Cosmic Radio Noise as Measured in the Satellite Ariel II: Part II. Analysis of the Observed Sky Brightness

Abstract

The various sources of cosmic radio emission which may contribute to the radio brightness of the sky at frequencies near 1 Mc/s are evaluated, and compared with the experimental values, including the first results from the receiver in the satellite Ariel II. The expected average brightness corresponds well with the measured value betewen 2 Mc/s and 3 Mc/s, but the spectrum is flatter than expected in this region. It is shown (i) that at frequencies below about 5 Mc/s most of the radiation is of extragalactic origin, and (ii) that the low values of brightness below 2 Mc/s are probably due to absorption in ionized hydrogen.