2.5D hybrid code simulation of the solar wind interaction with weak comets and related objects

Abstract

Bi-ion fluid simulations (Bogdanov et al., 1996; Sauer et al., 1995) have demonstrated several distinct features which occur in massloading zones associated with the interaction of the solar wind with comets, whose rate of gas production is small; specifically, bi-ion magneto-acoustic structuring and pulsations. Because of the limitated applicability of the bi-ion model, hybrid codes are used in order to check the results. The simulations were performed for gas production rates 5 × 10 24 s −1 ≤ Q ≤ 4 × 10 27 s −1 and for interplanetary magnetic field oriented perpendicular to simulation plane. In the case of Q < 10 25 s −1 the cometary atmosphere forms a strong cycloid-type tail. In case that Q ≥ 10 25 s −1, the cometary atmosphere forms a cone-type tail and structuring of the coma occurs. The results of these simulations apply to other weak solar wind massloading sources, e.g., the AMPTE releases, possibly Phobos and Deimos and possibly even Pluto. The results presented here may be important for studies of the dynamics of the ionized environment near the ‘Solar Probe’ spacecraft, in future.