Editing Apollo 15 (section)

{{Short description|Fourth crewed Moon landing}}{{pp-protected|small=yes}}
{{featured article}}
{{Use American English|date=January 2014}}
{{Use mdy dates|date=September 2013}}
{{Infobox spaceflight
| name = Apollo 15
| image = AS15-88-11866 - Apollo 15 flag, rover, LM, Irwin - restoration1.jpg
| image_caption = [[James Irwin]] salutes the [[Flag of the United States|United States flag]] on the Moon, August 2, 1971
| insignia = Apollo 15-insignia.png
| mission_type = Crewed lunar landing ([[List of Apollo missions#Alphabetical mission types|J]])
| operator = [[NASA]]<ref name="Orloff">{{cite book |last=Orloff |first=Richard W. |title=Apollo by the Numbers: A Statistical Reference |url=https://history.nasa.gov/SP-4029/SP-4029.htm |access-date=July 18, 2009 |series=NASA History Series |orig-year= 2000 |year=2004 |publisher=[[NASA]] |location=Washington, D.C. |isbn=978-0-16-050631-4 |chapter=Table of Contents |chapter-url=https://history.nasa.gov/SP-4029/Apollo_00g_Table_of_Contents.htm|archive-url=https://web.archive.org/web/20070823124845/https://history.nasa.gov/SP-4029/SP-4029.htm|archive-date=August 23, 2007}}</ref>
| COSPAR_ID = {{Unbulleted list
  |CSM: {{COSPAR|1971-063A}}<ref name="Apollo 15 CSM" />
  |LM: {{COSPAR|1971-063C}}<ref name="Apollo 15 LM">{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1971-063C|title=Apollo 15 Lunar Module /ALSEP|publisher=[[NASA Space Science Data Coordinated Archive]]|access-date=March 8, 2019}}</ref>
}}
| SATCAT = {{Unbulleted list
  |CSM: 5351<ref name="Apollo 15 CSM" />
  |LM: 5366<ref name = "Apollo 15 LM" />
}}
| mission_duration = 12&nbsp;days, 7&nbsp;hours, 11&nbsp;minutes, 53&nbsp;seconds{{sfn|Mission Report|p=3}}
| spacecraft = {{Unbulleted list
  |[[Apollo CSM]]-112<ref name="Apollo 15 CSM" />
  |[[Apollo Lunar Module|Apollo LM]]-10<ref name = "Apollo 15 LM" />
}}
| manufacturer = {{Unbulleted list
  |CSM: [[North American Rockwell]]<ref>{{cite web|title=Apollo 15 Command Module|url=https://airandspace.si.edu/collection-objects/command-module-apollo-15|publisher=[[Smithsonian Air and Space Museum]]|access-date=January 29, 2019|date=March 17, 2016|archive-date=July 22, 2019|archive-url=https://web.archive.org/web/20190722024924/https://airandspace.si.edu/collection-objects/command-module-apollo-15|url-status=dead}}</ref>
  |LM: [[Grumman]]<ref>{{cite web|title=Lunar Module LM-2|url=https://airandspace.si.edu/collection-objects/lunar-module-2-apollo|publisher=[[Smithsonian Air and Space Museum]]|access-date=March 7, 2019|date=March 21, 2016|archive-date=January 15, 2020|archive-url=https://web.archive.org/web/20200115082343/https://airandspace.si.edu/collection-objects/lunar-module-2-apollo|url-status=dead}}</ref>
}}
| launch_mass = {{cvt|107142|lb|kg|order=flip}}<ref name="Apollo 15 CSM" />
| landing_mass = {{cvt|11731|lb|kg|order=flip}}{{sfb|Mission Report|p=263}}
| launch_date = {{start date text|July 26, 1971, 13:34:00|timezone=yes}}&nbsp;UTC{{sfn|Mission Report|p=1}}
| launch_rocket = [[Saturn V]] SA-510{{sfn|Orloff & Harland|p=426}}
| launch_site = [[Kennedy Space Center|Kennedy]], [[Kennedy Space Center Launch Complex 39A|LC-39A]]<ref name="Apollo 15 CSM" />
| landing_date = {{end date text|August 7, 1971, 20:45:53|timezone=yes}}&nbsp;UTC{{sfn|Mission Report|p=3}}
| landing_site = North Pacific Ocean<br />{{coord|26|7|N|158|8|W|type:event|name=Apollo 15 splashdown}}{{sfn|Mission Report|p=3}}
| recovery_by = {{USS|Okinawa|LPH-3|6}}{{sfn|Mission Report|p=3}}
| orbit_epoch = July 30, 1971{{sfn|Mission Report|pp=10–11}}
| orbit_reference = [[selenocentric orbit|Selenocentric]]{{sfn|Mission Report|pp=10–11}}
| orbit_periapsis = {{convert|54.8|nmi|km|disp=out|abbr=on|1}} (54.8&nbsp;[[Nautical mile|nmi]]; {{convert|54.8|nmi|mi|disp=out|abbr=on|1}}){{sfn|Mission Report|pp=10–11}}
| orbit_apoapsis = {{convert|65.2|nmi|km|disp=out|abbr=on|1}} (65.2&nbsp;nmi; {{convert|65.2|nmi|mi|disp=out|abbr=on|1}}){{sfn|Mission Report|pp=10–11}}
| orbit_inclination = 23°{{sfn|Mission Report|pp=10–11}}
| orbit_period =
| apsis = selene
| interplanetary = {{Infobox spaceflight/IP
   |type                = orbiter
   |object              = [[Moon|Lunar]]
   |component           = [[Apollo command and service module|Command and service module]]
   |orbits              = 74<ref name = "15 background" />
