This paper discusses the use of solar radiation pressure (SRP) augmented deorbiting to passively remove small satellites from high altitude Sun-synchronous orbits. SRP-augmented deorbiting works by deploying a light-weight reflective inflatable device to increase the area-to-mass-ratio of the spacecraft. The interactions of the orbital perturbations due to solar radiation pressure and the Earth’s oblateness cause the eccentricity of the orbit to librate at a quasi-constant semi-major axis. A large enough area-to-mass-ratio will ensure that a maximum eccentricity is reached where the spacecraft will then experience enough aerodynamic drag at the orbit pericentre to deorbit. An analytical model of the orbital evolution based on a Hamiltonian approach is used to obtain a first guess for the required area-to-mass-ratio to deorbit. This first guess is then used in a numerical propagation of the orbital elements using the Gauss’ equations to find the actual requirements as a function of altitude. The results are discussed and altitude regions for Sun-synchronous orbits are identified in which the proposed method is most effective. Finally, the implementation of the device is discussed. It is shown that passive solar radiation pressure deorbiting is a useful alternative to propulsive end-of-life manoeuvres for future high altitude Sun-synchronous missions
