  The hybrid kinetic model supports comprehensive simulation of the interaction
between different spatial and energetic elements of the Europa
moon-magnetosphere system with respect a to variable upstream magnetic field
and flux or density distributions of plasma and energetic ions, electrons, and
neutral atoms. This capability is critical for improving the interpretation of
the existing Europa flyby measurements from the Galileo Orbiter mission, and
for planning flyby and orbital measurements (including the surface and
atmospheric compositions) for future missions. The simulations are based on
recent models of the atmosphere of Europa (Cassidy et al., 2007; Shematovich et
al., 2005). In contrast to previous approaches with MHD simulations, the hybrid
model allows us to fully take into account the finite gyroradius effect and
electron pressure, and to correctly estimate the ion velocity distribution and
the fluxes along the magnetic field (assuming an initial Maxwellian velocity
distribution for upstream background ions). In this paper we discuss two tasks:
(1) the plasma wake structure dependence on the parameters of the upstream
plasma and Europa's atmosphere (model I, cases (a) and (b) with a homogeneous
Jovian magnetosphere field, an inductive magnetic dipole and high oceanic shell
conductivity); and (2) estimation of the possible effect of an induced magnetic
field arising from oceanic shell conductivity. This effect was estimated based
on the difference between the observed and modeled magnetic fields (model II,
case (c) with an inhomogeneous Jovian magnetosphere field, an inductive
magnetic dipole and low oceanic shell conductivity).
