1Department of Astronomy, Nanjing University, Nanjing 210093, China
2Institute for Space Environment and Astrodynamics, Nanjing University, Nanjing 210093, China
Abstract:
Lunar physical libration, which is true oscillation of lunar equator in the space, alters the lunar gravitational field in the space coordinate system and affects the orbiting motion of lunar orbiters (hereafter called as lunar satellites) correspondingly. The effect is very similar to that of the precession and nutation on the earth satellites, and a similar treatment can be used. The variations in the gravitational force and in the orbit perturbation solution are clearly given in this paper together with numerical illustrations.