Disposal orbits for GEO spacecraft: A method for evaluating the orbit height distributions resulting from implementing IADC guidelines

Geostationary orbit (GEO) is the most commercially valuable Earth orbit. The Inter-Agency Space Debris Coordination Committee (IADC) has produced guidelines to help protect this region from space debris. The guidelines propose moving a satellite at the end of its operational life to a disposal orbit, which is designed so that satellites left there will not infringe the operational GEO region within a period of at least 100 yr. Standards are being developed through the International Organisation for Standardization to translate the IADC guidelines into engineering practice. This article presents an analytical method for calculating the distribution of final orbits assuming the IADC guidelines in GEO are implemented, as a function of distributions of satellite parameters (mass per unit area, solar radiation pressure reaction coefficient), the fuel measurement uncertainty, and the desired reliability of the disposal manoeuvre. Results show that typically the fuel measurement uncertainty dominates the distribution of perigee heights rather than the scatter in satellite properties or desired manoeuvre reliability. The method is simple to implement and allows the effects of changes in system parameters to be evaluated quickly.