Models of satellite motion and the precision of the numerical prediction of orbits

Theoretical and experimental results are presented which indicate that the speed and precision of the numerical prediction of satellite orbits are significantly affected not only by the method of numerical integration but also by the motion model. Fundamental properties of a numerical method, such as approximation and stability, are closely connected with the basic characteristics of integrated models, which are determined by the choice of independent and dependent variables as well as by the orbit parameters. When integrating orbits with heights up to 35,000 km as well as arbitrary orbits of large eccentricity, preference should be given to a model in regular elements modified in accordance with Encke's method.