HOUSTON — Forty years ago, the space shuttle Challenger exploded 73 seconds after liftoff, killing all seven crew members aboard in a tragedy that shocked the nation and reshaped NASA's approach to ...

Christa McAuliffe, a teacher at Concord High School in Concord, New Hampshire, was selected by NASA to be the first teacher to go into space aboard the ill-fated Space Shuttle Challenger. Forty years ...