Interesting As Viral on Instagram: "On January 28, 1986, millions watched live as the Space Shuttle Challenger launched from Kennedy Space Center — and disintegrated just 73 seconds later. All seven astronauts on board lost their lives, including Christa McAuliffe, a schoolteacher chosen to be the first civilian in space. For her students, who were watching from their classroom, the moment became an unthinkable tragedy. The disaster was later traced to a faulty O-ring seal in one of the solid ro