NGC 2359 Thor's Helmet
Distance Aprox: 11,960 light-years
Diameter: 30 light-years
Constellation: Canis Major
The central star is the Wolf-Rayet star WR7, an extremely hot star thought to be in a brief pre-supernova stage of evolution. It is similar in nature to the Bubble Nebula, but interactions with a nearby large molecular cloud are thought to have contributed to the more complex shape and curved bow-shock structure of Thor's Helmet.
The nebula has an overall bubble shape, but with complex filamentary structures. The nebula contains several hundred solar masses of ionised material, plus several thousand more of unionised gas. It is largely interstellar material swept up by winds from the central star, although some material does appear to be enriched with the products of fusion and is likely to come directly from the star.
Taken 2/17/18 in Chiefland Florida by Russell Kille on a CPC 1100 with Hyperstar @ F2 and ZWO ASI294MC Pro camera
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