Humans first went to the Moon in Apollo missions. To some, the feat seems so farfetched they would rather believe the false notion it was filmed on Earth. To make an in-joke out of it, some films & other media featured the conspiracy theory as a parody.

Flat-Earthers and other believers of the moon hoax conspiracy theory naturally cannot realize that they are being featured as objects of a joke. These parodies spread in their communities as though they are “proof” or “endorsements” of their false belief.

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Atmospheric Duct

An atmospheric duct is a horizontal layer in the lower atmosphere in which a thermal inversion causes light rays to be trapped and continuously guided near Earth’s surface. They tend to follow Earth’s curvature without escaping to space.

Water heats up slower than air and will be cooler than air most of the time. In turn, the colder water cools down the layer of air just above it, creating a thermal inversion that can form a duct.

It is the reason flat-Earthers like to perform observations from very close to the water’s surface. It will be easier for light to bend, revealing objects that are geometrically behind the curvature. Then, they will incorrectly attribute it to “the lack of curvature.”

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Digital Scans of Images From the Apollo Missions

Before 2009, Apollo missions images that we saw were scanned from the secondary copies that NASA distributed to research facilities after each mission. Only in 2009 NASA made high-resolution scans from the original films & made them available to the public.

Today, we can still find the older scan results. Flat-Earthers like to find defects in these low-quality scans & use the fact as “evidence” they are just paintings. In reality, they are scanned from the printed photos, which can preserve the texture of the photo paper itself.

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Hafele–Keating Experiment

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The Hafele–Keating experiment was a test of time dilation. Four atomic clocks were flown around Earth, following and against Earth’s rotation, then compared to those remaining on the ground. The results were consistent with relativity.

The theory of relativity can be counterintuitive & difficult to understand. The Hafele–Keating experiment demonstrates a direct measurement of time dilation, a specific aspect of relativity, using a practical concept in our everyday lives.

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Conspiracy theorists, including flat-earthers, like to assign each letter in the alphabet a number, come up with a really creative way to get “666” out of a word, then associate the word with “evil.” In reality, it is just numerology and has no basis in reality.

The website shows us that we can always find a way to get “666” out of practically any word with more than a few letters, demonstrating the absurdity of this practice.

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Down Direction of a Globe

A globe is a scaled-down model of the spherical Earth. It can be used to explain the down direction on the real Earth, which is toward the center of the globe. Flat-Earthers like to confuse the down direction explained by the model with that of the real Earth. In reality, the down direction we experience is different from that explained by the globe, which is only a model of the actual Earth.

Rho Aquilae and Stellar Proper Motion

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Stars exhibit proper motion. They move relative to other stars in the sky, albeit very slowly. Due to its proper motion, in 1992, the star Rho Aquilae crossed the boundary of its original constellation, Aquila, to the neighboring Delphinus.

Constellations appear the same for years, and flat-Earthers wrongly use it as “evidence” stars are stationary. In reality, with precise measurements, we know the stars are moving.

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Pigeon Chess

“Pigeon chess” is a figure of speech & an Internet lexicon, referring to debates with science deniers like flat-Earthers. They are ignorant of the subject matter but standing on a dogmatic position that cannot be moved with any amount of education or logic but who always proclaims victory.

The term originates from an book review: “Debating creationists on the topic of evolution is rather like trying to play chess with a pigeon; it knocks the pieces over, craps on the board, and flies back to its flock to claim victory.”

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Karen Nyberg Green Screen Video Hoax

A video hoax spread in flat-Earth communities, incorrectly claiming the woman in the video is astronaut Karen Nyberg, supposedly in the process of faking microgravity in front of a green screen.

In reality, the woman in the video is Paige Windle, who made the video with a flat-Earther (also her partner), David Weiss. Weiss did attempt to correct it, but many flat-Earthers do not appear to be aware that Weiss was trying to say the woman is not Karen Nyberg, nor are they willing to accept being victims of a hoax.

