|Mission type||ABM radar target|
|Mission duration||203 days|
|Launch mass||325 kg |
|Start of mission|
|Launch date||21 December 1965|
|Launch site||Kapustin Yar, Site 86/1|
|End of mission|
|Decay date||12 July 1966|
|Perigee altitude||254 km|
|Apogee altitude||539 km|
|Epoch||21 December 1965|
Kosmos 101 (Russian: Космос 101 meaning Cosmos 101), also known as DS-P1-Yu No.4 was a Soviet satellite which was used as a radar calibration target for tests of anti-ballistic missiles. It was built by the Yuzhnoye Design Bureau, and launched in 1965 as part of the Dnepropetrovsk Sputnik programme.
Kosmos 101 separated from its carrier rocket into a low Earth orbit with a perigee of 254 kilometres (158 mi), an apogee of 539 kilometres (335 mi), an inclination of 49.0°, and an orbital period of 92.4 minutes. It decayed from orbit on 12 July 1966. Kosmos 101 was the fourth of seventy nine DS-P1-Yu satellites to be launched, of which all but seven were successful.