Caldwell 11 on:
[Wikipedia]
[Google]
[Amazon]
NGC 7635, also known as the Bubble Nebula, Sharpless 162, or Caldwell 11, is an H II region
With an 8 or telescope, the nebula is visible as an extremely faint and large shell around the star. The nearby 7th magnitude star on the west hinders observation, but one can view the nebula using averted vision. Using a 16 to scope, one can see that the faint nebula is irregular, being elongated in the north south direction.
NGC7635 The Bubble Nebula
*
Bubble Nebula at Constellation Guide
{{Portal bar, Astronomy, Stars, Outer space H II regions Emission nebulae Cassiopeia (constellation) 7635 Sharpless objects 011b Astronomical objects discovered in 1787
emission nebula
An emission nebula is a nebula formed of ionized gases that emit light of various wavelengths. The most common source of ionization is high-energy ultraviolet photons emitted from a nearby hot star. Among the several different types of emissio ...
in the constellation Cassiopeia. It lies close to the direction of the open cluster
An open cluster is a type of star cluster made of up to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, an ...
Messier 52. The "bubble" is created by the stellar wind from a massive hot, 8.7 magnitude
Magnitude may refer to:
Mathematics
*Euclidean vector, a quantity defined by both its magnitude and its direction
*Magnitude (mathematics), the relative size of an object
*Norm (mathematics), a term for the size or length of a vector
*Order of ...
young central star, SAO 20575 ( BD+60°2522). The nebula is near a giant molecular cloud
A molecular cloud, sometimes called a stellar nursery (if star formation is occurring within), is a type of interstellar cloud, the density and size of which permit absorption nebulae, the formation of molecules (most commonly molecular hydroge ...
which contains the expansion of the bubble nebula while itself being excited by the hot central star, causing it to glow. It was discovered in 1787 by William Herschel
Frederick William Herschel (; german: Friedrich Wilhelm Herschel; 15 November 1738 – 25 August 1822) was a German-born British astronomer and composer. He frequently collaborated with his younger sister and fellow astronomer Caroline ...
. The star BD+60°2522 is thought to have a mass of about .
Amateur observation
With an 8 or telescope, the nebula is visible as an extremely faint and large shell around the star. The nearby 7th magnitude star on the west hinders observation, but one can view the nebula using averted vision. Using a 16 to scope, one can see that the faint nebula is irregular, being elongated in the north south direction.
See also
*Lists of nebulae
A ''list'' is any set of items in a row. List or lists may also refer to:
People
* List (surname)
Organizations
* List College, an undergraduate division of the Jewish Theological Seminary of America
* SC Germania List, German rugby unio ...
Notes
References
* * * * * * *External links
NGC7635 The Bubble Nebula
*
Bubble Nebula at Constellation Guide
{{Portal bar, Astronomy, Stars, Outer space H II regions Emission nebulae Cassiopeia (constellation) 7635 Sharpless objects 011b Astronomical objects discovered in 1787