HR: 16:15h
AN: P44A-02    [Abstracts]
TI: Cassini UVIS Observations of Saturn H$_{2}$ Dayglow Emission
AU: * Hallett, J T
EM: jtew@usc.edu
AF: University of Southern California, Aerospace and Mechanical Engineering Department Mail Stop RRB-1191 854 W. 36th Place, Los Angeles, CA 90089-1191 United States
AU: Shemansky, D E
EM: dons@hippolyta.usc.edu
AF: University of Southern California, Aerospace and Mechanical Engineering Department Mail Stop RRB-1191 854 W. 36th Place, Los Angeles, CA 90089-1191 United States
AU: Liu, X
EM: xianming@usc.edu
AF: University of Southern California, Aerospace and Mechanical Engineering Department Mail Stop RRB-1191 854 W. 36th Place, Los Angeles, CA 90089-1191 United States
AU: Cassini UVIS Team, T
EM: Laura.Bloom@lasp.colorado.edu
AF: University of Colorado, Laboratory for Atmospheric and Space Physics, 1234 Innovation Drive, Boulder, CO 80303-7814 United States
AU: Cassini UVIS Team, T
EM: Laura.Bloom@lasp.colorado.edu
AF: Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA 91109-8099 United States
AU: Cassini UVIS Team, T
EM: Laura.Bloom@lasp.colorado.edu
AF: California Institute of Technology, Division of Geological and Planetary Sciences 1200 E. California Blvd. , Pasadena, CA 91125 United States
AU: Cassini UVIS Team, T
EM: Laura.Bloom@lasp.colorado.edu
AF: Max-Planck-Institut, Max-Planck-Strasse 2 D-37191 Katlenburg, Lindau, 37191 Germany
AU: Cassini UVIS Team, T
EM: Laura.Bloom@lasp.colorado.edu
AF: Institute for Photogrammetry, Stuttgart University Geschwister-Scholl-Strasse 24-D, Stuttgart, 70174 Germany
AB: An analysis of the Cassini UVIS Saturn H$_{2}$ Lyman and Werner band emission is presented. The spectrum was obtained during the Cassini pre-SOI period by binning multiple Saturn observations from April 2, 2004 to May 12, 2004. The H$_{2}$ dayglow emission is concentrated near the sub-solar point at a latitude of approximately -21 degrees. The H$_{2}$ emission is examined for both the EUV and FUV instruments, covering a total spectral range of $\sim$(561 to 1900) $\AA$. The H$_{2}$ emission is modeled using fine-structure, hydrogen physical chemistry. The relative contributions of solar and low energy electron excitation in the observed emission are analyzed with the fine-structure chemistry model. H$_{2}$ solar resonance scattering is more prevalent in the Saturn dayglow spectrum than the Jupiter dayglow spectrum obtained by Cassini UVIS in December of 2000. Details of non-LTE H$_{2}$ ($v$ : $J$) partitioning and altitude range of excitation predicted from the hydrogen chemistry model are discussed. The source processes and altitude inferred from the spectrum have important implications for the examination of the Saturn thermospheric heating mechanism.
DE: 5704 Atmospheres--composition and chemistry
DE: 6275 Saturn
SC: Planetary Sciences [P]
MN: 2004 AGU Fall Meeting