An Etymological Dictionary of Astronomy and Astrophysics
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A bright area of the → photosphere of the Sun visible in white light and best seen near the solar limb, although they occur all across the Sun. Faculae raise several hundred kilometers above the photosphere and are associated with → sunspots. They often appear immediately before the formation of a sunspot group and remain visible for several days or weeks after the disappearance of the spots. Faculae are formed when a strong magnetic field heats a region of the photosphere to higher temperatures than the surrounding area.

Facula, from L. fac-, fax "torch" + -ula, → -ule.

Perisk, periska, biriske in Lori, Laki, and Kurd. dialects "spark" (Lârestâni pelita), probably related to Lori porpor "blazing charcoal," Gilaki bur, biur "smokeless red fire;" cf. Tokharian por, puwar "fire;" Gk. pyr "fire;" Hitt. pahhur "fire;" Skt. pū- "to cleanse;" E. fire; O..E. fyr, from P.Gmc. *fuir (cf. O.N. fürr, M.Du. vuur, Ger. Feuer); PIE base *paewr- "fire."

Solar faculae occurring in regions of high heliographic latitudes. They are smaller than the main-zone faculae; their shape is point-like or oval. Their lifetimes range from a few minutes to some hours, but the decisive difference from the main-zone faculae lies in their activity cycle. When spots and faculae of the main zone are at minimum, the polar faculae have their maximum activity, and vice versa.

→ polar; → facula.