A universal phase function for Jovian clouds from the visible to near-IR wavelength region. I. Zone phase function

A set of wavelength-dependent scattering phase functions for Jupiter's clou ds has been obtained; the Mie theory was employed to simulate well-defined scattering phase functions deduced from an analysis of the Pioneer 10 photo metry data (Tomasko et al. 1978, AAA 021.099.011). A reasonable fit to the cloud-phase functions for the bright zone (STrZ) was obtained with a partic le effective radius, r(eff), of 0.96 mu m and the real part of the refracti ve index, n(r), being 1.591 for the blue and 1.535 for the red, slightly hi gher than the nominal values for ammonia ice. The derived Mie phase functio ns were tested against several STrZ data. The appropriateness of these phas e functions has been demonstrated through the fact that they reproduce not only the observed limb-to-limb intensity profiles, but also the correct wav elength dependence of the haze optical thickness for a wide wavelength rang e from visible to near-infrared.