A dark prominence can be seen crossing right underneath a coronal loop as they both rotate into view (Aug. 26 - 28, 2012). Prominences are long strands of cooler gases that float above the Sun's surface. The loops that we see here in extreme ultraviolet light are magnetic field lines being traced by spiraling particles above active regions. It is not uncommon for a prominence to stretch under these connecting loops, but it is harder to see unless they are in profile, as they are here. Finding these kinds of smaller details are only possible to see clearly with the very high resolution of SDO's imagers. The video covers almost two days of activity.
Search Tag(s): 171, active regions, prominence, limb