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photosphere




structure of the Sun
The visible surface of the Sun or some other star; it lies just below the chromosphere and just above the convective zone and has a temperature of about 6,000 K. The photosphere ends (and the chromosphere begins) at about the place where the density of negative hydrogen ions falls too low to result in appreciable opacity.

Almost all the features of the Sun's visible-light spectrum originate in the photosphere, including the dark Fraunhofer lines. It has a texture known as granulation, caused by rising convection cells of hot gas, and is the location of sunspots, faculae, and filligrees – all associated with strong magnetic fields.


Related category

   • SOLAR TOPICS