Tidal dissipation in the Moon

Dissipationof tidalenergy in the moon _as calculated under the ssumptlon that it can be represented as due to imperfect elasticity.If the factor 1/Q for dissipation per cycle is assumed to be 1/100 for distortional strain energy and 1/lO00 for dilational strain energy, the heat now beir_g generated in the moon by tides is less than .OlO ergs/gm/yr.:i.e., negligible compared to radioactive heating by a chondritic composition.Tidal heating would be comparable to radioactive heating, howeverj if the .rsemi-major axis of the moon's orbit was one-third as gre_t, so the mechs_ism does limit the possible history of the moon's orbit.Also, appreciable tidal dissipation would cause thermal stresses and be conducive to convection, since it is much greater in the center than near the surface of the moon: and has a non-uniform distribution in latitude (and longitude as well, if rotation is synchronous with revolution). ::Ur_ _d others [1959] suggested that tidal dissipation may have _igm.ific_tlycontributed to heating of the moon's interior in the past.[1962] has calculated the tidal d:i.ssipation in a moon assumed to be | fluid wlth Newtonian viscosity.However, since tidal distort±cn is :elatlvely high frequency phenomenon, it seems a more modest extrapolati n from experience to assume that tidal dissipation in the moon occurs as, a result of imperfect elasticity with a factor 1/Q for dissipation per cyc3e comparable to those estimated for the earth's mantle from polar tides, cscillations_ and latitude variation.