Bad Astronomy

Without Warning: Time Lapse of a Pink Aurora, With a Bonus

Time-lapse video of pink aurora and the ISS
The arcing path of the ISS punctuates the pink aurora over Crater Lake in May 2013.

Photo by Brad Goldpaint, used by permission

Over the weekend, I wrote about a surprise solar storm that sparked aurorae over the northern United States, including an amazing pink display photographed by Brad Goldpaint.

He took enough pictures of the event to create a phenomenal (if too short) time-lapse video of the event, including a surprise at the very end: a pass of the International Space Station.

An interesting thing happens around 40 seconds into the video: A series of white patches can be seen moving right to left. They look to be above the dark clouds (which move the opposite way). Brad brought them to my attention; I suspect these are just high-altitude clouds glowing softly, but I’m not sure. I am pretty sure they are not aurorae themselves, since they’re white. An aurora can be green, red, blue, purple, or pink, but white is a combination of colors that is, as far as I can tell, essentially impossible to create in this way. (It would need a very specific blend of those component colors, which is highly unlikely.) So I’m leaning toward them being clouds. Opinions?

Over the next few days there will be a great series of passes by the ISS over the United States. You can find out if you can see it by going to Heavens Above (have your latitude and longitude handy), or ISS Astroviewer, or the Real Time Satellite Tracker. It’s fun to watch it move across the sky, and knowing that there are six human beings on it right now.