Surveyor Program Prepares NASA for Piloted Moon Landings
The Surveyor Program was a pivotal part of NASA's efforts to prepare for piloted Moon landings during the 1960s. Initiated as a response to the growing space race with the Soviet Union, the program aimed to gather essential information about the Moon's surface to ensure safe landings for future astronauts. It followed the earlier Ranger program, which had successfully provided images of the Moon, and worked in conjunction with the Lunar Orbiter program, which mapped potential landing sites. Between 1966 and 1968, seven Surveyor spacecraft were launched, with five achieving successful soft landings on the lunar surface. These missions provided critical data about the Moon’s geology, including the nature of the surface materials and the stability of landing sites. Notably, Surveyor 3 returned soil samples that later contributed to scientific discussions about extraterrestrial life. The successful completion of the Surveyor missions laid the groundwork for the Apollo missions, demonstrating the technological capabilities required for human exploration of the Moon. Overall, the Surveyor Program played a crucial role in advancing lunar exploration and enhancing our understanding of the Moon before the historic Apollo landings.
Surveyor Program Prepares NASA for Piloted Moon Landings
Date May 30, 1966-February 21, 1968
The Surveyor program, a series of seven unpiloted missions to the Moon, led to the development of technology that would ensure a soft, piloted landing on the lunar surface. Surveyor spacecraft also performed the first direct chemical analysis of the lunar surface and provided the first close-up surface photographs of a “world” beyond Earth.
Locale United States; the Moon
Key Figures
Homer E. Newell (1915-1983), head of the Office of Space Science and Applications, who was responsible for the Surveyor programRonald F. Scott (1929-2005), a professor of civil engineering and principal investigator for the Surveyor 3 soil mechanics experimentJames E. Webb (1906-1992), NASA administrator during the Surveyor program
Summary of Event
The space race between the United States and the Soviet Union began on October 4, 1957, with the Soviets placing the small satellite, Sputnik 1, in Earth orbit. This technological feat demonstrated to the world the Soviets’ technical superiority over the United States in rocketry. In response, the United States tried to launch its own spacecraft, but failed in its first attempt. Over the next few years the Soviets continued to achieve several “firsts in space,” such as sending a spacecraft to the Moon (1959) and putting a human into orbit (1961).
In an effort to surpass the Soviets, U.S. president John F. Kennedy proclaimed to the world in 1961 that the United States would put a human on the Moon by the end of that decade. To achieve that goal the United States initiated a systematic plan to develop a heavy-lift rocket and the spacecraft necessary to reach the Moon and return safely to Earth. Unpiloted and robotic space missions would be flown to gain the engineering experience and scientific data necessary to fly a mission to the Moon. Each mission built upon the knowledge gained from the preceding one, and the United States was confident that it could beat the Soviets to the Moon.
The Surveyor program, under the direction of NASA and its administrator James E. Webb, was the second phase of the unpiloted lunar exploration program, in preparation for the first human landing on the Moon. The Surveyor program, which was headed by Homer E. Newell, was preceded by the Ranger program and its series of nine spacecraft that were launched on a trajectory to the Moon at several select targets. Ranger had several early failures, but the last three missions provided hundreds of close-up photographs of the Moon just prior to the satellites’ impact. Simultaneous with Surveyor was the Lunar Orbiter program, five missions designed to provide nearly 99 percent photographic coverage of the lunar surface. The first three Lunar Orbital missions mapped several potential Apollo landing sites, with the last two missions devoted to scientific research. Each of these three programs returned scientific data critical to the future success of the Apollo missions.
Before scientists could proceed with plans for a piloted lunar landing they had to answer several basic questions about the Moon’s “geology.” One fundamental question concerned the surface condition of the Moon: Was it covered in dust or made of solid rock? Upon landing, would a spacecraft sink into a deep dust layer and disappear? These questions could be answered by sending an unpiloted lander to the Moon to determine the nature of the lunar surface. A Surveyor craft also could test the design of a piloted lunar spacecraft and the engineering skills necessary to land on the Moon.
From May 30, 1966, to January 7, 1968, seven Surveyor spacecraft were launched to the Moon. Surveyor 1, launched on May 30, successfully landed on Oceanus Procellarum on June 2, becoming the first automated soft-landing spacecraft to explore the Moon. Surveyor 1 was equipped to respond to commands from Earth and to transmit scientific and engineering data from the lunar surface. It was a technological triumph for the United States and a good beginning for lunar exploration. Surveyor 2, launched on September 20, was not so lucky; it crashed near the huge Moon crater Copernicus on September 22.
