Mapping the Moon: A Brief History of Lunar Cartography from Galileo to the Lunar Reconnaissance Orbiter

Mapping the Moon

A Brief History of Lunar Cartography from Galileo to the Lunar Reconnaissance Orbiter

Lunar Orbiter

NASA launched five Lunar Orbiter missions to the Moon between August 1966 and August 1967 to photograph potential landing sites for Apollo missions.

Illustration of a Lunar Orbiter spacecraft. Manufactured by Boeing, the probe measured more than 18 feet wide when its four solar panels were deployed. Image source: Gatland, Kenneth. Robot Explorers. Blandford Press, 1972. 

Lunar Orbiter Spacecraft

The Lunar Orbiter was a five-foot wide and five-foot tall spacecraft that weighed 850 pounds. Lunar Orbiters contained a dual lens Kodak-built camera with an onboard processing system that developed film, scanned the images, and transmitted them to Earth. The camera included a 610-mm high-resolution lens and an 80-mm wide-angle lens.

A high-resolution image from Lunar Orbiter 3. The photograph was taken from an altitude of approximately 31 miles. Image source: NASA Lunar Orbiter 3 photograph courtesy of Joseph Wright.

Orbiters 1, 2, & 3

The first three Lunar Orbiter missions launched between August 1966 and February 1967 atop Atlas-Agena rockets. The orbiters flew at relatively low altitudes (27 miles) along the Moon’s equator to photograph potential landing sites in what was termed the “Apollo zone of interest.” The three missions returned 840 high-resolution photographs of 20 potential landing sites. The program objective was to be able to identify 15-foot objects in the Apollo zone and four-foot objects in potential landing areas.

A section of the first edition of a lunar farside chart published by NASA in 1967. It was assembled from photographs from first four Lunar Orbiter missions and images from the Soviet Union’s Luna 3 mission. Lunar Orbiter 5 completed mapping the missing sections. Image source: United States Air Force Aeronautical Chart and Information Center. Lunar Farside Chart. NASA, 1967.

Orbiters 4 & 5

The first three Lunar Orbiter missions successfully mapped Apollo landing sites. Rather than duplicate these efforts, NASA engineers directed Lunar Orbiters 4 and 5 to map other regions of the Moon, including the far side, from a higher altitude. When the project was completed, Lunar Orbiters had mapped 99-percent of the Moon at a detail nearly 10 times better than Earth-based telescopic observations.