Astronomy Picture of the Day

Explanation: What do aurorae look like from above? Behold! From the ground, aurorae dance high above clouds, frequently causing spectacular displays. From space, they look a bit different. As the International Space Station (ISS) circles the Earth every 90 minutes, it sometimes sees aurorae below that are active on the night side. A one-hour time-lapse video showing aurorae from above was captured about two weeks ago from the orbiting ISS. The ISS -- and all objects in low Earth orbit -- will pass well above green aurorae but just a bit above red glowing aurorae. Auroral electron and proton streams are too thin to be a danger to the ISS, just as clouds pose little danger to airplanes. From orbit, as magnetic fields change, aurorae can appear to squiggle and crawl like giant snakes. The featured one-minute video was captured by French astronaut Sophie Adenot of the ISS Expedition 74 crew.