View source for Venera 1

{{Short description|Soviet space probe launched in 1961; first spacecraft to fly by Venus}}
{{italic title}}
{{Infobox spaceflight
| name               = ''Venera 1''
| image              = Venera_1_(a)_(Memorial_Museum_of_Astronautics).JPG
| image_caption      = Mockup of the ''Venera 1'' spacecraft
| mission_type       = [[Venus]] impactor
| operator           = [[OKB-1]]
| Harvard_designation = 1961 Gamma 1
| COSPAR_ID          = 1961-003A
| SATCAT             = 80
| mission_duration   = 7 days
| spacecraft         = [[1MV|1VA No.2]]
| manufacturer       = [[OKB-1]]
| launch_mass        = {{convert|6,424.0|kg|lb}}
| dry_mass           = {{convert|643.5|kg|lb}}
| landing_mass       = 
| power              = <!-- [[watt]]s -->
| launch_date        = {{start-date|February 12, 1961, 00:34:36|timezone=yes}}&nbsp;UTC
| launch_rocket      = [[Molniya (rocket)|Molniya 8K78]]
| launch_site        = [[Baikonur Cosmodrome|Baikonur]] [[Baikonur Cosmodrome Site 1|1/5]]
| last_contact       = {{end-date|19 February 1961}}
| orbit_epoch        = 
| orbit_reference    = [[Heliocentric orbit|Heliocentric]]
| orbit_periapsis    = 0.718 [[Astronomical unit|AU]]
| orbit_apoapsis     = 1.019 AU
| orbit_eccentricity = 0.173
| orbit_inclination  = 0.58°
| orbit_period       = 311 days
| apsis              = helion
| interplanetary     = {{Infobox spaceflight/IP
   |type                = flyby
   |object              = [[Venus]] 
   |arrival_date        = 19 May 1961
   |distance            = {{convert|100000|km|mi|abbr=on}}
 }}
| insignia           = The Soviet Union 1961 CPA 2556 stamp (Launching of the Venus space probe, 1961-2-12. Globe and Venera 1).jpg
| insignia_size      = 80px
| insignia_caption   = 
| programme          = [[Venera program|Venera]]
| previous_mission   = [[Tyazhely Sputnik]]
| next_mission       = [[Venera 2MV-1 No.1]]
}}

'''''Venera 1''''' ({{langx|ru|Венера-1}} meaning ''Venus 1''), also known as '''Venera-1VA No.2''' and occasionally in the West as '''''Sputnik 8''''', was the first spacecraft to perform an [[interplanetary flight]] and the first to fly past [[Venus]], as part of the [[Soviet Union]]'s [[Venera]] programme.<ref name=":0">{{Cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1961-003A|title=Venera 1|website=NASA Space Science Data Coordinated Archive|access-date=2019-08-15|archive-date=2020-11-26|archive-url=https://web.archive.org/web/20201126124517/https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1961-003A|url-status=dead}}</ref> Launched in February 1961, it was intended as an impactor, but flew past Venus on 19 May of the same year; however, radio contact with the [[Space probe|probe]] was lost before the [[Flyby (spaceflight)|flyby]], resulting in it returning no data.

==Spacecraft==
''Venera 1'' was a {{convert|643.5|kg|adj=on}} probe consisting of a cylindrical body {{convert|1.05|m}} in diameter topped by a dome, totalling {{convert|2.035|m}} in height. This was pressurized to {{convert|1.2|atm}} with dry nitrogen, with internal fans to maintain even distribution of heat.{{citation needed|date=January 2013}} Two solar panels extended from the cylinder, charging a bank of [[silver-zinc battery|silver-zinc batteries]]. A {{convert|2|m|adj=on}} parabolic wire-mesh antenna was designed to send data from Venus to Earth on a frequency of 922.8&nbsp;MHz. A {{convert|2.4|m|adj=on}} antenna boom was used to transmit short-wave signals during the near-Earth phase of the mission. Semidirectional [[quadrupole]] antennas mounted on the solar panels provided routine telemetry and telecommand contact with Earth during the mission, on a circularly-polarized decimetre radio band.

The probe was equipped with scientific instruments including a flux-gate [[magnetometer]] attached to the antenna boom, two [[ion trap]]s to measure solar wind, [[micrometeorite]] detectors, and [[Geiger counter]] tubes and a sodium iodide [[scintillator]] for measurement of cosmic radiation. An experiment attached to one solar panel measured temperatures of experimental coatings. Infrared and/or ultraviolet radiometers may have been included. The dome contained a [[KDU-414]] engine used for mid-course corrections. Temperature control was achieved by motorized thermal shutters.

