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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 Sunís surface. NSO uses pictures of the Sun like this to help forecast spaceweather.
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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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The Photosphere - the "Surface" of the Sun

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Sunspots

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF