Mark H
"It’s a stunning look at what is known as Thor’s Helmet. This helmet-shaped feature is an emission nebula is located in the constellation of Canis Major, about 15,000 light years from Earth. The nebula is a large expanding bubble illuminated by a central star in its last stage of life — a massive Wolf-Rayet star which is shedding its outer layers of gas at an extremely high rate due to intense radiation pressure. Wolf-Rayet stars are thought to represent a brief stage of evolution near the end of life for giant super massive stars; the last unstable phase before the star explodes as a brilliant supernova. The nebula is some 30 light years in diameter is embedded among a dense star field consisting of thousands of multi-colored stars, adding more beauty to the scene." - Mark H from Bookmarklet