Editing Proton (satellite program) (section)

{{Short description|Series of Soviet satellites}}
{{good article}}
{{Infobox spaceflight
| name                  = {{nowrap|'' Proton 1'', ''2'', ''3'', and ''4''}}
| image                 = File:Proton1-2.gif
| image_caption         = A Proton satellite
| mission_type          = [[Astronomy]]
| operator              = [[Soviet Union]]
| COSPAR_ID             = {{plainlist|
*1965-054A  (Proton 1)
*1965-087A  (Proton 2)
*1966-060A  (Proton 3)
*1968-103A  (Proton 4)}}
| SATCAT                = 
| mission_duration      =

| spacecraft_type       = 
| manufacturer          = [[OKB-52]]
| dry_mass              = 
| launch_mass           = {{plainlist|
*{{convert|12200|kg|lb|abbr=on}} (Proton 1)
*{{convert|12200|kg|lb|abbr=on}} (Proton 2)
*{{convert|12200|kg|lb|abbr=on}} (Proton 3)
*{{convert|17000|kg|lb|abbr=on}} (Proton 4)}}
| power                 = 
| launch_date           = {{plainlist|
*'''Proton 1''': {{start-date|16 July 1965 11:16|timezone=yes}}&nbsp;UTC
*'''Proton 2''': {{start-date|2 November 1965 12:28|timezone=yes}}&nbsp;UTC
*'''Proton 3''': {{start-date|6 July 1966 12:57|timezone=yes}}&nbsp;UTC
*'''Proton 4''': {{start-date|16 November 1968 11:40|timezone=yes}}&nbsp;UTC}}
| launch_rocket         = [[UR-500]] (1–3), [[Proton-K]] (4)
| launch_site           = [[Baikonur Cosmodrome Site 81/23]] (1–3), [[Baikonur Cosmodrome Site 81/24]] (4)
| launch_contractor     = 
| last_contact          =
| disposal_type         = De-orbited
| decay_date            = {{plainlist|
*'''Proton 1''': {{end-date|11 October 1965|timezone=yes}}
*'''Proton 2''': {{end-date|6 February 1966|timezone=yes}}
*'''Proton 3''': {{end-date|16 September 1966|timezone=yes}}
*'''Proton 4''': {{end-date|24 July 1969|timezone=yes}}}}
| orbit_epoch           = 
| orbit_reference       = [[Geocentric orbit|Geocentric]]
| orbit_periapsis       = {{plainlist|
*'''Proton 1''': {{convert|183|km}} 
*'''Proton 2''': {{convert|189|km}} 
*'''Proton 3''': {{convert|185|km}} 
*'''Proton 4''': {{convert|248|km}}}} 
| orbit_apoapsis        = {{plainlist|
*'''Proton 1''': {{convert|589|km}}<ref name=nssdc1>{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1965-054A|title=Proton 1| publisher=NASA Space Science Data Coordinated Archive|access-date=23 October 2020}}</ref>
*'''Proton 2''': {{convert|608|km}}<ref name=nssdc2>{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1965-087A|title=Proton 2| publisher=NASA Space Science Data Coordinated Archive|access-date=23 October 2020}}</ref>
*'''Proton 3''': {{convert|585|km}}<ref name=nssdc3>{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1966-060A|title=Proton 3| publisher=NASA Space Science Data Coordinated Archive|access-date=23 October 2020}}</ref> 
*'''Proton 4''': {{convert|477|km}}}}<ref name=nssdc4>{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1968-103A|title=Proton 4| publisher=NASA Space Science Data Coordinated Archive|access-date=23 October 2020}}</ref>
| orbit_inclination     =  63.5° (1–3), 31.5° (4)
| orbit_period          =  ~92 minutes (1–4)
| orbit_eccentricity    =  .030 (1–3), .017 (4)
| apsis                 = gee

| programme             = 
| previous_mission      = 
| next_mission          = 
}}

{{Use dmy dates|date=January 2021}}
'''Proton''' ({{langx|ru|протон}}) ('[[proton]]') was a Soviet series of four cosmic ray and elementary particle detecting satellites. Orbited 1965–68, three on test flights of the [[UR-500]] [[ICBM]] and one on a [[Proton-K]] rocket, all four satellites completed their missions successfully, the last reentering the Earth's atmosphere in 1969.