Kosmos 901

Kosmos 901, also known as DS-P1-I No.18 was a satellite which was used as a radar target for anti-ballistic missile tests. It was launched by the Soviet Union in 1977 as part of the Dnepropetrovsk Sputnik programme.
It was launched aboard a Kosmos-2I 63SM rocket, from Site 133/1 at Plesetsk. The launch occurred at 10:30 UTC on 5 April 1977.
Kosmos 901 was placed into a low Earth orbit with a perigee of, an apogee of, 71 degrees of inclination, and an orbital period of 95.5 minutes. It decayed from orbit on 28 June 1978.
Kosmos 901 was the eighteenth of nineteen DS-P1-I satellites to be launched. Of these, all reached orbit successfully except the seventh.