Humans Are Social Beings and Science is a Social Process

Humans are social beings. We depend on each other; not everything we need to do can be done by ourselves. We do not produce every food we eat every day, and the same applies to practically every other aspects of our lives.

We often hear flat-Earthers ask if we have researched by ourselves all the things we claim. If we have not researched it by ourselves but only rely on information from third-party, then —according to them— we should not accept the information. It is merely their way to undermine society, and disconnect us from the rest of society.

Continue reading “Humans Are Social Beings and Science is a Social Process”

Eight Inches Per Mile Squared

The “eight inches per mile squared” is a rule of thumb to determine the drop height due to the curvature of the Earth. It does not account for the observer’s height and atmospheric refraction. And therefore, the rule is unsuitable to determine the amount of obstruction of a distant object due to Earth’s curvature.

Many Flat-Earthers often use the “8 inches” rule to reach the conclusion similar to “X is visible, but at the distance of Y miles, X should be Z feet below the horizon, so the Earth is flat.” They are wrong. The “8 inches” rule is the wrong tool for the purpose as it does not account for the height of the observer and atmospheric refraction.

Continue reading “Eight Inches Per Mile Squared”

Balloon Satellites

In the context of spaceflight, a satellite is an object that has been intentionally placed into orbit. A few of these satellites are balloon satellites. They are satellites that are inflated with gas after they have been put into orbit. There are also other human-made objects which are also called satellites, only placed in a much lower altitude, and with a very different operating method. These include the geostationary balloon satellites and atmospheric satellites.

Flat-Earthers deny the existence of satellites, and after they discovered the existence of balloon satellites, they started to use the fact as “proof” that orbiting satellites do not exist. It is the fallacy of hasty generalization. Using the same “logic” they are using, we can use the existence of trucks to “prove” buses don’t exist.

Continue reading “Balloon Satellites”

Shill Gambit

The shill gambit is a fallacy where one party dismisses another party’s arguments by proclaiming them to be on the payroll of some conspiracy, without having any evidence other than the arguments themselves. The shill gambit is a type of ad hominem and poisoning-the-well fallacy. It shifts from addressing the substance of the argument to attacking the person and their credibility instead.

Flat-Earthers would usually commit the shill gambit when they feel cornered. They would accuse anyone outspoken against flat Earth to have been paid by the global conspiracy. We at get these accusations a lot.

Continue reading “Shill Gambit”

The Variation of Earth’s Gravitational Acceleration

The gravity of Earth varies on the different location on Earth. The variation is caused by the difference in latitude, altitude or depth, and local geology & topography. In most cases, the centrifugal acceleration from Earth’s rotation is also already accounted for in the value of Earth’s gravitational acceleration.

Flat-Earthers claim that according to science, the Earth’s gravitational acceleration is always constant at 9.8 m/s² everywhere on Earth. And they are using the claim to prove Earth is not a rotating sphere. In reality, the magnitude of Earth’s gravitational acceleration varies on the different location on Earth.

Continue reading “The Variation of Earth’s Gravitational Acceleration”

Humber Bridge and Earth’s Curvature

The Humber Bridge, near Kingston upon Hull, East Riding of Yorkshire, England, is a 2.22-kilometer (1.38 mi) single-span road suspension bridge, which opened to traffic on 24 June 1981. When it opened, the bridge was the longest of its type in the world.

The towers, although both vertical, are 36 mm (1.4 inches) farther apart at the top than the bottom due to the curvature of the earth.


James Van Allen and the Van Allen Radiation Belts

In 1958, James Van Allen discovered the existence of the Van Allen radiation belts. Conspiracy theorists, including flat-Earthers, use it to “prove” the Apollo Moon landings were faked and never happened. To dispel the hoax, James Van Allen himself wrote letters clarifying the false allegation.

“The recent Fox TV show, which I saw, is an ingenious & entertaining assemblage of nonsense. The claim that radiation exposure during the Apollo missions would have been fatal to the astronauts is only one example of such nonsense.”

Both the discovery of the Van Allen radiation belts and the statement that the radiation belts do not prevent space travel came from James Van Allen. Conspiracy theorists cannot merely quote one when it appears to support their belief and conveniently reject the other if it is against them. Continue reading “James Van Allen and the Van Allen Radiation Belts”

Flat-Earth “Perspective” is not Real-World Perspective

To an observer, the law of perspective will cause objects moving away in a straight line to:

  1. appear to approach the vanishing point but never quite reach it,
  2. never appear to go across the vanishing point,
  3. appear to shrink in size,
  4. never appear to be cut in half unless when it is obstructed by another object.

If the Earth were flat, sunsets, sunrises, and other general phenomena where objects are not visible due to Earth’s curvature should not occur. To “fix the problem,” flat-Earthers invented the explanation that the apparent obstruction of a distant object can occur on a flat Earth due to “perspective.” Their “perspective” is simply a baseless ad-hoc explanation that does not resemble how the real-world perspective works.

Continue reading “Flat-Earth “Perspective” is not Real-World Perspective”

Notable Effort Fallacy

The fallacy of notable effort is committed if one accepts good effort as a valid reason to accept the conclusion, even though the effort is not related to the truth.

Flat-Earthers would often over-emphasize their efforts in proving a flat earth and belittling that from ‘globe-earthers’. Then they take the purported noteworthiness of their efforts to conclude that the Earth is flat. This is the fallacy of notable effort. Putting in more effort does not mean the conclusion is more correct.

Continue reading “Notable Effort Fallacy”

JPEG Compression

JPEG is a method of lossy compression of digital images. When a photograph is saved in the JPEG format, some details imperceptible to our vision are discarded. The JPEG compression reduces the file size at the expense of perfect image reproduction.

