Kosmos 138

Kosmos 138 (Космос 138 meaning Cosmos 138) or Zenit-2 No.43 was a Soviet, first generation, low resolution, optical film-return reconnaissance satellite launched in 1967. A Zenit-2 spacecraft, Kosmos 138 was the forty-fifth of eighty-one such satellites to be launched and had a mass of 4730 kg.

Kosmos 138 was launched by a Vostok-2 rocket, serial number N15001-05, flying from Site 41/1 at the Plesetsk Cosmodrome. The launch took place at 12:39:59 GMT on 19 January 1967, and following its arrival in orbit the spacecraft received its Kosmos designation; along with the International Designator 1967-004A and the Satellite Catalog Number 02646. The satellite reached a slightly lower orbit than had been planned, but was still able to complete its mission.

Kosmos 138 was operated in a low Earth orbit, at an epoch of 19 January 1967, it had a perigee of 191 km, an apogee of 273 km, an inclination of 65.0°, and an orbital period of 89.2 minutes. After 8 days in orbit, Kosmos 138 was deorbited, with its return capsule descending under parachute, landing at 06:14 GMT on 27 January 1967, and recovered by Soviet force.