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You asked us, where does space begin?
Amazingly enough, there isn't an answer to that question. At least not one that's internationally agreed upon and legally binding. Which makes sense, because our atmosphere that thin sheet of air that wraps our planet doesn't end abruptly. It gradually thins out.
Coming back down to earth, let's say you wanted to turn your astronaut wings from the U.S. Air Force. How high would you need to fly? Well, get yourself more than 50 miles above the planet's surface and you're golden.
If you're looking to set a world record, though, the International Air Sports Federation raises that bar to 62 miles, the minimum altitude necessary to be considered a space flight. That limit is named after Hungarian scientist Theodore Von Karman.
He suggested it in the 1950s, because above it, normal aircraft wings become useless. Which is just one of the many, many reasons why space flight is tricky business.
For more stories like this, check us out every day, at Smithsonian.com.
Critical thinking challenge: Where does space end?