The remarkable noises of star sensor mainly come from CCD image sensor

and control and data processing circuit

and effect of these noises on precision of attitude estimation can not be ignored. On the basis of studying CCD image sensor noises such as photon shot noise

dark current noise

charge transfer noise and readout noise

their effects on extraction precision of subpixel centroid method are analyzed. According to results of subpixel centroid method satellite attitude is calculated by use geometric analytic OLAE method. Simulation results show that star sensor noise model has higher precision of attitude estimation compared with the model which only introduces Gaussian white noise.