A screenshot from a video showing a solar flare erupting from the sun on Aug. 12, 2013. (Credit: NASA) Click on the screenshot of the video above to watch intense radiation explode in a solar flare recorded yesterday by a NASA spacecraft. As solar flares go, this one was medium in size — and not anything to worry about. No significant disruptions to systems here on Earth are expected from the radiation blasted out into space by the M1.5 class flare, according to the Space Weather Prediction Center. (You can get the latest SWPC forecast here.) All the same, watching an explosion like this unfold in closeup can be a humbling experience, especially when you realize that the area from which the flare erupted is probably bigger than our whole planet. The video, from NASA's Solar Dynamics Observatory, starts with a wide view of the sun. As it progresses, it zooms in to a super-closeup, along the way showing the flare in different wavelengths of light that highlight various characteristics of the sun and its magnetic field. What I like most about the video is that it helps illustrate the mechanisms behind solar flares. In the closeup views, look for the glowing loops. These show where lines of magnetism have bottled up hot, glowing plasma in the sun's corona. A solar flare like the one seen in the video erupts when adjacent magnetic field lines converge and connect, resulting in the explosive release of pent up energy. You can watch an animation of the process at about 1 minutes and 20 seconds into this video, which documents the highest energy light ever recorded from a solar flare: http://www.youtube.com/watch?v=4o7H0gww56I Yesterday's flare was just one of the things of interest happening on the sun. Another is a continuing coronal hole.
(Image: NASA/SDO) Click on the thumbnail at right to see a picture of it taken just today by the Solar Dynamics Observatory spacecraft. The hole is the dark blue region toward the top of the sun. Corey Powell, my fellow blogger here at Discover, and former editor-in-chief of the magazine, has just written an excellent piece explaining this dramatic phenomenon in detail. So if you're as fascinated about the sun as I am, check out his post.