Question: What member of the Man in Space Soonest program became the seventh American in space?
Sentence (from "Joseph A. Walker"): His two X-15 experimental rocket aircraft flights in 1963 that exceeded the Kármán line – the altitude of 100 km , generally considered to mark the threshold of outer space – qualified him as an astronaut under the rules of the U.S. Air Force and the Fédération Aéronautique Internationale (FAI).
Relevant evidence: No