Editing 1840s (section)

==== Antarctica ====
* [[January 19]], [[1840]] – Captain [[Charles Wilkes]]' [[United States Exploring Expedition]] sights what becomes known as [[Wilkes Land]] in the southeast quadrant of [[Antarctica]], claiming it for the [[United States]] and providing evidence that Antarctica is a complete continent.<ref>{{cite web|url=http://www.quarkexpeditions.com/antarctica/exploration.shtml|title=Antarctic Exploration — Chronology|access-date=2006-10-20|publisher=Quark Expeditions|year=2004|archive-url=https://web.archive.org/web/20060908120017/http://www.quarkexpeditions.com/antarctica/exploration.shtml |archive-date=2006-09-08}}</ref>
* [[January 21]], [[1840]] – [[Dumont D'Urville]] discovers [[Adélie Land]] in [[Antarctica]], claiming it for [[France]].<ref>{{cite book|last=Guillon|first=Jacques|title=Dumont d'Urville|publisher=France-Empire|year=1986|location=Paris|isbn=978-2-7048-0472-6}}</ref>
* [[January 27]], [[1841]] – The active [[volcano]] [[Mount Erebus]] in [[Antarctica]] is discovered and named by [[James Clark Ross]].<ref>Ross, ''Voyage to the Southern Seas'', '''1''', pp. 216–8.</ref>
* [[January 28]], [[1841]] – Ross discovers the "Victoria Barrier", later known as the [[Ross Ice Shelf]]. On the same voyage, he discovers the [[Ross Sea]], [[Victoria Land]] and [[Mount Terror (Antarctica)|Mount Terror]].
* [[January 23]], [[1842]] – [[Antarctic]] explorer [[James Clark Ross]], charting the eastern side of [[James Ross Island]], reaches a [[Farthest South]] of 78°09'30"S.<ref>{{cite book|last=Coleman|first=E. C.|title=The Royal Navy in Polar Exploration, from Frobisher to Ross|publisher=Tempus Publishing|location=Stroud|year=2006|isbn=978-0-7524-3660-9|page=335}}</ref>
* [[January 6]], [[1843]] – [[Antarctic]] explorer [[James Clark Ross]] discovers [[Snow Hill Island]].