SATELLITE ORBIT CALCULATIONS USING GEOPOTENTIAL COEFFICIENTS UP TO HIGH-DEGREE AND ORDER

First and higher order perturbations due to geopotential coefficient up to 360 degree and order are calculated using the analytical theory of artificial satellite motion. The theory is based on the geopotential expansion modified by introducing generalized lumped coefficients. The perturbations in the nonsingular orbital elements as well as in the components of the radius vector are calculated. The results for certain low satellite orbits obtained using 360 x 360 OSU91A gravity model are analysed. Precise calculations of geopotential perturbations as well as spectrums of perturbations for orbits of a few satellites (ERS-1, TOPEX) are analyzed using GEM-T2, GEM-T3 and GRIM14 models.