How do you know the Earth isn't flat?


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These people have invaded the comments sections of all my favourite rocketry and spaceflight Youtube channels. The moonhoaxers are bad enough, with their lack of knowledge about history, math, physics and logic worn on their sleeves, but the flat-Earthers are just all-round incompetents, adding ignorance of geography, geometry and even baser logic.

Some are just trolls, but some are poes, impossible to tell if they’re trolling for lulz or genuinely believe that we’d fall off a globe Earth. I despair.


Common Sense. Since Light travels in a straight line and I cannot stand on top of a mountain and see people in Japan looking back at me, (and I know Japan exists because I have been there) Logic dictates that it must be curved.



Well we have this awesome invention called the telephone and it has been around for over 100 years now. Since I have been on the other side of the planet and spoken to people on this side of the planet and it was day here and night where I was, then a few hours later I spoke to the very same people on the telephone and it was dark here and daytime where I was…Probably round.


Pure Anti-Chelonian propaganda!!


Because of the Foucault’s pendulum.


I’m wary of risking sanity by descending into flat earther territory online to find out their excuse for this one, but:

Where are the edges?
If the world is flat, either there’s physical edges or the world has an infinite surface area… Seeing as demonstrably neither are true, what’s their ‘reasoning’ around that one? :slight_smile:


Where are the edges?

A few years ago I stumbled into some flat earth videos on Youtube and I think their answer is that the edge of the disc of Earth is Antarctica. I mean, have YOU been there to confirm that there’s no edge? Given how restricted access is there, it’d be trivial to hide the edge. It’s probably the least difficult thing the Illuminati do.

It’s the same reasoning Ken Ham uses to disprove evolution: Did you see it happen? No? Case closed.


Just about all of science would be wrong if it was.


Um… NO! It’s four elephants on the BACK of one space turtle! Everyone knows that!


Flat Earth!

Note that “circumnavigating” the Earth is just walking in a circle around it. I like to imagine flat-earthers high-fiving each other when they figured out how circumnavigation works on a flat Earth.

Gus: We did it! Flat Earth can be circumnavigated!
Stan: But what about from North to South?
Gus: … Dammit Stan!


Yes, technically I don’t know that the Earth isn’t a hollow cylinder or something like that. But it’s obvious that the Earth curves, because distant objects fall away over the horizon. Also, if you go to the top of the mountain, you can actually see the Earth’s curvature.

In 240 BC, Eratosthenes not only knew the Earth was round* but calculated its radius to within a few percentage points of truth. In 2017… Teach The Controversy! ™

*technicaly, it’s an oblate spheroid.

What is your Band Name, Rapper Name, Album Name

Uni-Chelonian Heretic!


A bulged disc could explain the curvature that we see, though I’m not sure how they explain why the oceans don’t pool in a ring surrounding Antarctica.



My GPS still works.




The sun is a spotlight, apparently, according to these folks.

I’ve seen so many of their “proofs” in the last few weeks, it’s a wonder I can hold on to the last few shreds of my sanity.


TIL the Earth is a roulette wheel. Always bet on water.