Photo of the Week for March 20, 2015

The current solar cycle may be gradually winding down from its peak of activity last summer, but that doesn’t mean things have quieted down entirely, as this detailed mosaic by Brian Colville graphically demonstrates. “This was assembled from approximately 10 separate frames, which were required to cover this massive feature which has been estimated to span close to 900,000 kilometres,” Colville says.

Imaging from his observatory in Cambray, Ontario, on February 10, Colville  used a modified 6-inch f/8 Celestron refractor fitted with a 2× Barlow lens and Lunt etalon and blocking filter. The individual images were culled from AVI video files captured with a Point Grey Grasshopper Express CCD camera.