A Giant Coronal Hole

A large coronal hole in the sun's southern hemisphere is currently directing high-speed solar wind toward Earth, increasing the likelihood of minor G1-class geomagnetic storms from May 19-21 as our planet passes through this stream. These coronal holes, which appear dark in extreme ultraviolet images due to missing hot gas, are regions where magnetic fields open, allowing solar wind to escape. This particular hole, about a million kilometers wide, has been recurring roughly every 28 days since February, and its associated solar wind has previously caused notable auroras, such as those seen across northern US states in March.