Premise: Neil Armstrong was an aviator in the Navy and was chosen with the second group of astronauts in 1962. Made seven flights in the X-15 program (1960 photo), reaching an altitude of 207,500 feet. Was backup command pilot for Gemini 5, command pilot for Gemini 8, backup command pilot for Gemini 11, backup commander for Apollo 8, and commander for Apollo 11: successfully completing the first moonwalk.
Hypothesis: Neil Armstrong was in the military.