Thor’s Helmet Nebula - NGC 2359 (also known as Thor's Helmet) is an emission nebula in the constellation Canis Major. The nebula is approximately 15,000 light-years away and 30 light years in size. The central star is the Wolf-Rayet star HD 56925, an extremely hot giant thought to be in a brief, pre-supernova stage of evolution
This photo from NASA's Hubble Space Telescope shows an ominous pillar of gas and dust known as the Cone Nebula. The image shows the top portion of the nebula that is 2.5 light years in height. The Cone Nebula is 2,500 light-years from Earth in the Monoceros constellation. The red halo of light seen around the pillar is caused when ultraviolet radiation causes hydrogen gas in the nebula to glow.