JOVIAN SYSTEM DATA ANALYSIS PROGRAM PROPOSAL SUMMARY

Archived radio doppler data from four encounters of the Galileo spacecraft with Ganymede will be collected together and analyzed. Second, third, and fourth degree gravitational harmonics will be determined. The second degree harmonics will be used to obtain a suite of possible interior models, while the third and fourth degree harmonics will yield information on gravity anomalies in the regions of closest approach to Ganymede. Once identified by this higher-harmonic approach, the gravity anomalies will be represented both by a distribution of mass points and by finite disks at the ice-rock interface.