What Causes an Aurora?

I write a lot about aurorae, the lovely and eerie glowing lights at extreme latitudes caused when subatomic particles from the Sun are channeled down into the atmosphere by Earth's magnetic field. Whenever I do I always wind up having to write a brief explanation of how they work; that's the responsibility of a science writer. But my burden is now eased a bit thanks to this well-done video giving a solid overview: What I like about the video is that it covers the basics without giving too much d...