Orbit integration in non-inertial frames


PhD. student, Royal Institute of Technology, SE 10044, Stockholm, Sweden


A precise orbit of a low Earth orbiting satellite helps us to compute the long wavelength structure part of the gravity field of the Earth. There are different methods and frames for orbit integration depending on the problem and satellite mission.
In this paper, the dynamic equations of the satellite motion are presented in different frames of navigation. A simple numerical study on a satellite orbit in local frames is also included. In these frames the geodetic coordinate of the satellite is directly integrated. Numerical studies confirm that the north-east-down frame is not stable for orbit integration either. However, the paper shows how to solve this problem by choosing a wander frame and its ability.