WR 134

 Wolf-Rayet (WR) stars are rare, highly luminous stars (thousands of times brighter than the Sun) with high surface temperatures. Population I WR stars have exhasted their hydrogen and are fusing helium in their cores. A subset of Population I are WNh stars. WNh stars are young, massive stars fusing hydrogen in their cores, but helium and nitrogen exposed at the star surface. A third group is composed of the central stars of planetary nebulae. These are sunlike stars that have ceased fusion leaving the carbon-oxygen core exposed.

WR 134, in the images below, has blown off an oxygen bubble (blue) that can be clearly seen against the backdrop of the reddish ionized hydrogen cloud and dark sky beyond. 400,000 times brighter than the Sun, WR 134 was one the first of this class of stars, discovered by Charles Wolf and Georges Rayet in 1867. They were identified by their unusual spectra of intense emission lines, rather than the more common absorbtion lines.

The first image below was processed by removing the stars, enhancing the nebula, and then adding the stars back. The second image is the starless version, showing subtleties of the nebula, along with a cropped starred and starless version. WR 134 is the second star from the left in the linear grouping of four stars to the right of the cropped image. I've also included the original image for those interested in seeing the difference processing makes.

Tech card: RASA 8, DS10C, NBZ filter. Approx 100 minutes of integration with 60 second subs.