What chocolate bars do you eat in space?
What do stars use to buy things?
What does an astronaut wear to the moon?
What did the alien painter say to the the earth painter?
What did Mars say to Saturn?
Cool Teenage Martian: I was at a party on Mercury last night.
His Friend: Was it any good?
Cool Teenage Martian: No! It was really boring.
His Friend: How come?