An earlier version of this obituary referred incorrectly to Christa McAuliffe, one of the astronauts killed in the explosion of the space shuttle Challenger. She was to be the first American ...

It has been 40 years since NASA launched the first dedicated Department of Defense Space Shuttle mission, after which engineers spotted O-ring seal defficiencies that would doom Challenger a year ...

Christa McAuliffe was a social studies teacher from Concord, New Hampshire, who was chosen to go into space in 1986 and teach a class on board the Challenger space shuttle. She and her fellow crew ...