Next in line was Surveyor 3. Launched on April 17, 1967, it landed on Oceanus Procellarum on April 19. After surviving a three-bounce landing, Surveyor 3 became the first spacecraft to carry a surface soil-sampling scoop when its motor-driven arm was used to dig four trenches in the lunar soil and retrieve soil and rock samples for a detailed inspection by its camera. Ronald F. Scott was the lead investigator for this project. Surveyor 3 is also remembered because it was visited in 1969 by Apollo 12 astronauts Pete Conrad and Alan L. Bean, who landed their spacecraft within walking distance of Surveyor and retrieved several of Surveyor’s components for further study.
Under sterile laboratory conditions on Earth, technicians found the presence of Streptococcus mitis, common bacteria, in the spacecraft’s camera. The bacteria had been unintentionally present at launch and survived almost three years in the harsh lunar environment, prompting scientists to review existing prelaunch decontamination procedures and to rethink theories about the possibility of extraterrestrial life in space. Surveyor 4, launched on July 14, did not build upon the success of its predecessor; it crashed into Sinus Medii on July 17.
The next mission saw Surveyor 5, launched on September 8, successfully land on September 11 on the plains of Mare Tranquillitatis, a site similar to the spot where Apollo 11 would land in 1969. The systematic survey of possible Apollo landing sites continued with Surveyor 6, which was launched on November 7 and landed on Sinus Medii on November 10. Surveyor 7 would be a departure from the preceding four successful landings, which all occurred on the relatively flat lunar surface. This mission targeted the rough terrain and debris fields surrounding the young impact crater Tycho. Surveyor 7 was launched on January 7, 1968, and landed on the rim of Tycho on January 10. This final Surveyor mission ended on February 21, with its deactivation. With the success of Surveyor 7, the path was clear for a successful piloted lunar landing.
Significance
The Surveyor program was a necessary and significant first step to the Moon. Five of seven Surveyor spacecraft made successful landings and returned a wealth of scientific and engineering data, which directly contributed to the success of the Apollo missions. Four of the Surveyors landed on the lunar maria near the Moon’s equator, at sites selected, primarily, to evaluate potential landing spots for the Apollo astronauts (astronaut safety was a primary concern). The maria had been determined to be relatively flat and crater-free, and would offer the astronauts the best chance for a successful landing. Secondary in importance was the research of the missions.
Surveyor 7 would depart from its scientific role when it landed in the highlands region near the great impact crater Tycho, proving that the technology existed to land in very rugged terrain. Because of the combined data gathered by the Surveyor and Lunar Orbiter programs, Apollo 14 and later missions would be able to explore more challenging locations. In addition, the scientific experiments performed on the Moon by Surveyor provided scientists with their first hands-on look at the surface material of a place beyond Earth. They offered answers to many basic geological questions and raised many more questions, which could be answered only by bringing back to Earth actual samples from the Moon.
Bibliography
Hartmann, William K. Moons and Planets. 5th ed. Belmont, Calif.: Brooks/Cole, 2005. Provides detailed information about all objects in the solar system. Suitable on three separate levels: high school students, general readers, and college undergraduates studying planetary geology.
Long, Kim. The Moon Book: Fascinating Facts About the Magnificent, Mysterious Moon. Boulder, Colo.: Johnson Books, 1998. A “manual” of sorts that provides easy reading on Moon facts.
Mirabito, Michael. The Exploration of Outer Space with Cameras: A History of the NASA Unmanned Spacecraft Missions. Jefferson, N.C.: McFarland, 1983. A comprehensive work that is well illustrated and includes discussion of the Surveyor and Lunar Orbiter programs.
Siddiqi, Asif A. Deep Space Chronicle: Robotic Exploration Missions to the Planets. NASA SP-2002-4524. Washington, D.C.: National Aeronautics and Space Administration, 2002. This publication offers readers a good reference to planetary missions, including the Surveyor and Lunar Orbiter programs.
Ulivi, Paolo, and David M. Harland. Lunar Exploration: Human Pioneers and Robotic Surveyors. New York: Springer Praxis, 2004. Chapter 2 provides a good review of the Surveyor program in the context of the Ranger and Lunar Orbiter programs.
Wilhelms, Don E. To a Rocky Moon: A Geologist’s History of Lunar Exploration. Tucson: University of Arizona Press, 1993. A comprehensive book, written from a geologist’s point of view, covering the history of lunar exploration. Chapter 8 describes the Surveyor program in detail and examines its contributions to an overall understanding of the Moon.