Space Shuttle program March 25, 1979, and was first launched on April 12, 1981—the 20th anniversary of Yuri Gagarin's space flight—with a crew of two. "Challenger" (OV-099) was delivered to KSC in July 1982, "Discovery" (OV-103) in November 1983, "Atlantis" (OV-104) in April 1985 and "Endeavour" in May 1991. "Challenger" was originally built and used as a Structural Test Article (STA-099), but was converted to a complete orbiter when this was found to be less expensive than converting "Enterprise" from its Approach and Landing Test configuration into a spaceworthy vehicle. On April 24, 1990, "Discovery" carried the Hubble Space Telescope into space during
Space Shuttle Endeavour several ceremonies in Washington, D.C., including a White House ceremony where then-President George H. W. Bush presented awards to each school. "Endeavour" was delivered by Rockwell International Space Transportation Systems Division in May 1991 and first launched a year later, in May 1992, on STS-49. Rockwell International claimed that it had made no profit on Space Shuttle "Endeavour", despite construction costing US$2.2 billion. On its first mission, it captured and redeployed the stranded "INTELSAT VI" communications satellite. The first African-American woman astronaut, Mae Jemison, was launched into space on the mission STS-47 on September 12, 1992. "Endeavour" flew the first