View source for Lunar Orbiter 3

{{Short description|NASA orbiter mission to the Moon (1967)}}
{{Use American English|date=January 2014}}
{{Use mdy dates|date=May 2020}}
{{Infobox spaceflight
| name                  = Lunar Orbiter 3
| image                 = Lunar Orbiter 3 moon image.jpg
| image_caption         = ''Lunar Orbiter 3'' image of the far side of the Moon, enhanced by [[LOIRP]]
| image_size            = 300px

| mission_type          = [[Moon|Lunar]] orbiter
| operator              = [[NASA]]
| COSPAR_ID             = 1967-008A 
| SATCAT                = 2666
| website               = [https://science.nasa.gov/mission/lunar-orbiters-program/ science.nasa.gov]
| mission_duration      = {{time interval|5 Feb 1967|9 Oct 1967|sep=,}}
 
| manufacturer          = [[Langley Research Center]]
| launch_mass           = {{cvt|385.6|kg|lb}}<ref name=Siddiqi_2018/>
| dimensions            = {{cvt|3.72|xx|1.65|xx|1.5|m|ft}}<ref name=nssdc1/>
| power                 = 375 watts<ref name=nssdc1/>

| launch_date           = {{start-date|February 5, 1967, 01:17:01|timezone=yes}}&nbsp;UTC<ref name=Siddiqi_2018/> 
| launch_rocket         = [[Atlas-Agena|Atlas SLV-3 Agena-D]]  
| launch_site           = [[Cape Canaveral Air Force Station|Cape Canaveral]] [[Cape Canaveral Air Force Station Launch Complex 13|LC-13]]

| disposal_type         = Deorbited
| decay_date            = {{end-date|October 9, 1967, 10:27:11}}&nbsp;UTC<ref name=nssdc1/>

| orbit_epoch           = February 7, 1967, 19:00:00&nbsp;UTC<ref name=nssdc1/>
| orbit_reference       = [[selenocentric orbit|Selenocentric]]
| orbit_periapsis       = {{cvt|1791|km|mi}}
| orbit_apoapsis        = {{cvt|3598|km|mi}} 
| orbit_inclination     = 20.9&nbsp;degrees
| orbit_period          = 208.1&nbsp;minutes
| orbit_semimajor       = {{cvt|2694|km|mi}}
| orbit_eccentricity    = 0.33
| apsis                 = selene

|interplanetary         = 
 {{Infobox spaceflight/IP
   |type                = orbiter
   |object              = [[Moon|Lunar]]
   |orbits              = 1,702
   |arrival_date        = February 8, 1967, 21:54&nbsp;UTC
   |location            = {{Lunar coords and quad cat|14.3|N|97.7|W}}
 }}

| trans_frequency       = 2295 [[Hertz|MHz]]<ref name=nssdc1/>

| instruments_list       = <!-- start collapsible list of instruments -->
{{Infobox spaceflight/Instruments
  |acronym1  = - | name1  = Cesium Iodide Dosimeters<ref name=nssdc2/>
  |acronym2  = - | name2  = Lunar Photographic Studies<ref name=nssdc3/>
  |acronym3  = - | name3  = Meteoroid Detectors<ref name=nssdc4/>
  |acronym4  = - | name4  = Selenodesy<ref name=nssdc5/>
}}

| programme             = '''[[Lunar Orbiter program|''Lunar Orbiter'' program]]'''
| previous_mission      = [[Lunar Orbiter 2]]
| next_mission          = [[Lunar Orbiter 4]]
}}

The '''Lunar Orbiter 3''' was a [[spacecraft]] launched by [[NASA]] in 1967 as part of the [[Lunar Orbiter program|Lunar Orbiter Program]].<ref name=Byers_1976/> It was designed primarily to photograph areas of the [[Moon|lunar]] surface for confirmation of safe landing sites for the [[Surveyor program|Surveyor]] and [[Apollo program|Apollo]] missions. It was also equipped to collect selenodetic, [[radiation]] intensity, and [[micrometeoroid]] impact data.

