Studies of low-energy plasma motion

This report is divided into two sections. The first describes the results of a comprehensive study of the mid-latitude trough. This is a depletion of ionospheric plasma that can occur at all local times and is due to the convection and diffusion of low energy plasma in latitude regions where magnetic field lines extend many earth radii in the anti-sunward direction. The morphology of the trough is described in terms of local time variations of its width, depth, gradients, and location. The second section of the report describes the design and operation of a new ion sensor experiment package that makes direct measurements of the bulk motion of the low energy plasma. The experiment is an array of planar ion sensors to determine the magnitude and direction of the ion bulk motion as seen from a spin-stabilized satellite. (Author).