Using WACCM-X neutral densities for orbital propagation: Challenges and solutions

Atmospheric drag is a major perturbation in Low Earth Orbit (LEO). The neutral density obtained from atmospheric models is a major source of uncertainty in drag calculations and therefore orbital propagation in LEO. Many atmospheric models are available, with fast empirical models most commonly used. We explore the challenges and benefits of using numerical models, specifically the Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension (WACCM-X) as part of the Community Earth System Model (CESM). Numerical models provide higher resolution of thermospheric structures, along with more accurate neutral density forecasts through assimilative models such as the Advanced Ensemble electron Density Assimilation System (AENeAS). Solutions are presented to overcome the challenges of using numerical models for neutral densities.