The impact on geosynchronous orbits due to fragmentation in graveyard orbit

Abstract At a distance of approximately 300 km from the Geostationary Orbit (GEO), there is a graveyard orbit where spacecraft that are no longer in operation are moved. When there is a disposal orbit close to a geosynchronous orbit, there is a need to study how such an operational orbit can be affected if there is a fragmentation event in the graveyard orbit, since this orbit contains a high number of objects that are subject to explosions and collisions. In view of this, this work aims to determine how geosynchronous orbit can be affected by a fragmentation event in a graveyard orbit. Thus, it was used a fragmentation model based on an isotropic velocity distribution to simulate an explosion in a graveyard orbit and the trajectory of the debris was propagated to verify and determine their interference in Geosynchronous orbits. For the trajectory propagation, it was considered the dynamic system of the two-body problem (Debris and Earth), added to the gravitational influence of the Moon and Sun, the Earth’s oblateness, and the solar radiation pressure perturbations. As main contributions, it was identified the conditions that lead to debris interfering in the geosynchronous region over time and it is proposed a new approach to estimate which debris will affect the geosynchronous region. The geosynchronous region most affected by fragmentation (over a period of 1 year and 5 years) is presented, which can be considered in evasive maneuvers. Moreover, the regions around the Earth that are affected by the debris cloud were determined and the dynamics of the debris cloud was investigated, so that variations in eccentricity, semi-major axis and inclination of the orbits were identified and a discussion on the perturbation effects is provided.