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] Kosmos 611 was successfully launched into low Earth orbit at 09:29:58 UTC on 28 November 1973.

[2] The launch took place from Site 133/1 at the Plesetsk Cosmodrome,[3] and used a Kosmos-2I 63SM carrier rocket.

[4] The North American Aerospace Defense Command assigned it the catalogue number 06952.

[6] It remained in orbit until it decayed and reentered the atmosphere on 19 June 1974.