| Mission type | ABM radar target |
|---|---|
| COSPAR ID | 1968-107A |
| SATCAT no. | 03578 |
| Spacecraft properties | |
| Spacecraft type | DS-P1-Yu |
| Manufacturer | Yuzhnoye |
| Launch mass | 325 kilograms (717 lb) |
| Start of mission | |
| Launch date | 3 December 1968, 14:52:21 UTC |
| Rocket | Kosmos-2I 63SM |
| Launch site | Plesetsk 133/1 |
| End of mission | |
| Decay date | 5 March 1969 |
| Orbital parameters | |
| Reference system | Geocentric |
| Regime | Low Earth |
| Perigee altitude | 261 kilometres (162 mi) |
| Apogee altitude | 396 kilometres (246 mi) |
| Inclination | 70.9 degrees |
| Period | 91.10 minutes |
Kosmos 257 (Russian: Космос 257 meaning Cosmos 257), known before launch as DS-P1-Yu No.17, was a Soviet satellite which was used as a radar calibration target for tests of anti-ballistic missiles. It was built by the Yuzhnoye Design Bureau, and launched in 1968 as part of the Dnepropetrovsk Sputnik programme.[1] It had a mass of 325 kilograms (717 lb).[1]
Kosmos 257 was launched from Site 133/1 at Plesetsk,[2] atop a Kosmos-2I 63SM carrier rocket. The launch occurred on 3 December 1968 at 14:52:21 UTC, and resulted in Kosmos 257's successful deployment into low Earth orbit.[3] Upon reaching orbit, it was assigned its Kosmos designation, and received the International Designator 1968-107A.
Kosmos 257 was operated in an orbit with a perigee of 261 kilometres (162 mi), an apogee of 396 kilometres (246 mi), 70.9 degrees of inclination, and an orbital period of 91.10 minutes.[1][4] It remained in orbit until it decayed and reentered the atmosphere on 5 March 1969.[4] It was the seventeenth of seventy nine DS-P1-Yu satellites to be launched,[1] and the sixteenth of seventy two to successfully reach orbit.[5]
- ^ a b c d Wade, Mark. "DS-P1-Yu". Encyclopedia Astronautica. Archived from the original on 2 June 2012. Retrieved 11 August 2009.
- ^ McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 11 August 2009.
- ^ Wade, Mark. "Kosmos 2". Encyclopedia Astronautica. Archived from the original on 18 June 2012. Retrieved 11 August 2009.
- ^ a b McDowell, Jonathan. "Satellite Catalog". Jonathan's Space Page. Retrieved 11 August 2009.
- ^ Krebs, Gunter. "DS-P1-Yu (11F618)". Gunter's Space Page. Retrieved 11 August 2009.