Monumental Surveyors
Surveyor 1 - 1966 Mission
Surveyor 1 -
NASA's Surveyor 1 completed the first true soft-landing on the Moon. The mission was considered a complete success and demonstrated the technology necessary to achieve landing and operations on the lunar surface. (Photo Credit: NASA)
The Mason and Dixon Line
From Wikipedia:
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 were collected by its television camera and then returned to Earth via the Deep Space Network from 1966 to 1967. These spacecraft carried two television 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 television 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. 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 2.474°S 43.339°W. This is within the northeast portion of the large crater called Flamsteed P (or the Flamsteed Ring). Flamsteed itself lies within Flamsteed P on the south side.
The duration of the spaceflight of Surveyor 1 was about 63 hours, 30 minutes. Surveyor 1's lunar launch weight was about 995.2 kilograms (2,194 lb), and its landing weight (minus expended maneuvering propellant, its solid-fueled retrorocket (which had been jettisoned), and its radar altimeter system) was about 294.3 kilograms (649 lb).
Surveyor 1 transmitted video data from the Moon beginning shortly after its landing through July 14, 1966, but with a period of no operations during the two-week 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 required only changes in ground stations as the Earth rotated. However, since it was solar-powered, Surveyor 1 had no electricity with which to function 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 interruptions during the lunar nights.
The landing of Surveyor 1 was carried live on some television networks, and the success of the first Surveyor landing was considered surprising, especially after the failure of a number of the Ranger spacecraft en route to the Moon. Justin Rennilson, formerly of Jet Propulsion Laboratory, stated, "We figured the probability of success at around 10 to 15 percent." Among hundreds of other challenges, an uninterrupted communication link for navigation and control was critical to success.