During most of its flight, ''Venera 1'' was spin stabilized. It was the first spacecraft designed to perform mid-course corrections, by entering a mode of 3-axis stabilization, fixing on the Sun and the star [[Canopus]]. Had it reached Venus, it would have entered another mode of 3-axis stabilization, fixing on the [[Sun]] and [[Earth]], and using for the first time a parabolic antenna to relay data.

==Launch==
[[File:The Soviet Union 1961 CPA 2557A stamp (Launching of the Venus space probe, 1961-2-12. Space probe and its path to Venus).jpg|thumb|Route of Venera 1 on a Soviet stamp]]
''Venera 1'' was the second of two attempts to launch a probe to Venus in February 1961, immediately following the launch of its sister ship [[Tyazhely Sputnik|''Venera-1VA No.1'']],<ref name= "Chronology">NSSDC [http://nssdc.gsfc.nasa.gov/planetary/chronology_venus.html Chronology of Venus Exploration] {{Webarchive|url=https://web.archive.org/web/20150730111434/http://nssdc.gsfc.nasa.gov/planetary/chronology_venus.html |date=2015-07-30 }} (NASA Goddard Space Center), accessed August 9, 2010</ref> which failed to leave Earth orbit due to the failure of a power transformer. The transformer was wrapped in foil and painted black and white for thermal reasons.<ref>https://habr.com/ru/articles/555132/</ref><ref name="Soviet Failures">NSSDC [http://nssdc.gsfc.nasa.gov/planetary/tent_launch.html Tentatively Identified (Soviet) Missions and Launch Failures] (NASA Goddard Space Center), accessed August 9, 2010</ref> Soviet experts launched Venera-1 using a [[Molniya (rocket)|Molniya]] carrier rocket from the [[Baikonur Cosmodrome]]. The launch took place at 00:34:36 GMT on 12 February 1961. Vehicle L1-6V steered downrange into a clear blue winter sky and orbit was successfully achieved.<ref>{{cite web |url=http://planet4589.org/space/log/launchlog.txt|title=Launch Log|first=Jonathan|last=McDowell|access-date=3 January 2013|work=Jonathan's Space Page}}</ref>

The spacecraft, along with the rocket's [[Blok-L]] upper stage, was initially placed into a {{convert|229|×|282|km|adj=on}} [[low Earth orbit]],<ref name=":0"/> before the upper stage fired to place "Venera 1" into a [[heliocentric orbit]], directed towards Venus. The 11D33 engine was the world's first staged-combustion-cycle rocket engine, and also the first use of an [[ullage engine]] to allow a liquid-fuel rocket engine to start in space.

==Failure==
During the first telemetry session, it was found that Venera 1 failed to enter the constant solar orientation mode, which led to a shortage of electrical power on board. While unfortunate, this was expected and in such a case the station had to conduct a rough orientation to the Sun and turn off non-vital systems. However, the radio transmitters had not been adequately designed and communication was shortly lost. The signal was regained on 17 February but it was still unable to lock onto the Sun properly and again went into protective mode and turned off the transmitter. Three successful telemetry sessions were conducted, gathering solar-wind and cosmic-ray data near Earth, at the Earth's [[magnetopause]], and on  February 19 at a distance of {{convert|1,900,000|km|mi|abbr=on}}. After discovering the [[solar wind]] with ''Luna 2'', ''Venera 1'' provided the first verification that this plasma was uniformly present in deep space. Seven days later, the next scheduled telemetry session failed to occur.  On May 19, 1961, ''Venera 1'' passed within {{convert|100,000|km|mi|abbr=on}} of Venus. With the help of the British radio telescope at [[Jodrell Bank]], some weak signals from ''Venera 1'' may have been detected in June. Soviet engineers believed that ''Venera 1'' failed due to the overheating of a solar-direction sensor.<ref name=":1">{{Cite web|url=https://www.edn.com/venera-1-launches-toward-venus-february-12-1961/|title=Venera 1 launches toward Venus, February 12, 1961|website=AspenCore, Inc|access-date=2020-06-06}}</ref>

==See also==
{{Portal|Spaceflight}}
*[[List of missions to Venus]]
*[[Mariner 2]]
*[[Timeline of planetary exploration]]

== References ==
{{reflist}}

== External links ==
{{commonscat|Venera 1}}
*[http://www.mentallandscape.com/V_Venus.htm The Soviet Exploration of Venus]
*[https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1961-003A NSSDC Master Catalog – ''Venera 1''] {{Webarchive|url=https://web.archive.org/web/20201126124517/https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1961-003A |date=2020-11-26 }}

{{Venera}}
{{Venus spacecraft}}
{{Orbital launches in 1961}}

{{DEFAULTSORT:Venera 01}}
[[Category:Venera program]]

[[Category:Spacecraft launched in 1961]]
[[Category:Derelict space probes]]
[[Category:Derelict satellites in heliocentric orbit]]
[[Category:1961 in the Soviet Union]]
[[Category:1MV]]