Stacked Loops: Three Flavors Three active regions lined up vertically and each of the loop structures above them twisted differently when viewed in extreme ultraviolet light (Oct. 15 - 17, 2011). The high arching loops of the top active region seemed to lean to the north; the one beneath it clearly coiled to the south; at the bottom, one spread mostly upright and to the left and right as well. The loops are tracing particles spiraling along magnetic field lines that have emerged from underneath the Sun's surface. While the movie shows that the loops shifted and changed over 2.5 days, the basic structure of all three remained very much the same. It is not common to see active regions so neatly aligned atop one another.