Multiwavelength Radio Observations of Saturn's Rings at Low Inclinations
Dunn, D. E. (U. Iowa), Molnar, L. A. (U. Iowa), Fix, J. D. (U. Iowa)
We present final brightness temperature maps of Saturn as observed at its equinox (20 November 1995) with the Very Large Array at 0.7, 2.0, 3.6, and 6.1 cm wavelength. The ring inclination angle was . The western ansa was brighter than the eastern one at every wavelength, an effect seen by de Pater and Dickel (1991) at higher inclinations. The asymmetry cannot be understood in terms of a single particle scattering phase function which should be mirror symmetric on average. We suggest instead the effect is caused by multiple scattering in an anisotropic particle distribution, such as a gravitational wake.
We also present preliminary brightness temperature maps of Saturn at a second epoch, February 1997, at 1.3, 2.0, 3.6, 6.1, 18, and 20 cm wavelength. The ring inclination angle was . The data at this epoch have a higher sensitivity and finer resolution than the earlier data, in addition to havin a more uniform spatial coverage.