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chromosphere
chromosphere [Gr.,=color sphere], layer of rarefied, transparent gases in the solar atmosphere; it measures 6,000 mi (9,700 km) in thickness and lies between the photosphere (the sun's visible surface) and the corona (its outer atmosphere).
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"chromosphere." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "chromosphere." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1E1-chromosp.html "chromosphere." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-chromosp.html |
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chromosphere
chromosphere A region of a star's atmosphere above its photosphere. The Sun's chromosphere extends from the temperature minimum, some 500 km above the base of the photosphere, outwards by 9000 km where it merges with the corona. For the first 1500 km the chromosphere is more or less continuous, but above this it breaks up into jagged spicules. The temperature of the chromosphere rises from 4400 K at 500 km to about 6000 K at 1000–2000 km. There is a rapid rise to coronal temperatures at heights of about 2500 km (the transition region), the exact height depending on the strength of the local magnetic field. At the top of the chromosphere, the density is a millionth of its value at the bottom. Immediately before and after a total solar eclipse, the chromosphere is visible either as a crescent or a diamond ring, with red coloration due to Hα emission from which it takes its name (meaning ‘colour sphere’). Outside eclipses it is visible in Hα and calcium K-line filtergrams, and from space in ultraviolet emission lines. The presence of chromospheres in nearby cool dwarf stars is deduced from similar emissions.
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"chromosphere." A Dictionary of Astronomy. 1997. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "chromosphere." A Dictionary of Astronomy. 1997. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O80-chromosphere.html "chromosphere." A Dictionary of Astronomy. 1997. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-chromosphere.html |
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chromospheric network
chromospheric network A global pattern in the Sun's chromosphere, formed by bright and dark mottles visible in Hα light or the calcium H and K lines. The network marks regions of strong magnetic field, and coincides with boundaries of the supergranulation on the photosphere below. Coarse bright mottles outline the network. Fine mottles, both dark and bright, are arranged in clusters, with their bases rooted in coarse mottles. These small mottles are probably spicules seen against the Sun's disk. The network extends into the transition region above the chromosphere, but fans out into the corona and can no longer be detected there.
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Cite this article
"chromospheric network." A Dictionary of Astronomy. 1997. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "chromospheric network." A Dictionary of Astronomy. 1997. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O80-chromosphericnetwork.html "chromospheric network." A Dictionary of Astronomy. 1997. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-chromosphericnetwork.html |
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chromosphere
chro·mo·sphere / ˈkrōməˌsfi(ə)r/ • n. Astron. a reddish gaseous layer immediately above the photosphere of the sun or another star. Together with the corona, it constitutes the star's outer atmosphere. DERIVATIVES: chro·mo·spher·ic / ˌkrōməˈsfi(ə)rik; -ˈsferik/ adj. |
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"chromosphere." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "chromosphere." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O999-chromosphere.html "chromosphere." The Oxford Pocket Dictionary of Current English. 2009. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-chromosphere.html |
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chromosphere
chromosphere Layer of the Sun's atmosphere between the photosphere and the corona. It is c.10,000km (6000mi) thick and is briefly visible near the beginning and end of a total solar eclipse as a spiky red rim around the Moon's disk. At its base the temperature of the chromosphere is c.4000K, rising to 100,000K at the top.
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"chromosphere." World Encyclopedia. 2005. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "chromosphere." World Encyclopedia. 2005. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O142-chromosphere.html "chromosphere." World Encyclopedia. 2005. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-chromosphere.html |
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