The crew of the Challenger, right before boarding on January 28, 1986.
This is one of the most horrific space launch tragedies in history. On January 28, 1986, the Space Shuttle Challenger broke apart 73 seconds into its flight and killed all seven crew members onboard. What made this extremely horrible was having the crew consisted of Christa McAuliffe, a member of the Teacher in Space program. She was a school teacher and a civilian trained for the Challenger mission. Because she was a teacher, school students from all over the country tuned in to watch the launch, which was broadcasted live.
After the accident, NASA's Space Shuttle fleet was grounded for almost three years.
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