155) Some people claim to have seen the curvature of the Earth out their airplane windows. The glass used in all commercial airplanes, however, is curved to remain flush with the fuselage. This creates a slight effect mixed with confirmation bias people mistake for being the alleged curvature of the Earth. In actuality, the fact that you can see the horizon at eye-level at 35,000 feet out both port/starboard windows proves the Earth is flat. If the Earth were a ball, no matter how big, the horizon would stay exactly where it was and you would have to look DOWN further and further to see the horizon at all. Looking straight out the window at 35,000 feet you should see nothing but "outer-space" from the port and starboard windows, as the Earth/horizon are supposed to be BELOW you. If they are visible at eye level outside both side windows, it’s because the Earth is flat!
The aeronaut can see for himself that Earth is a Plane. The appearance presented to him, even at the highest elevation he has ever attained, is that of a concave surface - this being exactly what is to be expected of a surface that is truly level, since it is the nature of level surfaces to appear to rise to a level with the eye of the observer. This is ocular demonstration and proof that Earth is not a globe.
A flat planet (ours or any other planet) would be such an incredible observation that it would pretty much go against everything we know about how planets form and behave. It would not only change everything we know about planet formation, but also about star formation (our sun would have to behave quite differently to accommodate the flat-earth theory) and what we know of speeds and movements in space (like planets' orbits and the effects of gravity). In short, we don’t just suspect that our planet is spherical. We know it.
105) Aquarius and Libra can be seen from 65 degrees North to 90 degrees South! The constellation Virgo is visible from 80 degrees North down to 80 degrees South, and Orion can be seen from 85 degrees North all the way to 75 degrees South latitude! These are all only possible because the “hemispheres” are not spheres at all but concentric circles of latitude extending outwards from the central North Pole with the stars rotating over and around.

The Astronomer Royal, of England, George B. Airy, in his celebrated work on Astronomy, the "Ipswich Lectures," says - "Jupiter is a large planet that turns on his axis, and why do not we turn?" Of course, the common sense reply is: Because the Earth is not a planet! When, therefore, an astronomer royal puts words into our mouth wherewith we may overthrow the supposed planetary nature of the Earth, we have not far to go to pick up a proof that Earth is not a globe.

The evidence for a flat earth is derived from many different facets of science and philosophy. The simplest is by relying on ones own senses to discern the true nature of the world around us. The world looks flat, the bottoms of clouds are flat, the movement of the Sun; these are all examples of your senses telling you that we do not live on a spherical heliocentric world. This is using what's called an empirical approach, or an approach that relies on information from your senses. Alternatively, when using Descartes' method of Cartesian doubt to skeptically view the world around us, one quickly finds that the notion of a spherical world is the theory which has the burden of proof and not flat earth theory.
The Sun and Moon may often be seen high in the heavens at the same time - the Sun rising in the east and the Moon setting in the west - the Sun's light positively putting the Moon's light out by sheer contrast! If the Newtonian theory were correct, and the moon had her light from the Sun, she ought to be getting more of it when face to face with that luminary - if it were possible for a sphere to act as a reflector all over its face! But as the Moon's light pales before the rising Sun, it is a proof that the theory fails; and is gives us a proof that the Earth is not a globe.
77.) "Oh, but if the Earth is a plane, we could go to the edge and tumble over!" is a very common assertion. This is a conclusion that is formed too hastily, and facts overthrow it. The Earth certainly is, what man by his observation finds it to be, and what Mr. Proctor himself says it "seems" to be. flat – and we cannot cross the icy barrier which surrounds it. This is a complete answer to the objection, and, of course, a proof that Earth is not a globe.
I as well have come to grips with this reality that, not only do we live on a flat planet but we do indeed live in a dome environment. Everything that has ever been told to us has been a lie, just think about it the moon walk was faked, Nasa is a joke. (They) being the government's have lied to us since our existence to cover it all up, they have sent nukes up to try and break thru the roof of it but it will not happen. If you believe in the bible then you should know about the firmament. We live in the Truman show and I for one desire to know what is out there for us as a collective planet earth is a mere vessel we as a species are meant for more and our governments will do everything they can to keep us in the dark that is a fact and has been proven.

20. The common sense of man tells him - if nothing else told him - that there is an "up" and a "down" in -nature, even as regards the heavens and the earth; but the theory of modern astronomers necessitates the conclusion that there is not: therefore, 'the theory of the astronomers is opposed to common sense - yes, and to inspiration - and this is a common sense proof that the Earth is not a globe

Newtonian philosophers teach us that the Moon goes round: the Earth from west to east. But observation - man's most certain mode of gaining knowledge - shows us that the Moon never ceases to move in the opposite direction - from east to west. Since, then, we know that nothing can possibly move in two, opposite directions at the same time, it is a proof that the thing is a big blunder; and, in short, it is a proof that the Earth is not a globe.
25.) The surveyor's plans in relation to the laying of the first Atlantic Telegraph cable, show that in 1665 miles – from Valentia, Ireland, to St . John's, Newfoundland – the surface of the Atlantic Ocean is a LEVEL surface – not the astronomers' "level," either! The authoritative drawings, published at the time, are a standing evidence of the fact, and form a practical proof that Earth is not a globe.