Flat Earth - RationalWiki
Roads are flat!
A common trope in flat-Earther literature is that roads, canals, etc. are built flat — not taking into account the curvature of the Earth.[8]
Surveyors ignore curvature when surveying a project because the error from ignoring curvature is minuscule.
For a 1 mile baseline the drop will be 8 inches. The length of the hypotenuse of a right triangle with one leg of 5280 feet and the other leg of 8 inches is 5280.00004209 feet. The error is 0.013 millimeters.
This error is so small that if you built a road that went all the way around the Earth using one mile long baselines the total error in length would amount to 1.05 feet.
Construction projects built underground that require a straight path do take into account the curvature of the Earth such as Japan's Proton Accelerator Complex. [9][10]
[edit] Star trail photography proves that the Earth doesn't move!
Although flat Earth isn't necessarily geocentrist (as one can technically still adopt a heliocentric worldview while holding to a belief in a flat Earth), flat earthers almost always fall into that camp.
One particular claim is that long-duration star trail photographs do not show any movement of the stars other than that caused by the Earth's rotation, the flat earther's reasoning being that, if the Earth is moving so fast around the Sun, the stars should appear smudged. This claim is symptomatic of all flat earthers' false assumptions about the distance between us and celestial objects, or their inability or lack of willingness to perform basic math.
Assume a star trail photograph of the nearest star is taken for 12 hours on a 10,000 wide pixel camera. The Earth would travel about 1,287,000 km during that time. The nearest naked-eye visible star is Alpha Centauri, which is 4.34 light-years (41 trillion kilometers) away. The star would appear to move 0.018 pixels.
[edit] Where's the curvature?
A lot of flat-earthers attempt to disprove the globe model by using pictures taken from high above the earth with a flat horizon, thereby "proving" that the Earth is flat: After all, if the earth is round you should see the curvature of the Earth. In actuality, no matter where you are and how high you are on the surface of the Earth, the horizon does indeed look like a flat line no matter where you look: A curvature should appear if the Earth were cylindrical instead. Indeed, the fact that there even is a horizon to begin with should prove the Earth to be round by itself, since if the Earth were truly flat, then a sufficiently advanced telescope ought to be able to see all the way to the edge of the earth. But don't get started on that track in a debate, otherwise you're going to spend your whole afternoon talking about perspective, light refracting from air, the parallax effect, mirages or GoPro cameras, or how even something as basic as a video of a ship disappearing bottom-first beneath the horizon is supposedly faked.
[edit] Why are there no real photos of the earth?
One common argument used by flat earthers is that there are no real photos of the earth.
This is simply not true, there are many photos of the earth including photos which predate the equipment required to create fake images .[11]
[edit] Why did Neil DeGrasse Tyson say the earth was pear shaped?
This argument is used often by flat earthers to claim that NASA is lying. In fairness, calling the Earth pear-shaped is rather stupid, as it is very nearly a sphere—much closer in shape to a sphere (or even an apple) than a pear.
Technically speaking, the Earth is an oblate spheroid; the reason it appears perfectly spherical in most photos is because the difference is very small (less than 1%). [12] additionally there are images that show the earth is not perfectly spherical [13]
[edit] Why don't rivers flow uphill?
A common argument used by flat earthers is that: if the earth was really spherical, rivers would have to flow uphill. No, really.[14]
In reality, "up" on a spherical planet where gravity is accounted for actually means "away from the core" — and due to gravity's effects on water, it actually flows downhill.[15]
[edit] Why is travel banned to Antarctica?
This argument is used by many flat earthers as "proof" that Antarctica surrounds the earth. [16]
In reality travel is not banned to Antarctica and there are commercial cruise ships that travel there.[17]