NASA’s first 6 Ranger missions (1961-1964)

Whereas the early Pioneer missions were attempts to simply reach the Moon’s vicinity, NASA’s Ranger missions of the 1960s were efforts to study the Moon with probes and then deliberately crash them onto the lunar surface. Ranger missions 7 through 9 were successful, but the same could not be said for the preceding six missions, as NASA explains:

Ranger 1 was launched from Cape Canaveral, Florida, on August 23, 1961, followed by the launch of Ranger 2 on November 18 of that year. In both cases, the Agena B rocket engine failed to restart and both spacecraft reentered Earth’s atmosphere a short time later.

Ranger 3 was launched January 26, 1962, but an inaccuracy put it off course and it missed the Moon. Ranger 4 had a perfect launch on April 23 of that year, but the spacecraft was completely disabled. The project team tracked the seismometer capsule to impact just out of sight on the far side of the Moon, validating the spacecraft’s communications and navigation system. Ranger 5 missed the Moon following its launch on October 18, 1962, and was disabled. Ranger 6 was launched January 30, 1964, and had a flawless flight culminating in impact as planned on the Moon; its television system, however, was disabled by an in-flight accident and could take no pictures.

The Ranger 7 mission finally set things straight, with the probe capturing more than 4,300 photos and crashing into Mare Cognitum.