|Mission type||ASAT target|
|Launch mass||650 kilograms (1,430 lb)|
|Start of mission|
|Launch date||19 May 1977, 16:30UTC|
|Launch site||Plesetsk 132/2|
|Perigee altitude||985 kilometres (612 mi)|
|Apogee altitude||2,111 kilometres (1,312 mi)|
Kosmos 909 (Russian: Космос 909 meaning Cosmos 909) was a satellite which was used as a target for tests of anti-satellite weapons. It was launched by the Soviet Union in 1977 as part of the Dnepropetrovsk Sputnik programme, and used as a target for Kosmos 910 and Kosmos 918, as part of the Istrebitel Sputnikov programme.
Kosmos 909 was placed into a low Earth orbit with a perigee of 985 kilometres (612 mi), an apogee of 2,111 kilometres (1,312 mi), 65.9 degrees of inclination, and an orbital period of 117 minutes. Attempted interceptions by Kosmos 910 and 918 on 23 May and 17 June respectively failed, and as of 2009 Kosmos 909 remains in orbit.
Kosmos 909 was the fifth of ten Lira satellites to be launched, of which all but the first were successful. Lira was derived from the earlier DS-P1-M satellite, which it replaced.