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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 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