Luna 18

Luna 18
A Ye-8-5 model in the Museum of Cosmonautics, Moscow.
Mission typeLunar sample return
OperatorSoviet space program
COSPAR ID1971-073A
SATCAT no.5448
Mission duration9 days (launch day to day of last contact)
Spacecraft properties
BusYe-8-5
ManufacturerGSMZ Lavochkin
Launch mass5,725 kilograms (12,621 lb)
Dry mass5,600 kilograms (12,300 lb)
Start of mission
Launch date2 September 1971, 13:40:40 (1971-09-02UTC13:40:40Z) UTC
RocketProton-K/D
Launch siteBaikonur 81/24
End of mission
Last contact11 September 1971, 07:48 (1971-09-11UTC07:49Z) UTC
Orbital parameters
Reference systemSelenocentric
Eccentricity0.001361
Periselene altitude1,824.9 kilometres (1,133.9 mi)
Aposelene altitude1,842.3 kilometres (1,144.8 mi)
Inclination35 degrees
Period119 minutes
Epoch6 September 1971, 20:00:00 UTC
Lunar orbiter
Orbital insertion7 September 1971
Orbits54
Lunar impact (failed landing)
Impact date11 September 1971 07:48 UTC
Impact site3°34′N 56°30′E / 3.567°N 56.500°E / 3.567; 56.500
Instruments
Stereo photographic imaging system
Remote arm for sample collection
Radiation detector
Radio altimeter

Luna 18, part of the Ye-8-5 series, was an uncrewed space mission of the Luna program.