Origin of Radio Emissions from the Disturbed Sun

Abstract

IN a recent communication¹ it was pointed out that thermal radiation from the solar corona should be detectable at wave-lengths as long as one or two metres. This source cannot account, however, for the much stronger emissions which are correlated with sunspots^2,3,4. It has been shown^5,6 that the latter emissions probably come from the immediate vicinity of active sunspots, and would require impossibly high source temperatures of about 10⁹ degrees for explanation in terms of thermal radiation.