Catalog of Flat Earth Claims & Refutations

I've tried to create a catalog of the major Flat Earth claims and their refutations, with links to supporting resources and data.  The links typically contain much more data and technical details about each subject.

Feel free to add more in the comments!

1. Earth Looks Flat
2. High-Altitude Footage Looks Flat
3. Earth Spin 1040 mph
4. Horizon always rises to "eye-level"
5. 8"  × miles squared should be hidden by curvature
6. Buildings should be tilted away from us
7. Sun rays prove the Sun is nearby
8. Zoom brings things back
9. Perspective & Vanishing Point explain why you can't see things
10. Gravity Doesn't Exist, it is Density!
11. Days should shift by 12 hours every 6 months
12. Thousands of Feet of Missing Curvature
13. Sun is Nearby
14. V2 Rocket Images Show Earth Is Flat
15. NASA Admitted Earth Is Flat
16. Airplanes would have to constantly pitch over
17. Attitude Indicator on planes
18. Gyroscopes prove the Earth isn't rotating
19. Water doesn't stick to a ball
20. Water always seeks level

MY SIMPLE QUESTION FOR FLAT EARTHERS

How does your horizon go from being in front of you to behind you and back, 360° around you - while also being "flat" in every direction?

FLAT EARTH CLAIM #1

"Earth is flat as far as we can tell"
"both models work, but the Flat Earth model works better".

Conclusion

FALSE

Rationale

This is a patently untrue statement. We can, in fact, know the Earth is round because it's very easy to show mathematically that it cannot be flat - and it doesn't require telescopes or NASA or government information...

We can see the horizon curvature by looking carefully at high-altitude footage AND CORRECTING AND TAKING INTO ACCOUNT ANY LENS DISTORTION.  In fact, the curvilinear nature of this lens makes it CERTAIN we are seeing actual curvature because below lens center any curvilinear distortion would be FLATTENING out the actual curvature which is why I have carefully choosen a frame where the horizon is below lens center.

Once you know it is round you can also use this data to calculate the circumference and know how large around it is. Turns out it is very large - which is why merely looking at the horizon doesn't make it obvious.

See How Al-Biruni Calculated the Circumference of the Earth Using a Mountain in the 11th Century

The angles of Polaris also rule out a flat plane.

See Flat Earth Follies: Polaris

And flight times and paths, especially in the Southern Hemisphere only work on a Globe

See Flat Earth Follies: Flight Times versus Airplane Speed - Globe Wins

FLAT EARTH CLAIM #2

"high altitude balloon footage shows it is flat"

Conclusion

FALSE

Rationale

The footage from high-altitude balloons with wide-angle curvilinear lenses shows the curvature fluctuating from CONCAVE (when the horizon line is below center)

To CONVEX (when the horizon line is above center)

When it is clear that the lens is having that much of an effect then it is entirely dishonest to point to ONE FRAME and say "look, it's flat!". If you study lenses you'll note that the distortion effect is the LEAST when the object passes through the exact center of the lens.

From this we can tell that when the horizon is below the center of the lens it tends to bow the horizon down, which would flatten out any visible curvature.

This is why we need to find the RIGHT image frame so that our analysis is not easily fooled.

The qualities to look for:

• Horizon is horizontal - not tilted at an angle
• The peak of the Horizon passes through dead-center and remains below center of the lens
• Needs to be taken from a high-altitude
• High-resolution image
• Wide Field Of View

That is why I selected this image to fully analyze and show that the amount of curvature shown in the horizon here matches what would be expected on a Globe (spoiler: it matches expected view).

See Flat Earth Follies: High Altitude Balloon footage PROVES Flat Earth

FLAT EARTH CLAIM #3

"we would fly off a spinning Earth going 1040 MPH"

Conclusion

FALSE

Rationale

Turns out, contrary to Flat Earther claims because they cannot do math apparently, that the effect is VERY small, just about 0.0339 m/s² -- or 0.345% the force of gravity itself.

We can tell we are spinning by weighing an object at the North Pole (or at very high latitudes) and at the Equator and noting this amount of change in the weight.  Things also weigh very slightly less at very high altitudes - the OPPOSITE effect one would expect if "density" was responsible but, in fact, buoyancy depends upon gravity to work.

See Flat Earth Follies: But you would fly off the Earth due to spinning

FLAT EARTH CLAIM #4

"the horizon rises up to eye level"

Conclusion

FALSE

Rationale

The horizon abosolutely does not "rise up" to "eye-level" or any other level.  It is trivial to demonstrate that it does exactly the opposite, it drops DOWN as you rise in altitude

I have personally tested this.

Here is my test showing that my application puts the recticle ON the horizon when I'm on the ground:

Here we find the horizon has fallen to ~2.8°



And at 38,800 feet it has fallen to ~3.4°

And in my full analysis I show that these are exactly the angles expected at these altitudes.

See Flat Earth Follies: The Horizon Always Rises To Eye Level

And this video I think puts the final nail in the Flat Earth "eye-level" coffin.  The best part of this is that this video was taken by a Flat Earther as his "proof" (a word they don't seem to comprehend).

FLAT EARTH CLAIM #5

"we expect 8 inches per mile squared to be hidden by the curvature"

Conclusion

MOSTLY FALSE

Rationale

This claim is only partially true if you submerged your eye (or the camera) half-way below "ground level" so that it's height was truly zero.

The 8" × miles squared formula is only an approximation for the amount of DROP due to curvature and is only semi-accurate over the first 100 miles.

So while it is TRUE that at 6 miles the DROP is 288 inches (24 feet), it is NOT the case that 24 feet of a distant object should be hidden by the Earth's curvature.  For an observer that is 5 foot 6 inches only about 78 inches would be hidden.

See Flat Earth Follies: How to derive 8" per mile squared and why it's wrong

FLAT EARTH CLAIM #6

"we should see the buildings tilting away from us"

Conclusion

MOSTLY FALSE

Rationale

At 35 miles away the tilt angle for a distant building would be one HALF a degree (0.5°).  That is far too small to detect at 35 miles away, you would be hard pressed to detect a building tilted at 0.5° up close.

So the buildings DO tilt away in all directions - but it's far too slight to be measurable by merely looking at it.

FLAT EARTH CLAIM #7

"Sun rays prove the sun is nearby and above the clouds"

Conclusion

FALSE

Rationale

This doesn't prove the Sun is undergound (bonus points to any Flat Earther who can identify what this image actually represents):

These rays are modeled in SketchUp and are absolutely parallel, they APPEAR to converge due to the effects of Perspective.

See Flat Earth Follies: Crepuscular rays

FLAT EARTH CLAIM #8

"Zoom brings things back, they never actually go over the horizon"

Conclusion

FALSE

Rationale

You can see this extreme amount of zoom doesn't change how much of the bottom of the buildings are hidden by the horizon.

See Flat Earth Follies: Optical Zoom is MAGICAL!

FLAT EARTH CLAIM #9

"Perspective and Vanishing Point explain why you can't see things"

Conclusion

FALSE

Rationale

First of all 'vanishing point' is an imaginary point at which parallel lines would appear to converge if extended to infinity - imaginary and appear being key words here.  There is zero evidence this is an actual point or distance away at which anything magically 'vanishes'.  So that's just inane.

Perspective is simply the fact that things get smaller with distance as modeled in this relationship: apparent size = actual size / distance

This doesn't give Perspective the ability to makes things disappear over a horizon - the whole object would be UNIFORMLY smaller.  This is not what is observed as we showed above with Zoom.

Zoom only enlarges things too small to see otherwise, it doesn't UNHIDE one thing when it's behind another because it doesn't change YOUR perspective.

See Flat Earth Failures: Perspective and Vanishing Point

FLAT EARTH CLAIM #10

"Gravity doesn't exist, things just sort by density"

Conclusion

FALSE

Rationale

In fact, the very action of buoyancy being appealed to REQUIRES gravity in order to operate.

Indeed, the formula for knowing the buoyant force on an object is B = p V g - where g is gravity.

