Extended Data Figure 6 : Early tidal evolution of the Moon with Earth initially having a 2-h spin period.

From: Tidal evolution of the Moon from a high-obliquity, high-angular-momentum Earth

Extended Data Figure 6

This is equivalent to the system having twice the current AM. The grey lines plot a simulation in which the tidal properties of Earth and the Moon were QE/k2,E = QM/k2,M = 100 throughout. The black line shows a simulation branching at 30 Myr by changing QE/k2,E to 200. Although the final obliquity of Earth (e) is correct, the final AM of the Earth–Moon system (b) somewhat exceeds the current value of 0.35 × . a, c and d plot the semimajor axis, eccentricity and inclination of the Moon.