NGC 2392 is known as Eskimo Nebula because of its singular shape. It's the most representative PN of Gemini constellation, it's a bright object and with a good angular dimension, that make it a good target also for medium-instruments. With large telescopes we can resolve the real structure of this nebula: its bright central star is surrounded by an inner shell structure,brighter and thinner, and then another concentric outer shell, more diffuse and with irregular brightness. This nebula has been hard studied by astronomers for 40 years, and now we know it's an elliptic structure elongated toward our visual direction with an angled jet. Outer shell is spread of low-ionization FLIERs (Fast Low Ionization Emission Regions), the typical filaments we see in any Eskimo image.
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