Assessment of Earth Albedo Effect on Temperature-based Orbit Estimation

The Earth albedo has a significant effect on temperature variations on surfaces of an Earth-orbiting satellite. The albedo heat flux is usually modeled as a fraction of solar flux, and its intensity is specified by the albedo factor. While the thermal control theory assumes a constant mean value of 0.34 as the Earth albedo factor, its value strongly depends on the reflectivity characteristics ofthe satellite sub-point. In this regard, the present study has focused on investigating the effect of albedo factor modeling on the performance of the recent method of temperature-based orbit estimation. To this aim, Unscented Kalman filter is adopted for the orbitestimation (OE) via temperature data, and OE performance is analyzed using different albedo models like constant factor and CERES model. In addition, the uncertainty of the albedo model due to the climate condition is modeled by white Gaussian noise. Theobtained results from Monte Carlo simulations demonstrate severe sensitivity of the orbit estimation to the albedo model accuracy.

Keywords:

satellite surface’s temperatures , orbit estimation , Earth’s albedo , albedo factor , UKF