SATELLITES & SPACE PROBES A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z           HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site Lunar Orbiter A series of five, highly maneuverable, Moon-orbiting NASA spacecraft, launched in 1966-67. The Lunar Orbiters’ primary mission was to obtain topographic data in the lunar equatorial region between 43° E and 56° W to help in the selection of suitable landing sites for the unmanned Surveyor and manned Apollo missions. With this objective achieved by Lunar Orbiter 3, the remaining two flights were able to carry out further photography of lunar surface features for purely scientific purposes. Altogether, 99% of the Moon was photographed with a resolution of 60 m or better. The first three missions were dedicated to imaging 20 potential lunar landing sites that had been chosen from Earth-based observations. These were flown at low-altitude, low-inclination orbits. The fourth and fifth missions were flown in high-altitude polar orbits. Lunar Orbiter 4 photographed the entire nearside and 95% of the farside; Lunar Orbiter 5 completed the farside coverage and acquired medium (20 m) and high (2 m) resolution images of 36 pre-selected areas. The Lunar Orbiters also collected data on radiation and micrometeoroids in the circumlunar region. Spacecraft Launch Imaging Mass (kg) Lunar Orbiter 1 Aug. 10, 1966 Aug. 18-19, 1966 386 Lunar Orbiter 2 Nov. 6, 1966 Nov. 18-25, 1966 390 Lunar Orbiter 3 Feb. 5, 1967 Feb. 15-23, 1967 385 Lunar Orbiter 4 May 4, 1967 May 11-26, 1967 390 Lunar Orbiter 5 Aug. 1, 1967 Aug. 6-8, 1967 389 Related entry     • Moon, unmanned spacecraft Related categories    • SATELLITES AND SPACE PROBES    • MOON TOPICS Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP