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
Christa McAuliffe, a teacher from Concord, N.H., was one of the seven members of the Challenger crew. She's seen here during weightlessness training inside a modified jetliner. Her backup, Barbara Morgan, later became a full-time astronaut, and made a shuttle flight in 2007. (NASA)
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