Saturn's immense magnetospheres differ considerably from Earth's.
These magnetospheres are generated in part by a strong planetary
dynamo and by rapid rotation (~10 hour period). However, key differences
lie in the internal sources of plasma (100s kg/s) provided by Io
and Enceladus. Centrifugal stresses acting on the corotating, low-beta
plasma in the inner magnetosphere lead to radial transport of plasma
via a centrifugally-driven flux tube interchange instability. Instead
of cooling on adiabatic expansion, the plasma is observed to be
hotter at larger radial distances. In the outer magnetosphere the
systems are governed by high-beta, centrifugally-confined plasma
sheets. Observations and theories of the dynamics of Jupiter's
and Saturn's magnetosphere will be discussed. In particular, we
will focus on studies involving "viscous" processes (e.g.
Kelvin-Helmholtz instability) at the magnetopause boundary that
facilitate the transport of mass, momentum, and energy from the
solar wind to the magnetosphere.