JOVIAN SYSTEM DATA ANALYSIS PROGRAM PROPOSAL SUMMARY

We propose to analyze data from the four optical remote-sensing instruments on the Galileo Orbiter (NIMS, PPR, SSI and UVS) and the Wide Field/Planetary Camera 2 (WFPC2) on the Hubble Space Telescope to investigate the jovian polar atmosphere (the stratosphere and upper troposphere). Although we will focus on the spatial distribution and microphysical properties of the haze, the primary thrust of our work will be to illuminate processes responsible for the creation of the haze and its evolution and the dynamical nature of the polar stratosphere. A study of the polar haze can tell us much about the role of auroras in creating the haze and the importance and nature of eddies and jets in transporting or confining the polar stratospheric atmosphere. Our own unpublished work with WFPC2 UV images, as well as new results documented by Mark Vincent (Ph.D. thesis, U. of Michigan) point to a dynamically exciting polar stratosphere as revealed by haze morphology. We will use the broad wavelength coverage from less than 200 nm (WFPC-2, UVS) to greater than 3000 nm (WFPC2, PPR, SSI and NIMS) , together with measures of the scattering at high phase angles from Galileo, and linear polarization (PPR) at phase angles near 90 degrees to determine haze particle shape and size distribution. We will use UV and longer-wavelength methane bands to probe vertical structure. High spatial resolution images from the UV to the IR will provide new results on the 3-dimensional structure of the haze, its motion and evolution spanning a 3.5-year period, and its relation to auroral energy deposition. As a major part of this effort we will bring to bear sophisticated theoretical treatments we have developed for particle optical properties (e.g. cluster aggregates), radiative transfer, microphysical, and transport models to interpret the observations