Configuration of the Jovian magnetosphere

We present a model in which the Jovian magnetosphere is severely inflated by the centrifugal stress of partially-corotating plasma streaming out along field lines from the ionosphere. The model is consistent with observations reported from the Pioneer 10 encounter, including the disc-like field configuration, the diurnal modulation of trapped-particle fluxes, and the inferred departure from rigid corotation in the outer magnetosphere. The field configuration is closed on the dayside, but on the night side the plasma can force the magnetic field open to form a planetary wind flowing in the antisolar direction.