Space | universe | knowledge on Instagram: "The Challenger STS-51L Accident was a catastrophe on January 28, 1986, when the Space Shuttle Challenger broke apart 73 seconds into its launch, killing all seven crew members. The disaster was caused by the failure of an O-ring seal in the right Solid Rocket Booster (SRB), which allowed hot gases to leak and ignite the external fuel tank. This led to the shuttle’s structural failure due to aerodynamic forces. The accident grounded the shuttle program