A GLOBAL MAGNETOHYDRODYNAMIC SIMULATION OF THE JOVIAN MAGNETOSPHERE

We have developed a three-dimensional global magnetohydrodynamic simul ation of the interaction between the solar wind and a rapidly rotating magnetosphere and applied it to Jupiter. For fixed solar wind dynamic pressure the rotating model Jovian magnetosphere extends farther towa rd the Sun and has greater extent in the east-west direction than a mo del without rotation but is little different in the north south direct ion,There is a pronounced dawn-dusk asymmetry with the dawn magnetopau se displaced farther from Jupiter. The middle Jovian magnetosphere con tains a thin plasma sheet dominated by rotating plasmas, On the daysid e this plasma sheet thickens near the magnetopause, Near the dawnside magnetopause where rotating Jovian convection is opposed to the solar wind induced flow, a pressure ridge forms where the magnetospheric flo w slows and forms a stagnation region. In the magnetotail the rotating flow is diverted tailward. For x < -100R(J) x-type and o-type neutral lines form. When the solar wind pressure was decreased, the boundarie s moved away from Jupiter and the dayside field lines became stretched into a more tail-like configuration. A flow vortex formed in the even ing middle magnetosphere.