Kosmos 78 (Russian: Космос 78, romanized: Cosmos 78) or Zenit-2 No.30 was a Soviet, first generation, low resolution, optical film-return reconnaissance satellite launched in 1965. A Zenit-2 spacecraft, Kosmos 78 was the thirtieth of eighty-one such satellites to be launched^[4][5] and had a mass of 4,730 kilograms (10,430 lb).

Kosmos 78

Mission type	Optical imaging reconnaissance
Operator	OKB-1
COSPAR ID	1965-066A
SATCAT no.	01505
Mission duration	8 days
Spacecraft properties
Spacecraft type	Zenit-2
Manufacturer	OKB-1
Launch mass	4730 kg[1]
Start of mission
Launch date	14 August 1965 11:17:00 GMT[2]
Rocket	Vostok-2 s/n U15001-02
Launch site	Baikonur, Site 31/6
Contractor	OKB-1
End of mission
Disposal	Recovered
Landing date	22 August 1965
Orbital parameters
Reference system	Geocentric[3]
Regime	Low Earth
Perigee altitude	218 km
Apogee altitude	298 km
Inclination	69.0°
Period	89.9 minutes
Epoch	14 August 1965

Kosmos 78 was launched by a Vostok-2 rocket, serial number U15001-02,^[6] flying from Site 31/6 at the Baikonur Cosmodrome. The launch took place at 11:17 GMT on 14 August 1965, and following its successful arrival in orbit the spacecraft received its Kosmos designation; along with the International Designator 1965-066A and the Satellite Catalog Number 01505.

Kosmos 78 was operated in a low Earth orbit; at an epoch of 14 August 1965, it had a perigee of 218 kilometres (135 mi), an apogee of 298 kilometres (185 mi), an inclination of 69.0° and an orbital period of 89.9 minutes. On 22 August 1965, after eight days of operation the satellite was deorbited, with its return capsule descending by parachute for recovery by Soviet force.^[7]