Planetary Science Seminar winter-2014

The isotopic similarity of the Earth and Moon has motivated a recent investigation (Cuk and Stewart, 2012) of the formation of the Moon with a fast-spinning Earth. Angular momentum was found to be drained from the system through the evection resonance, a resonance between the pericenter of the Moon and motion of the Earth about the Sun. However, tidal heating within the Moon was neglected. Here we explore the coupled thermal-orbital evolution of the early Earth-Moon system, taking account of tidal heating within the Moon. Large tidal heating in the Moon significantly changes the tidal parameters in the Moon, with consequent early escape from the evection resonance. Insufficient angular momentum is withdrawn from the system to be consistent with the current configuration of the Earth-Moon system.