High Fidelity Dynamics Modeling for Near Earth and Cislunar Space Incorporating Non Conservative EffectsRobinson, Audra Cislunar SpaceHigh-Fidelity ModelingxGEOSGP4Aerospace EngineeringB SSpace Situational Awareness aims to provide comprehensive and accurate knowledge of all near-Earth-orbiting objects, now extending to the cislunar realm. This requires maintaining a catalog of space objects' states (position and velocity), with numerical simulations filling observational gaps. A high-fidelity orbit propagation model is developed using a cannonball spacecraft assumption and incorporating perturbative effects from spherical harmonics, Luni-Solar third-body influences, atmospheric drag, and solar radiation pressure. The model is compared with standard solvers such as Simplified General Perturbations 4 (SGP4) for spacecraft in Low Earth Orbit (LEO), Medium Earth Orbit (MEO), Geostationary Orbit (GEO), and the cislunar domain. Error analysis reveals that SGP4 exhibits exponentially increasing inaccuracies over time, making it suitable for short-duration predictions. Additionally, long-term trends in orbital element evolution due to perturbations are examined. Finally, cislunar orbit designs at various resonant frequencies are analyzed and compared with SGP4. These findings offer insights into orbital evolution, the limitations of SGP4 over extended time frames, and the role of high-fidelity modeling in optimizing orbit design in near-Earth and cislunar space.Roshan Thomas Eapen, Thesis SupervisorSven Schmitz, Thesis Honors Advisoropen_access2025-04-23T23:32:04Zhttps://honors.libraries.psu.edu/catalog/9756awr5604