| Mission type | Early warning |
|---|---|
| COSPAR ID | 1981-031A |
| SATCATno. | 12376 |
| Mission duration | 4 years[1] |
| Spacecraft properties | |
| Spacecraft type | US-K[2] |
| Launch mass | 1,900 kilograms (4,200 lb) |
| Start of mission | |
| Launch date | 31 March 1981, 09:40 (1981-03-31UTC09:40Z) UTC |
| Rocket | Molniya-M/2BL[2] |
| Launch site | Plesetsk Cosmodrome[2][3] |
| End of mission | |
| Deactivated | 1 May 1981[1] |
| Orbital parameters | |
| Reference system | Geocentric |
| Regime | Molniya[2] |
| Perigee altitude | 637 kilometres (396 mi)[4] |
| Apogee altitude | 39,747 kilometres (24,698 mi)[4] |
| Inclination | 63.0 degrees[4] |
| Period | 718.39 minutes[4] |
Kosmos 1261 (Russian:Космос 1261 meaningCosmos 1261) was a SovietUS-K missileearly warningsatellite which was launched in 1981 as part of the Soviet military'sOko programme. The satellite was designed to identify missile launches usingoptical telescopes andinfrared sensors.[2]
Kosmos 1261 was launched fromSite 41/1 atPlesetsk Cosmodrome in the Russian SSR.[3] AMolniya-M carrier rocket with a2BL upper stage was used to perform the launch, which took place at 09:40 UTC on 31 March 1981.[3] The launch successfully placed the satellite into amolniya orbit. It subsequently received itsKosmos designation, and theinternational designator 1981-031A.[4] TheUnited States Space Command assigned it theSatellite Catalog Number 12376.[4]
Kosmos 1261 was a US-K satellite likeKosmos 862 that self-destructed in orbit, NASA believe deliberately. The spacecraft attempted to maneuverfrom its transfer orbit to an operational orbit 3 days after launch, but it appears that the maneuver was unsuccessful, and thespacecraft never became ground track-stabilized. Immediately after the maneuver some debris was detected, while additional debriswere discovered in mid-May. There may have been more than one debris event. All of the resultant debris is still in orbit.[5]
 | This article about one or more spacecraft of theSoviet Union is astub. You can help Wikipedia byexpanding it. |
