Kosmos 3 (Russian: Космос 3 meaning Cosmos 3), also known as 2MS No.1 and occasionally in the West as Sputnik 13 was a scientific research and technology demonstration satellite launched by the Soviet Union in 1962.

It was the third satellite to be designated under the Kosmos system, and the first spacecraft to be launched as part of the 2MS programme.

Its primary missions were to develop systems for future satellites, and to record data about cosmic rays and radiation.

Scientific data and measurements were relayed to Earth by multichannel telemetry systems equipped with space-borne memory units.

The launch was conducted from Mayak-2 at Kapustin Yar, and occurred at 04:04:00 GMT on 24 April 1962.