facula

American  

[fak-yuh-luh] / ˈfæk jə lə /

noun

Astronomy.

• faculae
  plural

1. an irregular, unusually bright patch on the sun's surface.

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facula British  

/ ˈfækjʊlə /

noun

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

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facula Scientific  

/ făk′yə-lə /

• faculae
  plural

1. 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.

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Other Word Forms

Derived Forms

• facular
  adjective

Inflected Forms

Nouns

• faculae
  plural

Etymology

Origin of facula

1700–10; < Latin: little torch, equivalent to fac- (stem of fax ) torch + -ula -ule

Example Sentences

See Examples For:

facula faculae

He considers it indeed "highly probable that the preparatory sign of a new spot is always a small, bright patch of facula."

From A Popular History of Astronomy During the Nineteenth Century Fourth Edition by Agnes M. (Agnes Mary) Clerke

"In addition to the contamination from stellar spots and faculae, we saw a stellar flare, an unpredictable event during which the star looks brighter for several minutes or hours," said Lim.

From Science Daily ● Sep. 25, 2023

Stellar contamination refers to the influence of the star's own features, such as dark spots and bright faculae, on the measurements of the exoplanet's atmosphere.

From Science Daily ● Sep. 25, 2023

What’s more, detailed observations from orbiting solar telescopes have shown that the small faculae pump out more energy per unit surface area than the larger ones already known to disappear along with the sunspots.

From Science Magazine ● May 26, 2011

So if the small faculae start to fade, too, that would have an even stronger effect on the total energy production of the sun.

From Science Magazine ● May 26, 2011

When the ascending currents are powerful, they create those appearances which astronomers designate the nuclei, the penumbrae, the faculae.

From The Story of the Herschels by Anonymous