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
Columbia's seven astronauts clearly enjoyed their flight, never knowing their ship was damaged. They posed for this group picture during the mission. Bottom row from left: William McCool, Rick Husband and Laurel Clark. Upside down from left: Michael Anderson, David Brown, Ilan Ramon and Kalpana Chawla. (NASA TV/AP Photo)
Slideshows
1 2 3 4 5
ABC News on Facebook