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
Near-Earth object to its close approach. The designation was similarly removed from asteroid catalogues when the observed object was identified with "Gaia", ESA's space observatory for astrometry. When a near-Earth object impacts Earth, objects up to a few tens of metres across ordinarily explode in the upper atmosphere (usually harmlessly), with most or all of the solids vaporized, while larger objects hit the water surface, forming waves, or the solid surface, forming impact craters. The frequency of impacts of objects of various sizes is estimated on the basis of orbit simulations of NEO populations, the frequency of impact craters on the Earth