Kosmos 5 (Russian: Космос 5 meaning Cosmos 5), also known as 2MS #2 and occasionally in the West as Sputnik 15 was a scientific research and technology demonstration satellite launched by the Soviet Union in 1962.

Its primary missions were to develop systems for future satellites, and to record data about artificial radiation around the Earth.

Kosmos 5 was the penultimate MS satellite to be launched, and the last to successfully reach orbit.

The last launch attempt, of a 1MS satellite, occurred on 25 October 1962, and failed to reach orbit.

[7] Kosmos 5 was among several satellites inadvertently damaged or destroyed by the Starfish Prime high-altitude nuclear test on 9 July 1962 and subsequent radiation belt.