Editing Tranquility Base (section)

==Name==
[[File:AP11 FINAL APPROACH.ogv|thumb|Armstrong pilots the [[Lunar Module Eagle|Apollo Lunar Module ''Eagle'']] and lands on the Moon, July 20, 1969, creating Tranquility Base]]
Armstrong named the site at 20:17:58 [[Universal Coordinated Time|UTC]], approximately 18 seconds after his and Aldrin's successful landing, as he announced:
<blockquote>[[Christopher C. Kraft Jr. Mission Control Center|Houston]], Tranquility Base here. The ''[[Lunar Module Eagle|Eagle]]'' has landed.<ref>{{cite web|url=http://www.hq.nasa.gov/alsj/a11/a11.landing.html|title=Apollo 11 Lunar Surface Journal: The First Lunar Landing|last=Jones|first=Eric M.|publisher=Apollo Lunar Surface Journal|via=NASA|date=1995|access-date=2009-07-15|archive-date=2016-12-27|archive-url=https://web.archive.org/web/20161227230604/http://www.hq.nasa.gov/alsj/a11/a11.landing.html|url-status=dead}}</ref>
</blockquote>

During training, Armstrong and Aldrin had exclusively used the callsign "Eagle" in simulated ground conversations, both before and after landing.<ref name="failure">''Failure is Not an Option''. [[History (U.S. TV channel)|History]], 24 August 2003.</ref> Armstrong and Aldrin decided on using "Tranquility Base" just before the flight, telling only [[Capsule communicator|Capsule Communicator]] [[Charles Duke]] before the mission, so Duke would not be taken by surprise.<ref name="chaikin_206">{{Cite book |author=Chaikin, Andrew |title=A Man on the Moon: The Triumphant Story Of The Apollo Space Program |date=2007|publisher=[[Penguin Group]] |location=New York |page=637|isbn=978-0-14-311235-8}} Author's note on page 206.</ref>

The name has become a permanent designation for the site. Although the name was designated by the Apollo astronauts, the [[International Astronomical Union]] officially recognizes the designation "Tranquility Base". It is listed on lunar maps as ''Statio Tranquillitatis'', conforming to the standard use of [[Latin]] for lunar place names.