Speaker
Description
Key aspect of moon-magnetosphere interactions are dependent on the diversion of the flow around the conducting body of the moon and the acceleration of the flow along the flanks of the moon. Analytic solutions for the magnetic field perturbations [Neubauer, 1980; Saur et al., 2004 and references therein] have been derived assuming the moon’s conductance is constant within a specified radius and zero outside that radius. Solutions also exist [Simon, 2015] for a conductivity which varies as a power law of the radius. Simon, 2015, applied this solution to analysis of Cassini magnetometer data from Enceladus encounters. But these solutions can be used to calculate the flow field as well. Numerical models can also be used to calculate the flow field, but they are sensitive to boundary condition applied at the surface of the moon and may have limited fidelity within a fraction of a body radius. Numerical models are also computationally expensive, and often impractical to run for a wide variety of parameters. Here we present an analytic solution similar to those of Simon et al., but for an exponential conductivity profile which is more applicable to the ionospheres of moons like Io and Europa. We then describe the effects the resulting of flow field would have on the interaction between the moon’s ionosphere and the plasma, the production of charge exchange ions and the energy the resulting fast neutral atoms.
