View source for Zond 8

{{Short description|1970 Soviet test spaceflight to the Moon}}
{{Use British English|date=April 2020}}
{{Use dmy dates|date=May 2020}}
{{Infobox spaceflight
| name                  = Zond 8
| names_list            = 

<!--image of the spacecraft/mission-->
| image                 = Zond L1 drawing.svg
| image_caption         = A drawing of Zond 8 spacecraft.
| image_alt             = 
| image_size            = 175px

<!--Basic details-->
| mission_type          = Spacecraft test
| operator              = [[TsKBEM]]
| COSPAR_ID             = 1970-088A
| SATCAT                = 04591
| mission_duration      = 7 days
| distance_travelled    = 
| orbits_completed      = 

<!--Spacecraft properties-->
| spacecraft            = Soyuz 7K-L1 s/n 14 
| spacecraft_type       = [[Human spaceflight|Uncrewed version]]
| spacecraft_bus        = [[Soyuz 7K-L1]]
| manufacturer          = [[OKB-1]]

| launch_mass           = 5,375 kg <ref name="Zond 8">{{cite book|url=https://www.nasa.gov/sites/default/files/atoms/files/beyond-earth-tagged.pdf|title=Beyond Earth: A Chronicle of Deep Space Exploration, 1958–2016|last1=Siddiqi|first1=Asif|publisher=NASA History Program Office|edition=second|year=2018}}</ref>
| landing_mass          = 
| dry_mass              = 
| payload_mass          = 
| dimensions            = 
| power                 = 

<!--Launch details-->
| launch_date           = 20 October 1970<br/>19:55:39 UTC <ref name="Zond 8"/>
| launch_rocket         = [[Proton-K]] / [[Blok D]]
| launch_site           = [[Baikonur Cosmodrome]]<br/>[[Baikonur Cosmodrome|Site 81/23]]
| launch_contractor     = [[OKB-1]]

<!--end of mission-->
| disposal_type         = 
| deactivated           = 
| destroyed             = 
| last_contact          = 
| recovery_by           = Soviet recovery vessel ''Taman''
| recovery_date         = 27 October 1970 ([[Indian Ocean]])
| decay_date            = 
| landing_date          = 27 October 1970, 13:55 GMT <ref name="Zond 8"/>
| landing_site          = [[Chagos Archipelago]]<br/>(730 km at SE) <ref>{{Cite web|url=http://epizodsspace.airbase.ru/bibl/inostr-yazyki/sov-luna/sovets-luna.pdf|title=Soviet and Russian Lunar Exploration |page=314}}</ref>

<!--orbit parameters-->
| orbit_reference       = [[Geocentric orbit|Geocentric]]
| orbit_regime          = Circumlunar 
| orbit_longitude       = <!--geosynchronous satellites only-->
| orbit_periapsis       = <!--periapsis altitude--> 
| orbit_apoapsis        = <!--apoapsis altitude--> 
| orbit_inclination     = <!--orbital inclination--> 
| orbit_period          = <!--time taken to complete an orbit-->
| orbit_epoch           = <!--the date at which the orbit parameters were correct-->
| orbit_rev_number      = <!--revolution number-->
| apsis                 = gee

|interplanetary         = <!--Infobox spaceflight/IP can be called multiple times for missions with multiple targets or combined orbiter/lander missions, etc-->
 {{Infobox spaceflight/IP
   |type                = flyby
   |object              = [[Moon]]
   |orbits              = 
   |arrival_date        = 24 October 1970
   |departure_date      = 
   |location            = 
   |distance            = 1110 km
   |sample_mass         = 
   
 }}

<!--transponder parameters-->
| trans_band            = <!--Transponder frequency bands-->
| trans_frequency       = <!--specific frequencies-->
| trans_bandwidth       = <!--bandwidth-->
| trans_capacity        = <!--capacity of the transponders-->
| trans_coverage        = <!--area covered-->

<!--Only use where a spacecraft/mission is part of a clear programme of sequential missions. -->
| programme             = 
| previous_mission      =
| next_mission          =

<!--mission insignia or patch-->
| insignia              = <!--omit the "file" prefix-->
| insignia_caption      = <!--image caption-->
| insignia_alt          = <!--image alt text-->
| insignia_size         = <!--include px/em; defaults to 180px-->
}}

'''Zond 8''', also known as '''L-1 No.14''', was the last in the series of circumlunar spacecraft, a member of the Soviet [[Zond program]], designed to rehearse a piloted circumlunar flight, an uncrewed version of [[Soyuz 7K-L1]] crewed circumlunar flight spacecraft. The project was initiated in 1965 to compete with the Americans in the race to the Moon but lost its importance once three astronauts orbited the Moon on the [[Apollo 8]] mission in December 1968.

