It wasn’t exactly in the forecast, but then again, that’s how weather is sometimes. I was out with my class looking at Mars and the Orion Nebula Tuesday night (Feb. 14) about 9:30 p.m. CST when all at once a patch of aurora blossomed in the northeastern sky. It faded but then was replaced by another and another and then a few rays to boot. After we wrapped up our observing time, I drove out to a location with a good open horizon to the north and watched the display for nearly an hour.
Soft rays and rayed-arcs lolled about the north slowly coming and going. Nothing dramatic but the pale greens and shifting textures of the the aurora kept me put till my feet nearly froze. At best, rays and diffuse patches reached halfway up in the sky to touch the North Star.
It’s now just after midnight and there’s still some glow in the north. If you’re still up or live in the northern U.S. or southern Canada, it might be worth your while to give a look. Here’s the link for the Kp index, an indicator of activity in Earth’s magnetic field, and a second link for viewing the real-time auroral oval. I hope the lights continue to flare up during the night. There’s a possibility they’re connected to a coronal mass ejection from the sun on the 10th, but it’s still unclear. Whatever the reason, I’ll take aurora any way I can get it.
UPDATE: The aurora may appear again tonight for northerners, so keep an eye out. As far as what caused the Valentine’s Day aurora, it now appears it had to do with the direction of the magnetism blown out by the sun into the solar system. The magnetic field bound up in the solar wind pointed south, partly canceling the Earth’s northward-pointing field and allowing particles in the wind to penetrate the upper atmosphere and spark auroras. You can read more about the how it happens HERE.