Luna 22

Launch data:

Designation	07315 / 74037A
Launch date	29 May 1974 - 08:56:51 UT
Launch site	B, LC-81/24
Launch vehicle	Proton-K/D 8K82K (#282-02/11S24)
Satellite type	Ye-8-LS N° 206 (#2)
Mission	Lunar Orbiter
Selenocentric (Moon) orbit on 1974 Jun 2.7:
Periselene / Aposelene	219 x 221 km
Eccentricity	0.0
Inclination	19.58 deg
Period	130 min
Selenocentric (Moon) orbit on 1974 Nov 11.63:
Periselene / Aposelene	171 x 1437
Eccentricity	0.248
Inclination	19.55 deg
Period	192 min
Selenocentric (Moon) orbit on 1975 Sep 3.4:
Periselene / Aposelene	100 x 1286
Eccentricity	0.244
Inclination	21 deg
Period	179 min

Heavy lunar orbiter. Scientific investigation of the moon and circumlunar space from the orbit of an artificial satellite of the Moon, which was begun by the Luna 19 automatic station. The spacecraft carried imaging cameras and also had the objectives of studying the Moon's magnetic field, surface gamma ray emissions and composition of lunar surface rocks, and the gravitational field, as well as micrometeoroids and cosmic rays.
Luna 22 braked into a circular lunar orbit on 2 June 1974. The spacecraft made many orbit adjustments over its 18 month lifetime in order to optimise the operation of various experiments, lowering the perilune to as low as 25 km. Manoeuvring fuel was exhausted on 2 September 1975 and the mission was ended in early November.

Ref.: #1, #7, #8, #14, #206 - update: 24.11.10