[Previous] | [Session 53P] | [Next]
J. A. Linker (Science Applications International Corporation), M. A. McGrath (Space Telescope Science Institute)
UV (ultraviolet) emissions from atomic sulfur and oxygen provide one of the few direct observations of some of the major constituents of Io's atmosphere. Recent observations from the Hubble Space Telescope have shown detailed structure in UV emissions from neutral species near Io. These neutral emissions are primarily excited by electrons in the Io torus plasma impacting the neutrals. Data from the Galileo spacecraft's encounter with Io have shown that the properties of the Io torus plasma change dramatically near Io as a result of the interaction between Io and the surrounding plasma.
To assess the importance of the the interaction between Io and the plasma torus in producing the morphology of the observed emissions, we have used magnetohydrodynamic (MHD) simulations of the interaction to model the local plasma properties. Using the plasma parameters derived from these models, we develop simulated UV emission images for specific viewing geometries and compare them with actual observations. We have found that the models can reproduce important properties of UV emissions observed in HST STIS images. The implications of our results for understanding the morphology of Io's neutral emissions will be discussed.
The author(s) of this abstract have provided an email address for comments about the abstract: linker@iris023.saic.com