[https://en.wikipedia.org/wiki/True_polar_wander True polar wander is a solid-body rotation of a planet or moon with respect to its spin axis, causing the geographic locations of the north and south poles to change, or "wander". If a body is not totally rigid (as is the case of the earth), then in a stable state, the largest moment of inertia axis will be aligned with the spin axis, with the smaller two moments of inertia axes lying in the plane of the equator. If the body is not in this steady state, true polar wander will occur: the planet or moon will rotate as a rigid body to realign the largest moment of inertia axis with the spin axis... If the body is near the steady state but with the angular momentum not exactly lined up with the largest moment of inertia axis, the pole position will [[:Категория:Прецессия|oscillate]].]