Flows and Obstacles in the Heliosphere

John D. Richardson


The solar wind flows outward from the Sun at supersonic speeds. As it moves outward it encounters a variety of obstacles which affect the flow if different ways: planets, comets, interstellar neutrals, and the interstellar medium. In addition, structures in the solar wind such as ICMEs and corotating streams also alter the plasma flow. This talk describes these interactions and compares and contrasts the effects of these various obstacles on the solar wind. Recent Voyager 2 results on the interaction of the solar wind with the interstellar medium with be highlighted. Sheath regions surrounding these obstacles will be emphasized.