Flat-Earthers like to perform “investigations” by adjusting brightness, contrast, levels or curve of an image to find evidence of tampering. If they find irregularities, they will proclaim the picture has been faked. In most cases, these are only JPEG compression artifacts and do not prove anything.

Continue reading “JPEG Compression”

Sun Dog

A sun dog is an atmospheric optical phenomenon that consists of a bright spot separated by 22° from the Sun to one or both sides of the Sun. It is caused by the refraction of sunlight by ice crystals in the atmosphere.

Flat-Earthers claim that a sun dog is caused by the reflection of sunlight by the mythical dome enclosing the flat Earth, that there are multiple suns, or other equally implausible reasons. They are wrong. A sun dog is simply an optical phenomenon that occurs in cold locations where ice crystals can accumulate in the atmosphere.

Continue reading “Sun Dog”

Geocentrism: Incompatible with the Flat Earth Model

Featured Video Play Icon

Geocentrism is a superseded description of the universe with Earth at the center. Under geocentrism, celestial bodies all orbited Earth. Geocentrism was the accepted model of the Universe for approximately 18 centuries; before we knew that Earth orbits the Sun —or what we call as heliocentrism.

We often observe flat-Earthers using the arguments for geocentrism as if it supports the flat Earth model. They are wrong. Under geocentrism, the Earth is a sphere, located at the center of the universe. It is not remotely compatible with the flat Earth model, which is an even more archaic understanding of the Universe.

Continue reading “Geocentrism: Incompatible with the Flat Earth Model”

Airplane and Earth’s Rotation

An airplane exists on Earth. It has the same motion as the surface of the Earth, including the Earth’s rotating motion. The motion of the airplane itself is measured relative to the surface of the Earth.

Flat-Earthers think that due to Earth’s rotation, an airplane should not be able to fly east or land. They are wrong. The speed of an airplane is relative to the surface. It retains the motion of the Earth and does not need to chase Earth’s rotation.

Continue reading “Airplane and Earth’s Rotation”

Special Pleading

Special pleading is applying standards, principles, or rules to other people or circumstances, while making themselves or certain circumstances exempt from the same critical criteria, without providing adequate justification.

Flat-Earthers like to impose various unwarranted rules and conditions —that were invented spontaneously— to rule out evidence against flat Earth. However, when it comes to the things they regard as ‘evidence’ in favor or a flat Earth, they are more than happy to ignore the rules and conditions that they previously invented.

Continue reading “Special Pleading”

False Analogy

A false analogy is a fallacy in which similarity in one respect of two concepts, objects, or events is taken as sufficient to establish that they are similar in another respect in which they are actually are not similar.

Almost all of what flat-Earthers happily claim as “experiments” are actually false analogies. They would take everyday objects and use them as analogies for actual objects. In reality, a shared similarity in both the analogy and the real thing is not sufficient to ‘prove’ both are similar in some other respect.

Continue reading “False Analogy”


An analemma is a photograph or diagram showing the position of the Sun in the sky, as seen from a fixed location on Earth at the same mean solar time, as that position varies over the course of a year. The diagram will resemble the figure 8.

The north-south component of the analemma results from the change in the Sun’s declination due to the tilt of Earth’s axis of rotation. The east-west component results from the non-uniform rate of change of the Sun’s right ascension, governed by the combined effects of Earth’s axial tilt and orbital eccentricity.

Continue reading “Analemma”

Air Distance vs Surface Distance

The cruising altitude of a jet airliner is about 33000-42000 ft or 10000-12800 m. It is very tiny compared to the radius of the Earth of 6378 km. Therefore, the distance measured at the cruising altitude does not differ much compared to the surface distance.

Some flat-Earthers claim that if Earth is a sphere, the distance traveled by a jet airliner would have been multiple times the surface distance. They are wrong. The air distance at 33000 ft is only 0.16% farther compared to the surface distance.

False Dichotomy

A false dichotomy or false dilemma is a logical fallacy which involves presenting two opposing views, options, or outcomes in such a way they seem to be the only possibilities: if one is true, then the other must be false. In reality, there can be many in-between or other alternative options, not just two mutually exclusive ones.

Flat-Earthers like to ‘disprove’ spherical Earth using their own ignorance about various issues. Then they would regard their erroneous belief that spherical Earth has been disproven as “proof” that the Earth is flat. This is fallacious reasoning because the Earth can be in another shape instead.

Continue reading “False Dichotomy”

Excessively Defishing Fisheye Images to Flatten the Curved Horizon

Defishing is a process for removing barrel distortions in fisheye images. It takes fisheye images, and convert them to normal, rectilinear images that preserve straight lines. Different fisheye lenses can have a different amount of distortions, and thus, require a different defishing strength.

Some flat-Earthers would deliberately use stronger defishing parameters than necessary for the lens being used. Their intention is not to remove the barrel distortion in the resulting images, but also to introduce pincushion distortions to the images. Pincushion distortion is the reverse of barrel distortion. It would curve a straight line to the other direction from what would be produced by the barrel distortion in fisheye lenses. At a specific position in the scene, it would make the curved horizon to appear flat.

Continue reading “Excessively Defishing Fisheye Images to Flatten the Curved Horizon”

Sunset on Mountains

Featured Video Play Icon

During a sunset, mountain peaks lose sunlight later than areas around them. From a viewer observing a mountain, a shadow can appear ascending from the base to the peak. And conversely, during a sunrise, mountain peaks get sunlight before the areas around them and a shadow can appear descending from the peak to the base.

This phenomenon occurs because the Earth is a sphere. As the altitude increases, the hours of daylight become longer. It makes the sun rise earlier and set later.

Continue reading “Sunset on Mountains”