maddad #fundie uplink.space.com
If the Sun were the center of the universe, then we would expect to see a difference in the speed of light through the ether depending on which side of the Sun the Earth was on. Since we see no difference in the speed of light at any time of year, we have to conclude that the Earth is at the center, not the Sun.
This puzzling fact was used by Einstein in his development of special relativity. SR is complex though, so Occam's Razor suggests that the better interpretation is that we are at the center. This does away with the need for SR.