The Surface Of The Sun

This is an example of a "running difference" image of the sun's
surface revealed by the TRACE satellite using its 171 angstrom filter.
This filter is specifically sensitive to iron ion (FE IX/X) emissions
and records a C3.3 flare and mass ejection in AR 9143 in 171Å
on 28 Aug. 2000. The flare activity is caused by increased
electrical activity as fast moving plasma sweeps over
surface ridges, resulting in increased electrical activity
on the windward side of the mountain ranges

http://www.thesurfaceofthesun.com/