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A picture of the Sun made with a special camera and telescope.
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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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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA