The haunting “Skull Nebula”, planetary nebula (NGC 246) surrounds a dying star some 1,600 light-years away in the constellation Cetus. Expanding over a period of thousands of years, nebula is the outer atmosphere of a once sun-like star. The expanding outer atmosphere is interacting with the gas and dust in the interstellar medium, while the star itself, the fainter member of the binary star system seen at the nebula’s center, is entering its final phase of evolution, becoming a dense, hot white dwarf.  Image Credit: NASA

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Image of the Day: The Ghostly "Skull Nebula"