EUROPEAN SPACE AGENCY
EUROPEAN SPACE OPERATIONS CENTRE
GROUND SYSTEMS ENGINEERING DEPARTMENT
Mission Analysis Office
CLASSIFICATION OF GEOSYNCHRONOUS OBJECTS
4.7 Objects in a libration orbit around both stable points
In this list there are objects which were in a libration orbit around both stable points according to their last available TLEs. The following data are given:
It is important to note that this category is special and only a very small number of objects is concerned. It is a borderline case, just between a libration around one stable point and a drift around the Earth. Thus, some perturbations which could be neglected in the other cases have a strong influence here. The main consequence is that this category is more sensitive to errors in the measurements than the others and the libration period may have a low accuracy.