Three-dimensional multi-fluid simulations of Pluto's magnetosphere: A comparison to 3D hybrid simulations

Results from 3D multi-fluid simulations of the solar wind interaction with Pluto are compared to 3D hybrid simulations of the same interaction. The results from the multi-fluid simulations are similar to the hybrid results in both the overall size of the magnetosphere as well as predicting pick-up of ionospheric ions by the solar wind. The results from the multi-fluid simulations also show how an increase in the mass of the pick-up ion leads to a larger pick-up region and an asymmetric bow shock. When the solar wind speed is doubled, but its dynamic pressure is held constant, the size of the magnetosphere more than doubles and the asymmetry of the bow shock and pick up region are enhanced. This effect is not present in MHD simulations since ion cyclotron effects are neglected. The results illustrate the ability of the multi-fluid technique to capture ion cyclotron effects, like the hybrid technique.