Definitions of Various Geometrical and Physical Axises for the Elastic Earth Rotation

Based on the classical theory on the rotation of the elastic Earth, associated dynamical equations containing both nutation and wooble of Earth rotation have been deduced through introducing motion of the nutation frame system with respect to the inertial spatial frame. Therefore, the dynamical equations for polar motion and precession-nutation of various geometrical and physical axises have been given, including the Tisserand axis, rotation axis, instantaneous figure axis, momentum axis, CEP and CIP axis. Definition and relations among these axises have been demonstrated. It is indicated that the new dynamical equations are more comprehensive and easily understood than the existing dynamical equations on the Earth rotation, and wobble and nutation can be solved simultaneously, in particular, TOM in theory of Smith M. L. (1977) here only is a special solution. Theoretical formulae deduced in this paper are extension and improvement with respect to previous theory, and it can provide a reference for research on the dynamical geodesy and arstrogeodynamics.