Eccentricity e of the satellite at equilibrium P as a function of the parameters. The solutions lie on a three-dimensional surface shown here from two viewing angles. This figure is obtained by stitching together the patches represented in Fig. C.1. For better comparison, the dividing curves are drawn on the surface using the same colour code. The top tube-like portion of the surface has been cut; as shown in Fig. C.1, it extends up to a → ∞ (i.e. u → 0). The equilibrium P is singular along the magenta curve, called in the text.