| Kosmos 48 | |
| Names List: | Zenit 2-23 |
| Mission Type: | Optical imaging reconnaissance |
| Operator: | OKB-1 |
| Cospar Id: | 1964-066A |
| Satcat: | 908 |
| Mission Duration: | 6 days |
| Spacecraft Type: | Zenit-2 |
| Manufacturer: | OKB-1 |
| Launch Mass: | 4730 kg[1] |
| Launch Date: | 14 October 1964 09:50:00 GMT |
| Launch Rocket: | Vostok-2 |
| Launch Site: | Baikonur 31/6 |
| Disposal Type: | Recovered |
| Landing Date: | 20 October 1964 |
| Orbit Epoch: | 14 October 1964 |
| Orbit Reference: | Geocentric[2] |
| Orbit Regime: | Low Earth |
| Orbit Periapsis: | 204 km |
| Orbit Apoapsis: | 284 km |
| Orbit Inclination: | 65.1° |
| Orbit Period: | 89.4 minutes |
| Apsis: | gee |
| Programme: | Zenit programme Zenit-2 |
| Previous Mission: | Zenit 2-22 |
| Next Mission: | Zenit 2-24 |
| Programme2: | Kosmos (satellites) |
| Previous Mission2: | Kosmos 47 |
| Next Mission2: | Kosmos 49 |
Kosmos 48 (Russian: Космос 48 meaning Cosmos 48) or Zenit-2 No.23 was a Soviet, first generation, low resolution, optical film-return reconnaissance satellite launched in 1964. A Zenit-2 spacecraft, Kosmos 48 was the twenty-third of eighty-one such satellites to be launched[3] and had a mass of 4730kg (10,430lb).
Kosmos 48 was launched by a Vostok-2 rocket, serial number R15002-01,[4] flying from Site 31/6 at the Baikonur Cosmodrome. The launch took place at 09:50 GMT on 14 October 1964, and following its successful arrival in orbit the spacecraft received its Kosmos designation; along with the International Designator 1964-066A and the Satellite Catalog Number 00908.
Kosmos 48 was operated in a low Earth orbit; on 14 October 1964 it had a perigee of 204km (127miles), an apogee of 284km (176miles), inclination of 65.1° and an orbital period of 89.4 minutes. Midway through its planned reconnaissance mission, the thermal control system malfunctioned, with the temperature inside the spacecraft's pressurised capsule increasing to 43 °C. As a result of the malfunction, the spacecraft was deorbited two days earlier than planned, on 20 October 1964, six days after launch.[5] The return capsule, containing the cameras and film, was successfully recovered by parachute for recovery by Soviet forces.[6]