Kosmos 173

Kosmos 173 (Космос 173 meaning Cosmos 173), also known as DS-P1-Yu No.8 was a Soviet satellite which was used as a radar calibration target for tests of anti-ballistic missiles. It was a 325 kg spacecraft, was built by the Yuzhnoye, and launched in 1967 as part of the Dnepropetrovsk Sputnik programme.

A Kosmos-2I 63SM carrier rocket was used to launch Kosmos 173 from Site 133/1 at Plesetsk Cosmodrome. The launch occurred at 04:59:49 GMT on 24 August 1967, and resulted in Kosmos 173's successful deployment into low Earth orbit.

Kosmos 173 was operated in an orbit with a perigee of 277 km, an apogee of 480 km, an inclination of 71.0°, and an orbital period of 92.3 minutes. It remained in orbit until it decayed and reentered the atmosphere on 17 December 1967. It was the ninth of seventy nine DS-P1-Yu satellites to be launched, and the eighth of seventy two to successfully reach orbit.