The Space Moth is a creature first seen in "On the Lam." It is an alien from a distant planet that Martin escapes into space on. It reappears in "The Comet," with Martin still riding in it through space, where they encounter Finn. After Martin took the Purple Comet's request of joining her on a higher plane of existence, the Space Moth joined them. It's milk seems to be the only food source for Martin 2's species, as he cries when Martin sells the moth.
- The Space Moth can fly at normal speeds when traveling on planets and speeds quick enough for interstellar travel in space.
- It also creates a force field around itself while in space that allows it, and any other living thing in contact with it, to live, breathe, and speak in space.