# Best proof the earth isn't flat **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [October 10, 2026, 9:19pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737 "2026-10-10T21:19:17Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [October 11, 2026, 2:49pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/21 "2026-10-11T14:49:19Z")
The weird part is that other world is a sphere. Go figure. ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [October 11, 2026, 3:03pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/22 "2026-10-11T15:03:04Z")
> [@don\_t\_ask](#): > > If it was we could just go to the edge and sweep all our environmental waste underneath. Let’s go to the ~~quarry~~ edge of the world and throw stuff down there! ---
**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\ **Post date:** [October 11, 2026, 3:22pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/23 "2026-10-11T15:22:40Z")
I am a Member in Good Standing of the _Flatten The Earth Society._ We **don’t** believe the Earth is flat. That would be silly. The Earth is _not_ flat.  **NOT _YET_ !**  **Everybody come to the Civic Center on Saturday, and bring your shovels!** ---
**Author:** ![glee](https://avatars.discourse-cdn.com/v4/letter/g/b5a626/32.png) [@glee](https://boards.straightdope.com/u/glee)\ **Post date:** [October 11, 2026, 5:03pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/24 "2026-10-11T17:03:17Z")
If the Earth is flat, wouldn’t there be an edge in every direction? ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [October 11, 2026, 5:10pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/25 "2026-10-11T17:10:36Z")
> [@mbh](#): > > I see someone watched _Land of thet Lost_ when they were kids. _(Googles Land of the Lost)_ Hah, I _did!_ It’s not why I made my comment, but vague childhood recollections of scenes from that show have occasionally surfaced in my memory, but I could never recall the title. ---
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [October 11, 2026, 7:31pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/26 "2026-10-11T19:31:03Z")
> [@Elmer\_J.Fudd](#): > > But blind faith is usually a financial windfall for its leaders. Remarkably, the flat earthers have failed to monetize the gullibility of their followers. They should definitely book expensive cruises on cheap watercraft to the edge of the world and sink them once out of sight of land. Money + evidence of folks sailing off the edge of the world. Win, win. Some have. A lot of them have monetized YouTube channels with lots of followers. One sells a Flat Earth app. It has been know for ages that it is a security nightmare - passwords are in plaintext - and he has done nothing to fix it. One of the features is that you can see the distance between you and other flerfs. The code that computes this distance assumes a globe earth. The flat earther who went to Antarctica for The Final Experiment and was honest enough to admit he was wrong has taken a financial hit. And of course lots of flat earthers passed up a free trip to Antarctica to view the 24 hour sun. No gun-toting NASA penguins were seen. ---
**Author:** ![mbh](https://avatars.discourse-cdn.com/v4/letter/m/a6a055/32.png) [@mbh](https://boards.straightdope.com/u/mbh)\ **Post date:** [October 11, 2026, 7:40pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/27 "2026-10-11T19:40:51Z")
> [@Der\_Trihs](#): > > Hah, I _did!_ It’s not why I made my comment, but vague childhood recollections of scenes from that show have occasionally surfaced in my memory, but I could never recall the title. Well, I was referring to the Flat Earthers getting their cosmology from the show, but it’s good to bring back fond memories. ---
**Author:** ![crowmanyclouds](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crowmanyclouds/32/19884_2.png) [@crowmanyclouds](https://boards.straightdope.com/u/crowmanyclouds)\ **Post date:** [October 11, 2026, 8:09pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/28 "2026-10-11T20:09:57Z")
> [@Voyager](#): > > No gun-toting NASA penguins were seen. Where are the guns, Nathan? Where are the guns? ---
**Author:** ![burpo\_the\_wonder\_mutt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/burpo_the_wonder_mutt/32/365_2.png) [@burpo\_the\_wonder\_mutt](https://boards.straightdope.com/u/burpo_the_wonder_mutt)\ **Post date:** [October 11, 2026, 9:09pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/29 "2026-10-11T21:09:10Z")
What’s that, Cecil? > **[You say the earth is round? Prove it](https://www.straightdope.com/21341591/you-say-the-earth-is-round-prove-it)** ---
**Author:** ![Elendil\_s\_Heir](https://avatars.discourse-cdn.com/v4/letter/e/7cd45c/32.png) [@Elendil\_s\_Heir](https://boards.straightdope.com/u/Elendil_s_Heir)\ **Post date:** [October 12, 2026, 3:17am UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/30 "2026-10-12T03:17:22Z")
Lyndon Johnson liked to tell the story of a young, impoverished teacher, desperate for work during the Great Depression, who was interviewed for a job by a rural Texas school board. The interview went well until one board member drawled, “We have some people around here who believe that the Earth is flat, and some who believe it’s round. What do you think?” The teacher eagerly said, “I can teach it either way!” ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [October 12, 2026, 9:11am UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/31 "2026-10-12T09:11:41Z")