==Mission==
Zond 8 was launched on 20 October 1970, at 19:55:39 GMT by a [[Proton-K]] / [[Blok D]] launcher from Site 81/23 of the [[Baikonur Cosmodrome]], towards the [[Moon]]. Zond 8 had a mass of {{convert|5375|kg}}.<ref name="Zond 8"/> The announced objectives of Zond 8 were investigations of the Moon and circumlunar space and testing of onboard systems and units.<ref name=Zond_8>{{cite web |url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1970-088A |title=Zond 8 |publisher=[[NASA Space Science Data Coordinated Archive]] |access-date=December 5, 2022 |archive-date=10 February 2020 |archive-url=https://web.archive.org/web/20200210024732/https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1970-088A |url-status=dead }}</ref>

The spacecraft obtained photographs of Earth on 21 October from a distance of {{convert|64480|km}}. After a mid-course correction on 22 October 1970 at a distance of {{convert|250000|km}} from Earth. The spacecraft transmitted flight images of Earth for three days. Zond 8 reached the Moon without any apparent problems, circling its target on 24 October at a range of {{convert|1110|km}} and took both [[black-and-white]] and [[Color photography|color photographs]] of the lunar surface during two separate sessions.<ref name="Experiment">{{cite web|title=Zond 8: Experiments 1970-088A |url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/displayExperiment.action?spacecraftId=1970-088A|website=nssdc.gsfc.nasa.gov|publisher=NASA|date=27 February 2020|access-date=11 April 2020}}</ref> The minimum distance from the Moon during the mission was 1,120 kilometres (696 miles) from the lunar surface.<ref name=":0">{{Cite web|title=Zond-8 flies last mission of the L1 project|url=http://russianspaceweb.com/zond8.html|access-date=2021-01-05|website=russianspaceweb.com}}</ref> Scientific measurements were also obtained during the flight.<ref name="Zond 8"/>

After two mid-course corrections on the return leg, Zond 8 achieved a return trajectory over Earth's northern hemisphere instead of the standard southern approach profile, allowing Soviet ground control stations to maintain near-continuous contact with the craft. The guidance system, however, malfunctioned on the return leg, and the spacecraft performed a simple ballistic (instead of a guided) reentry into Earth's atmosphere.<ref name="Zond 8"/> The reentry was different from other reentries in the Zond program as it went over the north pole and landed in the Indian Ocean.<ref name=":0" />

Zond 8 descent module reentered the Earth's atmosphere and splashed down safely in the Indian Ocean at 13:55 GMT on 27 October 1970 at {{convert|730|km}} southeast of the Chagos Islands, {{convert|24|km}} from its original target point. The USSR recovery ship ''Taman'' was on hand to collect it and bring it back to Moscow.<ref name="Zond 8"/>

The Soviet Kremlin officials finally decided to cancel the L1 project in 1970.<ref name=":0" />

===Scientific instruments===
* Imaging system
* Solar wind collector packages

==Zond 9==
Zond 9, Soyuz 7K-L1 s/n 10, was planned but cancelled. Zond 9 was planned to launch in July 1969, carrying a crew of [[Pavel Popovich]] and [[Vitali Sevastyanov]], but never flew.<ref>[https://slideplayer.com/slide/12123170/ Soviet Manned Lunar Exploration Program]</ref>

==Zond 10==
Zond 10, Soyuz 7K-L1 s/n 15, was planned but cancelled.<ref>[https://www.globalsecurity.org/space/world/russia/lunar-l-1.htm globalsecurity.org L-1 Lunar Circumnavigation Mission]</ref>

==See also==
{{Portal|Spaceflight}}

* [[Splashdown (spacecraft landing)]]
* [[Timeline of artificial satellites and space probes]]

==References==
{{Reflist}}

==External links==
* [http://www.mentallandscape.com/C_CatalogMoon.htm Soviet Lunar Images]
* [https://archive.today/20120719105138/http://www.astronautix.com/craft/soyz7kl1.htm Astronautix.com - detailed on Soyuz 7K-L1 (Zond) program ]
* {{APOD |date=16 July 2013 |title=The Moon from Zond 8}}
*[https://www.planetary.org/space-images/c_zond08_08 Zond 8 Earthset photo] and [https://www.planetary.org/space-images/c_zond08_animation animation] on the Bruce Murray Space Image Library

{{Zond program}}
{{Moon spacecraft}}
{{N1-L3}}
{{Orbital launches in 1970}}

[[Category:Missions to the Moon]]
[[Category:Zond program]]
[[Category:1970 in the Soviet Union]]
[[Category:Spacecraft launched in 1970]]
[[Category:Spacecraft which reentered in 1970]]
[[Category:Lunar flybys]]