Long-Term Simulation of Objects in High-Earth Orbits

This report (Part I of the Study Note of Work Package 2) presents the results obtained by applying the most accurate and complete long-term orbit propagator used in SDM 4.0 to study specific problems involving the MEO and GEO orbital regimes. In particular, the following topics were investigated: 1. The long-term evolution of GEO disposal orbits and the role in it of the initial eccentricity vector; 2. The identification of initial orbit elements and area-to-mass ratios leading to synchronous high eccentricity orbits like those recently discovered by the ESA 1 m telescope in Tenerife; 3. The orbital lifetime of objects in Molniya-like orbits as a function of initial conditions and operational practice. The long-term evolution of objects placed in the graveyard orbits used or proposed for the navigation satellites in MEO, in particular Galileo, is addressed in a companion report (Part II of the Study Note of Work Package 2).