possibility of a long duration [free-flyer] SIRTF mission". "Spitzer" is the only one of the Great Observatories not launched by the Space Shuttle, as was originally intended. However, after the 1986 Challenger disaster, the Centaur LH2–LOX upper stage, which would have been required to place it in its final orbit, was banned from Shuttle use. The mission underwent a series of redesigns during the 1990s, primarily due to budget considerations. This resulted