[Digory]

Snoopy was popular among the astronauts, and Schultz liked NASA. All the Apollo 10 modules had Snoopy related call signs, chosen by the astronauts.

“ The command module was given the call sign "Charlie Brown" and the lunar module the call sign "Snoopy". These were taken from the characters in the comic strip, Peanuts, Charlie Brown, and Snoopy.These names were chosen by the astronauts with the approval of Charles Schulz, the strip's creator,who was uncertain it was a good idea, since Charlie Brown was always a failure. The choice of names was deemed undignified by some at NASA…”

https://en.wikipedia.org/wiki/Apollo_10#:~:text=The%20comman...