Analytic perturbation solutions to the Venusian orbiter due to the nonspherical gravitational potential

The analytic perturbation solutions to the motions of a planetary orbiter g iven in this paper are effective for 0 < e < 1, where e is the orbital ecce ntricity of the orbiter. In the solution, it is assumed that the rotation o f the central body is slow, and its astronomical background Is clear. Examp les for such planets in the solar system are Venus and Mercury. The perturb ation solution is tested numerically on two Venusian orbiters with eccentri c orbits, PVO and Magellan, and found to be effective.