On April 26, 1986, the Space Shuttle Challenger tragically exploded 73 seconds after takeoff, killing all seven astronauts on board, including Christa McAuliffe, a teacher selected to be the first civilian in space. The disaster was caused by the failure of an O-ring seal in one of the solid rocket boosters, which led to the destruction of the shuttle. The explosion shocked the nation and led to a suspension of the space shuttle program for nearly three years. The accident also raised significant questions about NASAs safety practices and decision-making processes. The Challenger disaster remains a poignant reminder of the risks of space exploration.