Leveraging xGEO Orbits for Cislunar Space Domain Awareness

With recent interest in using cislunar orbits for a variety of missions, it is more important than ever to also have cislunar space domain awareness. This thesis aims to bridge the gap between traditional LEO/GEO architectures and the new cislunar orbit architectures with orbits higher than GEO but still within the Earth sphere of influence, called xGEO. This research effort first explores the feasibility of xGEO orbits by examining the errors that the two-body assumption builds over time. Findings suggest that the two body assumption can be used to varying degrees depending on the orbit radius. This study has found that regardless of radius from 2-5xGEO, when the orbit is in the lunar plane, the majority of the error is in-track. The study then evaluates how well these orbits perform when observing a lunar mission test satellite. Lastly, this study explores the possibility of using xGEO orbits for an inspection mission at L1. Using a circular restricted three body (CR3BP) model, trajectories were successfully created from 2-5xGEO using the stable manifolds with minimal Delta v and time of flight. Results show diminishing returns in both Delta v and time of flight between 3 and 4xGEO.