Observing the ISS from ISS Transits

Flat-Earthers reject the existence of satellites. They are wrong. To prove the existence satellites, we can attempt to take pictures of the ISS when an ISS transit happens, or the ISS passes in front of the Sun or the Moon.

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Observations of Sunspots From Multiple Locations on Earth

Sunspots are darker spots on the surface of the Sun. The location where sunspots appear is unpredictable, but the appearance of sunspots is always the same when observed from anywhere on Earth; only the orientation is different on different observer location. Observers on the opposite position on the Earth will see the sunspots reversed. The reason is that the Earth is a sphere. Any two observers on Earth’s surface are not standing on the same plane.

Some flat-Earthers have spatial awareness difficulties and present the difference of the appearance of sunspots as ‘evidence’ the Earth is not spherical. They are wrong. If the Sun were close as in the flat Earth model, we would see the different appearance of sunspots on the different observer location. In reality, everyone on Earth observes the same appearance of sunspots, only with the different orientation that corresponds to the position of the observer.

Sunset, Camera Zooming, and Autoexposure

There are videos showing the sun to appear to set, but after the camera is zoomed in, the sun is still above the horizon. The reason is that the camera’s autoexposure system is constantly adjusting the exposure, and in such scenes, there’s a difference in overall brightness before and after zooming in.

Flat-Earthers are taking such videos as ‘evidence’ of a receding sun. They are wrong. This is merely a matter of photography. In reality, the sun is not receding, and it has the same angular size throughout the day.

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The Angle of a Shadow During Equinox

During an equinox (March 20 and September 22-23), the Sun is directly above the equator. If we are on the equator, an upright stick will not have a shadow in the middle of the day.

On any other location, the angle between the stick and the direction of sunlight will be the same as the observer’s latitude.

This fact can only occur if the Earth is a sphere, and only if the Sun is very far relative to the size of the Earth.

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The Change of Constellations

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We can’t observe stars moving relative to each other, and the shape of constellations looks the same every night. The reason is not that stars are stationary, but their motions are very slow and cannot be observed over the timescale of human life.

Flat Earthers claim that the fact constellations don’t appear to change as proof the Earth is stationary. They are wrong. Stars have proper motion, but they can only be observed using precise instruments over a long time. Constellations do change, but the change is slow and cannot be perceived over the timescale of human life.

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The Curvature Fitting Game

The amount of curvature that appears in a photograph of a sphere depends on 1. The radius of the sphere, 2. Camera distance from the sphere, 3. Field of view of the camera, and 4. The distortion characteristic of the camera being used.

The ‘curvature fitting game’ has been flat-Earthers’ favorite pastime. They would try to fit a photograph of Earth’s curvature with another. If they find the result is not proportionally correct, they will make fun of it. They are wrong. Two different photos of a sphere can be taken differently and would show a different curve, even if the object being photographed is the same object.

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The False Dilemma of the Figure of the Earth

There are several models explaining the figure of the Earth. These models vary in the way they are used, in their complexity and in the accuracy with which they represent the size and shape of the Earth. These models are sphere, ellipsoid, and geoid.

Flat-Earthers often take the existence of these multiple models as evidence of disagreement among scientists, and that the shape of the Earth is still in contention. They are wrong. All these models are valid models, only with different complexity and accuracy.

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Rockets and the Lack of Oxygen in Space

Most combustion engines work with oxygen from Earth’s atmosphere as its oxidizing agent in the combustion process. But in the case of rockets, there’s no oxygen in space. It would have to bring the oxidizer in addition to its fuel or use monopropellant which doesn’t require an oxidizer.

Flat-Earthers claim rockets should not be able to work in space because there’s no oxygen in space. They are wrong. The lack of oxygen in space is merely an engineering problem which is not impossible to solve. Rockets are engineered to carry its oxidizer or utilize monopropellant which does not require an oxidizer.

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Style over Substance Fallacy

The fallacy of style over substance occurs when one argue the way in which the argument is presented while marginalizing or ignoring the argument itself.

Flat-Earthers are often seen dismissing an argument only because of the way it is presented, and thus, committing the style over substance fallacy.

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The Orientation of the Moon

The Moon looks practically identical from everywhere on Earth because the Moon is very far relative to the distance between observers on Earth. However, its orientation is different when observed from the various locations across the globe. The reason is that the Earth is a sphere: the different observers are not on the same plane and have the different orientations themselves.

Some Flat-Earthers have spatial awareness difficulties and present the difference of the orientation of the moon as ‘evidence’ of a flat Earth. They are wrong. If in their model the Moon is close, we should be able to see the different face of the moon on the different location on Earth. But we clearly don’t.

