1. Astronauts have seen and proved that the earth is round.
2. When to look long at a ship leaving for horizon it will partially disappear because of the earth bending
3. Even in Lockheed U-2 plane pilots can see the earth bending.
Fasten your seat belts and get ready for the Flat Earthers answers to your
proofs!
I guess they will reply like this:
1. Astronauts are fake, no one can go in the outer space, the outer space is fake
2. The ship doesn't disappears below the horizon but it is a matter of perspective
3. Lockheed U-2 planes are fake, and their "pilots" are liars.
These are some of the
arguments they struggle to use to back their theories.

Getting back to reality, everything you wrote makes sense to all of us but for them,
they are gone full retard.