An emission nebula in the constellation Canis Major, its NGC designation is NGC2359. The star that is providing the energy to make the nebula glow is a Wolf-Rayet star (WR7). Such stars have entered a life phase when they have exhausted hydrogen and begin fusing helium atoms to make heavier elements like carbon. This particular WR star is thought to be nearing a stage when it might become a supernova. Thor’s Helmet is about 12K LY from Earth.
The image below is the composite of 29, 6-minute exposures taken on 1/16 and 1/17/22 at ISO3200 through my SV130mm F/5 astrograph using a quad-narrowband filter. The first image is modestly cropped, and the second much more so in order to better show the structure.
