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Lunar Orbiter 3

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Lunar Orbiter 3
Lunar Orbiter 3 image of the Moon, enhanced by LOIRP
Mission typeLunar orbiter
COSPAR ID1967-008A Edit this at Wikidata
SATCAT no.2666
Mission duration246 days
Spacecraft properties
ManufacturerLangley Research Center
Launch mass385.6 kilograms (850 lb)[1]
Start of mission
Launch dateFebruary 5, 1967, 01:17:01 (1967-02-05UTC01:17:01Z) UTC[1]
RocketAtlas SLV-3 Agena-D
Launch siteCape Canaveral LC-13
End of mission
Decay dateOctober 9, 1967 (1967-10-10)
Orbital parameters
Reference systemSelenocentric
Semi-major axis2,694 kilometers (1,674 mi)
Periselene altitude1,791 kilometers (1,113 mi)
Aposelene altitude3,598 kilometers (2,236 mi)
Inclination20.9 degrees
Period208.1 minutes
EpochFebruary 7, 1967, 19:00:00 UTC[2]
Lunar orbiter
Orbital insertionFebruary 8, 1967, 21:54 UTC
Impact site14°18′N 97°42′W / 14.3°N 97.7°W / 14.3; -97.7

The Lunar Orbiter 3 was a spacecraft launched by NASA in 1967 as part of the Lunar Orbiter Program.[3] It was designed primarily to photograph areas of the lunar surface for confirmation of safe landing sites for the Surveyor and Apollo missions. It was also equipped to collect selenodetic, radiation intensity, and micrometeoroid impact data.

Mission summary[edit]

The spacecraft was placed in a cislunar trajectory and injected into an elliptical near-equatorial lunar orbit on February 8 at 21:54 UT. The orbit was 210.2 by 1,801.9 kilometres (130.6 mi × 1,119.6 mi) with an inclination of 20.9 degrees and a period of 3 hours 25 minutes. After four days (25 orbits) of tracking the orbit was changed to 55 by 1,847 kilometres (34 mi × 1,148 mi). The spacecraft acquired photographic data from February 15 to 23, 1967, and readout occurred through March 2, 1967. The film advance mechanism showed erratic behavior during this period resulting in a decision to begin readout of the frames earlier than planned. The frames were read out successfully until March 4 when the film advance motor burned out, leaving about 25% of the frames on the takeup reel, unable to be read.

A total of 149 medium resolution and 477 high resolution frames were returned.[4] The frames were of excellent quality with resolution down to 1 metre (3 ft 3 in). Included was a frame of the Surveyor 1 landing site, permitting identification of the location of the spacecraft on the surface. The future landing site of Apollo 14 including Cone crater, was photographed by the orbiter.[5] Accurate data were acquired from all other experiments throughout the mission.[6] The spacecraft was used for tracking purposes until it struck the lunar surface on command at 14.3 degrees N latitude, 97.7 degrees W longitude (selenographic coordinates) on October 9, 1967.

Spacecraft orbit and photographic coverage on the near side (left) and far side (right)
Lunar Photographic Studies : Evaluation of Apollo and Surveyor landing sites
Detectors :
Detection of micrometeoroids in the lunar environment
Caesium Iodide Dosimeters : Radiation environment en route to and near the Moon
Selenodesy : Gravitational field and physical properties of the Moon

See also[edit]


  1. ^ a b Siddiqi, Asif (2018). Beyond Earth: A Chronicle of Deep Space Exploration, 1958–2016 (PDF) (second ed.). NASA History Program Office.
  2. ^ "NASA - NSSDCA - Spacecraft - Trajectory Details". nssdc.gsfc.nasa.gov. Retrieved 2018-05-02.
  3. ^ "Destination Moon: A history of the Lunar Orbiter Program". NASA. 1976. Retrieved 2022-11-12.
  4. ^ "Lunar Orbiter Photo Gallery – Mission 3". Lunar and Planetary Institute. Retrieved 2022-11-13.
  5. ^ Apollo 14 Preliminary. Science Report, NASA Special Publication 272 (SP-272), 1971. Prepared by NASA Manned Spacecraft Center. Scientific and Technical information Office, Washington, D.C.
  6. ^ Hansen, Thomas P. "Guide to Lunar Orbiter Photographs" (PDF). NASA. Retrieved 2022-11-13.