Kosmos 307 (Russian: Космос 307 meaning Cosmos 307), known before launch as DS-P1-Yu No.22, was a Soviet satellite launched in 1969 as part of the Dnepropetrovsk Sputnik programme. It was a 250-kilogram (550 lb) spacecraft, which was built by the Yuzhnoye Design Bureau, and was used as a radar calibration target for anti-ballistic missile tests.