Emission-nebula
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.
noun
1.
a type of nebula that emits visible radiation See nebula
emission nebula
(ĭ-mĭsh’ən)
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. See more at nebula.
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- Emissive
[ih-mis-iv] /ɪˈmɪs ɪv/ adjective 1. serving to emit. 2. pertaining to .
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[em-uh-siv-i-tee, ee-muh-] /ˌɛm əˈsɪv ɪ ti, ˈi mə-/ noun, Thermodynamics. 1. the ability of a surface to emit radiant energy compared to that of a black body at the same temperature and with the same area. /ɪmɪˈsɪvɪtɪ; ˌɛm-/ noun 1. a measure of the ability of a surface to radiate energy; the ratio of the […]
- Emit
[ih-mit] /ɪˈmɪt/ verb (used with object), emitted, emitting. 1. to send forth (liquid, light, heat, sound, particles, etc.); discharge. 2. to give forth or release (a sound): He emitted one shrill cry and then was silent. 3. to utter or voice, as opinions. 4. to issue, as an order or a decree. 5. to issue […]