A New Model for Turbulent Heating of Jupiter’s Magnetosphere

Abstract:

The ion temperature of the magnetosphere of Jupiter derived from Galileo PLS data was observed to increase by about an order of magnitude from 10 to 40 Jupiter radii. This suggests presence of heating sources that counteract adiabatic cooling effect of expanding plasma. There have been different models trying to explain such observation using different heating mechanisms, including a heating model based on magnetohydrodynamic (MHD) turbulence [Saur, Astrophys. J. Lett., 602, L137, 2004]. We revisit that model, which is based on flux tube diffusion, and find that it is not adequate in explaining the heating. To account for possible heating by turbulence, we apply another turbulence heating model based on convection, which is commonly used in modeling solar wind heating. Based on analysis of Galileo magnetometer data, we find that observed MHD turbulence could potentially provide the required heating based on this model.

This work is supported by a NASA grant (NNX14AM27G).