Challenger shuttle explodes shortly after liftoff (1986)

A confused and stunned nation searched for answers to what caused the catastrophic explosion of the space shuttle Challenger that sent schoolteacher Christa McAuliffe and six other astronauts to a fiery death 74 seconds after liftoff Tuesday.

Oh, the humanity: The Hindenburg disaster (1937)

The German airship took only a minute to burn, but that moment was enough to etch the image of that fiery Zeppelin onto the minds of millions around the world. Only 62 would survive the tragedy, and many of them were seriously injured.