Thor's Helmet is a rare example of a Wolf-Rayet star. Around 40 times the mass of our Sun, it is young and burning extremely brightly - a blue supergiant - and generates a stellar wind that blasts outwards at millions of kilometres per hour. Burning this brightly and shedding this much material, it is thought that Wolf-Rayet stars are seen in a brief stage of evolution before exploding as a supernova.
Credit: Image made in visible light by Jean-Charles Cuillandre for the Canada-France-Hawaii Telescope Corporation.
Download High Res Tif and Caption (29.6 MB)