Jupiter's ring system revisited: A deeper understanding from Galileo visible and infrared observations

Despite its crippled high-gain antenna, the Galileo mission to Jupiter provided a wealth of information on the Jovian system. Its atmosphere, satellite system, magnetosphere and rings were scrutinized to a degree that will not be possible until another spacecraft mission is sent to Jupiter. I have analyzed data from Galileo's Solid State Imaging experiment (SSI) and Near Infrared Mapping Spectrometer (NIMS) to characterize the rings, model the particle size distribution of Jupiter's main ring and to constrain the relevant physical processes. A clearer picture of this unique ring system is starting to develop.; By analyzing how the main ring's brightness varies with observation wave-length and viewing geometry, I have extended the size distribution of the dusty main ring to include larger particles than could be constrained by the Voyager data. I have found that there are fewer dust grains in the main ring larger than 15 μm than the size distribution determined by Showalter et al. (1987) would suggest. This implies that the process or processes that drive the evolution of ring particles smaller than 15 μm differs from those of larger ring particles.; I have also studied some of the ring's more peculiar features. The near arm/far arm asymmetry reported on by Jewitt and Danielson (1981) and Showalter et al. (1987) has not yet been definitively explained, but my analysis suggests that it is the result of stochastic, time-variable processes acting upon the main ring. The Metis notch, which appears in Voyager and Galileo images, is a feature that also continues to defy explanation. However, my preliminary attempts to understand the origin of this feature suggest that ring particles may be interacting with tiny Metis in a fashion that is reminiscent of planetesimals interacting with planets accreting in the proto-solar nebula. In this regard, it is possible that Metis and the Metis notch represent a present-day analog for processes that relate to planetary formation.