Evaluation of Atmospheric Drags for Satellites in Low Earth Orbit Using Various Atmospheric Models

Aerodynamic drags are the second in magnitude after the gravitational disturbance due to the Earth's oblateness for satellites operating in Low-Earth Orbit (LEO), and Any improvement on the knowledge of this drag disturbance will directly contribute to the accuracy of mission analysis and orbital predictions This work develops a general and three-dimensional code, named as APSL (Aerodynamic Properties of Satellites in LEO), for the accurate and fast calculation of aerodynamic drags for user-defined spacecraft geometries of arbitrary complexity, by incorporating in five widespread atmospheric models, including the USSA-1976, Jacchia-1977, NRLMSIS-00, JB2008 and DTM-2013. The APSL code is applied to the geodetic GOCE satellite to assess the sensitivity of aerodynamic drags to atmospheric models, and results show that satellite drags are primarily affected by atmospheric densities, while atmospheric temperature and molecular mass are mainly responsible for the change in drag coefficients. In terms of atmospheric densities and satellite drags, the former three models behave similarly as a whole, and the latter two models exhibit analogously.