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Active regions on the Sun are places where the Sun's magnetic field is especially strong.
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Windows to the Universe original artwork by Randy Russell using an image from NASA's TRACE (Transition Region and Coronal Explorer) spacecraft.

Active Regions on the Sun

An active region on the Sun is an area with an especially strong magnetic field. Sunspots frequently form in active regions. Active regions appear bright in X-ray and ultraviolet images. Solar activity, in the form of solar flares and coronal mass ejections (CMEs), is often associated with active regions.

Last modified January 19, 2010 by Randy Russell.

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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