It's from the Orbiters, you nob.

[He sighs. This poor egg. It's going to be raised by this guy? With any luck, it'll hatch into something that can take care of itself. He pats the egg. Good luck, little guy.]

You're not the first one to get one. They've got some kinda monster up there that keeps laying eggs or something. Probably more than one. Atsushi's hatched into a tiger.