On the Long Term Evolution of Graveyard Orbits

Abstract

In order to avoid a potential collision hazard due to space debris, abandoned geostationary satellites are normally reorbited after their operational phase into a so called graveyard orbit a few hundred km above the geostationary altitude. This paper presents the method and the results of a study on the long term evolution of such orbits under the influence of perturbations, especially those of solar pressure effects according to a realistic model which considers the shape, surface properties and attitude of the satellite. The long term orbit prediction software of J. Kwok was modified and used to evaluate the long term evolution of graveyard orbits. For the case of a gravity gradient stabilized attitude, which was found to be a rather unlikelysituation, a secular variation of the perigee height was obtained with reasonable assumptions on the surface properties of solar arrays.