On the secular recession of the Earth-Moon system as an azimuthal gravitational phenomenon

Abstract

We here apply the ASTG-model to the observed secular trend in the mean Sun-(Earth-Moon) and Earth-Moon distances thereby providing an alternative explanation as to what the cause of this secular trend may be. Within the margins of observational error; for the semi-major axis rate of the Earth-Moon system, in agreement with observations (of Standish and Kurtz, Proceedings IAU Colloquium, IAU, pp. 163–179, Cambridge University Press, Cambridge, 2005), we obtain a value of about +(5.10±0.10) cm/yr. The ASTG-model predicts orbital drift as being a result of the orbital inclination and the Solar mass loss rate. The Newtonian gravitational constant G is assumed to be an absolute time constant. Krasinsky and Brumberg (Celest. Mech. Dyn. Astron. 90(3–4):267–288, 2004); Standish and Kurtz (2005) reported for the Earth-Moon system, an orbital recession from the Sun of about +(15.00±4.00) cm/yr and +(7.00±2.00) cm/yr respectively; while Williams et al. (Phys. Rev. Lett. 93:261101, 2004); Williams and Boggs (Proceedings of 16th International Workshop on Laser Ranging, Space Research Centre, Polish Academy of Sciences, Poland, 2009), Williams et al. (Planet. Sci. 3(1):2, 2014) report for the Moon, a semi-major axis rate of about +(38.08±0.04) mm/yr from the Earth. The predictions of the ASTG-model for the Earth-Moon system agrees very well with those the findings of Standish and Kurtz (2005), Krasinsky and Brumberg (2004). The lost orbital angular momentum for the Earth-Moon system—which we here hypothesize to be gained as spin by the two body Earth-Moon system; this lost angular momentum accounts very well for the observed Lunar drift, therefore, one can safely say that the ASTG-model does to a reasonable degree of accuracy predict the observed Lunar semi-major axis rate of about +(38.08±0.04) mm/yr from the Earth.