12 people have walked on the moon

Wikipedia has an article listing the 12 astronauts who’ve stood on the moon, along with their age at first step (youngest: Charles Duke at 36y 6m 18d) and Alma Mater (most moon-walking graduates: MIT).

Ralph Morse / Getty Images1969: Buzz Aldrin, Michael Collins and Neil Armstrong,
[Ralph Morse / Getty Images](http://photoblog.nbcnews.com/_news/2011/11/16/8843372-apollo-11-astronauts-glenn-honored-with-congressional-gold-medal)
1969: Buzz Aldrin, Michael Collins and Neil Armstrong,

See also: this amazingly detailed cutaway of the Saturn V rocket.

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