Lunar Orbiter IV Mission

Lunar Orbiter 4 was designed to take advantage of the fact that the three previous Lunar Orbiters had completed the required needs for Apollo mapping and site selection. It was given a more general objective, to “perform a broad systematic photographic survey of lunar surface features in order to increase the scientific knowledge of their nature, origin, and processes, and to serve as a basis for selecting sites for more detailed scientific study by subsequent orbital and landing 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 polar high lunar orbit for data acquisition. The orbit was 2,706 by 6,111 kilometres (1,681 3,797 mi) with an inclination of 85.5 degrees and a period of 12 hours.

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Lunar Orbiter 4 Mission

Alternate Names: Lunar Orbiter-D, 02772
Launch Date: 1967-05-04
Launch Vehicle: Atlas-Agena D
Launch Site: Cape Canaveral, United States
Mass: 385.6 kg
Nominal Power: 375.0 W
Launch/Orbital information for Lunar Orbiter 4
Experiments on Lunar Orbiter 4
Data collections from Lunar Orbiter 4
Description
Lunar Orbiter 4 was designed to take advantage of the fact that the three previous Lunar Orbiters had completed the required needs for Apollo mapping and site selection. It was given a more general objective, to “perform a broad systematic photographic survey of lunar surface features in order to increase the scientific knowledge of their nature, origin, and processes, and to serve as a basis for selecting sites for more detailed scientific study by subsequent orbital and landing 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 polar high lunar orbit for data acquisition. The orbit was 2706 km x 6111 km with an inclination of 85.5 degrees and a period of 12 hours.

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Lunar Orbiter 3 Mission

Alternate Names: Lunar Orbiter-C, 02666
Launch Date: 1967-02-05
Launch Vehicle: Atlas-Agena D
Launch Site: Cape Canaveral, United States
Mass: 385.6 kg
Nominal Power: 375.0 W
Launch/Orbital information for Lunar Orbiter 3
Experiments on Lunar Orbiter 3
Data collections from Lunar Orbiter 3
Description
The Lunar Orbiter 3 spacecraft 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 8 February at 21:54 UT. The orbit was 210.2 km x 1801.9 km 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 km x 1847 km. 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 4 March when the film advance motor burned out, leaving about 25% of the frames on the takeup reel, unable to be read.

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Lunar Orbiter Project Briefing


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From Spaceflight Revolution: “Top NASA officials listen to a LOPO briefing at Langley in December 1966. Sitting to the far right with his hand on his chin is Floyd Thompson. To the left sits Dr. George Mueller, NASA associate administrator for Manned Space Flight. On the wall is a diagram of the sites selected for the “concentrated mission.” “The most fundamental issue in the pre-mission planning for Lunar Orbiter was how the moon was to be photographed. Would the photography be “concentrated” on a predetermined single target, or would it be “distributed” over several selected targets across the moon’s surface? On the answer to this basic question depended the successful integration of the entire mission plan for Lunar Orbiter.” The Lunar Orbiter Project made systematic photographic maps of the lunar landing sites. Published in James R. Hansen, Spaceflight Revolution: NASA Langley Research Center From Sputnik to Apollo, (Washington: NASA, 1995), p. 337.

Lunar Orbiter II Mission

The Lunar Orbiter 2 spacecraft was designed primarily to photograph smooth areas of the lunar surface for selection and verification 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 for data acquisition after 92.5 hours flight time. The initial orbit was 196 by 1,850 kilometres (122 1,150 mi) at an inclination of 11.8 degrees. The perilune was lowered to 49.7 kilometres (30.9 mi) five days later after 33 orbits. A failure of the amplifier on the final day of readout, December 7, resulted in the loss of six photographs. On December 8, 1966 the inclination was altered to 17.5 degrees to provide new data on lunar gravity.

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Lunar Orbiter 2 Mission

Alternate Names: Lunar Orbiter-B, 02534
Launch Date: 1966-11-06
Launch Vehicle: Atlas-Agena D
Launch Site: Cape Canaveral, United States
Mass: 385.6 kg
Nominal Power: 375.0 W
Launch/Orbital information for Lunar Orbiter 2
Experiments on Lunar Orbiter 2
Data collections from Lunar Orbiter 2
Description
The Lunar Orbiter 2 spacecraft was designed primarily to photograph smooth areas of the lunar surface for selection and verification 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 for data acquisition after 92.5 hours flight time. The initial orbit was 196 km x 1850 km at an inclination of 11.8 degrees. The perilune was lowered to 49.7 km five days later after 33 orbits. A failure of the amplifier on the final day of readout, 7 December, resulted in the loss of six photographs. On 8 December 1966 the inclination was altered to 17.5 degrees to provide new data on lunar gravity.

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