MHD effects of the solar wind flow around planets

The study of the interaction of the solar wind with magnetized and unmagnet ized planets forms a central topic of space research. Focussing on planetar y magnetosheaths, we review some major developments in this field. Magnetos heath structures depend crucially on the orientation of the interplanetary magnetic field, the solar wind Alfven Mach number, the shape of the obstacl e (axisymmetric/non-axisymmetric, etc.), the boundary conditions at the mag netopause (low/high magnetic shear), and the degree of thermal anisotropy o f the plasma. We illustrate the cases of Earth, Jupiter and Venus. The terr estrial magnetosphere is axisymmetric and has been probed in situ by many s pacecraft. Jupiter's magnetosphere is highly non-axisymmetric. Furthermore, we study magnetohydrodynamic effects in the Venus magnetosheath.