Autonomous orbit determination for earth satellites by starlight atmospheric refraction

An approach of autonomous navigation for satellites is described using refraction measurements of starlight passing through the upper atmosphere. An Extended Kalman Filter (EKF) is designed to estimate the satellite's position and velocity. Simulation for a sun-synchronous orbit satellite is done. Results show that the satellite's position accuracy is about 0.038km. Moreover, results show that the measurement error of starlight refraction angle and the uncertainty of the atmospheric refraction model are two principal factors deteriorating the navigation accuracy.