NGC 1999, a nebula in the constellation of Orion is an example of a reflection nebula. like fog around a street lamp, a reflection nebula shines only because the light from an imbedded source illuminates its dust. The nebula dose not emit any visible light of its own. NGC 1999 lies close to the famous Orion Nebula, about 1500 light years from Earth ina region of our Milky way galaxy where new stars are being formed actively. NGC 1999 was discovered two centuries ago by Sir William Herschel and his sister caroline, and was later catalogued in the 19th century as object 1999 in the New General Catalogue.
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