The layer of the sun that corresponds to the solar surface viewed in white light or the region from which light escapes from the sun into space.
2. The intensely bright gaseous outer layer of a star, especially the sun.The photosphere is often marked by large, dark patches called "sunspots" and faculae. The faculae are groups of small shining spots on the surface of the sun which are brighter than the other parts of the photosphere.
About 300 kilometers or 200 miles deep, the photosphere consist of incandescent gas at a temperature of 5,800 Kelvin (5,530° Celsius or 9,980° Fahrenheit).
Kelvin is the basic unit of thermodynamic temperature adopted under the Systeme International d'Unites.
Rising cells of hot gas produce a mottling of the photosphere known as granulation, each granule being about 1,000 kilometers or 620 miles in diameter.