Fig. 4

Distributions of Mg and Ca atoms seen from the south using test particle simulations at perihelion. The color scale, which is displayed on a logarithmic scale, corresponds to the line-of-sight integration of the amount of the exosphere seen from the south as MASCS also observed from the south. The drawn atomic distributions are 60 min after the simultaneous ejection from -100°E (red arrow). Note that the absolute value of the color scale does not have physical meaning. It can be seen that Ca tends to flow in the anti-sunward direction, unlike Mg. Note that these results do not match observations, since atoms were ejected only once and only from the single point