The evolution of the Earth-Moon system

The tidally-induced couple acting on the Moon, due to friction between the oceans and their beds, is calculated as a function of the Earth-Moon separation. The function is found to be proportional to 1+d/R ³ , and not the previously used 1/R ⁶. By use of this new function it is found that the present rate of lunar recession gives an acceptable history for the system if it is assumed the Moon was initially in a close geo-stationary orbit 4 billion years ago, when perturbed by the condensation of the Earth's core.