Spiral Aurora

That spiral shape is fascinating. Aurorae are formed when charged particles from the Sun slam into the Earth’s magnetic field and interact with it. They’re channeled down into our atmosphere, guided by the Earth’s field, and the shape of the aurora reflects the underlying magnetic field lines. They take on fantastic shapes, including spirals like this, but I don’t think I’ve ever seen curled in a way so well-defined and crisp.

Via: Discover Magazine