On August 4 at about 04:00 UT, the Sun let loose with another big flare, this one ranking as an M 9.5 or so on the standard flare classification, bigger than the one earlier this week. It also triggered a coronal mass ejection, which means we may get some effects here on Earth.

First, the way-cool video:

[Set the resolution to 720p or 1080p for the best view. Note: In the video title I said this happened on August 3. It did, in my time zone! It was August 4th in Universal Time, however. Sorry about any confusion.]

This is in the far ultraviolet, where energetic events like these show up well. The bright regions are actually sunspots, which are dark to our eye but are pretty glowy in the UV. At 03:57 UT the magnetic field lines in the spot reconnected, starting a cascade that released all the energy they contained. This caused the flare that’s fairly obvious in the video. But you can also see material blasting away from the area, some falling back down. Finally, there are wispy tendrils of material arcing up that fade away.

What you don’t really see here ...