Massive Coronal Hole A coronal hole, stretching across the top half of the Sun, rotated into a position where it was facing Earth (Feb. 1 -3, 2011). Coronal holes are magnetically open regions on the Sun that stream high-speed solar wind into space. In these images taken by SDO in extreme ultraviolet light, the unevenly shaped hole appears quite dark. As the coronal hole passed the meridian line, the path of its streaming particles began to be aimed at Earth. There should be a good chance for aurora sightings beginning Feb. 4.