Photo: Solar-wind blast

On Monday, Aug. 22, a pair of coronal mass ejections, or CMEs, blasted off the sun and headed toward Earth. A CME is a huge bubble of plasma that's ejected from the sun's corona over the course of several hours. Disturbances of the Earth's magnetic field (geomagnetic storms) and auroras are possible Aug. 23 and Aug. 24 in Alaska, Canada and possibly beyond as a result. The active region can be seen in the lower right corner of the image.

Photo by NASA