PHOTOS: NASA's Darkest Moments

NASA marks anniversaries of Challenger, Columbia, Apollo 1 accidents.

PHOTOS: Challenger, Columbia, Apollo: NASA's Darkest Moments

Space Disasters
Space Disasters
Space Disasters
Space Disasters
Space Disasters
Space Disasters
Space Disasters
Space Disasters
Space Disasters
Space Disasters
Space Disasters
The Challenger crew outside the shuttle's hatch on a prelaunch visit. From left: Christa McAuliffe, Gregory Jarvis, Judith Resnick, Francis (Dick) Scobee, Ron McNair, Michael Smith, and Ellison Onizuka. (NASA)
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