Changes

}}

}}

The '''Orion Nebula''' (also known as '''Messier 42'''), is the brightest star forming, diffuse nebula in the sky, situated south of the belt of [[Orion]].  Having an apparent magnitude of +3, the nebula can be seen by the unaided eye in moderately dark skies. It is estimated to be some 24 light years across and is some 1,344±20 light years from Earth<ref>http://arxiv.org/abs/0902.3913</ref>. The Orion Nebula itself is only part of a vastly larger star forming nebular region called the '''Orion Molecular Cloud Complex'''.

The '''Orion Nebula''' (also known as '''Messier 42'''), is the brightest star forming, diffuse nebula in the sky, situated south of the belt of [[Orion]].  Having an apparent magnitude of +3, the nebula can be seen by the unaided eye in moderately dark skies. It is estimated to be some 24 light years across and is some 1,344±20 light years from Earth.<ref>http://arxiv.org/abs/0902.3913</ref>  The Orion Nebula itself is only part of a vastly larger star forming nebular region called the '''Orion Molecular Cloud Complex'''.

==History==

==History==

The nebula was probably known to ancient people as it is visible to the naked eye, the Maya had a folk tale which dealt with the region of the sky with Orion.<ref>Krupp, Edward C. “Igniting the Hearth.” Sky & Telescope (February 1999): 94.</ref> [[Ptolemy]] did include it in the ''Almagest'' (Great Book), [[Tycho Brahe]] also made note of the object in the late 16th century, and in 1603, [[Johann Bayer]] recorded it as '''Theta Orion''' in his ''Uranometria''. [[Galileo]] also looked towards the region the nebular is located and and detected several faint stars.  None of these astronomers though, realized there was a nebula.

The nebula was probably known to ancient people as it is visible to the naked eye, the Maya had a folk tale which dealt with the region of the sky with Orion.<ref>Krupp, Edward C. “Igniting the Hearth.” Sky & Telescope (February 1999): 94.</ref> [[Ptolemy]] did include it in the ''Almagest'' (Great Book), [[Tycho Brahe]] also made note of the object in the late 16th century, and in 1603, [[Johann Bayer]] recorded it as '''Theta Orion''' in his ''Uranometria''. [[Galileo]] also looked towards the region the nebular is located and and detected several faint stars.  None of these astronomers though, realized there was a nebula.

The credit for discovering the nebula is given to '''Nicholas-Claude Fabri de Peiresc''' who in 1610 first recorded of a cloudy nebulosity in the [[Orion]] constellation.  [[Jesuit]] astronomer '''Johann Baptist Cysatus''' independently found the nebula in 1611 and published a note about it seven years later<ref name="history">http://messier.obspm.fr/Mdes/dm042.html</ref>. It was independently rediscovered by [[Christiaan Huygens]] in 1656, who is often credited for its discovery.  The designation M42 was given to the nebula by [[Charles Messier]], who recorded it in the first edition of his catalog of deep sky objects in 1774 (completed in 1771)<ref name="history">http://messier.obspm.fr/Mdes/dm042.html</ref>. The nebula is also known as the first deep sky observation by [[William Herschel]] in 1774, using the new reflecting telescope he'd recently completed<ref name="history">http://messier.obspm.fr/Mdes/dm042.html</ref>.

The credit for discovering the nebula is given to '''Nicholas-Claude Fabri de Peiresc''' who in 1610 first recorded of a cloudy nebulosity in the [[Orion]] constellation.  [[Jesuit]] astronomer '''Johann Baptist Cysatus''' independently found the nebula in 1611 and published a note about it seven years later.<ref name="history">http://messier.obspm.fr/Mdes/dm042.html</ref>  It was independently rediscovered by [[Christiaan Huygens]] in 1656, who is often credited for its discovery.  The designation M42 was given to the nebula by [[Charles Messier]], who recorded it in the first edition of his catalog of deep sky objects in 1774 (completed in 1771).<ref name="history"/>  The nebula is also known as the first deep sky observation by [[William Herschel]] in 1774, using the new reflecting telescope he'd recently completed.<ref name="history"/>

Using [[spectroscopy]], the gaseous nature of the Orion Nebula was identified in 1865 by [[William Huggins]]. On September 30, 1880, the Orion Nebula became the first nebula to be successfully photographed, by Henry Draper, who later obtained a second, more detailed photograph of the Orion Nebula.  In 1993, the [[Hubble Space Telescope]] first looked to the Orion Nebula, and in 2005 recorded the most detailed images of the nebula yet, photographing over 3,000 stars contained within.<ref>http://adsabs.harvard.edu/abs/2005AAS...20714601R</ref>

Using [[spectroscopy]], the gaseous nature of the Orion Nebula was identified in 1865 by [[William Huggins]]. On September 30, 1880, the Orion Nebula became the first nebula to be successfully photographed, by Henry Draper, who later obtained a second, more detailed photograph of the Orion Nebula.  In 1993, the [[Hubble Space Telescope]] first looked to the Orion Nebula, and in 2005 recorded the most detailed images of the nebula yet, photographing over 3,000 stars contained within.<ref>http://adsabs.harvard.edu/abs/2005AAS...20714601R</ref>

The Trapezium Cluster itself, first observed by Galileo as a group of stars, is an [[open cluster]] of eight known newborn stars, several of which are [[binary star|binaries]].  The cluster was created right out of the nebula and each of the stars are within 1.5 light years of each other.  It may be part of the larger '''Orion Nebula Cluster''', which contain some 2,000 stars in total, spread over an area of 20 light years.

The Trapezium Cluster itself, first observed by Galileo as a group of stars, is an [[open cluster]] of eight known newborn stars, several of which are [[binary star|binaries]].  The cluster was created right out of the nebula and each of the stars are within 1.5 light years of each other.  It may be part of the larger '''Orion Nebula Cluster''', which contain some 2,000 stars in total, spread over an area of 20 light years.

The Orion Nebula is the primary example of a stellar nursery where new stars are being born. Recent observations of the nebula have revealed approximately 700 stars in various stages of formation within the nebula.  In addition, the Hubble has found over 150 proplys, ([[protoplanetary disk|protoplanetary disks]]) in the nebula<ref>http://adsabs.harvard.edu/abs/1996AJ....111.1977M</ref>. Such systems are considered to be the earliest stages of solar system formation.  The large number located just in this one nebula is viewed as evidence that the formation of star systems is a common occurrence in the universe.

The Orion Nebula is the primary example of a stellar nursery where new stars are being born. Recent observations of the nebula have revealed approximately 700 stars in various stages of formation within the nebula.  In addition, the Hubble has found over 150 proplys, ([[protoplanetary disk]]s) in the nebula.<ref>http://adsabs.harvard.edu/abs/1996AJ....111.1977M</ref>  Such systems are considered to be the earliest stages of solar system formation.  The large number located just in this one nebula is viewed as evidence that the formation of star systems is a common occurrence in the universe.

    

    

{{reflist}}

{{reflist}}

==External Links==

==External links==

*[http://chandra.harvard.edu/photo/2007/orion/ Orion Nebula observed by Chandra]

*[http://chandra.harvard.edu/photo/2007/orion/ Orion Nebula observed by Chandra]

*[http://messier.obspm.fr/more/m042-043_more.html Additional Images of the Orion Nebula]

*[http://messier.obspm.fr/more/m042-043_more.html Additional Images of the Orion Nebula]

*[http://www.spacetelescope.org/news/html/heic0601.html  Images of Orion by the ESA and Hubble]

*[http://www.spacetelescope.org/news/html/heic0601.html  Images of Orion by the ESA and Hubble]