FIGURE 4.

Tidal evolution of the Earth-Moon system in evection with damped libration for A = 10 and starting angular momentum L_o = 2L_EM. (a) Scaled lunar semi-major axis, a′, as a function of time. (b) The stationary state eccentricity squared, ${\epsilon }_s\equiv e_s^2$, vs. time. (c) The stationary state eccentricity squared vs. lunar semimajor axis during the evolution. (d) Time variation of the system angular momentum, L, the Earth and Moon spin rates, s, s_m, the angular momentum of the lunar orbit, L_orb and its mean motion, n. The gray region represents the stage where eccentricity is increasing.