Closeup of a star

Over about two and a half days (August 16-18, 2007), the Sun's prominences were seen in extreme ultraviolet light by the Ahead spacecraft.

video

Prominences are clouds of cooler gases controlled by powerful magnetic forces that extend above the Sun's surface. Look carefully and you can sometimes see the gases arcing out from one point and sliding above the surface to another point.

In an 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.

But did you know you could put you hand in a bucket of sun and not even feel any heat? Temperature is a measure of the energy in a substance (the speed of the molecules), but the sun at the surface is so diffuse that the few fast moving molecules wouldn't even be noticeable.

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