Lunar Orbiter 4

Lunar Orbiter 4
Image taken by Lunar Orbiter 4, showing the Moon with a crescent Earth in the background. Enhanced by LOIRP.
Mission typeLunar orbiter
OperatorNASA
COSPAR ID1967-041A Edit this at Wikidata
SATCAT no.2772
Mission duration180 days
Spacecraft properties
ManufacturerLangley Research Center
Launch mass385.6 kilograms (850 lb)[1]
Start of mission
Launch dateMay 4, 1967, 22:25:00 (1967-05-04UTC22:25Z) UTC[1]
RocketAtlas SLV-3 Agena-D
Launch siteCape Canaveral LC-13
End of mission
Last contactJuly 17, 1967 (1967-07-18)[1]
Decay dateOctober 6, 1967[1]
Orbital parameters
Reference systemSelenocentric
Semi-major axis6,152.5 kilometers (3,823.0 mi)
Eccentricity0.28
Periselene altitude4,449 kilometers (2,764 mi)
Aposelene altitude7,856 kilometers (4,881 mi)
Inclination85.5 degrees
Period721 minutes
EpochMarch 7, 1967, 20:00:00 UTC[2]
Lunar orbiter
Orbital insertionMay 8, 1967, 21:54 UTC
Orbits360

Lunar Orbiter 4 was a robotic U.S. spacecraft, part of the Lunar Orbiter Program,[3] designed to orbit the Moon, after the three previous 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".[2] It was also equipped to collect selenodetic, radiation intensity, and micrometeoroid impact data.

  1. ^ a b c d Siddiqi, Asif A. (2018). Beyond Earth A Chronicle of Deep Space Exploration, 1958–2016 (PDF). NASA. ISBN 9781626830431. LCCN 2017058675. SP-2018-4041. Archived (PDF) from the original on June 12, 2024.
  2. ^ a b "Lunar Orbiter 4". NSSDCA Master Catalog. NASA. Archived from the original on May 24, 2024. Retrieved May 2, 2018.
  3. ^ Byers, Bruce K. (April 1977). Destination MOON: A History of the Lunar Orbiter Program (PDF) (Technical report). NASA. hdl:2060/19770016195. TM X-3487. Archived (PDF) from the original on August 17, 2024. Retrieved November 12, 2022.