Mission type | Lunar sample return |
---|---|
Operator | Soviet space program |
COSPAR ID | 1971-073A |
SATCAT no. | 5448 |
Mission duration | 9 days (launch day to day of last contact) |
Spacecraft properties | |
Bus | Ye-8-5 |
Manufacturer | GSMZ Lavochkin |
Launch mass | 5,725 kilograms (12,621 lb) [1] |
Dry mass | 5,600 kilograms (12,300 lb)[ citation needed ] |
Start of mission | |
Launch date | 2 September 1971, 13:40:40 UTC [1] |
Rocket | Proton-K/D |
Launch site | Baikonur 81/24 |
End of mission | |
Last contact | 11 September 1971, 07:48 UTC |
Orbital parameters | |
Reference system | Selenocentric |
Eccentricity | 0.001361 |
Periselene altitude | 1,824.9 kilometres (1,133.9 mi) |
Aposelene altitude | 1,842.3 kilometres (1,144.8 mi) |
Inclination | 35 degrees |
Period | 119 minutes |
Epoch | 6 September 1971, 20:00:00 UTC [2] |
Lunar orbiter | |
Orbital insertion | 7 September 1971 |
Orbits | 54 [2] |
Lunar impact (failed landing) | |
Impact date | 11 September 1971 07:48 UTC |
Impact site | |
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.
Luna 18 was placed in an Earth parking orbit after it was launched and was then sent towards the Moon. On 7 September 1971, it entered lunar orbit. The spacecraft completed 85 communications sessions and 54 lunar orbits before it was sent towards the lunar surface by use of braking rockets. It impacted the Moon on 11 September 1971, at 3 degrees 34 minutes N, 56 degrees 30 minutes E (selenographic coordinates) in rugged mountainous terrain. Signals ceased at the moment of impact.
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