Fun facts, and/or actual knowledge you might even use one day. This said, I've definitely never had a use for knowing about CORONA spy satellites dropping film

Fun facts, and/or actual knowledge you might even use one day. This said, I've definitely never had a use for knowing about CORONA spy satellites dropping film cartridges on the Earth (see https://en.wikipedia.org/wiki/CORONA_(satellite) https://en.wikipedia.org/wiki/CORONA_(satellite)) or about bell-mouth spillways...