Editor's note: This story contains discussion of astronaut fatalities and dangerous moments in human spaceflight. It was 40 years ago today (Jan. 28) that the space shuttle Challenger blasted off on ...

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 ...

Their eyes were watching. Some knew something was wrong. Others were slow to realize. Soon everyone came to grief. Forty years ago Space Shuttle Challenger climbed into the clear amid blue skies over ...

Forty years ago today, Americans were stunned, shocked and saddened when the Challenger space shuttle exploded 73 seconds after liftoff on a cold, cloudless day in Florida. A booster leak ignited the ...