Scattering in the Earth's Atmosphere: Calculations for Milky Way and Zodiacal Light as Extended Sources

Summary. We present the results of detailed calculations on first order Rayleigh- and Mie-scattering in the Earth's atmosphere illuminated by the Milky Way and the Zodiacal Light. We discuss the influence of various independent parameters, as optical depth of the Rayleigh- and Mie-component and position of Milky Way and Zodiacal Light Linear and circular polarization of the scattered light are considered. The results are compared with the work already done in this area and with the procedures commonly applied in reducing photo- metric observations of extended sources of the night sky. It is shown that a substantial part of the discrepan cies between the brightness distributions of Zodiacal Light resp. Milky Way given by different authors is due to an inaccurate treatment of the atmospheric scattered light. Key words: scattering polarization - night sk luminosity - photometry of Zodiacal Light and Milky Way