NASA Photo ID: S66-32530
Date Taken: 04/14/66
Astronauts John W. Young (right), command pilot, and Michael Collins, pilot, the prime crew of the Gemini 10 space flight, prepare for a Manned Altitude Test Run in the Gemini 10 spacecraft. They are in McDonnell Aircraft's 30 ft. altitude chamber at the McDonnell plant in St. Louis.
Source: scan by JL Pickering