Kosmos 4

Kosmos 4

A Zenit reentry capsule
Names	Zenit 2-2 Sputnik 14
Mission type	Optical imaging reconnaissance
Operator	OKB-1
Harvard designation	1962 Xi 1
COSPAR ID	1962-014A
SATCAT no.	287
Mission duration	3 days (4 days planned)
Spacecraft properties
Spacecraft type	Zenit-2
Manufacturer	OKB-1
Launch mass	4610 kg[1]
Start of mission
Launch date	26 April 1962, 10:02:00 GMT
Rocket	Vostok-K
Launch site	Baikonur 1/5
Contractor	OKB-1
End of mission
Disposal	Recovered
Landing date	29 April 1962
Landing site	Steppe in Kazakhstan
Orbital parameters
Reference system	Geocentric orbit[2]
Regime	Low Earth orbit
Perigee altitude	285 km
Apogee altitude	317 km
Inclination	65.0°
Period	90.60 minutes
Zenit programme Zenit-2 ← Zenit 2-1 Zenit 2-3 →   Kosmos (satellites) ← Kosmos 3 Kosmos 5 →

Kosmos 4 (Russian: Космос 4 meaning Kosmos 4), also known as Zenit-2 No.2 and occasionally in the West as Sputnik 14 was the first Soviet reconnaissance satellite to successfully reach orbit.

Spacecraft

Kosmos 4 was a Zenit-2 satellite, a first generation, low resolution reconnaissance satellite derived from the Vostok spacecraft used for crewed flights.^[1] It was the fourth satellite to be designated under the Kosmos system, and the second Soviet attempt to launch a reconnaissance satellite, the previous attempt having failed after one of the Vostok-K engines shut down prematurely, on 11 December 1961.^[3] Kosmos 4 had a mass of 4,610 kg (10,160 lb).^[1]

Launch

It was launched on a Vostok-K rocket, which was making its seventh flight.^[4] It was the last Zenit launch to use the Vostok-K, before launches switched to the Vostok-2 starting with the next launch attempt in June 1962. The launch was conducted from Site 1/5 at the Baikonur Cosmodrome, and occurred at 10:02 GMT on 26 April 1962.^[5] Kosmos 4 was placed into a low Earth orbit with a perigee of 285 km (177 mi), an apogee of 317 km (197 mi), an inclination of 65.0°, and an orbital period of 90.60 minutes.^[2]

Mission

It conducted a four-day mission, to measure radiation before and after the U.S. nuclear tests conducted during project Starfish Prime.^[1] However, leaks from the oxygen system tanks used for the orientation system resulted in the premature return of the spacecraft after three days of flight. During most of the flight the spacecraft was uncontrollable, before being deorbited and landing by parachute on 29 April 1962, and recovered by the Soviet forces in the steppe in Kazakhstan.^[6]

The next Zenit launch attempt, scheduled for May 1962 but delayed to 1 June 1962, failed to reach orbit, but the next launch successfully reached orbit as Kosmos 7.^[3]

See also

• 1962 in spaceflight

References