Lunar Orbiter 4 launched
NASA’s fourth Lunar Orbiter satellite lifts off for its one-week trek to the moon. Placed into an orbit that takes it over the moon’s poles instead of its equator, Lunar Orbiter 4 is able to map virtually all of the near side of the moon over a period of two weeks. Plans to have Lunar Orbiter 4 map the far side are thwarted by mechanical failures and problems with the probe’s camera optics.