   |arrival_date        = July 29, 1971, 20:05:46&nbsp;UTC<ref name = "15 timeline" />
   |departure_date      = August 4, 1971, 21:22:45&nbsp;UTC<ref name = "15 timeline" />
 }}
 {{Infobox spaceflight/IP
   |type                = lander
   |object              = [[Moon|Lunar]]
   |component           = [[Apollo Lunar Module|Lunar Module]]
   |arrival_date        = July 30, 1971, 22:16:29&nbsp;UTC<ref name="15 timeline">{{cite book|chapter-url=https://history.nasa.gov/SP-4029/Apollo_15i_Timeline.htm|access-date=January 29, 2019|year= 2005|last=Orloff |first=Richard W. |title=Apollo by the Numbers: A Statistical Reference |series=NASA History Series |orig-year= 2000 |publisher=[[NASA]] |location=Washington, D.C. |isbn=978-0-16-050631-4 |chapter=Apollo 15 timeline}}</ref>
   |departure_date      = August 2, 1971, 17:11:23&nbsp;UTC<ref name = "15 timeline" />
   |location            = [[Hadley–Apennine]]<br>
{{Coord|26.1322|N|3.6339|E|globe:Moon|display=inline}}<ref>{{cite web|url = 
https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1971-063C|title = NASA NSSDC Master Catalog – Apollo 15 LM descent stage|access-date = January 6, 2019|publisher = [[NASA Space Science Data Coordinated Archive]]|df = mdy-all}}</ref>
   |sample_mass         = {{cvt|77|kg|lb}}{{sfn|Mission Report|p=3}}
   |surface_EVAs        = 4 (including standup)
   |surface_EVA_time    = {{Unbulleted list
     |19&nbsp;hours, 7&nbsp;minutes, 53&nbsp;seconds<ref name = "15 timeline" />
     |<small>Standup: 33&nbsp;minutes, 7&nbsp;seconds</small><ref name = "15 timeline" />
     |<small>First: 6&nbsp;hours, 32&nbsp;minutes, 42&nbsp;seconds</small>{{sfn|Mission Report|p=15}}
     |<small>Second: 7&nbsp;hours, 12&nbsp;minutes, 14&nbsp;seconds</small>{{sfn|Mission Report|pp=15–16}}
     |<small>Third: 4&nbsp;hours, 49&nbsp;minutes, 50&nbsp;seconds</small>{{sfn|Mission Report|p=16}}
    }}
  }}
 {{Infobox spaceflight/IP
   |type                = rover
   |object              = [[Moon|Lunar]]
   |distance            = {{cvt|27.9|km|nmi mi|sp=us}}{{sfn|Mission Report|p=3}}
   |component           = <!-- LRV was not a spacecraft component -->
 }}
<!-- Cargo parameters -->| payload_items = {{Unbulleted list
  |Particles and Fields Subsatellite (PFS-1)
  |[[Lunar Roving Vehicle]]
}}
| cargo_mass = {{Unbulleted list
  |PFS-1: {{cvt|78.5|lb| kg|order=flip}}<ref name=presskit />
  |LRV: {{cvt|463|lb|kg|order=flip}}<ref name="15 background">{{cite book|chapter-url=https://history.nasa.gov/SP-4029/Apollo_15a_Summary.htm|access-date=January 29, 2019|year=2005|chapter=Apollo 15 The Ninth Mission: The Fourth Lunar Landing 26 July–7 August 1971|last=Orloff |first=Richard W. |title=Apollo by the Numbers: A Statistical Reference |series=NASA History Series |orig-year= 2000 |publisher=[[NASA]] |location=Washington, D.C. |isbn=978-0-16-050631-4 }}</ref>
}}
| instruments = <!-- a list of instruments on the satellite -->
| docking = {{Infobox spaceflight/Dock
   | docking_target     = LM
   | docking_type       = dock
   | docking_date       = July 26, 1971, 17:07:49&nbsp;UTC<ref name = "15 timeline" />
   | undocking_date     = July 30, 1971, 18:13:16&nbsp;UTC<ref name = "15 timeline" />
   | time_docked        =
 }}
 {{Infobox spaceflight/Dock
   | docking_target     = LM Ascent Stage
   | docking_type       = dock
   | docking_date       = August 2, 1971, 19:10:25&nbsp;UTC<ref name = "15 timeline" />
   | undocking_date     = August 3, 1971, 01:04:01&nbsp;UTC<ref name = "15 timeline" />
   | time_docked        =
 }}
| crew_size = 3
| crew_members = {{Unbulleted list
  |[[David Scott|David R. Scott]]
  |[[Alfred Worden|Alfred M. Worden]]
  |[[James Irwin|James B. Irwin]]
}}
| crew_EVAs = 1 in [[wikt:cislunar|cislunar]] space and 4 on the lunar surface<ref name = "15 timeline" />
| crew_EVA_duration = 39&nbsp;minutes, 7&nbsp;seconds<ref name = "15 timeline" /><br /><small>Spacewalk to retrieve film cassettes</small>
| crew_callsign = {{Unbulleted list
  |CSM: ''Endeavour''
  |LM: ''Falcon''
}}
| crew_photo = The Apollo 15 Prime Crew - GPN-2000-001169.jpg
| crew_photo_caption = Left to right: [[David Scott|Scott]], [[Alfred Worden|Worden]], [[James Irwin|Irwin]]
| crew_photo_alt = Apollo 15 crew
| previous_mission = [[Apollo 14]]
| next_mission = [[Apollo 16]]
| programme = [[Apollo program]]
}}
{{Apollo15series}}

