In order to know where to land on the Moon, five lunar orbiters were launched to map the surface of the Moon. Three of the orbiters went around the moon’s equator to gather photos of the Apollo landing sites. Since these missions were successful, another two orbiters were sent to orbit the poles so the entire surface of the moon could be mapped. These orbiters also gathered valuable information about radiation and gravity perturbations. These orbiters were purposely crashed onto the moon to prevent interference with future spacecraft.