emission nebula

American  

noun

Astronomy.

1. a bright diffuse nebula that emits light as a result of ionization of its gas atoms by ultraviolet radiation, as the Orion Nebula, planetary nebulae, and supernova remnants, as the Crab Nebula.

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emission nebula British  

noun

1. a type of nebula that emits visible radiation See nebula

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emission nebula Scientific  

/ ĭ-mĭsh′ən /

1. A nebula that absorbs ionizing ultraviolet radiation from nearby hot stars or star remnants and reemits it as visible light. HII regions, planetary nebulae, and nebulae created by the explosion of supernovae are different kinds of emission nebulae.

2. See more at nebula

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