Tags: Artificialsatellite, Satellite.
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. It had a mass of 325 kilograms (717 lb).Kosmos 257 was launched from Site 133/1 at Plesetsk atop a Kosmos-2I 63SM carrier rocket.