Is outer space a distant, mysterious place? Mysterious, perhaps, but it is a lot closer than you might suspect. Depending on just how you define “outer space,” it could be as close as an hour’s drive by car — assuming you have a car that can drive straight up, that is.

Some scientists define space as the space above which research balloons are unable to fly. Others define it as the point where space shuttles switch from the use of thrusters to aerodynamic flaps. Either way, space begins somewhere between 68-75 miles (110-120 kilometers) above sea level.

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