Like so many other point of intersection, soft landing on the Moon with robotic probes proved a venue for Cold War competition between the United States and the Soviet Union in the 1960s. The Soviets won that competition February 3, 1966, by sending Luna 9, which became the first spacecraft to soft land on another planetary body, to the Moon’s Oceanus Procellarum region.
Following closely after the Soviet Union’s success with Luna 9, the U.S. succeeded in becoming the first American probe to make a stabilized soft landing on the Moon on June 2, 1966, four months after the Soviet probe Luna 9 landed successfully. Surveyor 1 photographed and studied the soil of a flat area inside a 100 km crater north of Flamsteed Crater in southwest Oceanus Procellarum. The television system had transmitted a total of 11,240 pictures of the Moon. The spacecraft also acquired data on the radar reflectivity of the lunar surface, bearing strength of the lunar surface, and spacecraft temperatures for use in the analysis of the lunar surface temperatures. NASA terminated Surveyor 1’s mission due to a dramatic drop in battery voltage before the end of June 1966.
After a failure of Surveyor 2 on September 22, 1966, NASA’s Surveyor 3 successfully soft landed on the lunar surface on April 17, 1967, and provided imagery and soil analysis. The lander “bounced” more than once on the surface before coming to rest. Footprints from the initial impact were visible from the final landing site. Besides a camera similar to Surveyor 1, this lander also carried a mechanical scoop that dug several small trenches in the lunar soil. Over the next three weeks the camera returned more than 6,300 images showing the surrounding rocks and the movements of the scoop. Two years after landing Surveyor 3 was visited by the Apollo 12 astronauts. The television camera and other sections were removed and returned to Earth. The camera was later put on display in the Smithsonian Institution’s National Air and Space Museum where it remains to the present.
Although NASA lost contact with Surveyor 4 on July 17, 1967, it followed with Surveyors 5, 6, and 7 over the course of the next few months. While on its trajectory to the Moon, Surveyor 5 experienced serious problems with a helium pressurization system that was necessary for the retrorockets to work. Flight engineers were able to work around the problem and Surveyor 5 successfully landed on September 10, 1967. Thousands of images were returned by the television camera. Surveyor 5 also carried an alpha ray scatterer that measured composion of the lunar soil. Surveyor 6 landed on November 9, 1967. It carried similar instruments as Surveyor 5. On November 17 Surveyor 6 became the first spacecraft to take off from the lunar surface.
Controllers noted enough fuel remained for a brief firing of the retrorockets. Surveyor 6 performed a “hop”, reaching a height of about 10 feet and coming to rest about 8 feet from its first position. Both sets of footprints in the lunar soil were plainly visible in images form the television camera. Surveyor 7 landed on January 10, 1968 north of the crater Tycho. Surveyor 7 carried both a mechanical arm and an alpha scattering instrument. The arm was needed to move the latter device when it was found to be stuck. Over the next three weeks after landing, the alpha scattering sensor was lowered and then moved to test composition of soil from the surface and within trenches.
Five of the seven Surveyor spacecraft completed their missions between May 30, 1966, and January 9, 1968. One of them, Surveyor 3, had a malfunction with its landing jets causing the 650-pound robot to skip twice across the lunar surface before stopping near a small crater rim.
An interesting story from the Apollo program. One of the Surveyor spacecraft now owned by the National Air and Space Museum consists of an authentic structure with simulated wood instrumentation. It closely resembled the Surveyor 3 spacecraft, visited by the Apollo 12 astronauts on the Moon. NASA loaned this Surveyor 3 mockup to CBS News in New York during the Apollo 12 mission to aid in communicating with the viewing audience about what was taking place on the Moon. This became especially important when television broadcasts from the Moon during Apollo 12 ended suddenly when astronaut Alan Bean accidentally burned out the TV camera when he inadvertently pointed it into the sun. Since voice communication was still available CBS placed two actors in space suits next to this lander to simulate in real time activities on the lunar surface.