A Validation Procedure for Satellite Orbits and Force Function Models Based on a New Balance Equation Approach

Abstract

Since the availability of CHAMP and GRACE data, the energy approach has become an important tool for the recovery of the gravity field based on continuously observed satellite orbits. Up to now, only the total energy of the satellite’s three-dimensional motion has been considered which is known as the Jacobi integral if formulated in a constantly rotating Earth-fixed reference frame. Beside this, additional energy integrals can be found for the components of the satellite’s motion and various combinations hereof, starting from the three scalar components of Newton’s equation of motion. Furthermore, integrals of motion based on the linear momentum and the angular momentum can be formulated which show even better mathematical characteristics than the Jacobi integral for the determination of the gravity field. Therefore, this new approach seems to be appropriate to validate the consistency of gravity field models and precisely observed satellite orbits and to improve, subsequently, these gravity field models. The advantages and critical aspects of this approach are investigated in this paper. First results with real data were presented using kinematic CHAMP orbits.