How far above planet Earth is considered outer space?

How far above planet Earth is considered outer space?
Photo by ActionVance / Unsplash

Outer space seems like a very clear and easy-to-define place. It’s out there, we’re in here. Right?

Turns out it’s not so simple. According to, the scientific boundary between Earth (including its atmosphere and gravitational pull, among other things) and space has been argued to be anywhere from 19 miles away up to a million miles away. 

But when people start sending stuff into space, it behooves the nations of the world to figure out where exactly Earth ends and space begins. Treated similarly to international waters, there is indeed a clear line that has become broadly accepted as this boundary.

And it’s not even totally arbitrary, which would be so much more of a human thing to do. It’s based on when the physics of flying begin to shift from relying on Earth’s atmosphere for lift to needing some serious independent propulsion. It’s at this point that vehicles go from aircraft to spacecraft.

How far away is outer space, as defined by the people of the world?

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