Lunar Orbiter 4: Lunar Orbit – For All Moonkind Moon Registry

Mission Details

Mission Name: Lunar Orbiter 4

Mission Type: Lunar Orbiter

Operator: NASA (National Aeronautics and Space Administration)

Launching State: United States

Location: Impacted 22–30 degrees W longitude

Latitude: N/A

Longitude: -25

Launch Date: 4 May 1967, 22:25:00 UT

Landing Date: 31 October 1967

Objects on or Related to Site:
Lunar Orbiter 4

Image Source: NASA

Description

Five Lunar Orbiter missions were launched in 1966 through 1967 with the purpose of mapping the lunar surface before the Apollo landings.

All five missions were successful, and 99% of the Moon was photographed with a resolution of 60 m or better. The first three missions were dedicated to imaging 20 potential lunar landing sites, selected based on Earth-based observations. These were flown at low inclination orbits. The fourth and fifth missions were devoted to broader scientific objectives and were flown in high altitude polar orbits.

Lunar Orbiter 4 photographed the entire nearside and 95% of the farside, and Lunar Orbiter 5 completed the farside coverage and acquired medium (20 m) and high (2 m) resolution images of 36 pre-selected areas Lunar Orbiter 4’s primary mission was to contribute to a comprehensive map of the Moon.

Heritage Consideration

Lunar Orbiter 4 was flown above the Moon’s poles.

Object on or Related to Site

Object Name: Lunar Orbiter 4
Cospar: 1967-041A
Norad: N/A
Location: Precise location unknown or undisclosed.
Launch Date: 4 May 1967, 22:25:00 UT
Landing Date: 6 October 1967
Deployment: N/A
End Date: 31 October 1967
Function: Lunar imagery.
Image Source: NASA

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. The spacecraft was used for tracking purposes until it impacted the lunar surface due to the natural decay of the orbit no later than October 31, 1967, between 22–30 degrees W longitude.