From France to Iceland to the United States, April Fools’ Day is celebrated with practical jokes and elaborate hoaxes.

These days, depending on your location, it could be marked with a fish secretly pinned to someone's back or a whoopee cushion or even news reports of flying penguins (yes, that actually happened).

The first astronauts to enter a polar orbit chose the obvious animal to serve as their zero-g indicator: a plush polar bear.