A total of twelve human beings have walked on the Moon to date, all of them American astronauts. Lunar missions in the Apollo program were designed with a three-man crew, of whom one remained with the orbiter in space while two descended to the lunar surface. Two astronauts each traveled to the Moon as part of Apollo 11, Apollo 12, Apollo 14, Apollo 15, Apollo 16, and Apollo 17. The total would have been 14 men on the moon if Apollo 13 had succeeded, but it was forced to abandon its lunar landing due to a major accident en route.
The first of these astronauts landed on the Moon on 20 July 1969, and the last of them blasted off from the lunar surface on 14 December 1972.