Kosmos 686 (Russian: Космос 686 meaning Cosmos 686), also known as DS-P1-Yu No.72, was a Soviet satellite which was launched in 1974 as part of the Dnepropetrovsk Sputnik programme.

It was a 400-kilogram (880 lb) spacecraft, which was built by the Yuzhnoye Design Bureau, and was used as a radar calibration target for anti-ballistic missile tests.

[1] A Kosmos-2I 63SM carrier rocket was used to launch Kosmos 686 from Site 133/1 of the Plesetsk Cosmodrome.

[2] The launch occurred at 16:34:56 UTC on 26 September 1974, and resulted in the satellite successfully reaching low Earth orbit.

[4] The North American Aerospace Defense Command assigned it the catalogue number 07447.