HR: 0800h
AN: P11B-0116    [Abstracts]
TI: Empirical Constraints on the Inventory of Oxidants Produced on the Surface of Europa
AU: Carlson, R W
EM: tassie@earthlink.net
AF: NASA Jet Propulsion Laboratory/Caltech, 4500 Oak Groove Drive, Pasadena, CA 91101 United States
AU: * Hand, K P
EM: khand@stanford.edu
AF: Dept. Geological and Environmental Sciences, Stanford University, 450 Serra Mall, Bldg 320, Stanford, CA 94305 United States
AB: The surface ice of Europa is radiolytically modified by high-energy electrons and ions and photolytically by solar ultraviolet photons. Observations from the Galileo Near Infrared Mapping Spectrometer (NIMS), ground-based telescopes, and space telescopes, combined with laboratory experiments, indicate that the production of oxidants, such as H2O2, O2, CO2, and SO2, is a consequence of the surface radiolytic chemistry. Here we present results from work aimed at quantifying the low and high end limits for the surface abundance of each of the oxidants mentioned above. We find that at a minimum, the combination of O2+CO2+SO2 (1.3%+0.08%+0.3%) will yield a low end oxidant contamination of 1.7% by number relative to water. If the CO2 abundance is similar to that of SO2, this number rises to 1.9%. Taking our high end, but still empirically supported, estimate for O2 (4.7%) yields an oxidant contamination of 5.1%. Considering model results for upper limits on CO2 and SO2 yields total oxidant contamination of 7.6% by number relative to water. Thus our predicted range for radiolytically produced oxidant contamination of the surface ice is 1.7-7.6% by number relative to H2O.
DE: 0726 Ice sheets
DE: 6020 Ices
DE: 6218 Jovian satellites
DE: 6221 Europa
SC: Planetary Sciences [P]
MN: Fall Meeting 2005