Published online by Cambridge University Press: 14 August 2015
Regions of enhanced radio brightness in the polar areas of the Sun were detected in 1974 at the Crimean Astrophysical Observatory of the Academy of Sciences of the U.S.S.R. The effective temperatures of these regions exceeded that of the undisturbed Sun by 1500 K and 2200 K at 8.2 and 13.5 mm wavelengths respectively. Radio brightness distributions of the Sun obtained with the 22-m radio telescope, at 8.2 and 13.5 mm with angular resolutions of 1!6 and 2!55 respectively are shown in Figure 1. Regions of enhanced radio brightness near the North Pole of the Sun are seen, beside the typical s-sources at middle and low latitudes.