Mission Type: Orbiter
Launch Vehicle: Proton booster plus upper stage and escape stages, 8K82K + Blok D (Proton-K no. 282-02)
Launch Site: Tyuratam (Baikonur Cosmodrome), Baikonu Cosmodrome, NIIP-5 / launch site 81P
Spacecraft Mass: 5,700 kg (about 1,900 kg in lunar orbit)
Spacecraft Instruments: 1) imaging system; 2) gamma-ray spectrometer; 3) radio-altimeter; 4) meteoroid detectors; 5) magnetometer; 6) cosmic-ray detectors; and 7) radiation detectors
References:
Deep Space Chronicle: A Chronology of Deep Space and Planetary Probes 1958-2000, Monographs in Aerospace History No. 24, by Asif A. Siddiqi

National Space Science Data Center, http://nssdc.gsfc.nasa.gov/

Solar System Log by Andrew Wilson, published 1987 by Jane's Publishing Co. Ltd.

Luna 22 was the second of two "advanced" lunar orbiters (the first being Luna 19) designed to conduct extensive scientific surveys from orbit. Launched about a year after the termination of Lunokhod 2 operations on the lunar surface, Luna 20 performed a single midcourse correction en route the Moon on 30 May before entering lunar orbit on 2 June 1974. Initial orbital parameters were 219 x 222 kilometers at 19°35' inclination.

In addition to its primary mission of surface photography, Luna 22 also performed investigations to determine the chemical composition of the lunar surface, recorded meteoroid activity, searched for a lunar magnetic field, measured solar and cosmic radiation flux, and continued studies of the irregular magnetic field. Through various orbital changes, Luna 22 performed without any problems and continued to return photos 15 months into the mission, although its primary mission had ended by 2 April 1975. The spacecraft's maneuvering propellant was finally depleted on 2 September, and the highly successful mission was formally terminated in early November 1975.