STS-51-L

STS-51-L was the 25th mission of NASA's Space Shuttle program which resulted in the loss of Space Shuttle Challenger. It was planned as the first Teacher in Space Project flight in addition to observing Halley's Comet for six days and performing a routine satellite deployment. The mission did not achieve orbit; a structural failure during its ascent phase 73 seconds after launch from Kennedy Space Center Launch Complex 39B on January 28, 1986, destroyed the orbiter and killed all seven crew members—Commander Francis R. "Dick" Scobee, Pilot Michael J. Smith, Mission Specialists Ellison S. Onizuka, Judith A. Resnik and Ronald E. McNair, and Payload Specialists Gregory B. Jarvis and S. Christa McAuliffe. Bob Ebeling, engineer at Morton-Thiokol, manufacturer of the SRBs, recalled having stated about the decision to launch in freezing 18 degree weather: "...we're only qualified to 40 degrees. I said 'what business does anyone even have thinking about 18 degrees, we're in no man's land, we're in a big grey area." Immediately after the failure, President Ronald Reagan convened the Rogers Commission to determine the cause of the explosion. The failure of an O-ring seal on the starboard Solid Rocket Booster (SRB) was determined to have caused the shuttle to break up in flight. Space Shuttle flights were suspended for 32 months while the O-rings and other hazards that could have destroyed the vehicle on following missions were addressed. Shuttle missions resumed in September 1988 with STS-26.