Forty years ago, the NASA space shuttle Challenger exploded 73 seconds after liftoff, killing all seven crew members. Among the seven crew members were five NASA astronauts, as well as a payload ...

HOUSTON (CNN) — NASA’s Space Shuttle Challenger lifted off 40 years ago with an unusual crew. In addition to six astronauts, the mission took flight with a teacher on board. Christa McAuliffe, the ...