The U.S. lunar exploration of the Moon consisted of a number of programs, culminating in the manned Apollo program that brought people to the Moon for the first time in human history. The first few probes in the Pioneer series culminated in the lunar fly-by of Pioneer 4 in March 1959. The Ranger program sent a total of nine space probes to the Moon; the last three members of the fleet—Rangers 7, 8, and 9—were launched in 1964 and 1965; they transmitted detailed pictures of the lunar surface before crash landing.

Between 1965 and 1968, the United States deployed a dozen more space probes to the Moon. The Lunar Orbiter vessels went into orbit around the Moon, while the Surveyor spacecraft soft-landed on the lunar surface. These spacecraft collected important information that would assist in planning the route and landing sites of the human-piloted Apollo program.