Kosmos 129 (russian: Космос 129 meaning ''Cosmos 129'') or Zenit-2 No.33 was a

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

, first generation, low resolution, optical film-return

reconnaissance satellite A reconnaissance satellite or intelligence satellite (commonly, although unofficially, referred to as a spy satellite) is an Earth observation satellite or communications satellite deployed for military or intelligence applications. The ...

launched in 1966. A Zenit-2 spacecraft, Kosmos 129 was the forty-second of eighty-one such satellites to be launched and had a mass of . Kosmos 129 was launched by a Vostok-2 rocket, serial number U1500-05, flying from Site 41/1 at the Plesetsk Cosmodrome. The launch took place at 12:14 GMT on 14 October 1966, and following its successful arrival in orbit the spacecraft received its Kosmos designation; along with the International Designator 1966-091A and the Satellite Catalog Number 02491. Kosmos 129 was operated in a

low Earth orbit A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never mor ...

, at an

epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided by ...

of 14 October 1966, it had a

perigee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. For example, the apsides of the Earth are called the aphelion and perihelion. General description There are two apsides in any ellip ...

of , an

apogee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. For example, the apsides of the Earth are called the aphelion and perihelion. General description There are two apsides in any ellip ...

of , an

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a Plane of reference, reference plane and the orbital plane or Axis of rotation, axis of direction of the orbiting object ...

of 65.0°, and an

orbital period The orbital period (also revolution period) is the amount of time a given astronomical object takes to complete one orbit around another object. In astronomy, it usually applies to planets or asteroids orbiting the Sun, moons orbiting planets ...

of 89.4 minutes. After seven days in orbit, Kosmos 129 was deorbited, with its return capsule descending under parachute, landing at 06:14 GMT on 21 October 1966, and recovered by Soviet force.

References

Kosmos satellites Spacecraft launched in 1966 Spacecraft which reentered in 1966 Zenit-2 satellites 1966 in the Soviet Union {{USSR-spacecraft-stub