As I said upthread, there is no proof that will move a flerfer. They are impervious. IMO the “best” proof for a normie is that it’s impossible for a lump of rock and iron the mass of the Earth to be any shape other than very nearly spherical. The term of art here is **[Hydrostatic equilibrium → Planetary Geology - Wikipedia](https://en.wikipedia.org/wiki/Hydrostatic_equilibrium#Planetary_geology)**. If we ran Earth through a giant **[Dough Roller](https://doughrollermachine.com/)** to make it into the biggest damned rock pizza with iron lump topping you ever saw, and left it orbiting right here just like it is, in no time flat (heh 😉 ) it’ll have made itself into a sphere again. If it’s flat now, and has been flat for awhile what is keeping it flat? Only magic can do that. Google AI’s thoughts on making Earth into an 500 mile-thick pizza: > **Google AI** > > **Prompt:** If you squeezed all the material of the Earth into a disc 500 miles thick, how large would the disc’s diameter be? > > **Results:** > The disc’s diameter would be approximately **25,725 miles**. > > To find this, you calculate the total volume of the **Earth** using its average radius of about **3,959 miles** , which yields a volume of roughly **260 billion cubic miles**. If you reshape this exact same volume into a cylinder (disc) with a fixed thickness of **500 miles** , the resulting footprint requires a radius of **12,863 miles** , making the total diameter **25,725 miles** —slightly more than the Earth’s actual equator-to-equator diameter. Interesting coincidence to me that my arbitrary WAG of 500 miles yields a diameter very close to the Earth’s actual circumference. Numerologists might have a field day here. More fun w our new toys. Here’s Google AI’s thoughts on how long it would take for flat Earth to reform itself into a near-sphere: > **Google AI** > > **Prompt:** If we reformed the Earth into a disc 500 miles thick and roughly 13,000 miles in radius, without heating the materials above their current temperatures, roughly how long would it take for the material’s self-gravity to return the planet to hydrostatic equilibrium and a near-spherical shape? > > **Results:** > It would take only **minutes to hours** for the main catastrophic collapse to return the Earth to a near-spherical shape. > > The process is governed by the following stages and physical mechanisms: > > ## **1. Gravitational Stress vs. Rock Strength** > > The structural yield strength of solid rock is roughly 100 to 500 megapascals (MPa). Reshaping the Earth into a massive disc with a 13,000-mile radius and 500-mile thickness creates catastrophic gravitational stresses reaching tens of gigapascals (GPa) pulling toward the center of mass. Because this pressure is orders of magnitude greater than the mechanical strength of the material, the rock cannot maintain its shape. It will instantly experience planet-wide brittle fracturing and rapid plastic failure. [1, 2] > > ## **2. The Dynamic Collapse (Minutes to Hours)** > > Because the material’s strength is completely overwhelmed, it will behave like a hyper-dense fluid or a colossal granular avalanche rather than a rigid body. [2, 3] > > - The fundamental **free-fall timescale** (_tff_) for an object of Earth’s average density is roughly **15 to 20 minutes**. > - Due to internal friction, viscosity, and shear resistance of the cold materials, the collapse will be slowed down slightly from a pure free fall, but it will still proceed as a rapid, violent implosion taking anywhere from a few minutes to several hours to bunch back together. [2] > > ## **3. Achieving True Equilibrium (Weeks to Months)** > > While the planet will become roughly spherical within hours, it will not instantly be in a peaceful hydrostatic equilibrium. The kinetic energy released by this collapse will be staggering—the friction and compression would generate enough heat to melt the planet entirely, turning it into a magma ocean. The Earth would “ring” with massive seismic shockwaves, and it would take weeks or months for the molten mass to fluidly adjust, damp out the kinetic energy, and settle into a smooth, stable oblate spheroid. [2, 4, 5] > > If you are designing a sci-fi world or a physics simulation, let me know if you want to explore **how much thermal energy** this collapse releases or what the **resulting gravitational field** would look like before the collapse begins! > > [1] [https://www.quora.com](https://www.quora.com/Assuming-the-earth-was-a-flat-disc-floating-in-space-how-long-would-it-take-gravity-to-reshape-it-into-a-spherical-globe) > > [2] [https://www.facebook.com](https://www.facebook.com/groups/648677616005071/posts/1871758363696984/) > > [3] [https://www.quora.com](https://www.quora.com/If-you-cut-off-a-half-of-Earth-how-long-will-it-take-for-the-remainder-to-become-spherical-again) > > [4] [https://www.quora.com](https://www.quora.com/How-long-does-it-take-for-gravity-to-shape-planets-into-spheres) > > [5] [https://www.youtube.com](https://www.youtube.com/watch?v=NYggpFIU180) TLDR: it won’t take long. Somebody ought to mention this to Randall Munroe; I sense a potential What-If article here. The consequences for the biosphere of either the flattening or the re-sphering are left as an exercise for the reader. 🤪 ---
**Author:** ![purplehorseshoe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/purplehorseshoe/32/2996_2.png) [@purplehorseshoe](https://boards.straightdope.com/u/purplehorseshoe)\ **Post date:** [October 12, 2026, 9:27am UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/32 "2026-10-12T09:27:16Z")
> [@LSLGuy](#): > > ran Earth through a giant **[Dough Roller](https://doughrollermachine.com/)** to make it into the biggest damned rock pizza with iron lump topping you ever saw “I’m sorry, sir, our biggest is a 16 inch, and ah, we’re fresh out of iron lumps, is pepperoni okay instead?” ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [October 12, 2026, 9:51am UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/33 "2026-10-12T09:51:58Z")
