Orbit error due to gravity model error.

Many gravity fields have been constructed for the Earth based on various combinations of surface and satellite observations. Since none of these data sets are truly uniform in accuracy or coverage, the models are necessarily deficient to some extent in their ability to model satellite motion. If the covariance of the gravity models errors is known then an analysis of the expected orbit error can be performed. The details of this analysis is presented here along with examples using current gravity models.