The wonderful astrophotographer César Cantú takes amazing pictures of the sky, and his shots of the Sun are truly cool. On Wednesday, August 8, 2012, he took this image of the Sun and a sunspot called Active Region 1524:
The Sun is a 1970s orange shag carpet! Actually, César used an Hα filter, which blocks almost all the light from the Sun except for a very narrow slice of color where hydrogen emits light, and in fact this is preferentially given off by hydrogen under the sway of magnetic fields on the Sun, so this image accentuates magnetic activity. You can see lots of structure like the sunspots and the plasma flowing along magnetic fields - especially along the Sun's edge, where they're called prominences. The Sun looks amazingly different depending on how you look at it. Far from being a featureless white disk, it actually has detail all the way down to the resolution of our best telescopes. The surface of the Sun is fiendishly complex, and the amount to understand is equally daunting. And, as usual with astronomy, with this complexity comes astonishing beauty.
Image credit: César Cantú, used with permission.