In video taken by the NASA STEREO A spacecraft of the north polar region of the sun on Feb. 12, 2009, we see the projection of the faint mass-loading/heating outflows against the darker corona of a "coronal hole," the source of the fast solar wind.

Credit: Scott McIntosh, Bart De Pontieu, Viggo Hansteen and Karel Schrijver/UCAR. Permission granted for non-commercial, non-profit research or educational purposes only. Contact UCAR for permissions regarding additional use.

Back to article