Moon's perigee mass as a missing component of the Earth's   precession-nutation theory
  In this work, the nutation momentum acting upon the Earth from the Moon's perigee mass that has not been taken into account in the Earth's precession-nutation theory was revealed. This missing momentum exhibits itself in the so-called "local latitude variation" with the Chandler's period. The results of our work raise the question of updating the Earth's precession-nutation theory and revising some postulates of the time service, astronomy, geophysics, satellite navigation, etc. 
D. G. Kiryan and G. V. Kiryan
physics.geo-ph astro-ph.EP