Hee hee. I picked my 500 miles thickness to approximate the proportions of a 12" diameter thick crust pizza dough round before toppings & cooking. Mine’ll even be self-cooking. 🤪 ---
**Author:** ![burpo\_the\_wonder\_mutt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/burpo_the_wonder_mutt/32/365_2.png) [@burpo\_the\_wonder\_mutt](https://boards.straightdope.com/u/burpo_the_wonder_mutt)\ **Post date:** [October 12, 2026, 12:56pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/34 "2026-10-12T12:56:10Z")
I’m really hankering for a slice of Earth right about now. ---
**Author:** ![Gyrate](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gyrate/32/3588_2.png) [@Gyrate](https://boards.straightdope.com/u/Gyrate)\ **Post date:** [October 12, 2026, 1:08pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/35 "2026-10-12T13:08:12Z")
> [@Exapno\_Mapcase](#): > > The earth can’t be flat because turtles don’t exist. I thought it was birds that didn’t exist? ---
**Author:** ![solost](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/solost/32/11776_2.png) [@solost](https://boards.straightdope.com/u/solost)\ **Post date:** [October 12, 2026, 1:18pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/36 "2026-10-12T13:18:49Z")
There’s no proving the Earth is round to flat Earthers. I watched a documentary about the flat Earther community called _Behind the Curve_ (it used to be on Netflix, but now I think it’s only available on some free channel like Tubi). It does a good job exploring the mindset. In BtC, a flat Earther bought a digital gyroscope for $20k of his own hard-earned money, that was supposed to give a certain reading if the Earth was actually round and revolving. They expected it _ **not** _ to give that reading, and thus prove the Earth is flat. It did give the reading. So they said the device was being affected by the Sun’s rays, and it needed to be sealed in a box made of magnesium to give a ‘proper’ reading. Then they did an experiment where they aimed a laser from one telephone pole to another (X) distance away. If the Earth was flat, it would hit at one spot, but if the Earth was round, it would hit at a higher spot. It hit at the higher spot. So they explained that away somehow, the details of which I forget. So they just keep moving the goalposts. I get the impression that flat Earthers feel like they’re underappreciated or underestimated by others, and believing that the Earth if flat is a way for them to feel like they’re privy to ‘insider knowledge’ about the world and thus feel superior to us ‘globies’. They are also a very paranoid crowd. The main character in the BtC doc, a guy named Mark, was sort of the de facto leader of the flat Earthers, but once he started getting too much attention from the media, including the filming of the BtC doc, the rest of the FE community started turning on him, accusing him of being a ‘government plant’ to keep an eye on them. > [@P-man](#): > > If it were flat, don’t you think people who lived near the edge would be charging a mint to come and look over the edge? The edge is surrounded by insurmountable ice cliffs, duh. _Everybody_ knows _that_ 😄 ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [October 12, 2026, 1:27pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/37 "2026-10-12T13:27:53Z")
Am I the only one here disturbed by the fact that members here know anything at all about a “flat-Earth community”? To the point some people seem to know what they “believe”? You watched a _documentary_ about it, giving it even that much attention? ---
**Author:** ![solost](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/solost/32/11776_2.png) [@solost](https://boards.straightdope.com/u/solost)\ **Post date:** [October 12, 2026, 1:35pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/38 "2026-10-12T13:35:07Z")
I find the capacity for humans to convince themselves of false facts to be interesting, and I think it illuminates much about the mindset of people who believe political ideologies that are harmful to them are actually beneficial, or people with fundamentalist religious beliefs. I think to better understand our capacity to fool ourselves is to help inoculate us against falling victim to it. ---
**Author:** ![burpo\_the\_wonder\_mutt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/burpo_the_wonder_mutt/32/365_2.png) [@burpo\_the\_wonder\_mutt](https://boards.straightdope.com/u/burpo_the_wonder_mutt)\ **Post date:** [October 12, 2026, 1:37pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/39 "2026-10-12T13:37:13Z")
Know thy enemy. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [October 12, 2026, 1:47pm UTC](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737/40 "2026-10-12T13:47:19Z")
As current events conclusively prove, CTs + misplaced faith = a very dangerous global phenomenon. IME flat earth was one of the first CT’s to go big time and back then was totally a joking matter. Others, e.g. JFK or Moon landing, had serious real world implications. Flerf? Hah hash; it is to laugh. You could almost say it’s the SNL parody of CTs. Except it’s now become very real. By its age and by its wackiness, it’s been more studied and more written about. And for longer. I’d sure not take up trawling through the primary sources for any 2020s era CTs: too much grift and evil. But something from the oh-so-innocent 1970s? Why not? Or so the thinking goes. IMO YMMV etc. [Previous page](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737.md?page=1) [Next page](https://boards.straightdope.com/t/best-proof-the-earth-isnt-flat/1033737.md?page=3)