Plasma Flow in Jupiter's Inner and Middle Magnetosphere

Measurements of the thermal ion component of the plasmas acquired with the Galileo spacecraft at Jupiter are examined for evidence of the patterns of flow existing in the plasma torus and the middle magnetosphere. The observations are of interest because they provide constraints for models addressing transport and circulation of particles and magnetic flux. Plasma transport is believed to be important in development of Jupiter's main ring of auroral luminosity, which has been studied extensively in telescopic observations, and which will be investigated during the Juno mission. Features of interest in the Galileo observations include regions of both outward and inward radial flow. Additionally, there is an apparent decline with radial distance from Jupiter in the component of velocity aligned with corotation, followed by an apparent recovery as distance further increases. In this presentation, these observations are discussed and compared with expectations based on models of magnetospheric circulation, models of the coupling of the ionosphere to the magnetosphere associated with the aurora, and prior observations from the Voyager spacecraft.