The Wizard Nebula ( or Sharpless 142) is a diffuse nebula surrounding the developing open star cluster NGC 7380. Discovered by Caroline Herschel in 1787, its nebulosity at the time was not noted. Later, when the nebulosity was discovered, it was given the designation Sharpless 142.
Visually, the interplay of stars, gas, and dust has created a shape that appears to some like a fictional medieval sorcerer. The NGC 7380 spans about 10,500 light-years and lies within our Milky Way Galaxy, about 8,000 light years away in the constellation of Cepheus. It is moving toward us at 34.13 kilometers per second.
At mag. 7.2, it is a loose collection of maybe 125 stars total. (NGC 7380 is in the top right quadrant). This kind of nebulae are the birthplace of stars. They are formed when very diffuse molecular clouds begin to collapse under their own gravity, often due to the influence of a nearby supernova explosion. The cloud collapses and fragments, sometimes forming hundreds of new stars. The newly-formed stars ionize the surrounding gas to produce an emission nebula.
The star cluster is embedded in the nebula, sometimes called the Wizard Nebula, which spans some 110 light-years. This bright, active star-forming region is part of a much larger molecular cloud in Cepheus, called NGC 7380E, which total mass is estimated to be 6,000-15,000 solar masses. This image was created in the Hubble Space Telescope from the emission of ionized elements, represented by the yellow Sulfur, green Hydrogen and blue Oxygen.
Sources: Nasa, Astronomy News, Space.