| Kosmos 35 | |
| Names List: | Zenit 2-20 |
| Mission Type: | Optical imaging reconnaissance |
| Operator: | OKB-1 |
| Cospar Id: | 1964-039A |
| Satcat: | 833 |
| Mission Duration: | 8 days |
| Spacecraft Type: | Zenit-2 |
| Manufacturer: | OKB-1 |
| Launch Mass: | 4730 kg[1] |
| Launch Date: | 15 July 1964, 11:31:00 GMT |
| Launch Rocket: | Vostok-2 |
| Launch Site: | Baikonur 31/6 |
| Launch Contractor: | OKB-1 |
| Disposal Type: | Recovered |
| Landing Date: | 23 July 1964 |
| Orbit Epoch: | 15 July 1964 |
| Orbit Reference: | Geocentric[2] |
| Orbit Regime: | Low Earth |
| Orbit Periapsis: | 218 km |
| Orbit Apoapsis: | 258 km |
| Orbit Inclination: | 51.3° |
| Orbit Period: | 89.2 minutes |
| Apsis: | gee |
| Programme: | Zenit programme Zenit-2 |
| Previous Mission: | Zenit 2-19 |
| Next Mission: | Zenit 2-21 |
| Programme2: | Kosmos (satellites) |
| Previous Mission2: | Kosmos 34 |
| Next Mission2: | Kosmos 36 |
Kosmos 35 (Russian: Космос 35 meaning Cosmos 35) or Zenit-2 No.20 was a Soviet, first generation, low resolution, optical film-return reconnaissance satellite launched in 1964. A Zenit-2 spacecraft, Kosmos 35 was the twentieth of eighty-one such satellites to be launched[3] and had a mass of 4730kg (10,430lb).
Kosmos 35 was launched by a Vostok-2 rocket, serial number R15001-03,[4] flying from Site 31/6 at the Baikonur Cosmodrome. The launch took place at 11:31 GMT on 15 July 1964,[5] and following its successful arrival in orbit the spacecraft received its Kosmos designation; along with the International Designator 1964-039A and the Satellite Catalog Number 00833.[6]
Kosmos 35 was operated in a low Earth orbit, it had a perigee of 218km (135miles), an apogee of 258km (160miles), inclination of 51.3° and an orbital period of 89.2 minutes. On 23 July 1964, after eight days in orbit, the satellite was deorbited with its return capsule descending by parachute for recovery by Soviet forces.[7] [8]