THE CUSP MAGNETOSHEATH INTERFACE ON MAY 29, 1996 - INTERBALL-1 AND POLAR OBSERVATIONS/

On May 29, 1996, under steady strong northward IMF and high solar wind dynamic pressure conditions both Polar and Interball cross field line s that pass through the northern cusp and apparently close to the post -cusp reconnection site. The magnetopause current observed by Interbal l consists of two quite distinct layers, an inner broad current that i s quite turbulent and another current that is quite abrupt and quiet. Polar also crosses current layers, similar to the Interball inner one. These observations support a model in which cusp field lines experien ce essentially stochastic behavior but on average provide topological connection between the cusp and magnetosheath.