The horizon always appears perfectly flat 360 degrees around the observer regardless of altitude. All amateur balloon, rocket, plane and drone footage show a completely flat horizon over 20+ miles high. Only NASA and other government "space agencies" show curvature in their fake CGI photos/videos.
The horizon always rises to the eye level of the observer as altitude is gained, so you never have to look down to see it. If Earth were in fact a globe, no matter how large, as you ascended the horizon would stay fixed and the observer / camera would have to tilt looking down further and further to see it.
The natural physics of water is to find and maintain its level. If Earth were a giant sphere tilted, wobbling and hurdling through infinite space then truly flat, consistently level surfaces would not exist here. But since Earth is in fact an extended flat plane, this fundamental physical property of fluids finding and remaining level is consistent with experience and common sense.
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There never has been and there never will be any depiction of a Theodolite shooting a level line of sight from a promontory of even a few hundred feet toward the horizon which shows the horizon "rising to the level of the viewer" as flat-earthers keep chanting without any evidence.
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There never has been and there never will be an intelligible explanation for why the full moon faces with its sun-illuminated face toward the earth from high in the sky, from the flat-earth hypothesis which places the sun above a "flat" disc earth at nearly 90 degrees to the line of the moon's light as viewed from anywhere on planet earth.
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There never has been and there never will be any "flat" earth plausible geometry describing how a quarter moon makes the angle it does to the sun (while insisting it and the moon are some 3 thousand miles above the earth) twice each month for all to see.
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There never has been and there never will be any reasonable excuse for the fact that a ship or plane traveling due east (or due west) along the equator does not have to turn right (starboard) or left (port) in order to remain on the equator and due east (or west as the case may be).
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There never has been and there never will be any "flat" earth demonstration of WHY two parallel courses once embarked will in due time collide with each other on the real earth, since they don't do that on the "flat" earth model.
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There never has been and there never will be any reasonable "flat" earth explanation for how any weighted object in a vacuum will consistently be pulled in a perpendicular direction from the horizon line regardless of where on the real earth the experiment is conducted.
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There never has been and there never will be an explanation for the numerous flights of aircraft that pass over or close to Antarctica and traverse a distance too short to be plotted on a "flat" earth model, when many pilots, co-pilots and navigators who routinely fly such courses have and will continue to attest.
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There never has been and there never will be any honest video showing the horizon unable to conceal distant objects beyond the curvature of the earth, even while the refraction of light through the water vapor above a body of water makes it appear otherwise, since the progressive foreshortening of such objects belies the distortion caused by the refraction.
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There never has been and there never will be a seagoing navigator using a sextant and sea charts who can accurately plot his course over a great distance overseas, when he presumes the earth is "flat."
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I can go on.............
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