'''Apollo 15''' (July 26{{snd}}August 7, 1971) was the ninth crewed mission in the [[Apollo program]] and the fourth [[Moon landing]]. It was the first [[List of Apollo missions#Alphabetical mission types|J&nbsp;mission]], with a longer stay on the [[Moon]] and a greater focus on science than earlier landings. Apollo 15 saw the first use of the [[Lunar Roving Vehicle]].

The mission began on July 26 and ended on August 7, with the lunar surface exploration taking place between July 30 and August 2. [[Apollo Commander|Commander]] [[David Scott]] and [[Lunar Module Pilot]] [[James Irwin]] landed near [[Hadley–Apennine#Rima Hadley|Hadley Rille]] and explored the local area using the rover, allowing them to travel further from the [[Apollo Lunar Module|Lunar Module]] than had been possible on previous missions. They spent 18{{frac|1|2}} hours on the Moon's surface on four [[extravehicular activities]] (EVA), and collected {{convert|77|kg|order=flip}} of surface material.

At the same time, [[Command Module Pilot]] [[Alfred Worden]] orbited the Moon, operating the sensors in the [[scientific instrument module]] (SIM) bay of the [[Apollo service module|service module]]. This suite of instruments collected data on the Moon and its environment using a panoramic camera, a [[gamma-ray spectrometer]], a mapping camera, a laser [[altimeter]], a [[Mass spectrometry|mass spectrometer]], and a lunar subsatellite deployed at the end of the moonwalks. The Lunar Module returned safely to the command module and, at the end of Apollo 15's 74th [[lunar orbit]],<ref>{{Cite web|url=https://history.nasa.gov/SP-4029/Apollo_15a_Summary.htm|title=APOLLO 15|website=history.nasa.gov}}</ref> the engine was fired for the journey home. During the return trip, Worden performed the first [[spacewalk]] in deep space. The Apollo 15 mission splashed down safely on August{{nbsp}}7 despite the partial opening of one of its three parachutes.

The mission accomplished its goals and also saw the collection of the [[Genesis Rock]], thought to be part of the Moon's early [[crust (geology)|crust]], and Scott's use of a hammer and a feather to validate [[Galileo's Leaning Tower of Pisa experiment|Galileo's theory]] that when there is no air resistance, objects fall at the same rate due to gravity regardless of their mass. The mission received negative publicity the following year when it emerged that [[Apollo 15 postal covers incident|the crew had carried unauthorized postal covers]] to the lunar surface, some of which were sold by a [[West German]] stamp dealer. The members of the crew were reprimanded for poor judgment, and did not fly in space again.