The Sun is 1,391,016 km (864337 mi) in diameter and 146,600,000 km (93,000,000 mi) from us. These facts are consistent with everyday observations.
Flat-Earthers have a different idea about the distance and the size of the Sun. However, on careful examinations, the numbers are inconsistent with everyday observations.
Continue reading “Proportions”
There are several time-lapse videos taken on board of a New York – Moscow flight, looking northward through a window on the left side. In the videos, the sky never looked fully dark, and the sun was visible most of the time on the flight.
Flat-Earthers erroneously assumed that the phenomenon is not possible if Earth is a sphere and that it is “evidence” the Earth is flat. In reality, everything in the videos can be easily explained and is fully consistent with the spherical Earth model.
Continue reading “New York JFK – Moscow SVO Flight Time-Lapse Videos”
The appearance of sunset depends on atmospheric conditions. Thermal inversion can irregularly refract light coming from the sun and distort the image of the Sun seen from an observer.
Some flat-Earthers observed a specific appearance of sunset and presented the fact as if it “proves” a receding sun in the flat-Earth model. They are wrong. The appearances of the sunsets are the results of atmospheric refraction.
Continue reading “The Appearance of Sunset and Atmospheric Refraction”
Light travels in a practically straight line over a short distance. We often use this property of light to determine if an object is flat or straight from visual observation.
Some flat-Earthers start with the wrong assumption that a specific object is flat, then attempt to redefine how our vision works from that. They are wrong. From visual observation, we can determine if an object is flat, not the other way around.
Continue reading “Line of Sight: Determining if an Object is Straight or Flat”
The canceling hypotheses fallacy occurs when someone defends their hypothesis by proposing a second hypothesis to explain the lack of evidence in support of the first hypothesis. In effect, the second hypothesis cancels or undermines the prediction made by the first hypothesis.
Flat-Earthers like to demonstrate what they regard as ‘evidence’ of a flat Earth. However, when it is demonstrated that the evidence is wrong, they would invent a second hypothesis to defend the original hypothesis against the evidence of the contrary. They do it without attempting to bring sufficient proof of the second hypothesis.
Continue reading “Canceling Hypotheses Fallacy”
Lighthouses are equipped with powerful lights. In a dark night, even if Earth’s curvature obscures the entire structure of the lighthouse, the phenomenon of the loom of the light allows their lights to be visible beyond the horizon; not unlike how the beam of a green laser is visible to our eyes.
Flat-Earthers like to point out the cases where the light from a lighthouse is visible even if the lighthouse should be completely obscured by Earth’s curvature. They would claim it as “proof” that the Earth is flat. They are wrong. The loom of the light lets us see the light even when the lighthouse itself is below the horizon.
Continue reading “Lighthouses and the Loom of the Light”
If a distant boat is not visible, then it is because of at least one of these reasons:
- Our eyes have limited angular resolution and are unable to resolve the ship at that distance.
- The atmospheric condition is limiting our visibility.
- The curvature of the Earth obscures the ship.
Flat-Earthers like to demonstrate that a previously invisible ship at a distance can be made visible by zooming in. They would use it to disprove Earth’s curvature. They are wrong. There are reasons other than Earth’s curvature that can obscure a distant boat.
Continue reading “Zooming In On Distant Boats Does Not Disprove Earth’s Curvature”
The Nikon P900 and Nikon P1000 are cameras with a very high zoom factor. However, like most other cameras, they have difficulties focusing and exposing bright & small objects against dark backgrounds. They will require special tricks to get proper images of stars and planets.
Some flat-Earthers pointed their Nikon P900 or P1000 to stars and planets, took out of focus images of them and believed the photos are the “real images of stars and planets.” In reality, the photos are simply the results of their failures to operate their cameras.
Continue reading “Nikon P900 & P1000: Correctly Focus & Expose Stars & Planets”
The angle (or altitude) to Polaris approximately corresponds to the latitude of the observer. This fact is observed on every location on Earth where Polaris is visible.
By tracing the path to Polaris from multiple locations on the flat Earth model, the lines will not point to a consistent position of Polaris. The reason is that the Earth is a sphere and the flat Earth model does not represent reality.
Continue reading “Polaris Altitude from Multiple Locations on Earth”
‘Flat’ and ‘Level can mean approximately the same thing in everyday conversation. But in the context of science and engineering, they have different meanings. ‘Flat’ describes a planar surface. ‘Level’ means at the same height or perpendicular to the direction of Earth’s gravity.
Flat-Earthers interpret the word ‘level’ as if it always has the same meaning as ‘flat.’ However, in the scientific context, the two words have different meanings. Insisting that both words to have the same meaning is the fallacy of appeal to definition.
Continue reading “‘Flat’ vs ‘Level’”
The apparent size of the Sun is constant throughout the day, from sunrise to sunset, seen from anywhere on Earth. This fact disproves the flat Earth model and is only consistent with the spherical Earth model.
