Departure of Long-Wave Solar Radiation from Black-Body Intensity

Abstract

IN some recent experiments of great interest and importance, both Reber¹ and Southworth² have succeeded in detecting and measuring solar radiation in the short-wave end of the radio spectrum. The wave-length employed by Reber was 187 cm., while the three wave-lengths used by Southworth, although not precisely specified, were of the, order of 10 cm. and less. In both series of experiments it was found that the intensity of solar radiation approximately conformed to that emitted by a black body at a temperature of 6,000° K. In another series of experiments of somewhat allied character, Jansky is reported to have been unable to detect solar radiation using a longer wave-length, of 14·6 metres, although his apparatus was sufficiently sensitive to detect the electromagnetic radiation, which he discovered in 1931, coming from the vicinity of the Milky Way.