I figure that since about half of the forces at play in an aurora show is not from this world, this thread would be a good place to start a discussion of the northern (and southern) lights.
I grew up in central Wisconsin and got to see the northern lights on occasion as a kid. One of my most memorable shows (also the first time I saw them) was during the huge geomagnetic storm back in '89. I remember the entire northern half of the sky (and to some extent, past overhead into the southern half!) was red. I didn't know at the time that red aurorae are pretty rare - the result of particularly high-energy solar wind ions. I don't recall seeing much motion in the lights that night, basically just huge wall of diffuse red light - much like AJ described in my status (but red instead of green).
The best show I ever saw was also in central Wisconsin - back during the storm in '02. That was the first time I really
saw motion in the lights. Huge lightning-like spires that erupted from the main corona, giant patches of ribbons that looked like bright green silk fabric rippling in a breeze, and the trademark curtains that undulated and flared for hours. My buddies and I were hanging out in town and could see them plain as day even under the city street lights. We decided to head out of town and watch from the roof of my friend's barn and that's right where we stayed, jaws dropped, for the next three hours.
I've seen them about a dozen times in my life and since my wife and I moved to northern Minnesota in June, I've already seen them three times. I expect to add many more nights out under the magnetosphere, quietly whispering "holy shit!" and the occasional "what the fuuuuuuuuck
!" to myself in the years to come.
If anyone else has seen some particularly good show, let's hear about them. Because, as anyone who's seen a good show knows, pictures just don't do them justice!
Here are some forecast tools to help plan when to look:
The first link has a ton of information (yay, NOAA!), this is one of their forcast models that will be more useful for beginners: