Interest in the notion that the earth is flat has been increasing in recent years. I have to say, as much of a jaded skeptic as I am, this level of self-deception is still amazing to me. It truly demonstrates that there is no practical limit to the power of motivated reasoning or the absurdity of conclusions which it can defend.

Serious flat earth proponents actually do believe that the earth is not a globe, but a flat disk. When you think about this for even a moment, many problems arise, but they have an answer to all of it. Not a good answer, but enough of one to allow motivated reasoning to take over.

Space Exploration

Perhaps the most obvious problem with belief in a flat earth is that we have been to space. You can actually see the earth as a spinning globe. There is no other viable interpretation of this direct and dramatic observational evidence. You might as well tell me that a basketball is not round.

This is what the flat earth wiki has to say about this challenge to their position:

The most commonly accepted explanation of this is that the space agencies of the world are involved in a conspiracy faking space travel and exploration. This likely began during the Cold War’s ‘Space Race’, in which the USSR and USA were obsessed with beating each other into space to the point that each faked their accomplishments in an attempt to keep pace with the other’s supposed achievements. Since the end of the Cold War, however, the conspiracy is most likely motivated by greed rather than political gains, and using only some of their funding to continue to fake space travel saves a lot of money to embezzle for themselves. In light of the above, please note that we are not suggesting that space agencies are aware that the earth is flat and actively covering the fact up. They depict the earth as being round simply because that is what they expect it to be.

The conspiracy theory, of course, is the last refuge of the hopelessly deluded. Any inconvenient evidence can be swept aside by making up a conspiracy theory ad hoc. What is the evidence for this alleged conspiracy? Zero. As they admit, this conspiracy would have to involve many nations in the world, not just the US and USSR/Russia. China, India, the UK, the European Union all have space agencies.

Why would the space agencies of all of these countries be engaged in the exact same conspiracy? You would think that, maybe, China would have noticed and called out the US for faking an entire space program.

This is the grand conspiracy of all grand conspiracies. Such conspiracies are untenable because they collapse under their own weight. You could never keep so many people in line for so long.

But we are just getting started deconstructing this extreme bit of nonsense. It is not as if the space program consists of faking only a few moon landings. The space program primarily consists of putting satellites into orbit. Satellites create the world-wide GPS system, monitor the weather, are used for spying, and establish our broadcasting and communication infrastructure. Google has mapped the world using satellite images.

Sorry, but NASA, the ESA, and other space agencies would have to be completely aware that physics and cosmology are dramatically different from what they think. All those satellites are in orbit, they follow orbital mechanics, and those orbits would not work if the earth were a disk instead of a spheroid.

Astronomy

The conspiracy would have to go way beyond just space agencies. Every astronomer in the world would have to be in on the conspiracy.

The first obvious problem they get into with physics and cosmology is that a disk shaped earth would collapse itself into a sphere due to its own gravity. No problem, say the flat earthers, we will simply get rid of gravity. It’s gone, it doesn’t exist.

“The earth isn’t pulled into a sphere because the force known as gravity doesn’t exist or at least exists in a greatly diminished form than is commonly taught. The earth is constantly accelerating up at a rate of 32 feet per second squared (or 9.8 meters per second squared). This constant acceleration causes what you think of as gravity.”

Problem solved. But wait – what about all those satellites? Being in orbit requires gravity. If the earth were just accelerating up wouldn’t they just come crashing down to the earth? But wait, this means the sun, moon, and actually the entire visible universe must also be accelerating together, in the same direction.

I have a telescope and I have used it to look at stuff. This makes me part of the vast conspiracy. I have seen Jupiter and its largest moons. You can see Jupiter as a spinning globe, showing a different face to us at different times. You can see the moons orbiting around Jupiter. Orbiting requires gravity.

The bottom line is that you cannot understand the universe without the notion of gravity. Galaxies are rotating, and they should fly apart unless they are being held together by their own gravity. We can calculate how much gravity would be needed, and in fact they need more gravity than what we observe, which lead to the theory of dark matter.

Gravity has also been directly measured in the lab, but those scientists must be part of the conspiracy also.

Earth’s Cycles

While your mind is reeling at the implications of this radical theory, you might consider the day-night and seasonal cycles of the earth. They have an answer for this as well.

“Day and night cycles are easily explained on a flat earth. The sun moves in circles around the North Pole. When it is over your head, it’s day. When it’s not, it’s night. The sun acts like a spotlight and shines downward as it moves.”

This just shows you how creative people can be. This is like Ptolmy’s epicycles – if you allow yourself the ability to rig the system with any new factors as needed, you can make anything sort-of work. The problems here are legion, the first of which is that the sun would be visible at all times from all parts of the earth. They try to dodge this obvious problem by saying the sun acts like a “spotlight.” This would have to make it invisible when the spotlight is not shining down on your part of the planet.

Their model also does not explain the phases of the moon. In their model the moon should be always full, if the “spotlight” sun shone on it, or always invisible, if it is in shadow (which is what they depict). There is no way to create the phases of the moon with their model. Don’t even get me started on lunar and solar eclipses.

They are also silent on what force keeps the moon and sun moving in circles around the disk of the earth. It’s not gravity. They have to invent a new force unknown to science to explain this. But they appear to have no problem making stuff up as needed.

Perhaps most amusing is how they brush off the apparent rising and setting of the sun. Previously they appeals to our direct senses to inform their conclusions:

“The simplest is by relying on ones own senses to discern the true nature of the world around us. The world looks flat, the bottoms of clouds are flat, the movement of the sun; these are all examples of your senses telling you that we do not live on a spherical heliocentric world.”

But now:

“Although the sun is at all times above the earth’s surface, it appears in the morning to ascend from the north-east to the noonday position, and thence to descend and disappear, or set, in the north-west. This phenomenon arises from the operation of a simple and everywhere visible law of perspective.”

Believe what you see, except when we tell you. Most people have probably seen a sunrise or sunset, especially over the ocean. This is not perspective, the sun is occluded over the horizon.

Air Travel

The airlines of the world would also have to be in on the spherical-earth conspiracy, and be willing to go to great lengths to maintain this conspiracy. Airlines carefully calculate the optimal path to take to get from point A to point B on what they think is a globe. This is important in order to save time and fuel, which is critical to their often thin profit margins. If the earth were a disk, their calculations would all be off.

This discrepancy would be greatest in the southern hemisphere. Imagine flying from the southern portion of South American to Australia. On a sphere this is a relatively short trip, just past Antartica. On a disk you would have to fly to the opposite end of the Earth. The discrepancy in travel time, and therefore fuel consumption, and even range of the aircraft, would be huge.

Problems with geography would be greatest on Antarctica itself. Currently there are research stations from 30 different countries spread throughout the continent. On a spherical earth all these stations would be fairly close to each other. On a flat disk, with Antacrtica spread around the outer edge, they would be extremely far away. All 30 countries would have noticed this massive discrepancy. The conspiracy grows.

Conclusion

I know I am just shooting fish in a barrel here. The notion of a flat earth is patently absurd and collapse even under the slightest scrutiny. It is fun, and can be informative, to deconstruct even a nonsensical scientific claim in detail.

But more interesting is the psychological phenomenon at work here. It is fascinating that people have the ability to twist logic and evidence to such a degree that they can maintain a belief that is at direct and obvious odds with reality. That is the real story here.

You might be tempted to argue that no one really believes this, but you would be wrong. I happen to personally know people who are flat earthers. Do a little digging yourself before dismissing this phenomenon.