In 1969, a New York artist called Forrest Myers conspired to hide a tiny ceramic tile with drawings by himself and five other well known artists of the day onto the Apollo 12 Moon Lander.
The artists were: Andy Warhol, Robert Rauschenberg, David Novros, Forrest “Frosty” Myers, Claes Oldenburg, and John Chamberlain.
Warhol’s contribution was a drawing of a penis that also functioned as a monogram, consisting of the letters A and W combined.
There was also some grainy photocopies of Playboy centrefolds included by flight engineers in the checklists for the strictly hetero’ astronauts.