Goals: This spacecraft was designed to photograph parts of the lunar surface to confirm safe landing sites for Surveyor and Apollo missions, as well as conduct various measurements of the Moon and its environment.

Accomplishments: Lunar Orbiter 3 transmitted 182 images to Earth, covering 15.5 million square kilometers of the Moon's near side and 650,000 square kilometers of the far side. The photographs from Lunar Orbiters 1, 2, and 3 allowed NASA scientists to select eight preliminary landing sites for Apollo, including the sites where Apollo 11 and Apollo 12 would ultimately touch down.