The Distribution of Dust in Interplanetary Space

The paper presents a model of the distribution of interplanetary dust based upon brightness and polarization measures of the zodiacal light, brightness and polarization measures of the F -component of the solar corona and the distribution function of particle radius obtained from measurements using space vehicles. The model differs from previous ones in that it shows that the density increases with increasing distance from the Sun as far as 100- |$R_\odot$| but it does not explain the observed infra-red excess. It is then shown that agreement with observation is improved and the calculated infra-red excess is increased if it is supposed that the albedo of the particles increases with increasing distance from the Sun.