The effects of gravity are perfectly known for our scientists. We can calculate the force of gravity produced by two objects depending on their mass and distance, for example. We can't explain what causes it, we can only especulate. By the way do you Flat Earthers know what causes UA?
In your case, some believe that the stars are actually there magically orbiting, others believe that the stars are just projections. Well that seems like a major disagreement.
And of course, like Umurweird said, you don't even have a map of the Flat Earth (not a correct one at least).