The aurora oval

The aurora oval

. The POLAR spacecraft looks down on an aurora from high above the Earth's north polar region in February 2000, showing the northern lights in their entirety. The glowing oval is 4.5 million meters across. The most intense aurora activity appears in bright red or yellow. The Earth's aurora is typically initiated by magnetic reconnection events in the Earth's magnetotail (Fig. 3.14), on the night side of the Earth. (Courtesy of the University of Iowa and NASA.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University