So I’m reading this because I want to get a handle on what Flat Earthers actually believe. I didn’t get even a page into the guide before I found the first error. There is no mention of Eratosthenes (276-194 BC) the first person to calculate the circumference of the earth.

Mark Sargent seems to think globe earth go it’s start with the Copernicus model. This is incorrect. Sargent also fails to explain why the Copernicus model was proposed in the first place. It was an attempt at explaining the retrograde motion of the planets.

The rest of the opening chapter is hard to evaluate because there are no citations no nothing for me to actually check. Sargent is completely unfamiliar with the actual lines of evidence so doesn’t even address them.

Finally Chapter One: The Empty Theatre the argument here is that Hollywood hasn’t produced many moon movies. I wish I were kidding. For an opening argument this is not even close to compelling.

Chapter Two: Byrd Wall. In this chapter we learn about the fascinating potential of Antarctica and how the interior completely off limits. I know what you’re about to say: “didn’t a woman ski solo to the South Pole this year?”
Yes she did. The interior isn’t off limits.

Clue three: Mapmakers. Finally we are talking about the USGS. Nope sorry this isn’t about the USGS is about Azimuth Equidistant projection. This projection is not one I use. You can build the map from any point; distances in the azimuth direction will be correct.

But if you extend the map out too far everything gets extremely distorted. Mark Sargent is confused by this but really just math. When I deal with the USGS I mostly work with UTM. UTM is great on interprovincial level but if you extend it out everything gets distorted.

Map projections are an attempt to render 3D information as 2D. There are all approximations. The choice of which projection you use depends of your area of study. Why would we use a 1000 year old projection? So we can represent the poles properly.

Clue Four: Shell Beach this chapter makes the argument that most people wouldn’t even try to bust out of dome. True but some people would. Dark City, and the Truman Show are great movies but we are 4 clues in and there isn’t a single physical bit of evidence for flat earth.

I’m only four clues into Flat Earth clues and half the clues argue by evoking fiction. So far there is nothing for me to sink my teeth in. I want details, I want observations, tell me how the flat earth even works.

Clue Five: Status Quo. This chapter is a fictional journey into what could happen should people find out the earth is flat. I think this makes for interesting science fiction, but what it isn’t is a clue. We are now five “clues” in without a single data point. I’m frustrated.

Clue Six Depth Perception. FINALLY a model of the Flat Earth: a massive dome with LCD screens projecting the stars, sun, and moon. Fine. Let’s ignore gravity and do some thought experiments. First up: sun set and sun rise. They don’t work in this model.

If the sun is projected on a dome there is no place on earth that doesn’t have line of sight to the sun. All parts of the world experience would experience sun rise at the same time. This clearly doesn’t happen.

This problem is just magnified with the stars. The Southern Cross is never seen in the Northern Hemisphere. This makes sense on a globe. It doesn’t make sense with a flat earth as there’s nothing to block line of sight.

I’d be also curious as why nearby stars exhibit parallax. The LCD screen just happens to move stars to make it seem like a parallax shift. Well it true a advanced being could make a screen do anything, but unless you have some evidence this explanation just isn’t science.

We left gravity out of the model and now we will bring it back. The first thing it will do is try to crush everything into a sphere. Gravity is a radial force. The dome and earth could not be made of any known material. Nothing we have could prevent the disk from being crushed

If your model requires a substance that no one has ever seen you better have a damn good evidence. See Dark Matter. Since the Earth must be made on this material we should see it.

Let’s pretend we have the unbreakable earth and dome. The gravity felt by creatures on surface would be very different. Gravity of sphere basically behaves as if all mass was concentrated at the center. us on the surface all feel the pull toward that centre.

This radial symmetry is broken in a cylinder. Creatures walking around that surface would feel very different pulls of gravity depending on where they are on the disc. In fact in the center of the disk you should feel no force as the pull of mass surrounding you cancels out.

Not one of these very basic points is discussed in this chapter. What makes a model useful is the predictions it make. The Flat Earth model does make predictions as I tried to demonstrate. What we observe doesn’t match those predictions.