Wolf-Rayet Star WR 134

WR 134 is a Wolf-Rayet star located at about 6000 light years in constellation Cygnus. Wolf-Rayet stars are very bright (hundreds of thousands of times brighter than the Sun) and massive (more than 20 solar masses) variable stars that emit most of their energy in the ultraviolet and X-ray bands. These stars are quite rare: only a few hundreds of them are known to date.

Wolf-Rayet stars are often surrounded by stellar-wind-formed nebulae, and WR 134 is one such case. The faint nebula surrounding it emits mainly in the OIII band and sports a lot of fine detail. Moreover, the fact of being located in an Ha-rich region of the sky makes for a nice contrast between its greenish-bluish nebula and the bright red surrounding regions. All this makes WR 134 a beautiful and particular deep-sky astrophotography target.

The image that comes with this post is a long-term project that kept me busy for most of the summer of 2023, from July to September. Exposure details: Ha 195 x 10 min, OIII 195 x 10 min, RGB 40 x 5 min each for a total exposure of about 75 hours acquired with a QHY163M CMOS mono camera though a 10-inch f/8 GSO RC and a reducer yielding  focal length of 1370 mm. Unfortunately my narrowband filters (the OIII in particular) produce nasty halos around bright stars that are really tough to get rid of during post-production. Additionally, the CMOS camera I used is not really bleeding-edge technology. Anyway I hope you’ll enjoy my image!

Many thanks to Edoardo Radice for his invaluable help in processing this image.