Flat-Earthers like to show us videos of the Sun that appears shrinking during a sunset. They merely failed to control the exposure. Using a solar filter or the in-camera exposure settings, the size of the Sun will appear constant during a sunset.
The apparent size of the Sun is constant throughout the day, seen from anywhere on Earth, from sunrise to sunset. This fact is only possible if the Sun is very far compared to the distance between any two observers on Earth.
Some flat-Earthers are confused that two observers on the opposing locations on Earth can observe the Moon at the same time, and they would use it as ‘proof’ that the Earth is not a sphere. It is merely a spatial cognition problem by the flat-Earthers.
Any observer on Earth’s surface has 180° vertical field of view over the entire sky. They can observe objects low on the horizon, not just objects above them. Observers on the opposing sides of the Earth would have no problem seeing the Moon at the same time.
Continue reading “Visibility of the Moon from Two Opposing Locations on Earth”
Railways are built to follow Earth’s terrain, minimizing the grade/slope as much as possible. Consequently, they all follow Earth’s curvature. And many of them were built by explicitly accounting for the curve of the Earth.
Flat-Earthers claim that railroads are straight, and never built by accounting for Earth’s curvature. They are wrong. The leveling works were done in such a way to minimize the effect of Earth’s curvature. There are also multiple books describing railroad constructions where the curvature of the Earth is specifically accounted for.
Continue reading “Railroads and Earth’s Curvature”
An online digital photo forensics tool like FotoForensics.com uses Error Level Analysis (ELA) to discover the error level differences on a photograph that was saved using a lossy compression algorithm, like JPEG. ELA algorithm enables us to determine if a photo was digitally modified. Similar surfaces and similar edges should appear similar under ELA. If not, it might indicate a digital manipulation.
Flat-Earthers like to use ELA to ‘prove’ a photo has been tampered with. It occurs because they do not understand how ELA works. Most of them appear to assume if the picture is an original, it would show a uniform ELA. Using such a digital forensic ‘skill’, we can actually ‘prove’ all digital photos as fake.
Continue reading “FotoForensics & Error Level Analysis (ELA)”
Observing Earth’s curvature is more difficult when we are too close to Earth’s surface. The highest place within reach of the general public is a commercial passenger flight. Even then, it is still difficult to casually discern the curvature of the Earth from an airplane. With some effort, it is possible to observe the curve of the Earth from a location closer to the surface, as long as we are willing to do some planning and careful observation.
Continue reading “Observation of Earth’s Curvature from Near the Surface”
Occasionally, some flat-earthers would ask nicely and demand that the scientific and professional community treat them with respect and take them seriously. They ask everyone to respect them because only with mutual respect, then it would enable everyone to understand and determine the actual shape of the Earth.
Such an attitude is what is expected by the general public. However, respect works both ways. If a flat-Earther starts respecting scientists, professionals & the general public, it would be no longer possible for them to retain their belief in a flat Earth. Unfounded slander to a lot of people comes in a package in the belief of a flat Earth, and can never be separated.
Continue reading “Mutual Respect”
The geoid is the shape that the ocean would take under the influence of the gravity and rotation of Earth alone. The geoid is smooth but irregular because Earth’s density and surface are uneven. ‘Height above sea level’ is measured relative to the geoid.
Some flat-Earthers claim that measuring height above sea level is not possible if the Earth is spherical. They are wrong. Height/altitude/elevation is usually measured relative to the geoid, which is approximately a sphere. The geoid is a more accurate model depicting the shape of the Earth, compared to the spherical & ellipsoid model.
Continue reading “Geoid and Altitude Above Sea Level”
In 1881, Albert A. Michelson performed an experiment in an attempt to prove the existence of aether. Aether was a hypothesized material that fills the region of the universe. Scientists knew light is a form of wave, and because all other waves require a medium to propagate, they formulated the aether hypothesis, in which light can propagate. However, Michelson’s experiment produced a zero effect.
In 1960, Bernard Jaffe wrote Michelson’s biography in the book “Michelson & the Speed of Light.” Unscrupulous flat-Earthers quoted a lone paragraph from the book out of the intended context, and present it as if Michelson proved the Earth is stationary.
Continue reading “Albert Michelson in “Michelson and the Speed of Light””
Flat-Earthers like to perform the experiment involving lasers to ‘disprove’ Earth’s curvature. If they observe a laser beam from the other side of a lake or an ocean, they would wrongly conclude Earth’s curve does not exist. It was merely a misunderstanding of how lasers work.
Continue reading “Flat-Earthers’ Laser Tests are Misleading”
The argument from persecution is a fallacy that asserts that if your ideas provoke others to vilify or suppress you, then you must be right. Note: this fallacy is better known as the Galileo gambit. However, in this case, flat-Earthers themselves are the ones defaming Galileo and his ideas.
Flat-Earthers commit the fallacy when they show off that their ideas are being mocked, censored, or deleted. They get such the treatment not because they are right. But because by believing in a flat Earth, they have to accuse a lot of people of being dishonest and part of a global conspiracy.
Continue reading “Argument from Persecution”