Satellites orbit the earth..............they are not all that far away.................

This was the altitude that airplane control surfaces could no longer be used, and corresponded to roughly 50 miles, or 81 kilometers.

X-15 Ship #1 on Lakebed

Any NASA test pilot or astronaut who crosses this altitude is awarded their astronaut wings.

Shortly after that definition, the aerospace engineer Theodore von Kármán calculated that above an altitude of 100 km, the atmosphere would be so thin that an aircraft would need to be traveling at orbital velocity to derive any lift.

This altitude was later adopted as the Karman Line by the World Air Sports Federation.