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In this report we discuss the self-consistent dynamics of pickup ions in the solar wind flow around the lunar-like object. In our model the solar wind and pickup ions are considered as a particles, whereas the electrons are described as a fluid. Inhomogeneous photoionization, electron-impact ionization and charge exchange are included in our model. The Moon will be chosen as a basic object for our modeling. The current modeling shows that mass loading by pickup ions H + , H 2 + , He + , and Na + may be very important in the global dynamics of the solar wind around the Moon. In our hybrid modeling we use exponential profiles for the exospheric components. The Moon is considered as a weakly conducting body. Special attention will be paid to comparing the modeling pickup ion velocity distribution with ARTEMIS observations. Our modeling shows an asymmetry of the Mach cone due to mass loading, the upstream flow density distribution and the magnetic field. The pickup ions form an asymmetrical plasma tails that may disturb the lunar plasma wake.

In this report we discuss the self-consistent dynamics of pickup ions in the solar wind flow around the lunar-like object. In our model the solar wind and pickup ions are considered as a particles, whereas the electrons are described as a fluid. Inhomogeneous photoionization, electron-impact ionization and charge exchange are included in our model. The Moon will be chosen as a basic object for our modeling. The current modeling shows that mass loading by pickup ions Na + and He + may be very important in the global dynamics of the solar wind around the Moon. In our hybrid modeling we use exponential profiles for the exospheric components. The Moon is considered as a weakly conducting body. Special attention will be paid to comparing the modeling pickup ion velocity distribution with ARTEMIS observations. Our modeling shows an asymmetry of the Mach cone due to mass loading, the upstream flow density distribution and the magnetic field. The pickup ions form an asymmetrical plasma tails that may disturb the lunar plasma wake.

In this report we discuss the ion velocity distribution dynamics from the 3D hybrid simulation. In our model the background, pickup, and ionospheric ions are considered as a particles, whereas the electrons are described as a fluid. Inhomogeneous photoionization, electron-impact ionization and charge exchange are included in our model. We also take into account the collisions between the ions and neutrals. The current simulation shows that mass loading by pickup ions H(+); H2(+), CH4(+) and N2(+) is stronger than in the previous simulations when O+ ions are introduced into the background plasma. In our hybrid simulations we use Chamberlain profiles for the atmospheric components. We also include a simple ionosphere model with average mass M = 28 amu ions that were generated inside the ionosphere. The moon is considered as a weakly conducting body. Special attention will be paid to comparing the simulated pickup ion velocity distribution with CAPS T9 observations. Our simulation shows an asymmetry of the ion density distribution and the magnetic field, including the formation of the Alfve n wing-like structures. The simulation also shows that the ring-like velocity distribution for pickup ions relaxes to a Maxwellian core and a shell-like halo.

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 × 1024s−1 ≤ Q ≤ 4 × 1027s−1 and for interplanetary magnetic field oriented perpendicular to simulation plane. In the case of Q < 1025s−1 the cometary atmosphere forms a strong cycloid-type tail. In case that Q ≥ 1025s−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.

The paper reviews the studies of collective plasma processes responsible for anomalously fast exchange of energy between the plasma components, for a structure of the boundaries of the characteristic regions in the zone of the comet interaction with the solar wind, and for the anomalous transport across these boundaries. The position and structure of the cometary bow shock are obtained by numerical simulation using the particles in cells method. To study different plasma instabilities in the cometary atmospheres the simple analytic model of the cometary plasma environment is used that is based on the semikinetic description of the solar wind loading by cometary ions. The influence of a self-consistent electric field on the cometary plasma outflow is briefly discussed.