Astrometric obs. of Phobos and Deimos in 1971

Accurate positional measurements of planets and satellites are used to improve our knowledge of their dynamics and to infer the accuracy of planet and satellite ephemerides. In...对行星及卫星的高精度位置测量，可用于深化对其动力学特性的认知，并可用于推导行星与卫星星历表（ephemerides）的精度。In...