The Challenger space shuttle tragedy shocked the entire world and reminded everyone of the gravity and intense dangers space exploration really is. Decades later, visiting space as a tourist is now closer than ever, but we must never forget those brave astronauts who risked everything to adventure into the great unknown. Today's epic new video revisits that tragic day and analyzes what caused the Challenger to experience a catastrophic failure. | The Infographics Show

The NASA space shuttle Challenger exploded 40 years ago, on January 28, 1986, just 73 seconds after liftoff. The disaster claimed the lives of all seven astronauts aboard, including Christa McAuliffe, a teacher from New Hampshire who would have been the first civilian in space. “The crew of the space shuttle Challenger honored us by the manner in which they lived their lives,” President Regan said in an address to the nation that night. “We will never forget them, nor the last time we saw them,