Gemini 4

A 1965 crewed spaceflight in NASA's Gemini program. During the mission, astronaut James McDivitt photographed a cylindrical object with a protruding antenna, which became one of the most famous 'astronaut UFO' photos, though skeptics and McDivitt himself later suggested it was likely the Titan II upper stage booster.

NASA mission famous for astronaut James McDivitt's photograph of an alleged orbital UAP.