PROFESSOR CARRINGTON, CALL YOUR OFFICE: “FLARES ON THE HORIZON: The northeastern limb of the sun is surging with flares–a sign that old sunspot AR2936 (described below) is about to return. NASA’s Solar Dynamics Observatory recorded this C5-class explosion during the early hours of Feb. 20th. The flare was stronger than it appeared. It was partially eclipsed by the edge of the sun. Unobstructed, the explosion was probably M-class. The underlying sunspot will soon emerge into view, potentially exposing Earth to a source of strong flares.”