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Kosmos 4 (Russian: Космос 4 meaning Cosmos 4), also known as Zenit-2 #2 and occasionally in the West as Sputnik 14 was the first Sovietreconnaissance satellite to successfully reach orbit. 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 carrier rockets engines shut down prematurely.
It was launched on a Vostok-K rocket, which was making its seventh flight. 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.
Kosmos 4 was placed into a low Earth orbit with a perigee of 285 kilometres (177 mi), an apogee of 317 kilometres (197 mi), 65 degrees of inclination, and an orbital period of 90.5 minutes. It conducted a four day mission, before being deorbited and landing by parachute on 29 April. The spacecraft's orientation system failed, which resulted in only partial completion of the mission. It was to be followed by another satellite in May, however this was delayed to June, and then failed to reach orbit.
Kosmos 4 was a Zenit-2 satellite, a reconnaissance satellite derived from the Vostok spacecraft used for manned flights. The next Zenit launch attempt failed, and the next launch after that successfully reached orbit as Kosmos 7.
Payloads are separated by bullets ( · ), launches by pipes ( | ). Manned flights are indicated in bold text. Uncatalogued launch failures are listed in italics. Payloads deployed from other spacecraft are denoted in brackets.