chromosphere

chromospheric /kroh'meuh sfer"ik, -sfear"-/, adj.
/kroh"meuh sfear'/, n. Astron.
1. a scarlet, gaseous envelope surrounding the sun outside the photosphere, from which enormous quantities of hydrogen and other gases are erupted.
2. a gaseous envelope surrounding a star.
[1865-70; CHROMO- + -SPHERE]

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Layer of the Sun's atmosphere, several thousand miles thick, above the photosphere and below the corona.

The chromosphere (literally "colour sphere") is briefly visible as a thin ring, red from hydrogen's emission spectrum, during solar eclipses when the photosphere is obscured by the Moon. At other times it can be observed only with special instruments. Its temperatures range from about 7,000 °F (4,000 °C) about 700 mi (1,100 km) above the photosphere, increasing with altitude to several hundred thousand degrees. Solar flares and solar prominences are mainly chromospheric phenomena.

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solar
      lowest layer of the Sun's atmosphere, several thousand kilometres thick, above the bright photosphere and below the extremely tenuous corona. Named by the English astronomer Joseph Norman Lockyer in 1868, the chromosphere (colour sphere) appears briefly as a bright crescent, red with hydrogen light, during solar eclipses when the body of the Sun is almost obscured by the Moon. Except during eclipses, it can be observed only with special instruments—i.e., the spectroheliograph or coronagraph. The lower chromosphere was formerly called the reversing layer because it was thought to be responsible for producing the dark lines of the solar spectrum that appear reversed against the bright continuous spectrum; actually the weak dark lines and bright continuum can be produced in essentially the same regions, stronger lines being produced at higher levels. The term reversing layer is now seldom used. The lower chromosphere is more or less homogeneous; the upper contains comparatively cool columns of ascending gas known as spicules, having between them hotter gas much like that of the corona, into which the upper chromosphere merges gradually. Temperatures in the chromosphere range from about 4,500 to 100,000 K, increasing with altitude. Solar flares and prominences are primarily chromospheric phenomena.

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Universalium. 2010.

Look at other dictionaries:

  • chromosphère — [ kromosfɛr; krɔmɔ ] n. f. • 1873; de chromo et sphère ♦ Astron. Partie superficielle extérieure de la couronne solaire. Protubérances de la chromosphère. ● chromosphère nom féminin (anglais chromosphere) Région de l atmosphère du Soleil ou d une …   Encyclopédie Universelle

  • Chromosphere — Chromosphère Chromosphère solaire visible en France lors de l éclipse totale de 1999 La chromosphère est la basse atmosphère du Soleil. C est une fine couche rose de gaz, transparente pour la lumière visible, située entre la photosphère et la… …   Wikipédia en Français

  • Chromosphère — solaire visible en France lors de l éclipse totale de 1999 La chromosphère est la basse atmosphère du Soleil. C est une fine couche rose de gaz, transparente pour la lumière visible, située entre la photosphère et la couronne solaire[1 …   Wikipédia en Français

  • Chromosphere — Chro mo*sphere, n. [Gr. ? color + E. sphere.] (Astron.) An atmosphere of rare matter, composed principally of incandescent hydrogen gas, surrounding the sun and enveloping the photosphere. Portions of the chromosphere are here and there thrown up …   The Collaborative International Dictionary of English

  • chromosphere — 1868, from chromo , from Gk. khroma color (see CHROMA (Cf. chroma)) + sphere. So called for its redness …   Etymology dictionary

  • chromosphere — [krō′məsfir΄] n. [ CHROMO + SPHERE] the pinkish, glowing region around a star, esp. the sun, between the hot, dense photosphere and the much hotter, tenuous corona chromospheric [krō′məsfer′ik] adj …   English World dictionary

  • Chromosphere — The Sun observed through a telescope with an H alpha filter …   Wikipedia

  • chromosphere — chromosfera statusas T sritis fizika atitikmenys: angl. chromosphere vok. Chromosphäre, f rus. хромосфера, f pranc. chromosphère, f …   Fizikos terminų žodynas

  • chromosphere — noun Date: 1868 the region of the atmosphere of a star (as the sun) between the star s photosphere and its corona • chromospheric adjective …   New Collegiate Dictionary

  • chromosphere — noun The faint pink extension of a stars atmospheric envelope between the corona and the photosphere …   Wiktionary

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