This image shows an active region of the Sun. The National Solar Observatory, Sacramento Park, CA, made it using a special telescope. This image shows plage, areas of brightness and filaments, gas clouds above the Sun’s surface. NSO uses pictures of the Sun like this to help forecast spaceweather.
Click on image for full size
Image courtesy of the National Solar Observatory at Sacramento Peak

The Chromosphere

Above the photosphere is the chromosphere, a region about 2500 kilometers thick. Just prior to and just after the peak of a total solar eclipse , the chromosphere appears as a thin reddish ring. The conspicuous color of the chromosphere (compared to the mostly white corona) led to its name (meaning ``color sphere.'') The chromosphere is most easily viewed in emission lines such as Hydrogen alpha, where bright regions known as plages, and dark features called filaments are visible. Filaments are the name given to prominences when they are seen on the solar disk. Spicules are visible in the chromosphere on the limb of the sun. They are jets of plasma shooting up from supergranule boundaries.

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