A self‐consistent gasdynamic model of the solar wind interaction with the local interstellar medium (LISM), which took into account the mutual influence of the plasma component (electrons and protons) of the LISM and the LISM H atoms that penetrate into the heliosphere was constructed by Baranov et al. (1981) in the approximation of axial symmetry. This model, however, had a number of defects. In particular, the motion of the H atoms was described by hydrodynamical equations, although the mean free path of the H atoms and the characteristic length of the problem were comparable. An iterative method, that used a Monte Carlo simulation of H atom motion in the field of the plasma component hydrodynamic parameters, was suggested by Baranov et al. (1991) and only the first step of the iteration was realized (non‐self‐consistent problem solution). In this paper the results of the self‐consistent problem solution for a single set of the undisturbed solar wind and LISM parameters are presented. The structure of the upwind as well as wake regions of the flow is calculated. The geometrical pattern of the flow (bow shock, heliopause, termination shock, Mach disc, etc), the bulk velocity and the number densities of H atoms and plasma component are obtained and analyzed as a function of the distance from the Sun for different values of the polar angle. The effects of resonance charge exchange of the LISM H atoms as well as energetic H atoms “born” in the solar wind are taken into account. It is interesting to note that the effect of H atoms penetrating the solar wind results in the disappearance of the complicated flow structure as well as the supersonic regions between the heliopause and termination shock in the downwind region. In future we are going to compare our theoretical results with the results of Voyager 1/2, Pioneer 10/11, Ulysses spacecraft, and other experiments.

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The paper investigates the influence of the local interstellar medium (LISM) proton number density on the gasdynamics of LISM / solar wind interaction. It uses the self‐consistent axisymmetric model of Baranov and Malama (1993) for a constant value of the LISM neutral hydrogen number density (nH∞ = 0.14 cm−3). It is shown that the flow structure is asymmetric relative to the upwind and downwind directions. Numerical results are presented for four values of the proton number density in the LISM: np∞ = 0.005; 0.025; 0.1 and 0.28 cm−3. The results are given along the axis of symmetry only (in upwind and downwind directions). Velocity, number density, and temperature distributions of the plasma component as well as of the H atoms of the LISM are presented. It is shown that the influence of H atoms, penetrating from the LISM into the solar system on the solar wind may be strong enough to be observed by the “Voyager” spacecraft. The results show that the number density of the LISM's plasma component as well as of the solar wind has very large gradients in the interface region (between the bow and termination shocks). This effect may be very important for the interpretation of the kHz radiation detected by “Voyager”. Moreover, the asymmetric (in upwind and downwind directions) distributions of H atom number density, bulk velocity, and temperature may be observed on the basis of the scattered solar Lyman alpha radiation data.

We find it cliffScult in the frame of this model without interstellar magnetic field to reconcile the distance to the shock and heliopause deduced from the time delay of the radio emissions with other diagnostics and discuss possible explanations for these discrepancies, as the existence of an additional interstellar magnetic pressure (2.1 pG < B < 4 pG for a perpendicular magnetic field). We also conclude that on the basis of this model the most likely value for the proton density in the local interstellar cloud is in the range 0.04 cm -3 < np,LIC < 0.07 cm -3.