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Is there really any empirical proof that the earth moves round the sun?
I've read simple explanations using mass-gravity relation. But then some questions remain, is gravity a function of mass alone? Is mass a function of size alone? if the earth is revolving round itself, and the sun is revolving round and moving towards the black hole in the centre of the Milky Way, how can we be sure that these two movements alone do not suffice to explain night and day or change in the position of the stars with time?