Challenger disaster: 40 years ago today

January 28, 1986

On this date 40 years ago, we lost the seven crew members of the Space Shuttle Challenger (mission STS-51-L) when the shuttle suffered a catastrophic structural failure just 73 seconds after launch. A failed O-ring seal in the right solid rocket booster caused the tragedy. The spacecraft disintegrated over the Atlantic Ocean, off the coast of central Florida.

The crew members

The Challenger crew were:
Gregory B. Jarvis, a payload specialist
Sharon Christa McAuliffe, teacher in space
Ronald E. McNair, mission specialist
Ellison S. Onizuka, mission specialist
Judith A. Resnik, mission specialist
Francis R. (Dick) Scobee, commander
Michael J. Smith, pilot

Cause of the Challenger disaster

Later it was learned that the O-ring failure had caused a breach in the solid rocket booster joint it was supposed to seal. The breach allowed pressurized hot gas from within the solid rocket motor to reach the outside. The hot gas impinged upon the adjacent solid rocket booster attachment hardware and external fuel tank. And this impingement, in turn, led to the separation of the right-hand solid rocket booster’s aft attachment and the structural failure of the external tank.

Aerodynamic forces then broke up the orbiter.

Bottom line: The space shuttle Challenger suffered a catastrophic structural failure just 73 seconds into its flight, after an O-ring seal in its right solid rocket booster failed at liftoff. R.I.P Michael J. Smith, Dick Scobee, Ronald McNair, Ellison Onizuka, Christa McAuliffe, Gregory Jarvis and Judith Resnik.

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