Date of Award


Document Type


Degree Name

Master of Science in Astronautical Engineering


Department of Aeronautics and Astronautics

First Advisor

Bryan D. Little, PhD


The second space race is looming on the horizon, and the Moon is again at center stage. All major space fairing nations have plans for future Lunar exploration, but this time with plans to stay. NASA’s Artemis program plans to put humans back on the Moon in 2025 and establish a Lunar base on the South pole in the 2030s. Meanwhile, China has landed a rover on the far side of the moon with a communications relay satellite in a halo orbit around the L2 Lagrange point, and partnered with Russia to build a Lunar research station on the Lunar South pole in the 2030s. These missions, along with the discovery of large concentrations of ice on the Lunar South pole, indicate a congested future in cislunar space. Clearly, a robust cislunar Space Situational Awareness (SSA) architecture is needed to enable safe and secure operations. The periodic orbits around the triangular Lagrange points present a potential solution to this complex problem. This research analyzes the suitability of planar L4 and L5 Lagrange point orbits for a cislunar SSA mission. Orbits are analyzed individually, as well as, in constellations to determine the most effective mission architectures, specifically, for monitoring objects in L1 and L2 halo orbits. The visibility of a cislunar objects is determined by calculating visual magnitude, and the Circular Restricted Three-Body Problem (CR3BP) is used as a basis for the modeling and simulation. Results of this analysis demonstrate that planar L4 and L5 orbits can be suitable for the stated SSA mission. Specifically, constellations of satellites in both L4 and L5 orbits are able to obtain near constant visibility times on L1 and L2 halo orbit objects.

AFIT Designator



A 12-month embargo was observed.

Approved for public release. Case number on file.