After President Kennedy's 1961 speech and the first flights of Project Mercury, NASA embarked on several science programs to prepare for a moon landing. Under the direction of Homer Newell (1915-1983), Associate Administrator of the Office of Space Science and Applications, NASA sent Ranger, Surveyor, and Lunar Orbiter spacecrafts to study the Moon between 1962 and 1968.
These robotic vehicles provided scientists and engineers with a greater understanding of interplanetary space and lunar geography and played an important role in preparing for a manned landing. Newell not only established the lunar science program and set the direction for space science at NASA, but he also spurred initiatives for communications, weather, and other scientific satellites.
To prepare for Apollo, robotic spacecraft equipped with scientific instrumentation studied the Moon from 1962 to 1968. The Ranger and Lunar Orbiter programs provided photographic coverage of the lunar surface, and Surveyor landed to sample the lunar surface. This information was of great value to scientists studying the history of the Moon and to engineers planning the Apollo program of manned lunar landings. This detailed, systematic program of research with robotic spacecraft, both in orbit and on the surface, served as a model for later exploration of the planets. Photographic coverage assisted in selection of Apollo mission landing sites while knowledge of the physical characteristics of the lunar soil assured appropriate design of the Apollo lunar module.
These were the American robotic spacecraft designed to explore the Moon:
Lunar Orbiter, 1966-1967
Project Ranger was quickly initiated in 1959 to demonstrate that America could achieve feats in space comparable to those of the Soviets. Ranger spacecraft were to carry scientific instruments and television cameras to gather information about the Moon before crashing into it.
The decision to land a man on the Moon changed the goals and schedule of the Ranger effort. The science program now had a dual purpose: to scout for landing sites for Apollo astronauts and to gather new information about the Moon.
The Ranger spacecraft gave Americans their first look at the Moon from close range. Nine Rangers were launched from 1961 through 1965. The first six failed. The spacecraft was redesigned and Rangers 7, 8, and 9 successfully transmitted more than 17,000 television pictures of the lunar surface. These images revealed details unseen by telescopes on Earth. During the last mission, the pictures were broadcast live on network television, enabling millions of viewers to witness a descent to the Moon.
A First Look at the Moon
This television picture was transmitted by Ranger 8 about two seconds before impact in the lunar Sea of Tranquility on February 20, 1965. The image, from an altitude of about 360 meters (1,200 feet), shows an area about 1.4 kilometers (0.8 mile) on a side.
Of the seven Surveyors launched from 1966 through 1968, five landed successfully. They transmitted almost 88,000 television pictures of the lunar surface back to Earth. Using the scoop on the extended arm of the spacecraft, they sampled lunar soil and performed chemical analyses of the soil and other scientific experiments. Surveyor confirmed that the lunar surface could support a landing craft and that astronauts would be able to walk on the Moon.
Surveyors 3 through 7 each carried a robotic arm and sampling scoop to test the lunar surface for hardness, collect soil samples for onboard analysis, and move instruments about on the surface of the Moon. The arm was guided from Earth, with a television camera serving as the operator's eye.
Surveyor 3 had been on the Moon for two and a half years when the Apollo 12 crew arrived in 1969. Astronauts Charles Conrad Jr. and Alan Bean removed its television camera, surface sampler, and some tubing and brought them back to Earth for analysis.
First U.S. soft-landing on the Moon (Surveyor 1)
First color pictures from the surface of the Moon (Surveyor 1)
First "dig" on an extraterrestrial body (Surveyor 3)
First color pictures of Earth from the Moon (Surveyor 3)
First on-site chemical analysis of lunar soil (Surveyor 5)
First launch from the Moon (Surveyor 6)
The Lunar Orbiters were designed to provide detailed photographs for mapping the Moon. Five Lunar Orbiters were launched in 1966 and 1967. The first three missions concentrated on potential Apollo landing sites. The last two spacecraft went into polar orbit for scientific photography of the Moon.
Each Lunar Orbiter carried a complete film processing laboratory. Both close-up and wide-angle pictures were made on 70-millimeter film, developed, scanned, and converted to electrical signals, and then transmitted to Earth. The Lunar Orbiters photographed about 95 percent of the Moon's surface from an altitude of about 45 kilometers (28 miles), revealing features as small as 0.3 meters (1 foot) in diameter.
First U.S. spacecraft to orbit the Moon
First image of the Earth from the vicinity of the Moon
First detailed pictures of the Moon's far side
First virtually complete photographic coverage of the Moon
First photo of another man-made object on the Moon (Surveyor 3 photographed by Lunar Orbiter 3)