JOVIAN SYSTEM DATA ANALYSIS PROGRAM PROPOSAL SUMMARY

The Galileo UV observations provide detailed information on the Jupiter aurora because of the diagnostic information contained in the unprecedented broad spectral coverage. The Galileo Ultraviolet Spectrometer (UVS) and Extreme Ultraviolet Spectrometer (EUVS) performed the first near-simultaneous observations of the Jupiter aurora in three wavelength regions: Extreme Ultraviolet (EUV) (540-1200 Å), Far Ultraviolet (FUV) (1200-1700 Å) and Middle Ultraviolet (MUV) (1700-3200 Å) and provide basic information on auroral processes and structure. The objectives of the proposal are: 1) to perform morphological studies in the UV of the Jupiter aurora over the two year standard mission (System III, latitude (north and south) and local time), 2) to model the 100 near-simultaneous EUV, FUV and MUV observations of the Jupiter aurora by the UVS and EUVS with a combined state-of-the-art UV auroral H2 spectral code and electron transport two-stream code for determination of composition, altitude structure, energetics and particle identity (ion or electron) 3) to identify probable hydrocarbon absorbers affecting UV emission, 4) to compare Solid State Imaging (SSI), Near Infrared Mapping Spectrometer (NIMS), Hubble Space Telescope (HST) and Fields and Particles (F & P) campaign data obtained in auroral feature track, full rotation and TransAuroral Region (TAR) observations and (5) to deduce Eo, the characteristic energy, for the incident electron (ion) spectrum and Q, the spectrum energy flux in ergs/cm2/s and to compare to the F & P electron (ion) distribution function on the same field lines in the middle magnetosphere 12-30 RJ. Most of the Jupiter UV auroral observations occurred near the pre-dawn terminator - a vastly different local time than Hubble Space Telescope (HST) and International Ultraviolet Explorer (IUE) observations, which should allow the separation of local time and system III effects. A subset of the data, acquired during campaigns with Hubble Space Telescope (HST), Near Infrared Mapping Spectrometer (NIMS) and Galileo Solid State Imaging (SSI), provide extended spectral information and high resolution spatial imaging about the morphology, chemistry of the aurora and total energy output of the aurora in the UV, visible and infrared. The FUV spectrum is sensitive to the abundance of CH4 and C2H2 absorbers; while the EUV spectrum is sensitive to the abundance and temperature of H2 from self-absorption and the abundance of hydrocarbon absorbers. The MUV spectrum, observed for the first time in astronomy, is diagnostic of the relative importance and distribution of low energy secondary electrons in the aurora. The MUV spectrum is produced by the optically forbidden excitation of the H2 a-b continuum while the FUV spectrum is formed by the dipole allowed excitation of the Lyman and Werner band systems. Analysis of the simultaneous EUV/FUV/MUV spectral observations will yield the primary and secondary electron distributions, the CH4 and C2H2 column densities and total energy deposited into the aurora. There is no accurate auroral model of the vertical structure of the aurora. To gain knowledge of the vertical distribution of the auroral atmosphere we use a two-stream electron transport model coupled with a one dimensional atmospheric heat conduction model to invert the Galileo UV spectral information.