Changes

==History==

==History==

The nebula was discovered by a [[French]] astronomer, Pierre Méchain, on Febuary 16, 1781.<ref name=seds>[http://www.messier.seds.org/m/m097.html Messier 97] from messier.seds.org</ref> Méchain later informed [[Charles Messier]] of his discovery, who then added it to his [[Messier catalogue|catalogue]]. Messier's description of M97 includes descriptions of two other deep sky objects. These two galaxies were retroactively added to Messier's catalogue after his death as [[Messier 108]] and [[Messier 109]] by Owen Gingerich in 1953.<ref name=messier-objects/> Admiral William Henry Smyth was the first person to identify the Owl nebula as a [[planetary nebula]] in 1837.<ref name=messier-objects/> William Parsons the 3rd Earl of Rosse (sometimes referred to as Lord Rosse) gave the nebula its common name, the "Owl nebula".<ref name=freestarcharts/> The gaseous envelope surrounding central star was first noticed by William Huggins in his study of the nebula's spectrum.

The nebula was discovered by a [[French]] astronomer, Pierre Méchain, on February 16, 1781.<ref name=seds>[http://www.messier.seds.org/m/m097.html Messier 97] from messier.seds.org</ref> Méchain later informed [[Charles Messier]] of his discovery, who then added it to his [[Messier catalogue|catalogue]]. Messier's description of M97 includes descriptions of two other deep sky objects. These two galaxies were retroactively added to Messier's catalogue after his death as [[Messier 108]] and [[Messier 109]] by Owen Gingerich in 1953.<ref name=messier-objects/> Admiral William Henry Smyth was the first person to identify the Owl nebula as a [[planetary nebula]] in 1837.<ref name=messier-objects/> William Parsons the 3rd Earl of Rosse (sometimes referred to as Lord Rosse) gave the nebula its common name, the "Owl nebula".<ref name=freestarcharts/> The gaseous envelope surrounding central star was first noticed by William Huggins in his study of the nebula's spectrum.

==Properties and Structure==

==Properties and Structure==

The nebula distance of some 2,030 [[light year]]s means its apparent size of 3.4x3.3 arc minutes corresponds to a physical [[radius]] of 0.91 ly.<ref name=constellation-guide>[http://www.constellation-guide.com/owl-nebula-messier-97/ Owl nebula: Messier 97] from constellation-guide.com</ref> There is great uncertainty in the exact distance to the nebula, with distances varying from 1,300 to 12,000 light years.<ref name=seds/> The gaseous component of the nebula has a mass estimated to be around 0.13-0.15 solar masses,<ref name=messier-objects/><ref name=seds/> though estimates vary, and is currently expanding at a rate somewhere between 27-39 km/s<ref name=constellation-guide/> The nebula is notably brighter than other planetary nebula, such as the [[Ring nebula]] of the [[Little dumbbell nebula]].

The nebula distance of some 2,030 [[light year]]s means its apparent size of 3.4x3.3 arc minutes corresponds to a physical [[radius]] of 0.91 ly.<ref name=constellation-guide>[http://www.constellation-guide.com/owl-nebula-messier-97/ Owl nebula: Messier 97] from constellation-guide.com</ref> There is great uncertainty in the exact distance to the nebula, with distances varying from 1,300 to 12,000 light years.<ref name=seds/> The gaseous component of the nebula has a mass estimated to be around 0.13-0.15 solar masses,<ref name=messier-objects/><ref name=seds/> though estimates vary, and is currently expanding at a rate somewhere between 27–39 km/s<ref name=constellation-guide/> The nebula is notably brighter than other planetary nebula, such as the [[Ring nebula]] of the [[Little dumbbell nebula]].

Spectrums of the nebula have shown it contains a variety of different [[element]]s, including: [[hydrogen]], [[helium]], [[nitrogen]], [[oxygen]] and [[sulfur]].<ref name=messier-objects/> The [[density]] of particles within the nebula is believed to be around 100 particles per cubic centimetre.  

Spectrums of the nebula have shown it contains a variety of different [[element]]s, including: [[hydrogen]], [[helium]], [[nitrogen]], [[oxygen]] and [[sulfur]].<ref name=messier-objects/> The [[density]] of particles within the nebula is believed to be around 100 particles per cubic centimetre.