Flows and obstacles in the solar wind

Understanding the physics of the various disturbances in the solar wind is critical to successful forecasts of space weather. The STEREO mission promises to bring us new and deeper understanding of these disturbances. As we stand on the threshold of the first results from this mission, it is appropriate to review what we know about solar wind disturbances. Because of their complementary nature we discuss both the disturbances that arise within the solar wind due to the stream structure and coronal mass ejecta and the disturbances that arise when the solar wind collides with planetary obstacles, such as magnetospheres.