NASA - National Aeronautics and Space Administration

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This week STEREO observed a nice gathering of solar prominences in profile as they twisted, stretched and floated just above the solar surface. Over about two and a half days (August 16-18, 2007), the prominences were seen in extreme ultraviolet light by the Ahead spacecraft. Prominences are clouds of cooler gases controlled by powerful magnetic forces that extend above the Sun’s surface. The careful observer can sometimes see the gases arcing out from one point and sliding above the surface to another point. In the most interesting sequence near the end of the clip, the upper prominence seems to arch away into space. Such sequences serve to show the dynamic nature of the Sun.