[[File:B01Magellanic Clouds.jpg|right|250px|thumb|The Large and Small Magellanic Clouds (the LMC and SMC, respectively). Image taken by the European Southern Observatory[http://www.eso.org/public/]]]
The '''Magellanic Clouds''' are two nearby irregular [[galaxy|dwarf galaxies]] that are visible in the southern night sky, which are part of our [[Local Group]] of galaxies. They are referred to individually as the '''Large Magellanic Cloud''' (LMC) and the '''Small Magellanic Cloud''' (SMC). Traditionally thought to be satellite galaxies, gravitationally bound to the [[Milky Way]], more recent observations have challenged that long held notion.
As the Magellanic Clouds appear as visible, misty patches in the night sky to the unaided eye, they have been known since the dawn of history to the people of the Southern hemisphere and even as far north as 12<sup>o</sup> Northern latitude. The people of [[Polynesia]] referred to the galaxies as ''Mahu''. The first known recorded mention of the two galaxies is by [[Persian]] [[astronomer]] [[Al Sufi]] in 964 in his record known as the ''Book of Fixed Stars'', naming them ''al-Bakr'', or "the White Ox".<ref name="lore">http://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Nubeculae_Magellani*.html</ref>
The two galaxies were unknown to [[Europeans]] until the end of the 15th century when they were observed by '''Peter Martyr d'Anghiera''' and '''Andreas Corsali''' and later recorded in the former's writings, collectively known as ''Decades''. [[Amerigo Vespucci]] also made mention of the clouds during his third voyage in 1503-4.<ref>http://messier.obspm.fr/xtra/Bios/vespucci.html</ref> Later, during the circumnavigation voyage of [[Ferdinand Magellan]] (1519-221519–22), they were observed and recorded by the [[Venetian]] [[scholar]] '''Antonio Pigafetta''', who traveled along. The name "Magellanic Clouds" though did not become associated with the galaxies until much later. In [[Italian]], the Large and Small cloud are called ''Nube Maggiore'' and ''Nube Minore'' respectively. In [[French]] they are ''Grand Nuage'' and ''Petit Nuage'', and in [[German]], they are called ''Grosse Wolke'' and ''Kleine Wolke''.<ref name="lore">http://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Nubeculae_Magellani*.html</ref>
==Characteristics==
The two Magellanic Clouds were believed to be the closest galaxies to our own until 1994, when the '''Sagittarius Dwarf Elliptical''' galaxy was discovered. The two galaxies themselves appear 21<sup>o</sup> apart in the night sky.
In 2007, a team of astronomers from the Harvard-Smithsonian Center for Astrophysics, using input from the [[Hubble Telescope]] accurately measured both the radial and proper velocity of the Magellanic Clouds, which clocked their passage through the region of our galaxy at over 480 km/s. Due to this high relative velocity, it is now believed that the two galaxies are not gravitationally bound satellites of the [[Milky Way]], as once believed, thus requiring a revision of many of the previously assumed effects they have on the Milky Way.<ref>http://arxiv.org/abs/astro-ph/0703196</ref><ref>http://www.cfa.harvard.edu/news/2007/pr200722.html</ref>
===Large Magellanic Cloud===
The '''Large Magellanic Cloud''' (LMC) was thought to be the closest galaxy to the Milky Way, (the '''Sagittarius Dwarf Elliptical''' and '''Canis Major Dwarf''' are now known to be closer). From our vantage point on Earth, the galaxy has an apparent magnitude of 0.1 and sits across the [[constellation|constellations]] s of [[Dorado]] and [[Mensa_Mensa (constellation)|Mensa]], spanning 8<sup>o</sup> of the night sky.<ref>http://www.britannica.com/EBchecked/topic/356551/Magellanic-Cloud</ref>
The galaxy itself is an irregular dwarf. It holds about one-tenth of the mass of our own Milky Way. A central bar of stars show prominently in its structure, as well as a single spiral arm. The galaxy is considered a treasure trove of celestial phenomena to astronomers, with 60 [[globular cluster|globular clusters]]s, 400 [[planetary nebula]], and 700 [[open cluster|open clusters]] s identified thus far, along with hundreds of thousands of stars including many [[supergiant|supergiants]]s.<ref>Burnham, Robert, Jr. (1978). Burnham's Celestial Handbook: Volume Two. New York: Dover. p. 840-47. ISBN 048623567X.</ref>
Two of the most notable features of the Large Magellanic Cloud are the '''Tarantula Nebula''' and the supernova remnant known as '''Lionel-Murphy SNR'''. The Tarantula Nebula is the known as the most active region of star formation in the Local Group of galaxies as well as one of the largest nebulae known. Lionel-Murphy SNR is the remains of Supernova 1987a, which occurred in 1987 and was the closest observed [[supernova]] to Earth since 1604.