JOVIAN SYSTEM DATA ANALYSIS PROGRAM PROPOSAL SUMMARY

GENERAL OBJECTIVES Analyze Galileo Orbiter and Probe data to improve models of Jovian satellite interiors and Jupiter's atmosphere. GENERAL APPROACH Analysis of Galileo Orbiter gravity, magnetic field, and imaging data of the satellites. Theoretical modelling of internal structure, thermal evolution, and interior dynamics to elucidate the significance of the data. Analysis of Galileo Probe atmospheric structure data to identify gravity waves in Jupiter's atmosphere. Theoretical modelling to study the heating of the Jovian upper atmosphere by upward propagating gravity waves. SIGNIFICANCE The proposed studies will use data obtained by the Galileo Orbiter and Probe to improve our understanding of the Galilean satellites and the atmosphere of Jupiter. PROPOSED RESEARCH Analyze radio Doppler data from 4 flybys of Ganymede during the Galileo mission to determine the gravitational field of the satellite through spherical harmonic degree 4. Use the degree 2 field to derive interior models of Ganymede and the higher degree gravitational coefficients to yield information on gravity anomalies in the regions of closest approach to Ganymede. Explore geophysical models of density and topography anomalies on the rock-ice interface within Ganymede to understand the gravity anomalies and determine the thickness of Ganymede's outer ice shell. Carry out a synthesis of gravity, magnetic field, and imaging data from the Galileo Orbiter mission to better understand the thermal-dynamical evolution of the Galilean satellite system. Develop coupled thermal-dynamical evolution models of the satellites to facilitate the synthesis. Analyze atmospheric structure data from the Galileo Probe. Identify gravity waves in the data and determine their characteristics. Use a full-wave model to study gravity wave propagation into Jupiter's upper atmosphere and determine the contribution of gravity waves to heating the upper atmosphere.