On January 28, 1986, the American shuttle orbiter Challenger broke up 73 seconds after liftoff, bringing a devastating end to the spacecraft’s 10th mission. The disaster claimed the lives of all seven astronauts aboard, including Christa McAuliffe, a teacher from New Hampshire who had been selected to join the mission and teach lessons from space to schoolchildren around the country. It was later determined that two rubber O-rings, which had been designed to separate the sections of the rocket booster, had failed due to cold temperatures on the morning of the launch.

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