HR: 1340h
AN: P23A-0238    [Abstracts]
TI: Meteoric Ions in Venus' Atmosphere
AU: * Pesnell, W D
EM: pesnell@gsfc.nasa.gov
AF: Nomad Research, Inc., P. O. Box 796, Arnold, MD 21012 United States
AU: Grebowsky, J
EM: Joseph.Grebowsky@gsfc.nasa.gov
AF: NASA/Goddard Space Flight Center, Code 695, Greenbelt, MD 20771 United States
AU: Webb, P A
EM: Phillip.Webb@gsfc.nasa.gov
AF: Nomad Research, Inc., Code 690.1 NASA/Goddard Space Flight Center, Greenbelt, MD 20771 United States
AB: From a thorough modeling of the altitude profile of meteoric ionization in the cytherean atmosphere we have deduced that layers of magnesium, iron, and sodium ions should exist between altitudes between 115 and 120~km. Based on the estimated meteoroid mass flux density, a peak ion density of several $10^3$ ions cm${}^{-3}$ is predicted. Allowing for the uncertainties in all of the model parameters, this value is probably within an order of magnitude of the correct density. The peak density is most sensitive to the meteoroid mass flux density, which determines the source function for Mg from the ablating meteoroids, the eddy viscosity coefficient, which determines the effectiveness of mixing the meteoric input downwards, and the presence of sulfuric acid droplets, which is an efficient sink of metallic compunds. We examine the effect of the aerosol layers in the upper mesosphere of Venus' atmosphere on the metallic layers.
DE: 6207 Comparative planetology
DE: 6295 Venus
DE: 2419 Ion chemistry and composition (0335)
DE: 2427 Ionosphere/atmosphere interactions (0335)
SC: Planetary Sciences [P]
MN: 2004 AGU Fall Meeting