Satellite observations allow the reconstruction of the gravity field of the Earth-Moon system. The data obtained from satellite observations are used to reconstruct inhomogeneities in the Earth"s interior and related dynamic processes. The theory of variations in the Earth"s gravity field due to the variations in the rotation of the Earth is discussed in detail. Further a critical assessment of the hypothesis of the expanding Earth is presented on the base of recent astronomical and satellite data as well as linear laser ranging. Readers will find a thorough overview over the interdisciplinary fields of space geodesy, geodynamics and physics of the Earth"s interior.