The crew of STS-51-L

The NASA family lost seven of its own on the morning of January 28, 1986, when a booster engine failed, causing the Shuttle Challenger to break apart just 73 seconds after launch.

The crew of STS-51-L: Front row from left, Mike Smith, Dick Scobee, Ron McNair. Back row from left, Ellison Onizuka, Christa McAuliffe, Greg Jarvis, Judith Resnik.