Investigation of the Influence of the Solar-Cycle Activity on the Gasdynamic Structure of the Heliosphere

The interaction of the unsteady solar wind with the interstellar plasma has been simulated on the basis of the conservative TVD numerical method of the second order accuracy both in space and time. The influence of the 11-year solar cycle on the gasdynamic structure of the heliospheric interface has been investigated. It is shown that the average density and pressure in the region of compressed interstellar wind are less than the corresponding values of the stationary flow. This phenomenon can significantly influence the penetration of neutral H-atoms into the solar system. It is shown that the average velocity of the periodic termination shock motion is of the same order or greater than the velocity of spacecraft 'Voyager'.