Funny we don't have atmospheric distortions today, and can measure the distance to the moon, sun and many other planets and stars.
We can measure the distance to the next house, skyscraper and mountain in the same way. All wil incredible precision.
Flat Earth is impossible. Meaning... NOT POSSIBLE.
Who knows for sure, but it was probably atmospheric distortions that got the whole FE thing started in the first place... I mean in this modern day and age. But anybody can go outside on a clear night and watch the stars twinkle. How much are they displaced by their distortion twinkle? Perhaps a tiny fraction of a degree... not enough to create all the distortion and reverse distortion needed to show a FE. Bu, a person has dreams... even FE people do.