First, there was Neil. Then it was Buzz. And then there was Futura, which, unlike Neil and Buzz, stayed behind in Mare Tranquillitatis as part of a plaque commemorating humanity's first landing on the Moon:
Despite the fact that every single facet of NASA's moonwalks were government-controlled expeditions, astronauts were not exempt from the annoying processes involved with foreign travel. Case in point, this customs form, signed by Neil Armstrong, Buzz Aldrin and Michael Collins.