| Kosmos 391 | |
| Mission Type: | ABM radar target |
| Cospar Id: | 1971-002A |
| Spacecraft Type: | DS-P1-I |
| Manufacturer: | Yuzhnoye |
| Launch Date: | UTC |
| Launch Rocket: | Kosmos-2I 63SM |
| Launch Site: | Plesetsk 133/1 |
| Orbit Reference: | Geocentric |
| Orbit Regime: | Low Earth |
| Orbit Inclination: | 70.9 degrees |
| Orbit Period: | 95.3 minutes |
| Apsis: | gee |
Kosmos 391 (ru|Космос 391 meaning Cosmos 391), also known as DS-P1-I No.11 was a satellite which was used as a radar target for anti-ballistic missile tests. It was launched by the Soviet Union in 1971 as part of the Dnepropetrovsk Sputnik programme.[1]
It was launched aboard a Kosmos-2I 63SM rocket,[2] from Site 133/1 at Plesetsk. The launch occurred at 12:00:00 UTC on 14 January 1971.[3]
Kosmos 391 was placed into a low Earth orbit with a perigee of, an apogee of, 70.9 degrees of inclination, and an orbital period of 95.3 minutes.[1] It decayed from orbit on 21 February 1971.[4]
Kosmos 391 was the tenth of nineteen DS-P1-I satellites to be launched.[1] Of these, all reached orbit successfully except the seventh.[5]