HR: 0800h
AN: P11C-0131    [Abstracts]
TI: Water and Hydrocarbon Distributions in Saturn's Upper Atmosphere
AU: Feng, D D
EM: feng@atmo.arizona.edu
AF: Institute of Atmospheric Physics, Univ. Of Arizona, 1118 E. 4th Street, Tucson, AZ 85721 United States
AU: * Ben-Jaffel, L
EM: bjaffel@iap.fr
AF: Institut d'Astrophysique de Paris-CNRS, 98bis Boulevard Arago, Paris, 75014 France
AU: F. Herbert, F L
EM: herbert@vega.lpl.arizona.edu
AF: Lunar and Planetary Laboratory, Univ. Of Arizona, Space Science Building, Tucson, AZ 85721 United States
AU: Herman, B M
EM: herman@atmo.arizona.edu
AF: Institute of Atmospheric Physics, Univ. Of Arizona, 1118 E. 4th Street, Tucson, AZ 85721 United States
AB: We describe a new method for determining atmospheric composition that uses occultation observations and solar reflected spectra to derive self-consistently the abundance of several minor constituents in the upper atmosphere of planets. The data analysis process iterates between matrix inversion of occultation data and radiative transfer calculations of the reflected spectra. Simultaneous analysis of the Voyager 2 Ultraviolet Spectrometer stellar occultation observations obtained during Saturn encounter, and an International Ultraviolet Explorer albedo spectrum of the planet obtained in 1983, respectively, provided the height distributions of eleven minor constituents from the top of the troposphere up to the atmospheric homopause region. These constituents are: CH4, C2H2, C2H4, C4H2, C2H6, H2O, GeH4, PH3, AsH3, CO2, and NH3. Our results seem to be consistent with hydrocarbon abundances recently derived from observations by the Infrared Space Observatory. H2O appears as a key element of the upper atmosphere of Saturn that strongly influences its chemistry and that of the ionosphere. Because of the stratospheric cold trap, an external source for Saturn's stratospheric water may be indicated.
DE: 5704 Atmospheres (0343, 1060)
DE: 5709 Composition (1060)
DE: 6275 Saturn
SC: Planetary Sciences [P]
MN: Fall Meeting 2005