Utilization of Space-Based TDoA and FDoA for Cislunar Orbit Determination

Utilization of Space-Based TDoA and FDoA for Cislunar Orbit Determination

Presented at the Advanced Maui Optical and Space Surveillance Technologies (AMOS) 2022 Conference

Michael R. Thompson, Matthew D. Popplewell, Bradley Cheetham

ABSTRACT

This study evaluates the potential observability benefits of space-based passive RF systems compared to other ground-based and space-based observers for cislunar Space Domain Awareness. TDoA and FDoA observations are used for orbit determination of objects in the lunar vicinity using observers in GEO and XGEO. The results are compared to ground-based observations in order to analyze the performance gains over existing architectures. Results show using space-based systems result in faster filter convergence and more accurate state estimates.

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CAPSTONE Mission Operations Update: Initial Recovery Successful

CAPSTONE Mission Operations Update: Initial Recovery Successful

Over the past couple of weeks, the CAPSTONE mission team has been working to resolve an anomaly that occurred early last month and resulted in the spacecraft losing full 3-axis attitude control and entering into a spin stabilized state. Through extensive analysis and evaluation supported by a dedicated team of individuals on the mission team and key partners, the most likely cause of the anomaly was identified as a valve related issue on one of the spacecraft’s eight (8) thrusters. The partially open valve resulted in thrust from the associated thruster whenever the propulsion system was pressurized. To attempt a recovery from this condition, the mission team conducted multiple tests on the vehicle and evaluated extensive telemetry and simulation data and then formulated a plan for attempting recovery of the vehicle’s full 3-axis control. (more…)