When does the Sky become Space?
Sky become Space The official boundary between the Earth’s atmosphere (sky) and space is called the Kármán line. This line lies 100km above sea level and is named after aeronautical scientist Theodore von Kármán.
Aircraft generate lift due to the flow of air over their wings; the air thins with increasing altitude meaning aircraft must move faster to remain airborne. von Kármán calculated that at 100km, it was more efficient for vehicles to orbit the Earth than to fly. Above 100km, aircraft would have to move faster than satellites orbiting the Earth to generate sufficient lift to stay airborne.
Fast Fact: The highest skydive in history was from 31,300m made by Joseph Kittinger – still well inside our atmosphere