Schiehallion Experiment

The Schiehallion experiment was an experiment to determine the mean density of the Earth. It involved measuring the tiny deflection of a pendulum due to gravitational attraction from the mountain of Schiehallion, Scotland. The measured deflection was 11.6″ or 0.003°.

Flat-Earthers claim that it is impossible to demonstrate gravity and that it is evidence gravity does not exist. They are wrong. The Schiehallion experiment was one of the first practical experiments of gravity done on Earth.

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The so-called “Experiment” Done by Flat-Earthers

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We often see flat-Earthers create a ‘miniaturized physical model’ of a real object and present them as ‘proof’ in support of flat-Earth and against spherical Earth. Their M.O. is to observe if the model remotely resembles the actual object in a particular way. If it does, then it is enough for them to conclude the model describe how the real object works.

Conversely, if a real object cannot be miniaturized and still have the same behavior as the original object, they would conclude that the behavior of the original object doesn’t exist.

They would wrongly call creating such models “doing an experiment”.

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The Failure of Flat-Earth Model to Explain Emergency Landings That Occur More to the South

The perpetrators of flat-Earth often take emergency landings as ‘proof’ of a flat Earth. They would point out that the diversion airports used for such emergency landings are somehow consistent with the flat-Earth map.

It is not a coincidence that all the cases of emergency landing they pointed out occurred far in the north. At the locations closer to the north pole, the distortion of the azimuthal-equidistant map (claimed by flat-Earthers as the ‘flat-Earth map’) diminishes. It would seemingly appear as if the ‘flat-Earth map’ can explain the choice of the diversion airports. In many other locations, though, the flat-Earth map would fail to explain it.

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Airborne Early Warning & Control (AEW&C): Mitigating Limited Radar Range Due to Earth’s Curvature

An AEW&C (airborne early warning and control) system is a radar system attached to an aircraft. It can detect objects at a very long range compared to any surface mounted radar system.

The reason is that Earth’s curvature limits the range of a surface-based radar. An airborne radar system mitigates this problem.

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Al-Biruni’s Method to Determine the Radius of the Earth

In the 11th century, Al-Biruni successfully determined the radius of the Earth. He accomplished that by measuring the dip of the horizon from the top of a hill. From the measurements, he was able to calculate the radius of the Earth.

In the 21st century, we can easily repeat the same experiment with practically no effort. We just need a smartphone and an opportunity to observe the horizon from a high altitude, like during a flight.

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The Direction to the Sun vs the Position of the Sun

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If we were to observe the direction to the Sun over the entire course of the day, on multiple locations on Earth’s surface, and then plot the results on the so-called flat-Earth map; then they would not consistently point to the position of the Sun that is calculated from its location on such map.

This fact happens because the flat-Earth map is not the correct description of the real Earth.

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Temperature Variations at the Different Times During the Day

The variation of the temperature at the different times during the day is the result of two primary causes: the difference of the thickness of the atmosphere the sunlight must traverse to reach the surface; and the change of the concentration of sunlight over the same surface area of the Earth.

Flat-Earthers claim that the change in Sun’s distance caused such a difference in temperature and that it can only be explained in a flat Earth. They are wrong.

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Polaris is not Stationary in the Sky

Polaris is a bright star that is close to the north celestial pole. Currently, Polaris is only 0.74° apart from the north celestial pole and the only star visible to the naked eye that is close to the celestial pole. This is why Polaris is popular as a navigational aid in the northern hemisphere.

Some flat-Earthers think that Polaris is stationary and that it is a ‘special star’ because other stars are in motion around it. They would take that as ‘evidence’ that the Earth is motionless. They are wrong. Polaris is merely a regular star, just like the others.

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The Earth is Really Spherical, Not Because “NASA Told Us So”

The fact that the Earth is spherical was known since at least 3rd century BC, or about 24 centuries ago, far before we can send anything to space. We knew the fact from countless observations, and not merely from photos and videos taken from space, or that “NASA told us so.”

On the other hand, flat-Earthers often mention NASA or other space agencies because they don’t have a choice. If they insist on the wrong notion that the Earth is flat, then they would need to invent various excuses why there are photos and videos taken from space.

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Sunglint

Sunglint is a phenomenon that occurs when sunlight reflects off the surface of a water body —like the ocean— at the same angle as an observer is viewing the surface. In the affected area, relatively smooth ocean water becomes a silvery mirror.

In the flat-Earth model, the Sun is assumed to be a ‘local light source.’ They like to use a spotlight or a flashlight as an analogy. They present the sunglint phenomenon as ‘evidence’ of the fact that sunlight is local. They are wrong.

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