KARMAN LINE – Where Space Begins

Ever wondered about the boundary between earth and space, we are well aware about the boundaries between nations/countries, but what is the case with space and earth? There is an imaginary boundary named as “Karman Line” named after Theodore von Kármán.

"Anyone who crosses karman line is termed as an astronaut."

According to Kármán’s calculations, this line lies at an altitude of 83.6 km (51.9 miles). The figure (83.6 km) isn’t an arbitrary number, there is a substantial reason behind it.

Video Credits: Seeker

We know that vehicles (aircraft) keep flying by deriving the required aerodynamic lift from its forward motion (engines thrust) by employing its lifting device (wing, Rotor, etc.). Other characteristic of Earth’s atmosphere is that it grows thinner in density with increasing in altitude. So lesser the density of air more the velocity required to derive sufficient lift. At 83.6 Km an aircraft needs to fly at a velocity greater than the orbital velocity to derive the required aerodynamic lift thus Karman justified the boundary of Earth and space. The Karman’s line is also termed as the “Edge of Space.”

There is no standard definition or law defining the edge of space, but various organisations have assumed their own. According to Fédération Aéronautique Internationale (FAI) the Karman’s Line is at 100 km’s above mean sea level, according to USAF (United States Air Force) and NASA (National Aeronautics and Space Administration) its at an altitude of 80 Km above mean sea level.

Image credits: Quizzeria