==Mission summary==
[[File:NASM-A19700318000-NASM2018-00097.jpg|thumb|left|Replica of a ''Lunar Orbiter'' spacecraft]]

The spacecraft was placed in a cislunar trajectory and injected into an elliptical near-equatorial lunar orbit on February 8 at 21:54 UT. The orbit was {{convert|210.2|x|1801.9|km}} with an inclination of 20.9 degrees and a period of 3 hours 25 minutes. After four days (25 orbits) of tracking the orbit was changed to {{convert|55|x|1847|km}}. The spacecraft acquired photographic data from February 15 to 23, 1967, and readout occurred through March 2, 1967. The film advance mechanism showed erratic behavior during this period resulting in a decision to begin readout of the frames earlier than planned. The frames were read out successfully until March 4 when the film advance motor burned out, leaving about 25% of the frames on the takeup reel, unable to be read.<ref name=nasa2/>

[[File:Lunar Orbiter 3 coverage.jpg|thumb|left|Spacecraft orbit and photographic coverage on the near side (left) and far side (right)]]

A total of 149 medium resolution and 477 high resolution frames were returned.<ref name=lpi3/> The frames were of excellent quality with resolution down to {{convert|1|m}}. Included was a frame of the [[Surveyor 1]] landing site, permitting identification of the location of the spacecraft on the surface.  The future landing site of [[Apollo 14]] including [[Cone (crater)|Cone]] crater, was photographed by the orbiter.<ref name=nasa1/> Accurate data were acquired from all other experiments throughout the mission.<ref name=Hansen_1970/> The spacecraft was used for tracking purposes until it struck the lunar surface on command at 14.3 degrees N latitude, 97.7 degrees W longitude ([[selenographic coordinates]]) on October 9, 1967.

{|class="wikitable"
|+Instruments
|-
|'''Lunar Photographic Studies'''|| Evaluation of Apollo and Surveyor landing sites
|-
|'''Meteoroid Detectors'''|| Detection of micrometeoroids in the lunar environment
|-
|'''Caesium Iodide Dosimeters'''|| Radiation environment en route to and near the Moon
|-
|'''Selenodesy'''|| Gravitational field and physical properties of the Moon
|}

<gallery widths="200px" heights="180px">
Image:Apollo Project - Liftoff of Lunar Orbiter III.jpg|Launch of ''Lunar Orbiter 3'' from an [[Atlas-Agena]] rocket on February 5, 1967
Image:Lunar Orbiter 3 - FRAME 3040-H2 - DPLA - ef9f3cec4c2a25df602c8e80cbf18ead.jpg|Unnamed rille southwest of [[Manners (crater)|Manners]] crater in Mare Tranquillitatis, on February 16, 1967 ({{coord|3.57|N|19.49|E|globe:moon_type:landmark}})
Image:Lunar Orbiter 3 - FRAME 3103-M - DPLA - f2e1ce1c997d7a3b64a53e416f201418.jpg|[[Schröter (lunar crater)|Rima Schröter]], on February 18, 1967 ({{coord|0.93|N|6.21|W|globe:moon_type:landmark}})
Image:Lunar Orbiter 3 - FRAME 3110-H2 - DPLA - 330fa729d3faf46688eb64450c3f0c3c.jpg|View inside [[Hipparchus (lunar crater)|Hipparchus]] crater on February 19, 1967 ({{coord|4.77|S|4.28|E|globe:moon_type:landmark}})
Image:Surveyor 1 on lunar surface photographed by Lunar Orbiter III.tif|[[Kepler (lunar crater)|Kepler]] crater on April 28, 1967
Image:Intricate young ejecta blanket in ancient Murchison Crater (LROC25).jpg|Oblique view of [[Murchison (crater)|Murchison]] crater
</gallery>

==See also==
{{Portal|Spaceflight}}{{Commons category|}}
* [[Lunar Orbiter Image Recovery Project]]
* [[Exploration of the Moon]]
* [[List of artificial objects on the Moon]]
* [[List of missions to the Moon]]
** [[Lunar Orbiter 1]]
** [[Lunar Orbiter 2]]
** [[Lunar Orbiter 4]]
** [[Lunar Orbiter 5]]

