Well, if you measure the observable Universe from any direction on Earth it's about 15 billion light years - so you cannot be disproven declaring that the Earth is in the center of the Universe. But why? That's why the aliens of of Zeta Reticuli flew over here - to determine why in the hell Earth and its monkeys were so special. They found magic mushrooms, figured they were close enough to the answer - crashed a few ships while they were trippin - and went home hauling a magic mushroom farm. Very slowly. The speed of Light is constant in all local frames, are Gravity waves as well?