Kosmos 27 (russian: Космос 27 meaning ''Cosmos 27''), also known as Zond 3MV-1 No.3 was a space mission intended as a

Venus Venus is the second planet from the Sun. It is sometimes called Earth's "sister" or "twin" planet as it is almost as large and has a similar composition. As an interior planet to Earth, Venus (like Mercury) appears in Earth's sky never fa ...

impact probe. The spacecraft was launched by a

Molniya Molniya (Russian for ''lightning'') may refer to: * Molniya (satellite), a Soviet military communications satellite ** Molniya orbit * Molniya (explosive trap), a KGB explosive device * Molniya (rocket), a variation of the Soyuz launch vehicle * OKB ...

8K78 carrier rocket from Baikonur. The Blok L stage and probe reached Earth orbit successfully, but the

attitude control Attitude control is the process of controlling the orientation of an aerospace vehicle with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle ...

system failed to operate.

Launch

Kosmos 27 was launched at 03:24:43 GMT on 27 March 1964, atop a

8K78 s/n T15000-27 carrier rocket flying from Site 1/5 at the

Baikonur Cosmodrome The Baikonur Cosmodrome ( kk, Байқоңыр ғарыш айлағы, translit=Baiqoñyr ğaryş ailağy, ; russian: Космодром Байконур, translit=Kosmodrom Baykonur, ) is a spaceport in an area of southern Kazakhstan leased to R ...

Spacecraft

Kosmos 27 was a "third-generation" deep space planetary probes of the 3MV series of the Soviet Union. The Soviet engineers planned four types of the 3MV, the 3MV-1 (for Venus impact), 3MV-2 (for Venus flyby), 3MV-3 (for Mars impact), and 3MV-4 (for Mars flyby). The primary difference over the second-generation was vastly improved (and in many cases doubled) orientation system elements as well as improved onboard propulsion systems. While these four versions were meant to study Mars and Venus.

Mission

The probe was the first dedicated 3MV spacecraft that the Soviets launched (earlier missions had been of the test "Object-Probe" versions as Kosmos 21). It was designed to accomplish atmospheric entry into Venus followed by descent and impact. On 27 March 1964, it had a perigee of and an apogee of , with an inclination of 64.8° and an orbital period of 88.7 minutes. The spacecraft successfully reached Earth orbit but failed to leave for Venus when the Blok L upper stage malfunctioned. The upper stage lost stable attitude due to a failure in the circuit of the power supply circuit that powered the valves for the attitude control system; hence, the stage remained uncontrollable and not ready to initiate a burn to leave Earth orbit. The problem was traced to a design error, the examination of

telemetry Telemetry is the in situ data collection, collection of measurements or other data at remote points and their automatic data transmission, transmission to receiving equipment (telecommunication) for monitoring. The word is derived from the Gr ...

data found that the failure was due to a design flaw in the circuitry of the BOZ unit, which resulted in power not being transferred to the attitude control jets on the Blok L stage, rather than one related to quality control. The spacecraft burned up in Earth's atmosphere the following day, on 28 March 1964. If successful, this mission would have been given a "Venera" designation.

References

{{DEFAULTSORT:Kosmos 0027 Kosmos satellites Venera program Spacecraft launched in 1964 Spacecraft which reentered in 1964 3MV

Launch

Spacecraft

Mission

See also

References