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Lunar Orbiter

Lunar Orbiter
Lunar Orbiter
first photo of the Earth from the Moon, sent back by Lunar Orbiter 1
First photo of the Earth from the Moon, sent back by Lunar Obiter 1 on Aug. 23, 1966
Lunar Orbiter was 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 meters 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

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    • Moon, unmanned spacecraft

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