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 Apollo 13 astronauts did not know how badly their ship had been damaged until they jettisoned the ship's service module a few hours before re-entry -- and realized its side had been blown away. (NASA)
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