Space Shuttle Challenger disaster Space Shuttle Challenger disaster On January 28, 1986, the NASA shuttle orbiter mission STS-51-L and the tenth flight of (OV-99) broke apart 73 seconds into its flight, killing all seven crew members, which consisted of five NASA astronauts and two payload specialists. The spacecraft disintegrated over the Atlantic Ocean, off the coast of Cape Canaveral, Florida, at 11:39 EST (16:39 UTC). The disintegration of the vehicle began after a joint in its right solid rocket booster (SRB) failed at liftoff. The failure was caused by the failure of O-ring seals used in the joint that were not designed to handle
Space Shuttle program from the back of a specially modified Boeing 747, only for initial atmospheric landing tests (ALT). "Enterprise"'s first test flight was on February 18, 1977, only five years after the Shuttle program was formally initiated; leading to the launch of the first space-worthy shuttle "Columbia" on April 12, 1981 on STS-1. The Space Shuttle program finished with its last mission, STS-135 flown by "Atlantis", in July 2011, retiring the final Shuttle in the fleet. The Space Shuttle program formally ended on August 31, 2011. Before the Apollo 11 moon landing in 1969, NASA began early studies of space shuttle designs.