The Crescent

This strange and difficult to find nebula in the constellation Cygnus, is highly unusual in many ways. It was formed in a manner similar to that which formed most planetary nebulas, but only a little different. The brighter star towards the center is what is known as a Wolf-Rayette star. There are fewer than 150 of these stars known. These stars are young hot supergiants that continually blow off their gaseous mass in a form of continual Nova. The reasons behind this are not totally known, as most stars do this sort of thing towards the end of their existence.