Orbit of the Moon the perigee and apogee, respectively – makes one complete revolution every 8.85 Earth years, or 3,232.6054 days, as it rotates slowly in the same direction as the Moon itself (direct motion). The Moon's apsidal precession is distinct from the nodal precession of its orbital plane and axial precession of moon itself. The mean inclination of the lunar orbit to the ecliptic plane is 5.145°. Theoretical considerations show that the present inclination relative to the ecliptic plane arose by tidal evolution from an earlier near-Earth orbit with a fairly constant inclination relative to Earth's equator. It would require an inclination of
Earth, Moon, and Planets original research articles on formation of stars and planets, evolution of the Solar System including its origin, and the evolution of extra-solar systems including their origins. The focus also includes asteroids, comets, meteoroids, and near-Earth objects, Earth impact hazards, the Solar System-Earth relationship, and related topics. Research coverage encompasses physical and chemical properties of the above-mentioned celestial bodies, and their related chaotic behavior. This journal is abstracted and indexed in the following databases: Earth, Moon, and Planets Earth, Moon, and Planets is a peer-reviewed scientific journal, published approximately ten times per year by Springer Science+Business Media. It was established in