The irregular structure of the outer regions of the solar corona

Abstract

The radiation from the radio star in Taurus was recorded on a radio interferometer on occasions when the radiation passed through the outer regions of the solar corona. The recorded intensity was found to decrease rapidly as the radial distance decreased. A series of observations carried out during June 1953 with interferometers of different wave-length and spacing have indicated that the results cannot be explained in terms of absorption, or large-scale refraction effects in the corona. The observations may, however, be accounted for by a scattering mechanism arising from the presence of irregular variations of electron density in the corona. An estimate of the size and electron density of the coronal irregularities is made in the range of distance 5 to 15 R ⦿ . It is suggested that the irregular structure represents an extension of the visible coronal rays.