Greetings, One of the basic postulates of relativity is that the laws of physics hold equally well in all frames of references. This got me wondering about the geocentric model of solar system which necessarily gives rise to motions of peculiar kinds. For example, the epicycles, which are needed in this model to explain the motion of our planets. This kind of motion seems irregular with regard to the laws of motion and a possible violation of these laws. Hence, my question: Is there anything in special/general relativity, that could account for the motion of planets as observed from the Earth's frame of reference? Thank you!