Electric current systems at Mars and Venus

The physics of the interaction of unmagnetized planets with the Solar wind hasbeen investigated since the first Mariner spacecraft did reach Mars and Venusmore than 50 years ago. Recent observations of the magnetic fields at Mars allowed to derive the global electric current configuration in the Martian system.Earlier magneto hydro-dynamic models were able to predict the formationand location of the bowshock in front of the planets. More sophisticated models of the interaction with the magnetized solar wind later could demonstratethe global static picture of the plasma environment of Mars and Venus. But earlier models were rarelyable to model dynamic effects and the timing of physical process in this interaction.We here use the open source PLUTO code in its 3D spherical hydrodynamic and magneto-hydrodynamic version. We also develop a multi-species extension of this code. We investigate the interaction of the solar wind with the ionospheres of Mars and Venus with the aim to understand the importance of different physical effects on bow shock location, ion escape and specifically the electric current structures. We compare these simulations to observations by the VEX and MAVEN spacecraft.