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Аннотация:It is known that lunar center of mass (COM) does not coincide with the center of figure (COF), and the line "COF / COM" deviates from it to the South - East. Here we study the deviation COM to the East from the mean direction to Earth.
At first, we consider the optical libration of a satellite with synchronous rotation around the planet for an observer at a point on second orbit focus. Given this effect, a mechanism of tidal secular evolution of the Moon's orbit offered that explains approximately one fifth of the known displacement of the COM to the East. Thus, from alternative - evolution of the Moon's orbit with a decrease or increase in eccentricity - only the scenario of evolution with a monotonous increase in orbit eccentricity agrees with the displacement of lunar COM to the East. The available precise calculations confirm that now the eccentricity of the lunar orbit is actually increasing and therefore in the past it was less than its modern value.
To fully explain the displacement of the Moon’s COM to the East was deduced a second mechanism, which is based on the reliable effect of tidal changes in the shape of the Moon. The differential equation which governs the process of displacement of the Moon's COM to the East with inevitable rounding off its form is derived. The second mechanism also predicts that the elongation of the lunar figure in the early epoch was significant. Applying the theory of tidal equilibrium figures, we can estimate how close to the Earth the Moon could have formed.