The heliopause

Publisher Website
Google Scholar
Abstract
There is a growing anticipation among space scientists that a Pioneer or Voyager spacecraft will soon pass through one of the last major frontiers in the solar system—the heliospheric terminal shock. Some unknown, but perhaps small, distance beyond the terminal shock is the heliopause, marking the final boundary between solar wind and galactic plasmas and the final goal of these spacecraft. This occasion is drawing widespread attention because of the opportunity it offers to obtain a wealth of information on the properties of the galaxy, the interstellar medium, and the large‐scale interactions of that medium with stellar winds. The anticipation has been raised by several tentative remote detections of the shock placing it just beyond the present spacecraft locations. However, uncertainties in the physical processes and parameters that determine the location of the boundary lead to equal uncertainties in predicting which of the spacecraft will reach it first. This review is largely phenomenological with the intent of providing an overview of the topic and the dominant physical processes.
Keywords