Spacecraft above Moon.

Artist's concept of Lunar Orbiter at the Moon.

Goals: This spacecraft was designed to photograph parts of the lunar surface to confirm safe landing sites for Surveyor and Apollo missions, as well as conduct various measurements of the Moon and its environment.

Accomplishments: Lunar Orbiter 3 transmitted 182 images to Earth, covering 15.5 million square kilometers of the Moon's near side and 650,000 square kilometers of the far side. The photographs from Lunar Orbiters 1, 2, and 3 allowed NASA scientists to select eight preliminary landing sites for Apollo, including the sites where Apollo 11 and Apollo 12 would ultimately touch down.

5 Feb 1967: Launch
9 Oct 1967: End of Lunar Mission


Mission Type: Orbiter
Launch Vehicle: Atlas-Agena D (no. 20 / Atlas D no. 5803 / Agena D no. AD128 / 6632)
Launch Site: Eastern Test Range / launch complex 13, Cape Canaveral, USA
NASA Center: Langley Research Center
Spacecraft Mass: 385.6 kg
Spacecraft Instruments: 1) imaging system; 2) micrometeoroid detectors; and 3) radiation dosimeters
Spacecraft Dimensions: 2 m high, 5.2 m across with dish and omnidirectional antenna deployed
Spacecraft Power: Four solar panels; nickel-cadmium batteries for use in Moon's shadow
Maximum Power: 375 W
Antenna Diameter: 1 meter (high-gain antenna)
Total Cost: The five spacecraft in the Lunar Orbiter program cost about $163 million.
References:
Deep Space Chronicle: A Chronology of Deep Space and Planetary Probes 1958-2000, Monographs in Aerospace History No. 24, by Asif A. Siddiqi

National Space Science Data Center, http://nssdc.gsfc.nasa.gov/

Solar System Log by Andrew Wilson, published 1987 by Jane's Publishing Co. Ltd.


Lunar Orbiter 3 was the final Lunar Orbiter mission to study potential Apollo landing sites; further missions would be dedicated to scientific and global surveys.

The spacecraft arrived in lunar orbit on 7 February 1967. Initial orbital parameters were 200 x 1,850 kilometers at 21° inclination. During its eight-month mission, the spacecraft took 211 frames of pictures, although only 182 were actually returned to Earth because of a problem on 24 February with the motor that rewound the film.

Despite the minor glitch, Lunar Orbiter fulfilled its original mission objectives, returning images of 15.5 million square kilometers of the near side and 650,000 square kilometers of the far side.

On 30 August 1967, ground controllers commanded the vehicle to circularize its orbit to 160 kilometers in order to simulate an Apollo trajectory.

Later, on 9 October 1967, the probe was intentionally crashed onto the lunar surface at 14°36' north latitude and 91°42' west longitude. The photographs from the first three Lunar Orbiters allowed NASA scientists to pick eight preliminary landing sites for Apollo by early April 1967, including site 2 in the Sea of Tranquility, where Apollo 11 would land, and site 5 in the Ocean of Storms, where Apollo 12 (and also Surveyor 3) would disembark.

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