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The '''Crab Nebula''', also know as '''M1''' and '''NGC 1952''', is a supernova remnant surrounding a [[neutron star]]. The most famous [[nebula]], it is the result of a [[supernova]] event that was first observed on [[Earth]] in 1054 A.D.  The nebula is located around 6,500 light years away in the constellation of [[Taurus]].  At present the expanding nebular is some 11 light years across and growing at a rate of 1500 km/s.

The '''Crab Nebula''', also know as '''M1''' and '''NGC 1952''', is an expanding gas cloud surrounding a [[neutron star]] located in the constellation of [[Taurus]] near the star [[Zeta Tauri]], the south horn of the bull. Possibly the most famous [[nebula]], it is the result of a [[supernova]] event that was first observed on [[Earth]] in 1054 A.D.  Since then, the nebula has been expanding at a rate of 1500 km/s and is now on average some 11 light years in diameter.

==Supernova Event==

==Supernova Event==

The Crab Nebula is the result of the supernova event called '''SN1054'''.  This event was first recorded by [[Chinese]] and [[Arab]] astronomers on July 4th, 1054 A.D. as a "guest star".  The event was possibly also the inspiration for art created by [[Anasazi]] [[Indians]].<ref>http://www.astronomy.pomona.edu/archeo/outside/chaco/nebula.html</ref> Initially the supernova had an apparent magnitude of -6, making it brighter then even [[Venus]].  The star then began to fade, but remained subsequently bright enough to be observed during the day for the next 23 days, and at night for the next 653 days before fading from view.<ref>http://www.seds.org/messier/more/m001_sn.html</ref> The supernova has been classified since with the variable star designation '''CM Tauri'''.  

The Crab Nebula is the result of the supernova event called '''SN1054''', which was first recorded by [[Chinese]] and [[Arab]] astronomers on July 4th, 1054 A.D. as a "guest star".  The event was possibly also the inspiration for astronomy related art created by [[Anasazi]] [[Indians]].<ref>http://www.astronomy.pomona.edu/archeo/outside/chaco/nebula.html</ref> Initially the supernova had an apparent magnitude of -6, making it brighter then even [[Venus]].  The star then began to fade, but remained subsequently bright enough to be observed during the day for the next 23 days, and at night for the next 653 days before finally fading from view.<ref>http://www.seds.org/messier/more/m001_sn.html</ref> The supernova has been classified since with the variable star designation '''CM Tauri'''.  

The progenitor star for the explosion is calculated to be between 9 and 11 solar masses, this is based on theoretical models of supernova explosions.<ref>http://adsabs.harvard.edu/abs/1985cnrs.work...97N</ref>

The progenitor star for the explosion is calculated to be between 9 and 11 solar masses, this is based on theoretical models of supernova explosions.<ref>http://adsabs.harvard.edu/abs/1985cnrs.work...97N</ref>