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→Characteristics
==Characteristics==
==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, with their actual distance from each other is some 75,000 light years.
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>
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===
===Large Magellanic Cloud===
The '''Large Magellanic Cloud''' (LMC) is located some 160,000 light years and once 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]] of [[Dorado]] and [[Mensa_(constellation)|Mensa]], spanning 8<sup>o</sup> of the night sky.<ref>http://www.britannica.com/EBchecked/topic/356551/Magellanic-Cloud</ref>
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]] of [[Dorado]] and [[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 a 14,000 light year in diameter 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]], 400 [[planetary nebula]], and 700 [[open cluster|open clusters]] identified thus far, along with hundreds of thousands of stars including many [[supergiant|supergiants]].<ref>Burnham, Robert, Jr. (1978). Burnham's Celestial Handbook: Volume Two. New York: Dover. p. 840-47. ISBN 048623567X.</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]], 400 [[planetary nebula]], and 700 [[open cluster|open clusters]] identified thus far, along with hundreds of thousands of stars including many [[supergiant|supergiants]].<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.
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.
===Small Magellanic Cloud===
===Small Magellanic Cloud===
The '''Small Magellanic Cloud''' is located some 200,000 light years away and is the fourth closest galaxy to our own. In the night sky, it is located in the constellation of [[Tucana]], spanning 3<sup>o</sup> across in the night sky, lying some 20 degrees to the east of the Large Magellanic Cloud.
The '''Small Magellanic Cloud''' is the fourth closest galaxy to our own. In the night sky, it is located in the constellation of [[Tucana]], spanning 3<sup>o</sup> across in the night sky, lying some 20 degrees to the east of the Large Magellanic Cloud.
The galaxy itself may perhaps have once a barred spiral galaxy much like our own, before being disrupted by the Milky Way.<ref>http://coolcosmos.ipac.caltech.edu//cosmic_classroom/multiwavelength_astronomy/multiwavelength_museum/smc.html</ref> Its diameter is 7,000 light years across, and contains hundreds of million of stars with a total mass of one-fifteenth of that of the [[Milky Way]].
The galaxy itself may perhaps have once a barred spiral galaxy much like our own, before being disrupted by the Milky Way.<ref>http://coolcosmos.ipac.caltech.edu//cosmic_classroom/multiwavelength_astronomy/multiwavelength_museum/smc.html</ref> Its diameter is 7,000 light years across, and contains hundreds of million of stars with a total mass of one-fifteenth of that of the [[Milky Way]].