A STUDY OF PERTURBATION EFFECT ON SATELLITE ORBIT USING COWELL’S METHOD

Abstract. Most Keplerian problems were treated as ideal or under the basic assumptions that the motion of a body in the orbits is a result of the gravitational attraction between two bodies. This ideal situation does not exist. Additional forces acting on any moving body must be taken into account. These additional forces are called the perturbing forces. The perturbing forces that cause the satellite orbit to deviate from a theoretically regular orbital motion can be divided into two categories, conservative field forces and non-conservative perturbing forces. The conservative perturbing forces are due to other celestial bodies such as Moon, Sun and etc. Solar pressure, atmospheric drag, thrust and the non-homogeneity and oblateness of the Earth are the examples of the non-conservative perturbing forces. This paper discusses the study of perturbation of a satellite orbit due to the presence of other gravitational bodies such as Moon and Sun from the conservative perturbing forces and from the non-conservative perturbing forces such as the non-homogeneity and oblateness of the Earth, atmospheric drag and thrust. To solve this perturbed problem of Keplerian orbit, Cowell’s method will be used, followed by Runge-Kutta method to simplify the equations involved