And if you remove gravity by falling with it so there is no net acceleration then buoyancy disappears as shown very clearly in this video:

FLAT EARTH CLAIM #11

"The Days should Shift 12 hours between Summer and Winter"

Conclusion

THEY DO

Rationale

I had to literally laugh out loud at this one.

The days do shift around, every day.  One true rotation of the Earth is called a Sidereal day and is slightly less than 24 hours - one Solar Day which is noon to noon and keeps the Sun high in the sky at noon is called a Synodic day and is 24 hours long.  So each 24 hour period already accounts for our motion around the Sun.   This is why the stars "shift" relative to midnight-to-midnight -- we've gone more than a full rotation by the next midnight.

See Flat Earth Follies: Why Don't The Days Shift By 12 Hours Between Summer and Winter?

We can also OBSERVE the motion of the nearest stars such as Barnard's star. We SEE THAT STAR move very slowly against the background of other stars. For the nearest few hundred stars we've observed their proper and parallax motions.

All the stars move, but most move very very slowly.

FLAT EARTH CLAIM #12

"Thousands of feet of 'missing' curvature"

Conclusion

FALSE

Rationale

I've looked at numerous of these claims - they usually have several common errors:

• They OVER ESTIMATE the actual distances
• They LIE about how much is clearly obscured
• They IGNORE the observer height

Fix those issues and you get down to measurement error and changes in refraction.

I've looked at:

Toronto CN Tower from Olcott, NY - explained

and

Chicago skyline 'looming' from MI - explained

In the most detail.

But also mountains:

Flat Earth Follies: The Incredible Shrinking Mountain

Flat Earth Follies: Mount Diablo from Loomis CA <<  25 miles of error on the distance!

FLAT EARTH CLAIM #13

"The Sun is nearby"

Conclusion

FALSE

Rationale

Why a nearby sun is impossible.

FLAT EARTH CLAIM #14

"V2 Rocket Images show the Earth is Flat"

Conclusion

FALSE

Rationale

You didn't check them very carefully.

When you stitch them all together:

Amount of horizon curvature visible is a function of the camera Field Of View.

See V2 rocket footage from 1948
See Flat Earth Follies: High Altitude Balloon footage PROVES Flat Earth

FLAT EARTH CLAIM #15

"NASA Admitted the Earth is Flat"

Document Link: Derivation and Definition of a Linear Aircraft Model

Conclusion

FALSE

Rationale

That is a mathematical description of a very simplistic FLIGHT MODEL, that is all.

In fact, that model doesn't include an atmosphere either -- assumes no wind.  Does that mean wind doesn't exist?

It doesn't model the ground either.  Does ground not exist?

It doesn't model the effects of the craft on the atmosphere around it (no wingtip vortices, etc).  Does that mean these things don't exist?

Or does it just make these choices as SIMPLIFYING ASSUMPTIONS in order to remain comprehensible and useful to the purpose for which the work was done (which it says is for 'quick approximations and desk calculations').

You know what it DOES include?

Gravity.

Also, it's completely obsolete, nobody models flight dynamics that way now.

FLAT EARTH CLAIM #16

"Airplanes would have to constantly pitch down to fly over a globe!"

Conclusion

100% TRUE!

Rationale

Congratulations #FlatEarth you finally got one right!  (the general claim, this meme is nonsense)

However, as per usual, you didn't do the calculations to see what RATE you would have to 'pitch over'.

You see, the curvature 'drop' is BUILT INTO the flight dynamics - the plane isn't flying a linear path and having to drop down, it is flying along the curve.

The pitch rate to compensate for the curvature at 85,000' for a craft going 2194 mph is:

(360/(2*pi*(3959+(85000/5280))))*(2194)/60 = ~0.527° per minute (~0.00878°/sec)

Still only a very slight rotation that wouldn't be specifically noticeable and would very easily be compensated for in pitch rate - in this case, by the computer that is actually flying the airplane. But the computer doesn't even have to understand the Earth curvature to do this, it just needs to keep Vertical Speed (VS) near zero which is determined by pitch rate and power settings.

