Effects of Major Errors Sources on Planetary Spacecraft Navigation Accuracies

Tighter accuracy requirements on future planetary missions, than on past missions, make it desirable to improve 1) the accuracy of real-time state estimates and 2) the reliability of preflight state estimate error statistics. This paper is addressed to the second problem area. The sources of the major errors in the Earthbased tracking system are listed and discussed, and the effects of these errors on the predicted spacecraft orbit determination accuracies for two future interplanetary missions are presented.