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facula

[fak-yuh-luh] /ˈfæk yə lə/
noun, plural faculae
[fak-yuh-lee] /ˈfæk yəˌli/ (Show IPA).
Astronomy
1.
an irregular, unusually bright patch on the sun's surface.
Origin
1700-1710
1700-10; < Latin: little torch, equivalent to fac- (stem of fax) torch + -ula -ule
Related forms
facular, adjective
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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Examples for facula
  • The sunspot at lower left and the nearby bright facula close to the limb were especially prominent.
British Dictionary definitions for facula

facula

/ˈfækjʊlə/
noun (pl) -lae (-ˌliː)
1.
any of the bright areas on the sun's surface, usually appearing just before a sunspot and subject to the same 11-year cycle
Derived Forms
facular, adjective
Word Origin
C18: from Latin: little torch, from fax torch
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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facula in Science
facula
  (fāk'yə-lə)   
Plural faculae (fāk'yə-lē')
A bright, cloudlike structure on the Sun's surface, ascending several hundred kilometers above the photosphere and often associated with sunspots. Faculae are formed when a strong magnetic field heats a region of the photosphere to higher temperatures than the surrounding area. They occur all over the Sun but are usually only visible near the limb (the outer edge of the Sun's apparent disk), where the photosphere appears dimmer than in the center.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Encyclopedia Article for facula

in astronomy, bright granular structure on the Sun's surface that is slightly hotter or cooler than the surrounding photosphere. A sunspot always has an associated facula, though faculae may exist apart from such spots. Faculae are visible in ordinary white light near the Sun's limb (apparent edge), where the photospheric background is dimmer than near the centre of the disk. The extensions of faculae up into the chromosphere become visible over the entire disk in spectroheliograms taken at the wavelengths of hydrogen or ionized calcium vapour. When seen thus away from the limb, they are called chromospheric faculae or plages.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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11
14
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