Full Physics Orbital Simulation around Comet Didymos for CubeSat MissionAPEX on HERA, ESA

Sammanfattning: We investigate the dynamic environment of the double asteroid system (65803) Didymoswith its satellite Didymos B for stable trajectories of more than 30 days for a model cubesatcalled APEX, foreseen to visit Didymos with the HERA mission, to be launched in 2023.We find semi-stable orbits with lifetimes up to 15 days under the influence of solar radiationpressure. In comparison, in the absence of solar radiation pressure, orbit trajectories reachlifetimes of up to 90 days. We present the distribution of orbital stability for positionsof initial deployment and the related orbital lifetime for inclinations of i = 0, 6 and 30 to the ecliptic plane of the sun, to investigate expected seasonality of the Didymossystem. The influence on trajectories through solar radiation pressure on the arrangementof the solar panels of APEX is compared to trajectories without solar radiation pressure. Itbecomes clear that the influence of solar radiation pressure is the main variable for stabilityof trajectories and must be further investigated with great care. We also discuss briefly theoperation of APEX in relation to orbital corrections and the limitations for such corrections.