Lunar Orbiter 3

Lunar Orbiter 3

Lunar Orbiter 3 image of the Moon, enhanced by LOIRP
Mission type	Lunar orbiter
Operator	NASA
COSPAR ID	1967-008A
SATCAT №	2666
Mission duration	246 days
Spacecraft properties
Manufacturer	Langley Research Center
Launch mass	385.6 kilograms (850 lb)
Start of mission
Launch date	February 5, 1967, 01:17:00 (1967-02-05UTC01:17Z) UTC
Rocket	Atlas SLV-3 Agena-D
Launch site	Cape Canaveral LC-13
End of mission
Decay date	October 9, 1967 (1967-10-10)
Orbital parameters
Reference system	Selenocentric
Semi-major axis	2,694 kilometers (1,674 mi)
Eccentricity	0.33
Periselene	1,790 kilometers (1,110 mi)
Aposelene	3,598 kilometers (2,236 mi)
Inclination	20.9 degrees
Period	208.1 minutes
Epoch	7 February 1967, 19:00:00 UTC
Lunar orbiter
Orbital insertion	February 8, 1967, 21:54 UTC
Impact site
Orbits	1,702
---- Lunar Orbiter program ← Lunar Orbiter 2 Lunar Orbiter 4 →

The Lunar Orbiter 3 was a spacecraft launched by NASA in 1967 as part of the Lunar Orbiter Program. 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.

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 February 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. 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. Accurate data were acquired from all other experiments throughout the mission. 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)

Instruments

Lunar Photographic Studies :	Evaluation of Apollo and Surveyor landing sites
Meteoroid 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

• Lunar Orbiter Image Recovery Project
• Exploration of the Moon
• Lunar Orbiter 1
• Lunar Orbiter 2
• Lunar Orbiter 4
• Lunar Orbiter 5

External links

• NSSDC Lunar Orbiter 3 page
• DESTINATION MOON: A history of the Lunar Orbiter Program (html version) 1976
• Lunar Orbiter Photo Gallery - Mission 3 at the Lunar and Planetary Institute