Short periodic exoplanets with a strong magnetosphere may trigger plasma effects on the surface of their host star. The Jovian-class exoplanet which orbits the 90 light-year distant solar-like star HD179949 may have a very strong magnetic moment, because astrophysical observations have revealed a hot spot on the stellar surface. This hot spot surrounds the stellar surface every 3.093 days with the similar period, which the exoplanet needs for one orbit.

Theoretical studies at IWF investigate the physical processes, which may occur on such stellar-planetary relations. These processes may include magnetic reconnection, which can accelerate planetary plasma so that particle beams may hit the stellar surface. Similar plasma phenomena as they are observed in the Jupiter-Io interaction may also occur.