I do always enjoy Phil Plait’s blog. In line with the ongoing discussion on this blog, I thought I’d share something pretty cool from his:
Wow! So what are we seeing here?
SDO views the Sun in many wavelengths, and in this case we’re looking at ultraviolet light form the Sun so energetic it’s almost X-rays. The bright spot is actually a sunspot! They’re dark in the kind of light we see with our eyes* but can be very bright at other wavelengths. Sunspots are regions of intense magnetic field concentration; magnetic loops arc out of the spot, reach into space, then head back down. They seethe with vast amounts of energy, which can be released explosively under some conditions.
That’s what happened here. The magnetic field loops in Sunspot 1123 suddenly and cataclysmically released all their energy in the early morning of November 12, blasting it outward as a solar flare — you can see that as the intense flash of light coming from the bright region in the center of the video. This explosive event also launched a streamer of plasma off the Sun’s surface, flowing outward along the Sun’s magnetic field. Although the plasma is very hot, we see it silhouetted against the Sun’s surface, so it looks dark. This type of streamer is called a filament (had we seen it against the darkness of space, it would look bright, and be called a prominence). You can see it heading roughly in our direction at the end of the video. Don’t worry though, it won’t hit us!
Definitely continue reading. It’s pretty awesome (but also kinda scary!).