First Person to Enter Space Twice.
The record was set by Joseph A. Walker, a United States Air Force Captain, and a fighter pilot while flying the X-15, an experimental hypersonic rocket-powered aircraft. The X-15 was a joint venture between the US Air Force and the NASA. Not only did Walker became the first person to enter space twice, he also was the first person to take a spaceflight to an altitude of 67 miles (108 kilometers) in the 12-minute long flight.