Improving Space Object Catalog Maintenance Through Advances in Solar Radiation Pressure Modeling

Abstract

This paper investigates the weaknesses of using the cannonball model to represent the solar radiation pressure force on an object in an orbit determination process, and it presents a number of alternative models that greatly improve the orbit determination performance. These weaknesses are rooted in the fact that the cannonball model is not a good representation of the true solar radiation pressure force acting on an arbitrary object. Using an erroneous force model results in poor estimates, inaccurate trajectory propagation, unrealistic covariances, and the inability to fit long and/or dense arcs of data. The alternative models presented are derived from a Fourier series representation of the solar radiation pressure force. The simplest instantiation of this model requires only two more parameters to be estimated, however, this results in orders of magnitude improvements in tracking accuracy. This improvement is illustrated through numerical examples of a discarded upper stage in a geosynchronous transfer orbit, and more drastically for a piece of high-area-to-mass ratio debris in a near-geosynchronous orbit. Implementation of improved solar radiation pressure models in this manner will alleviate track correlation, object identification, and sensor tasking issues that plague current catalog maintenance due to the inaccurate standard dynamic model.