Orbit maintenance of a lunar polar orbiter

We have developed an analytical theory for selenocentric orbits, suitable f or the mission analysis of low polar orbiters, such as the currently planne d global mapping missions. After outlining the methods and the results of t he theory, we present two examples of the use of the analytical propagator to study the eccentricity control for both a purely passive subsatellite an d for an actively manoeuvered spacecraft. These examples demonstrate the su perior efficiency, for this purpose, of the analytical theory with respect to numerical integration. (C) 1998 Elsevier Science Ltd. All rights reserve d.