APOD 3.2

This cosmic bubble is located toward the constellation Canis Major (the Big Dog), surrounds a Wolf-Rayet star. A Wolf-Rayet (WR) stars are evolved, massive stars that lose mass rapidly by means of releasing very strong solar wind. This solar wind that is released is making this cosmic bubble, labeled Sharpless 308, expand. It is already larger than the full moon to a viewer, which corresponds to being 60 light-years in diameter. Emission lines captured from this massive image are dominated by ionized oxygen. This photo pertains to the chapters we are currently studying, chapters 17 and 18, which have to do with stars and identifying their stellar spectra.