Data Assimilation for better global neutral density specification and forecast

Neutral density measurements are difficult to make, limited in number and coverage, andoften suffer from large and poorly specified uncertainties. This makes the option to im-prove neutral density specification using thermosphere/ionosphere measurements veryattractive for satellite collision avoidance applications. Better neutral density specificationand forecast can reduce the uncertainty in satellite and debris positioning, lower satellitefuel consumption, and help prevent the Kessler Syndrome. Using the Thermosphere Iono-sphere Data Assimilation (TIDA) package, we investigate whether it is possible to improveglobal thermosphere neutral density results by assimilating a variety of measurementstaken within the thermosphere/ionosphere system.