==References==
{{Reflist|refs=

<ref name="Byers_1976">{{cite book
| author1= B. A. Byers
| title= Destination Moon: A History of the Lunar Orbiter Program
| url= https://ntrs.nasa.gov/citations/19770016195
| publisher= [[NASA]]
| date= 1976
| access-date= 12 November 2022
| isbn= 978-1-495-92029-5
| id= NASA-TM-X-3487 }}
</ref>

<ref name="Hansen_1970">{{cite book
| author1= Thomas P. Hansen
| title= Guide to Lunar Orbiter Photographs
| url= https://ntrs.nasa.gov/citations/19710026703
| publisher= [[NASA]]
| date= 1970
| access-date= 13 November 2022
| isbn= 978-1-499-16108-3
| id= NASA-SP-242 }}
</ref>

<ref name="lpi3">{{cite web
| url= http://www.lpi.usra.edu/resources/lunarorbiter/mission/?3
| title= Lunar Orbiter Photo Gallery - Mission 3
| publisher= [[Lunar and Planetary Institute]]
| access-date= 13 November 2022 }}
</ref>

<ref name="nasa1">{{cite book
| title= Apollo 14 Preliminary Science Report
| url= https://ntrs.nasa.gov/citations/19710021477
| publisher= [[NASA]]
| date= 1971
| id= NASA-SP-272
| isbn= 978-1-502-72648-3 }}
</ref>

<ref name="nasa2">{{cite web
| title= Lunar Orbiter 3
| url= https://science.nasa.gov/mission/lunar-orbiter-3/
| website= science.nasa.gov
| date= December 8, 2017
| publisher= [[NASA]]
| access-date= 19 August 2024 }}
</ref>

<ref name="nssdc1">{{cite web
| title= Lunar Orbiter 3
| url= https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1967-008A
| website= nssdc.gsfc.nasa.gov
| publisher= [[NASA]]
| access-date= 2 May 2018 }}
</ref>

<ref name="nssdc2">{{cite web
| title= Lunar Orbiter 3: Cesium Iodide Dosimeters
| url= https://nssdc.gsfc.nasa.gov/nmc/experiment/display.action?id=1967-008A-04
| website= nssdc.gsfc.nasa.gov
| publisher= [[NASA]]
| access-date= 19 August 2024 }}
</ref>

<ref name="nssdc3">{{cite web
| title= Lunar Orbiter 3: Lunar Photographic Studies
| url= https://nssdc.gsfc.nasa.gov/nmc/experiment/display.action?id=1967-008A-01
| website= nssdc.gsfc.nasa.gov
| publisher= [[NASA]]
| access-date= 19 August 2024 }}
</ref>

<ref name="nssdc4">{{cite web
| title= Lunar Orbiter 3: Meteoroid Detectors
| url= https://nssdc.gsfc.nasa.gov/nmc/experiment/display.action?id=1967-008A-03
| website= nssdc.gsfc.nasa.gov
| publisher= [[NASA]]
| access-date= 19 August 2024 }}
</ref>

<ref name="nssdc5">{{cite web
| title= Lunar Orbiter 3: Selenodesy
| url= https://nssdc.gsfc.nasa.gov/nmc/experiment/display.action?id=1967-008A-02
| website= nssdc.gsfc.nasa.gov
| publisher= [[NASA]]
| access-date= 19 August 2024 }}
</ref>

<ref name="Siddiqi_2018">{{ cite book
| author1= Asif Siddiqi
| 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
| publisher= [[NASA]]
| edition= second
| year= 2018
| isbn= 978-1-626-83043-1 }}
</ref>

}}

{{Lunar Orbiter program}}
{{Moon spacecraft}}
{{Orbital launches in 1967}}
{{NASA space program}}

[[Category:Lunar Orbiter program|3]]
[[Category:Spacecraft launched in 1967]]
[[Category:Spacecraft that orbited the Moon]]
[[Category:Spacecraft that impacted the Moon]]
[[Category:1967 on the Moon]]