YOU DO NOT HAVE TO KEEP ADJUSTING FOR THE CURVATURE - THE RATE OF CURVATURE IS NEAR CONSTANT.

Read the article for how airplanes actually adjust pitch rate and why it matters not:

See Flat Earth Follies: Planes would have to constantly pitch down to fly!

FLAT EARTH CLAIM #17

"The Attitude Indicator on planes proves the Earth isn't curved because they don't pitch over!"

Conclusion

TRUE... LOL just kidding... COMPLETE LOAD OF BOLLOCKS

Rationale

At some point in this list you just come to the conclusion that #FlatEarth folks don't do their research very honestly.

This video shows how the Pendulous Vanes on the bottom of the Attitude Indicator are used to constantly keep it aligned with GRAVITY.

See Flat Earth Follies: Planes would have to constantly pitch down to fly!

FLAT EARTH CLAIM #18

"Gyroscopes prove the Earth isn't rotating"

Conclusion

FALSE

Rationale

Aww sweetheart, your little piece of junk toy gyroscope isn't a precision instrument, regardless of what the salesperson told you.

I'm sorry you wasted $100 on a piece of junk but hey, gyroscopes are fun to play with!

Here is a real gyrocompass finding North using the spin of the Earth:

And here is a Flat Earther video that explains what you need to test it properly (hint: a 55 pound gyroscope and a nearly frictionless environment):

See Flat Earth Follies: Planes would have to constantly pitch down to fly!

FLAT EARTH CLAIM #19

"Water doesn't stick to a ball"

Conclusion

FALSE

Rationale

Doesn't even need a ball, water will naturally form a spheroid in the absence of other forces:

There are numerous forces that CAN make water stick to a ball:

• van der Waals forces (between molecules)
• electro-static forces
• Gravity

In the case of the Earth, which has an enormous mass, it is Gravity that largely causes the sticking to the ball (adhesion and surface tension also play a microscopic role).

On a tennis ball it would be various adhesive forces such as van der Waals and capillary forces precisely because the tennis ball is NOT massive.

So the only thing #FlatEarth'ers prove by spouting this is their ignorance of extremely basic physics.

But the tennis ball can only hold a small amount of water this way.  Can any Flat Earther explain why and calculate how much water the tennis ball would hold?  No?  I didn't think so.  Come back when you can and we can have an actual discussion.

Gravity is very weak compared to the electromagnetic force - however, the electromagnetic force is directional and can cancel itself out while Gravity is pulling in all directions and only adds up.  It is the fact that gravity cannot be directed, shielded, or cancelled out that distinguishes Gravity from the electromagnetic force.

Your ability to momentarily generate a sufficient moment to "jump" upwards -- before that directional force is reversed by Gravity and you fall back to the ground accelerated at 9.8 m/s^2 -- doesn't prove anything except what we already know -- that the electromagnetic force (stored as chemical and mechanical energy in your body) is pretty strong when you align a significant amount of it in the same direction.  When NOT aligned it is impotent (as in a chunk of metal with no current flowing and no magnetism).

I already showed in Flat Earth Claim #3 that the centrifugal acceleration is far smaller than gravity, so there is no physical issue with the Water related to Earth's spin either.

FLAT EARTH CLAIM #20

"Water always seeks a level"

Conclusion

TRUE!  Another #FlatEarth win!

Rationale

But again, there is just one little problem with that.

Flat Earthers don't know what the word Level means.

Specifically, in terms of the shape of the Earth, Level denotes a surface of equipotential Gravity.

The Geoid is that equipotential Gravity surface that coincides (in a least squares sense) with Mean Sea Level.

Can we put this to the test?  Well Peter Leane's test over 1530 meters shows the curvature pretty well.  It also shows the care that needs to go into measuring such an extremely slight curvature as exists on the Earth over the distances required to get a good measurement.

George Wallace also demonstrated this in the 1870's and showed that Rowbotham's error was not accounting for Refraction:

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Come back later for more!