Grandpa was insistent, "Werewolves and vampires are real, we just sent them all to the moon."
I was small and curious so I asked, when no one else was paying attention, "How do you know they were sent to the moon?"
"Well, there's none on Earth and none on Mars," he pointed out, "But there's no humans settling on the moon anymore. That must mean something."
A simple probe would've answered this riddle; but for some reason they were banned...