2011A&A...532A..21M

We investigate the electromagnetic interaction of a relativistic stellar wind with a planet or a smaller body in orbit around the star. This may be relevant to objects orbiting a pulsar that are expected to hold a planetary system, such as PSR B1257+12 and PSR B1620-26, or to pulsars with suspected asteroids or comets. We extend the theory of Alfven wings to relativistic winds. When the wind is relativistic but slower than the total Alfven speed, a system of electric currents carried by a stationary Alfvenic structure is driven by the planet or by its surroundings. For an Earth-like planet around a ``standard'' second pulsar, the associated current can reach the same magnitude as the Goldreich-Julian current that powers the pulsar's magnetosphere.