Question of the week: Is there any scientific evidence that supports the flat-Earth hypothesis?
My brief answer: There is no rational scientific evidence for a flat earth. If you take a flight from Athens to Johannesburg at night, which I have done, or any north–south flight where you cross the equator and look out the window, you will see the stellar constellations slowly turn upside down. Such an experience would be impossible if Earth was flat. Note, too, that the shortest possible flights between distantly apart cities always traverse a curve. For a spherical Earth, the shortest distance between two distantly apart points on the surface is always a curve and never a straight line.
Then there is the crow’s nest effect. The higher you are above Earth’s surface, the farther away you can see, because you are able to see farther across the surface of a spherical Earth. At elevations greater than 45,000 feet above sea level one can see the curvature of Earth’s surface, something I have also personally witnessed. A corollary to the crow’s nest effect is that at any height above Earth’s surface one can see the tops of distant objects but not the bottoms. The sphericity of Earth hides the bottom from view.
A not-so-scientific piece of evidence that Earth cannot be flat is that if Earth were flat, cats would have knocked everything over the edge by now.