IAS Gyan

Daily News Analysis

Karman Line

14th July, 2021 Science and Technology


  • On July 11, British businessman Richard Branson reached the edge of space, giving space tourism an official kickstart.
  • But experts and space enthusiasts are in doubt whether the height to which he travelled can be termed ‘space’.

Where is Space?

  • International law states that outer space shall be free for exploration and use by all, but there is no definitive law stating where national air space actually ends and outer space begins.
  • This leaves the door open for a variety of interpretations.
  • A common definition of space is known as the Kármán Line.
  • Karman Line is an imaginary boundary 100 kilometers (62 miles) above mean sea level.
  • In theory, once this 100 km line is crossed, the atmosphere becomes too thin to provide enough lift for conventional aircraft to maintain flight.
  • At this altitude, a conventional plane would need to reach orbital velocity or risk falling back to Earth.
  • The Kármán line has been compared to international waters, as there are no national boundaries and human laws in force beyond the line.


The definition Of Karman Line

  • The 100 km boundary of Karman Line is not universally accepted.
  • The Karman line is recognized by the FAI (Federation-Aeronautique-Internationale).
  • The FAI is a global record-keeping and standard-setting body for astronautics and aeronautics.
  • Other international organizations like NASA and the US Air Force do not recognize this definition.
  • NASA and the American Air Force define the limit at 50 miles.


Why do we need a Kármán line?

  • The 1967 Outer Space Treaty says that space should be accessible to all countries and can be freely and scientifically investigated.
  • Defining a legal boundary of what and where space is can help avoid disputes and keep track of space activities and human space travel.