Saturn´s rings: Voyager 1 radio occultation experiment results

The Voyager 1 encounter with Saturn in 1980 included the first radio occultation measurements of the ring system. Opacity of and scattering by Saturn´s rings were measured at 3.6- and 13-cm wavelengths using transmissions from the spacecraft to the Earth. Detailed models of ring structure have been derived from these data at radial resolutions as small as 1 km, depending on the radio opacity of the region probed. Inverse power-law-type distributions of ring particle sites with indices of about 3 and upper size cutoffs near 5 m are in good agreement with the data, but parameters vary throughout the rings. Occultation measurements have also provided information on ring dynamics and have led to a more precise definition of Saturn´s pole vector.