Longterm circular orbit propagation errors caused by Earth's anomalous gravity and drag parameter uncertainty
Abstract
Orbit propagations of lowaltitude artificial satellites are in general affected by various types of force model errors. More noticeable among them are the errors caused by the incorrect truncation of Earth's gravity field and by the uncertainty in the atmospheric drag model parameters. Considering these two types of errors, this work aims at developing a stochastic procedure to evaluate the order of magnitude of the accumulated global error in longterm circular orbit propagations. In both the Earth's anomalous gravity and drag parameter uncertainty cases, the statistical estimates of errors in orbital elements are obtained in terms of their covariances. After testing the theory in both the cases separately with some simple examples, it is combined to apply to a satellite with the orbital and structural configuration similar to that of the first Brazilian satellite, launched on 9th February 1993. The error estimates obtained have been compared with the true errors generated by a numerical procedure and analyzed in detail so as to make some conclusive remarks over the theory developed here. The results obtained in all the cases are reasonably good and conservative and the theory developed in shortterm propagations is found valid for longterm propagations too.
 Publication:

Graz International Astronautical Federation Congress
 Pub Date:
 October 1993
 Bibcode:
 1993graz.iafcQ....K
 Keywords:

 Circular Orbits;
 Long Term Effects;
 Orbit Calculation;
 Satellite Orbits;
 Satellite Perturbation;
 Earth Gravitation;
 Errors;
 Gravity Anomalies;
 Satellite Drag;
 Astrodynamics