Astronomy Picture of the Day

Explanation: One of the most spectacular solar sights is an explosive flare. In 2011 June, the Sun unleashed somewhat impressive, medium-sized solar flare as rotation carried active regions of sunpots toward the solar limb. That flare, though, was followed by an astounding gush of magnetized plasma -- a monster filament seen erupting at the Sun's edge in this extreme ultraviolet image from NASA's Solar Dynamics Observatory. Featured here is a time-lapse video of that hours-long event showing darker, cooler plasma raining down across a broad area of the Sun's surface, arcing along otherwise invisible magnetic field lines. An associated coronal mass ejection, a massive cloud of high energy particles, was blasted in the general direction of the Earth,and made a glancing blow to Earth's magnetosphere.