Possible detection of a ring system in Saturn's magnetosphere

Abstract

The region of the magnetosphere of Saturn around 14 radii and 19 radii has been of special interest since the detection of anamolous dips in the low-energy plasma ion-density in these regions by the Voyager 1, Voyager 2 and Pioneer 11 spacecrafts. Lazarus et al. suggested that these density dips may be due to long-lived particulate or gaseous structures in the equatorial plane of Saturn¹. Baron and Elliot, using the charge-coupled device (CCD) imaging technique, found no evidence of any material existing between 10 and 36 Saturn radii². Their negative results, however, have set an upper limit on the extent of a possible material cloud with several assumptions regarding its nature and density. We have observed the occultation of the star SAO158913 from two stations in India following predictions by Mink³. This star showed symmetric dips in the light curves on 24 March 1984 (immersion event) and on 25 March 1984 (emersion event), suggesting the possible presence of particulate matter.