Electrons in ionosphere catch a plasma wave to produce brightest auroras

Enlarge / Physicists report definitive evidence that auroras that light up the sky in the high latitudes are caused by electrons accelerated by a powerful electromagnetic force called Alfvén waves. (credit: Austin Montelius, University of Iowa) In August and September 1859, there was a major geomagnetic storm—aka, the Carrington Event, the largest ever recorded—that produced […]