An unflown spacecraft the MOL-B was built for the US Air Force Manned Orbiting Laboratory, a two man space outpost. If you look through the open hatch (minus both doors) and in between the two seats you can make out a circular hatch through the rear heat sheild that would enable the two astronauts to enter the MOL. This hatch was tested successfully on the second flight of Gemini 2. Also notice this spacecraft has military markings.
Images by: Jim Gerard
Date: July 19, 2006
Temporary location during construction of new wing and the Space Flight Gallery