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These two large prominences (lower right and lower left) erupted from the Sun in March 2003. This ultraviolet image was captured by the SOHO spacecraft.
Click on image for full size
Image courtesy SOHO (NASA & ESA).

Solar Prominence

Large impressive loop-like structures on the edge of the solar disk sometimes stand out brightly against the dark background of space. Though these structures, called "prominences", appear to be very bright and hot, they are actually hundreds of times cooler and denser than the surrounding gases in the Sun's corona or outermost atmosphere.

Filaments are dark string-like features that snake across regions of the solar disk. They are actually prominences that are silhouetted against the much brighter solar surface.

Filaments and prominences can remain stable for weeks or even months. Then, without warning, these structures can erupt and blow large amounts of gas and plasma out into space. Erupting prominences are closely associated with an important space weather event called a Coronal Mass Ejection (CME).

Last modified August 17, 2005 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