The interaction of the solar plasma with the geomagnetic field

The interaction of a uniform plasma stream in the joint interplanetary and geomagnetic field when there is a magnetic field along the stream lines is considered. The discussion is restricted to two dimensions. It is assumed that in front of the stream and outside the geomagnetic field boundary a shock wave develops as in the case of supersonic flow past blunt-nosed bodies. The magnetic field is found to be proportional to the particle flux density. The magnetohydrodynamic equations in the transition layer between the shock and the body are solved numerically, and the effect of the magnetic field on the stand-off distance of the shock is considered. The body causing the assumed shock is obtained and related to the equatorial cross section of the geomagnetic field boundary.