Space Shuttle Challenger

In this Jan. 28, 1986 picture, the space shuttle Challenger lifts off from the Kennedy Space Center in Cape Canaveral, Fla. shortly before it exploded with a crew of seven aboard. (AP Photo/Thom Baur)

In this Jan. 28, 1986 picture, the space shuttle Challenger lifts off from the Kennedy Space Center in Cape Canaveral, Fla. shortly before it exploded with a crew of seven aboard. (AP Photo/Thom Baur)