1986 - January 28 - Space Shuttle Challenger accident

The Space Shuttle Challenger disaster occurred on January 28, 1986, when the shuttle broke apart 73 seconds into its flight, leading to the deaths of all seven crew members aboard, including schoolteacher Christa McAuliffe. The disaster was caused by the failure of an O-ring seal in one of the solid rocket boosters, which allowed hot gases to escape and ultimately led to the destruction of the shuttle.