Planetary bow shocks: Asymptotic MHD Mach cones

Abstract

A direct approach for determining the asymptotic MHD Mach cone is formulated and solved. An implicit analytical solution enables the calculation of the asymptotic downstream slope of MHD Mach cones at any clock angle for arbitrary Ms, Ma, and bu. The solution obtained includes all previously known symmetric cases. The elongation and shift of the asymptotic fast mode shock cross-section are studied for a wide range of upstream plasma parameters as well as its unusual 'chopped' shape under certain conditions. Our results may be useful for planetary shock modeling and MHD numerical codes verification. Copyright © The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences.