Flat Earth theories get a smackdown courtesy of astrophysics
The universe is full of strange and bizarre things. The flat-Earth isn’t one of them. While many hypotheses have been proposed to explain the formation of our Earth, its place in the cosmos, and how it relates to the grander scheme of life and happiness, we know for a fact that the Earth isn’t flat. In fact, this is a such a rudimentary piece of knowledge that debating it isn’t really worth anyone’s time. Regardless, what follows is a little on why the flat-Earth theory falls flat.
1. The flat Earth model
The main thing the flat Earthers believe—which should be obvious—is that the Earth is flat. So unlike the globes and depictions of Earth most of us have grown to love, the Earth is a flat, boring disk. This disk has many features, according to the flat Earthers, that make it a plausible theory of cosmological significance. These range from the astronomical to the teleological.
The universe is ours, they proclaim, and the astronomers and other nasty scientists are just trying to trick us into feeling small and powerless. All of science and philosophy from the time of Plato forward, then, is just a complicated ruse formulated by the tyrants of NASA and the like to keep us feeling insignificant.
2. Antarctic mischief
How do the oceans stay land-bound on this flat-shaped disk, you ask? Couldn’t they just pour themselves into whatever lies beyond? Well, according to the flat-Earthers, the Antarctic (instead of laying in the southern hemisphere) encircles the disk, holding all the Earth’s vast oceans within a vast ice wall. But how has this giant ice wall eluded everyone on planet flat-Earth?
Surely, if we have airplanes, submarines, boats, and even space shuttle, we should have seen this Antarctic edge by now. But no, the flat-Earthers proclaim. NASA and other governmental agencies have been hiding the truth through coercion and intimidation. What they do, according to the flat-Earthers, is guard the edge of the Earth, protecting this secret.
3. Knowledge in a flat Earth world
The concept of a flat Earth conflicts with pretty much every known fact we’ve accumulated since the scientific revolution (and even before, come to think of it). The disciplines it transgresses range from astronomy, physics, and cosmology to geology, biology, and yes, even communications and dance therapy.
These flat-Earthers challenge everything from the scientific explanation of gravity to the known mechanics of the Sun. Scientists are liars, they say, and ultimately work to keep humanity in the dark. Considering the staggering number of people who’ve received scientific training, worked with scientists, and have friends who are scientists, this statement is really just amusing.
4. Flat Earth, flat roads?
One of the weirder “proofs” the flat-Earthers give for their beliefs are that roads are flat. How can that be if they have to account for the Earth’s curvature, they say? Well, this proof is wrong for several reasons. First off, most roads don’t travel along a straight path—they have to navigate mountain ranges, bumps and hills, and all sorts of other roadblocky-type things.
Secondly, however, some roads do in fact take the curvature of the road into account. When you have to travel a particularly straight stretch of land, for instance, you can rest assured that the engineers that built that stretch had some round-Earth foresight. And this foresight included an accounting of the Earth’s curvature.
5. Shifting constellations
One disproof—if you even need one—of the flat-Earth hypothesis is the shifting nature of the constellations around the globe. While it’s not necessarily fruitful to debunk their claims (they don’t really deserve attention), I will go on to articulate a few. The constellations are one, and we’ll approach a few more momentarily.
If the Earth was flat, moving from one side to the other wouldn’t reveal what it does: a different set of constellations. But under the Earth-is-round model (which feels a little ridiculous to say), it makes total sense. If you walk around to another hemisphere, you will navigate around the globe to the other side, see some different constellations, and feel great.
6. Eclipses and all that jazz
Eclipses are another sad fact for the flat-Earther. Since Aristotle’s time, people have known that they reveal the Earth to be spherical. To clarify, as the Earth moves between the Sun and the Moon, it slowly projects the Earth’s shape onto the Moon. As this move happens, we see just how round the Earth really is. Spoiler alert: it’s pretty darn round.
These eclipses show what we all really know—the Earth is a sphere. While flat-Earthers have tried to debate this fact (why?), it remains an obvious and damning critique. However, convincing the conspiracy-tainted mind is a task that’s beyond the scope of most of people’s talents.
7. A moving disk
Another common retort of the flat-Earther is that if the Earth were spinning in the way that it most certainly does, we would all spin off and die. Well, no. In a closed environment with an atmosphere and a whole lot of gravity, we would not fly off. Nevertheless, flat-Earthers persist.
And, alternatively to gravity, they have proposed their own baffling model to explain our terrestrial-bound nature. This disk that we apparently all exist on is moving up at a pace of 32 miles per hour. Seriously. If this doesn’t make you laugh, I don’t know what will. Anyways, how this disk moves like this, why, and what causes it is beyond me (probably beyond them, too).
8. Pictures from space
You would think definitive evidence of the Earth’s round nature would come from pictures taken from space. Astronauts, for instance, trying to show the world how cool it is to be in space, will take pictures from the international space station, say, send them to us Earthlings, and show us the round ol’ Earth. Alas, the suspicious flat-Earthers claim foul.
Since they believe most scientists to be liars in the midst of a massive and wildly implausible scheme, these pictures aren’t compelling. And if that’s the way they want to play it, fine. The rest of will just move on while they live in their flabbergastingly small (and flat) world.
9. Ships beyond the sea
Another clear reason the Earth isn’t flat is the fact that ships disappear beyond the horizon. On the flat-Earth theory, this doesn’t really make sense. Instead, you would expect to see the ship indefinitely. You would also expect to see islands, distant mountains, and other bodies of land that exist in faraway places. This clearly isn’t what we see.
Flat-Earthers have chalked this up to a failure of human vision—not the descension of the ship down the curvature of the Earth. Unfortunately for the flat-Earther, such an explanation doesn’t jive with anything we know about the neuroscience of the eye and the rods and cones within it. But, since the flat-Earthers clearly aren’t too keen on science, this doesn’t really matter to them.
10. Heights are helpful
Another fact that the flat-Earther should find disconcerting is that, like the ships disappearing beyond the horizon, you can see more as you go up in the atmosphere. On the flat-Earth hypothesis, this doesn’t make sense. But on the Earth-is-curved hypothesis, it does: the higher you stand up, the more beyond the curve you should see.
This fact makes absolute sense when you consider how spherical the Earth is. It doesn’t, though, make sense if the Earth is flat. And so, either you should disregard one of the simplest facts about the existence of this Earth, or close your eyes and ears to the faces of reality and conform to conspiracy.
11. Planes, trains, and cross-continental travel
If the Earth were flat, you wouldn’t expect travel from South America to Australia possible–it would, in other words, entail travel from one side of the earthy disk to the other. And, needless to say, under the flat-Earth hypothesis this wouldn’t be possible. Thankfully, the Earth isn’t flat and you could, if so inclined, fly from any place on the globe to any other.
But flat-Earthers think that because certain flights aren’t popular routes for airplanes and the like, that this means their covering for some sort of flat-Earthly conspiracy. Most people, however, are fortunate enough to see through this terrible piece of non-evidence—especially given that many of these flights have in fact been made.
12. Gravity on a disk
Another little fact that makes the flat Earth hypothesis implausible is the way gravity works with large bodies of mass. In essence, the larger and more massive an object, the more gravity it has. The Earth, then, which is relatively quite big, has a decent chunk of gravity. This gravity is so much that it pulls from all sides equally, creating a sphere.
On a disk, this is not how gravity would work. Instead, it would pull you more strongly at this center. The farther toward the periphery of the disk you move, then, the stronger the gravity would pull you toward the center. Since we don’t experience more gravity near the periphery of the disk, we know we’re not on a flat Earth.
13. The discovery of the spherical Earth
Because of eclipses and the Greeks’ proficiency with geometry, they had the Earth’s spherical nature figured out long ago. This fact was first discovered by Eratosthenes (276-194 BCE), a Greek philosopher and mathematician. What he found was that the Sun would cast a shadow with a different angle when at different parts of the Earth.
More specifically, he found that the shadow cast down a well in Syene (a city in Egypt) was more direct than a shadow cast at that same time of year in Alexandria, a town approximately 500 miles away. What this means is that the light is reflecting down on a curved Earth—straight on Syene and skewed on Alexandria.
Aristotle, another one of our ancient philosopher friends, noticed that the Earth was round through celestial observation. To do this, he looked to a place more close to home: the Moon. When the Earth passes between the moon and the sun, for instance, it creates a clearly circular shadow. If the Earth was a disk, this isn’t exactly what you would expect.
As I’m sure you’ve noticed from the different phases of the moon, the Earth isn’t flat. Instead, it’s a glorious and enticing sphere. If it were a disk, maybe it would look something like it does in this choice meme. Since it doesn’t, you can rest easy on your spherical Earth.
15. Ptolemy and the early Earth
The earliest models of the solar system, however, were more in line with the flat-Earth hypothesis than what came later. People thought the universe and all its contents revolved around us. But oh how wrong they were. These earlier models thought the rest of the solar system revolved around the Earth. These “geocentric” models, as they were called, were most compellingly articulated by the ancient astronomer, Ptolemy.
While he had to perform some trickery to explain the retrograde motion of some of the planets, he made a pretty compelling model for the time. It enabled fruitful predictions for calendars and other useful things. His model lasted for something like 1,300 years; it lasted until Copernicus and his predecessors came along.
16. The Copernican Revolution
In 1543, Copernicus published his “On the Revolutions of the Heavenly Bodies.” In it, he described a new model of the universe—one that would eventually become the one we hold today. This model, known as the “heliocentric” model, put the sun at the center of the solar system. This was a big shock to the religious community, which is why Copernicus didn’t publish it until he was on his deathbed.
The Copernican theory initially had some stifling problems. It still used some of the Ptolemaic trickery, for instance, so it wasn’t the best. Later, however, it was picked up by Galileo and turned into something that accurately depicted the structure of our solar system.
17. The birth of our solar system
Now that we’ve debunked some of the flat-Earth hypotheses and discussed a bit of the history behind astronomy, it’s time to get a grip on how the universe actually came to be. This understanding reveals why the planets are spheres and why nothing in the universe (except for maybe the occasional asteroid) is as flat as the flat-Earthers would want.
For the flat-Earth conspirators to be correct, they must claim that the entire 2,000 plus years of astronomical science we’ve discovered are an elaborate lie constructed by an elite class of malicious tricksters. Fortunately for us, this is not the case. Our solar system, as with all others, started with a nebula.
Each solar system (including our own) started with the formation of a sun. And these suns started with nebulae—large aggregations of gas and dirt. Over time these aggregations of celestial particles would slowly coalesce through gravity to become more and more dense. This would ultimately yield everything we’ve come to know and love—i.e., stars and planets.
These nebula are often composed of different particles. We can ascertain their composition, for instance, by the known color that these different particles emit. Hydrogen often comes in red, for instance, whereas elements like oxygen come off as blue. Most of the early nebulae, however, were only composed of hydrogen and helium, the fundamental elements of all stars.
19. The formation of a star
Stars are the first thing to form in any solar system. First, the gas and particles of a nebula aggregate to a point where they can form a dense and hot ball. This ball forms the nascent and developing beginnings of a star. This star then helps to organize the remainder of the particles in the nearby area, getting them to rotate in the same direction.
Once this process happens, gravity is set in place to organize the rest of the system such that planets can begin to form. This process happens in the same way that the star took. The remainder of the dust in the nebula, in other words, begins to aggregate into more dense balls of mass. These come from the protoplanetary disk.
20. The protoplanetary disk
The protoplanetary disk is what forms as a result of the new Sun in the solar system, and is exactly what it sounds like: a disk that will eventually go on to form the planets. This disk is the result of the new gravity enforced by this new and exciting sun. In essence, it warps spacetime such that the other clusters of elements can rally together further.
As this disk spins in the same direction, it begins to aggregate more and more particles. Some astronomers and cosmologists have compared this process to the formation of dust bunnies. At first, these balls of dust and other particulates are small and boring. But later they start to get a little more interesting.
21. More aggregation…
The clumps of celestial dirt and particles continue to aggregate until they form asteroid- and boulder-sized clumps. These balls, however, don’t have enough mass to form actual planets or spheres. Instead, most look like weird potatoes and other lame objects. For stuff to get more interesting, you’d have to wait until enough of these collide within the disk to get larger.
Eventually, some of these asteroid-like objects will begin to give us what we all came for: planets. While this process takes hundreds of millions of years, it does eventually happen. And this is how we end up with the beautiful solar systems we see around the universe.
22. Gravity and more gravity
As these rocks grow in size, they accumulate more gravity. And this gravity, in turn, causes more particles to aggregate around them. This cascade of celestial events causes the boulders and asteroid-sized objects only to grow larger. At this point in the formation of a solar system, you better look out: asteroids are flying from place to place, colliding and exploding.
While this point in a solar system’s life cycle is not at all conducive to life, it is necessary to produce life-friendly planets such as our own. Without this interstellar shooting gallery, we would not have planets with enough mass to grow as round and plump as they need to be.
Eventually, just like what happened with the Sun, these space rocks have accumulated enough mass to become planetesimals, earlier iterations of planets. These are essentially small planet cores that are spherical and fun-sized; they are spheres because of the way that gravity pulls at each end of the object.
Some of these planetesimals still exist in our solar system. Ceres, for instance, is a giant planet core that now resides in our solar system’s asteroid belt (which lies between Jupiter and Mars). It floats around all sad and lonely wishing to be a planet like ours. Unfortunately, the mechanisms that lead to planet formation have long since subsided in our solar system.
These early planets were the result of countless planetesimals colliding with each other. And this, in turn, was the result of different types of interactions between them. If the interaction was slow—i.e., a slow crash with little speed—the two would meld into one. If the crash was fast, on the other hand, the two would collide and explode into many smaller fragments.
These fragments would then aggregate again to start the whole process over again. Ultimately, the result of this relentless colliding and combining is a few solid, large planets that would dominate the rings of gravity around a star. And these, in turn, clean up the solar system to be the wonderful thing that they are.
25. Why planets are round
Planets are actually round because of the effects of gravity on bodies with enough mass. Once there’s enough mass, gravity pulls in with a lot of strength from each side at equal capacity. This causes the mass, whatever it is, to take on a spherical and beautifully round shape.
This is why planets and protoplanets and other large masses like stars take on a spherical shape—not that of a disk. So the flat-Earthers at this point deny the existence of gravity—a staggering retort, I know. But then again, these people are lost in their own world. Their own flat world, that is.
26. Asteroids and other non-round things
As mentioned earlier, some objects in the universe don’t have enough mass to produce enough gravity to take on a spherical shape. This is why asteroids mostly look like irregularly-shaped objects. This is a problem for prospective asteroid miners (a cool job in a new, surprising field) and the like who seek to harvest these asteroids of their inner goodness.
When asteroids do gain enough mass, they will pull themselves into a spherical shape. But until then, they will be as quirky as they are now. And this is more reason to discount the flat-Earth hypothesis. But there is more to our beautiful solar system than the shape of asteroids, planets, and stars.
27. Organization of the planets
During all of this planet and protoplanet formation, different process are changing how the planets form. For one, those planets closer to the Sun are too hot to maintain elements with low melting points (it’s too hot!). This is why they’re known as the rocky planets—they can’t maintain the gases and other elements that the planets farther away have.
When you move to the more distant parts of the solar system, you have planets surrounded by gases and ice. This is why they’re called, simply enough, the ice and gas giants. These planets (like Jupiter and Saturn) are surrounded by gases and other elements that the more inner planets can’t maintain.
28. Celestial pinball
During all this formation, the gravity of the many nascent planets can pull other planets from their orbit. The result is that many of these planets will collide, crushing and crashing into each other. This drastically reduces the number of planets in the solar system, and also cleans up the paths upon which these planets travel.
This is just another phase in the formation of a solar system. It’s this process that’s thought to be the birth of many moons (including our own). So without this process we wouldn’t have things like tides, full moon romances, and other fun celestial things.
Ultimately, the difference between these worldviews is a question of parsimony: which hypothesis best explains the data. The flat-Earth theory, in case you didn’t notice, doesn’t explain a single thing in the universe. It’s really embarrassing, actually, that some of my fellow species believe in something so ridiculously separated from reality.
There’s no real point in arguing against the flat-Earthers, then, because they don’t argue on the same grounds as those who accept empirical evidence. Similarly, there is absolutely no way such beliefs can become ascendant in our society—physics and science are too necessary for everything from smartphones to airplane travel.
30. A non-flat Earth
So, the Earth isn’t flat—it’s a sphere. And it’s on this beautiful sphere that we live, spend our days, fall in love, and go to work. While some—a small few, thank goodness—will try to tell you that the Earth is flat, you can just laugh it off. In fact, this is what I encourage you to do.
If there’s any sense in those who propose such nonsense, they will likely concede to your scientific rationale and maybe go brush up on some physics or astronomy. If not, then they will probably just dig their heels in and double down on the notion (if you can even believe that is possible). Anyways, the Earth is clearly a sphere. You’re welcome.