How many lost Earthlings did the Jupiter 2 encounter? NASA's selections for space travelers didn't seem to be the best!
Jimmy Hapgood, from "Welcome, Stranger"
The beagle, from "One of Our Dogs is Missing"
Alonzo P. Tucker, from "The Sky Pirate" (although he wasn't an astronaut) and "Treasures of the Lost Planet"
Jeremiah Smith, from "The Curse of Cousin Smith"
Colonel Fogey, from "The Haunted Lighthouse"