HR: 0800h
AN: P31A-0958    [Abstracts]
TI: Tethys: Modeling of Near Infrared Telescopic Observations
AU: * Dalton, J B
EM: dalton@mail.arc.nasa.gov
AF: SETI Institute, 515 N. Whisman Road, Mountain View, CA 94043 United States
AU: * Dalton, J B
EM: dalton@mail.arc.nasa.gov
AF: NASA Ames Research Center, MS 245-3, Moffett Field, CA 94035 United States
AU: Roush, T L
EM: ted.l.roush@mail.arc.nasa.gov
AF: NASA Ames Research Center, MS 245-3, Moffett Field, CA 94035 United States
AU: Emery, J
EM: jemery@mail.arc.nasa.gov
AF: NASA Ames Research Center, MS 245-3, Moffett Field, CA 94035 United States
AU: Cruikshank, D
EM: dale.p.cruikshank@mail.arc.nasa.gov
AF: NASA Ames Research Center, MS 245-3, Moffett Field, CA 94035 United States
AB: We have analyzed near-infrared telescopic spectral observations of Tethys for comparison to Cassini observations. A mixture modeling code based on Hapke theory (Hapke, 1981, 1993) has been adapted and combined with an iterative simplex algorithm (Press et al., 1992; Bauer et al., 1998) and applied to observations of Tethys. The mnodel can treat spectra as nonlinear mixtures of various grain sizes and compositions, as linear mixtures of adjacent spatial regions, or a coimbination of both. We have assembled from various sources (Ockman, 1957; Warren, 1984; Hudgins et al., 1993; Grundy and Schmitt, 1998) water ice optical constants for the near-infrared spectral range for temperatures of 70, 80, 90, and 100 K. Preliminary results indicate that telescopic spectra of Tethys are best matched by crystalline water ice with a range of grain sizes, with a small complement of dark material such as amorphous carbon.
DE: 6061 Remote sensing
DE: 6280 Saturnian satellites
SC: Planetary Sciences [P]
MN: 2004 AGU Fall Meeting