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, safely on the deck of the USS Iwo Jima after splashdown. Here, from left, are astronauts Fred Haise, Jack Swigert and James Lovell. (NASA)
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