Solar wind interaction with the magnetized interstellar medium Shock - capturing modeling

The interaction between the stellar wind, including the solar wind, and the interstellar medium is the subject of thorough investigation in the latest years. This is due to the possibility of comparison of the physical models for such interaction with the measurements performed by Voyager, Pioneer, and Ulysses spacecrafts. The presence of the magnetic field necessitates the solution of the magnetohydrodynamic (MHD) equations for proper analysis of the obtained data. We present here a simple numerical approach for the modeling of the stellar wind interaction with the magnetized interstellar plasma. It is based on the second-order of accuracy high-resolution numerical scheme which gives a drastic simplification of the numerical algorithm comparing with the methods based on the exact characteristic splitting of the Jacobian matrices. New nonreflecting boundary conditions for subsonic outer boundaries at the far-field are presented, which are suitable for MHD calculations. A simple numerical approach is used to satisfy the magnetic field divergence-free condition in the computational region. The method is applied to the analysis of the solar wind – interstel-lar medium interaction for various values of the magnetic field strength and the influence of the latter is studied on the size of the heliopause and on the termination and the bow shock stand-off distance.