solar plage

Plage (bright central feature) taken in the CaII K band on Jan. 6, 1980 at Sacramento Peak NSO.

A plage is a bright spot in the solar chromosphere, usually found in or near an active region such as a sunspot; the name is French (with a short "a") and means "beach." Plage, not to be confused with the photospheric faculae, are normally only visible in the monochromatic light of spectral lines, such as H-alpha or Ca II. They can last for several days and mark areas of nearly vertical emerging or reconnecting magnetic field lines. Plages were formerly known as flocculi. A plage corridor is a space in a plage lacking plage intensity and coinciding with a polarity inversion.