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Description:
The Dolphin Head Nebula, also known as Sharpless 2-308 (Sh2-308), is a striking emission nebula located approximately 4,530 light-years away in the constellation Canis Major. This expansive cosmic bubble spans about 60 light-years in diameter, making it appear slightly larger than the full Moon when observed from Earth.
At the heart of Sh2-308 lies EZ Canis Majoris, a massive Wolf-Rayet star with over 20 times the mass of our Sun. Wolf-Rayet stars are known for their intense stellar winds, which, in the case of EZ Canis Majoris, blow at speeds up to 1,700 kilometers per second. These powerful winds have swept up surrounding material, creating the nebula's distinctive bubble-like structure. The nebula's glow primarily results from ionized oxygen atoms, emitting a characteristic blue hue.
Formed approximately 70,000 years ago, the Dolphin Head Nebula offers insight into the late evolutionary stages of massive stars. EZ Canis Majoris is currently in a brief pre-supernova phase, and its eventual explosion will likely disperse the nebula's material into the interstellar medium.
