John, correct me if I'm wrong, but I see three ways we could dis-prove geocentrism:

1) If we were able to observe all matter in the universe, and we saw that in fact we weren't located at the center of mass.

2) If we could detect that we were passing through the ether which was shown to be stationary with respect to the stars.

3) If we repeated the ether experiments like the MM experiment on mars and got the same result as on earth.