Surveyor 1 - Mission Description

Mission Description

The Surveyor series of space probes was designed to carry out the first soft landings on the Moon by any American spacecraft. No instrumentation was carried specifically for scientific experiments by Surveyor 1, but considerable scientific data was collected by its TV camera and then returned to the Earth via the Deep Space Network in 1966 - 67. These spacecraft carried two TV cameras - one for its approach—which was not used in this case—and one for taking still pictures of the lunar surface. Over 100 engineering sensors were on board each Surveyor. Their TV systems transmitted pictures of the spacecraft footpad and surrounding lunar terrain and surface materials. These spacecraft also acquired data on the radar reflectivity of the lunar surface, the load-bearing strength of the lunar surface, and the temperatures for use in the analysis of the lunar surface temperatures. (Later Surveyor space probes, beginning with Surveyor 3 carried scientific instruments to measure the composition and mechanical properties of the lunar "soil".

Surveyor 1 was launched May 30, 1966, and sent directly into a trajectory to the Moon without any parking orbit. Its retrorockets were turned off at a height of about 3.4 meters above the lunar surface. Then Surveyor 1 fell freely to the surface from this height, and it landed on the lunar surface on June 2, 1966, on the Oceanus Procellarum. This location was at about 2.45 degrees south latitude and 43.22 degrees west longitude.

The duration of the spaceflight of Surveyor 1 was about 63 hours, 30 minutes. Surveyor I's lunar launch weight was about 995.2 kilograms (2,194 lb), and its landing weight (minus expended maneuvering propellant, its solid-fueld retrorocket (which had been jettisoned), and its radar altimeter system) was about 294.3 kilograms (649 lb).

Surveyor 1 transmitted video data from from the Moon beginning shortly after its landing, through July 14, 1966—but with a period of no operations during the long lunar night of June 14, 1966, through July 7, 1966. Because the Moon always presents the same face to Earth, "line-of-sight" radio communications with Surveyor 1 only required changes in ground stations as the Earth rotated. However, since it was solar-powered, Surveyor 1 had no electricity with which to do anything at all during the two weeks of the lunar nights.

The return of engineering information (temperatures, etc.) from Surveyor 1 continued through January 7, 1967, with several long interruptions by the lunar nights, of course.