With even a simple telescope, it's possible to see the international space station zoom through the sky, if only for a moment. The outline is very clear, and depending on the quality of the optics, atmospheric conditions, etc., quite a lot of detail can be made out.
This, on top of the fact that you can get the precise location of it at any given time, is pretty damning evidence for a flat earth.
How does the flat earth hypothesis explain the consistency of the ISS orbit and the easily obtained details when viewed through a telescope?
If not in orbit, it is propelled by a force other than gravity, and if so, what is this force? There needs to be at least three forces at work for it to rotate in a circle above the plane. And upward force to keep it suspended, and at a minimum two forces to move it in a circular fashion. Conventional fuel burning would need eventual refueling, which doesn't occur.
It cannot be a mere weather balloon as I've seen suggested by some FE'rs, and I don't think any explanation given by flat earth hypothesis will follow the Zetetic method, but I hope to be shown otherwise!
Also, the myriad other satellites need an explanation although it's usually harder to discern visual details on them, given their various respective sizes and distances from the earth.