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Curvature Analysis: Langkawi from Penang, Malaysia

General Information

  • Claimed by: David James (Facebook account)
  • Object 1:
    • Name: Gunung Raya, Langkawi
    • Distance: 68.2 miles / 109.76 km
    • Elevation: 2830 ft / 862.6 m
  • Object 2:
    • Name: Northwest Ridge of Langkawi
    • Distance: 74.5 miles / 119.9 km
    • Elevation: 2200 ft/ 670.6 m
  • Observer:
    • Location: Golden Sands Hotel, Penang, Malaysia
    • Elevation: 85 ft / 26 m

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Correct Hidden Formula

Flat-Earthers like to use the erroneous “8 inches per mile squared” to calculate the height hidden by Earth’s curvature. The following is the correct equation for the purpose, accounting for the observer’s height & atmospheric refraction

h_\mathrm{h} = { R \over \cos\left[ { s \over R } - \arccos\left( { R \over R + h_\mathrm{O} } \right) \right] } - R

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Refraction Effect on the Lake Pontchartrain Power Transmission Line

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The strength of atmospheric refraction is not constant but varies depending on the weather condition. As a result, a distant object usually obscured by Earth’s curvature can sometimes be visible if the refraction is strong enough.

Lake Pontchartrain transmission towers demonstrate Earth’s curvature. Flat-Earthers like to cherry-pick moments where the towers appear straight, ignoring other cases. In reality, they look straight only because the refraction was strong enough.

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Pic Gaspard

The photo of Pic Gaspard taken from Pic de Finestrelles is one of the farthest line-of-sight photos of an object on Earth’s surface, taken from another location on Earth’s surface. It is possible to take the photo due to the height of the peaks & atmospheric refraction.

The apparent height of Pic Gaspard relative to the other peaks proves Earth is a sphere. If Earth were flat, Pic Gaspard should appear higher than Grand Ferrand from the observer’s location. Simulations also give us the same results as observation, confirming that it is really what would look like on a spherical Earth.

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Dip Circle

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Earth’s magnetic field does not only align horizontally but also has a vertical component. The closer to the magnetic poles, the steeper the dip angle. A dip circle can be used to measure this dip angle. It is basically a compass for the vertical direction.

Compass points horizontally and flat-Earthers wrongly use it as “evidence” of a flat Earth. In reality, a compass is balanced to counter the effect of magnetic dip. We can use a dip circle to measure the actual dip angle of the Earth’s magnetic field.

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Confusing Won’t with Can’t

Flat-Earthers like to confuse won’t with can’t. If they notice an act that would support spherical Earth, but we do not do, they will incorrectly claim, “it must be impossible because Earth is flat.”

There are many things we can do but decide against doing for various reasons. In other words, “we can but won’t.” The fact that we won’t do a thing does not necessarily mean we can’t do it.

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Apollo 8 vs Apollo 11 Earthrise Photos

A hoax in flat-Earth circles claims that Earth in the Earthrise photo taken by Apollo 8 is identical to a similar photo taken by Apollo 11. In reality, they are clearly not identical at all.

It might have been caused by an error by an online source or someone trolling flat-Earthers. However, it demonstrates flat-Earthers’ lack of critical thinking, as it can be easily shown the claim is false by finding the originals from NASA’s image archive.

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Perspective and the Lake Pontchartrain Transmission Line

The Lake Pontchartrain power transmission pylons demonstrate Earth’s curvature. Flat-Earthers invented various excuses to dismiss the observation, including the excuse that it was just a perspective effect.

If it were just a perspective effect, the same parts of the pylons would line up in a straight line, converging into a distant point. In reality, they do not line up in a straight line but are visibly curving downward due to the curvature of the Earth.

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Flat Earthers’ Excuses About the Cavendish Experiment

Flat-Earthers reject gravity. They use various excuses to discredit the Cavendish experiment, an important experiment about gravity.

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Weighing Scale vs Weighing Balance

A weighing scale measures mass by measuring the gravitational force exerted by the object we measure. Because the magnitude of the force depends on the strength of the gravitational acceleration, the result can vary depending on the location. It is the reason the scale needs to be calibrated after it is moved to another location.

On the other hand, a balance measures mass by comparing the object’s mass to a previously known mass. Because both masses are affected by the same gravitational acceleration, a balance is not affected by the change in gravitational acceleration.

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Authagraph Map Projection

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Authagraph is a map projection that attempts to preserve the size and shape of landmasses. It was popularized by the media.

The media dubbed the Authagraph as “the most accurate world map.” Flat-Earthers use it as “evidence” of the failure of science to describe the world. In reality, no world map can avoid all distortion. Authagraph attempts to preserve the accurate size and shape of landmasses at the expense of other properties.

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