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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A camera in automatic mode will evaluate the entire scene and choose the exposure automatically. If the entire scene appears too dark, the camera will increase the exposure. If the entire scene is too bright, it will decrease the exposure.
If the intended object is small, bright, and on a dark background like a sunset, changing zoom will affect the overall brightness of the entire scene. The automatic mode might choose an incorrect exposure. It is the source of much flat-Earth misinformation & can be corrected using manual exposure.
Continue reading “Changing Camera Zoom Changes the Exposure in Automatic Mode”
Using a drone, we can observe a sunset, then climb up and watch the same sunset again for the second time. The observation is only possible because Earth is a sphere.
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Camera zoom works by enlarging the center portion of the image, or in other words, by making its field-of-view narrower. Zooming in on the setting sun will not reveal more of the sun and will only enlarge the size of the sun in the resulting image.
Flat-Earthers claim that zooming in on a setting sun will reveal the full sun and somehow lift it out of the water. In reality, they used incorrect exposure settings, making the sun still above the horizon appear already half-obscured by Earth’s curvature.
Zooming on the setting sun will never reveal the sun already obstructed by Earth’s curvature.
Continue reading “Zooming-In on the Setting Sun”
The Big Diomede and Little Diomede are islands in the middle of the Bering Strait. Although only 4 km apart, they belong to different countries and have a 21-hours time zone difference.
Flat-Earthers noticed the number of polar days is different on both islands during the summer solstice & they used it to discredit science. In reality, the islands are very close to the Arctic circle, & during the June solstice, the sun’s path is almost parallel to the horizon. A tiny change in latitude or height can result in a large change in sunrise & sunset times.
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The “Flat Earth Dome Model” (walter.bislins.ch/FED) is an app created by a fellow flat Earth debunker, Walter Bislin. The app attempts to map observed reality to the flat Earth model. Lines in the app portray how light rays must have traveled if Earth were flat. They demonstrate that light must bend in a physically impossible way if Earth were flat, disproving a flat Earth.
Videos of the app are circulating in flat-Earth communities, and flat-Earthers fail to understand what the app is showing. They incorrectly assume the app “proves” a flat Earth when in reality, it thoroughly disproves the flat Earth model.
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Mercury and Venus are inferior planets. Their orbits are closer to the Sun than Earth. We can see these planets if they are above the horizon, and it will be easier if the Sun is below the horizon. Generally, both planets can be seen early or late in the night.
Flat-Earthers claim we should not be able to see Mercury and Venus as they are closer to the sun, and at night we are facing away from the sun. In reality, early and late in the night, we can look toward the general direction of the Sun & observe both planets.
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Sun glitter is a bright, sparkling light formed when sunlight reflects from water waves. A rippled by a locally smooth surface such as water with waves will reflect the sun at different angles at each point on the surface of the waves. As a result, a viewer in the right position will see many small images of the sun, formed by portions of waves oriented correctly to reflect the sun’s light to the viewer.
Flat-Earthers use the long shape of the sun’s reflection on a water surface to “prove” Earth is flat. In reality, the shape of the reflection is the result of the rippling water surface. It can easily occur on a curved surface and does not prove a specific shape of Earth.
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Glare can appear around light sources, causing them to appear larger in a photo. The higher the exposure value of the camera, the larger the glare will appear on the resulting photo.
Much flat-Earth misinformation arises from misunderstandings about photography, such as about glare and how to eliminate glare by changing the exposure or by using a solar filter. Using the exposure setting for everyday scenes to capture a photograph of the sun will give us a glare around the Sun. To take a photo of the actual size of the Sun, we need to reduce the exposure, either by changing the in-camera exposure settings or by using a solar filter.
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A full moon can only occur if the Sun is directly opposite the Moon in the sky, and it will never appear near the Sun. There are photos on the Internet showing a full moon next to the Sun. These photos are fakes, and the phenomenon cannot possibly occur in the real world.
Flat-Earthers discovered images on the Internet showing a full moon next to the Sun, and they use it as “evidence” that moonlight is not reflected sunlight. In reality, these people are not aware that these photos are obvious fakes.
Continue reading “Images of Full Moon During Sunset”
Flat-Earthers often show us images of a lamp illuminating a dark wall to demonstrate —incorrectly— how night can happen on a flat Earth.
In the images, the areas farther from the lamp appear dark. Due to the inverse-square law, areas farther than the source of light receive less light. However, these areas still receive light nonetheless. From these dark areas, the lamp is still visible. This contrasts with what happens at night, that sunlight is nonexistent and the sun is not visible.
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Flat-Earthers like to mention an astronomical event or a specific celestial geometry and insist it cannot possibly occur if Earth is a rotating sphere orbiting the sun. They would incorrectly proclaim it as “evidence” of a flat, stationary Earth.
We can ask them the time of the event and the observer’s location, then use Stellarium or a similar app to simulate the event. If it produces the same result as the actual observation, then they have nothing to complain about. And the problem was just caused by their failure to understand and to create the correct model.
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Sunlight is very intense. It can cause glare to appear around the sun, and as a result, the sun can appear larger than its actual size. To observe the sun’s actual size, we need to eliminate the glare by reducing the camera’s exposure or using a solar filter.
During sunset, sunlight gradually becomes less intense, and sun glare gradually becomes smaller. If the glare is not eliminated, the sun can appear as if it is shrinking, and flat-Earthers incorrectly use it as “evidence” that the sun is moving away from us.
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Flat-Earthers performed the coin on a table “experiment” to “explain” how a sunset can occur on a flat Earth. Instead, it tells us more about their confirmation bias.
This is probably one of the most ridiculous flat-Earth arguments. It is so obviously wrong that many of us are having trouble explaining it and cannot accept that a member of the human race can fall for it.
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A selenelion is a rare lunar eclipse where the Sun and the Moon are both visible at the same time. An even rarer form of selenelion occurs if it is a partial lunar eclipse, and the upper part of the Moon is eclipsed. Some call this an “impossible eclipse.”
Flat-Earthers claim that such an eclipse should not be possible to occur because the Earth’s shadow is in the wrong position. In reality, it is possible to happen because the observer is looking slightly downward due to the dip of the horizon and atmospheric refraction.
Continue reading “The Impossible Eclipse”
A selenelion occurs during a lunar eclipse when the sun and moon are observed above the horizon. Atmospheric refraction bends light rays and lifts the image of the sun, and the moon typically up to 0.6°, so both can appear above the horizon.
Flat-Earthers assert that a selenelion should not be possible if Earth is a sphere due to the fact during a lunar eclipse, the sun and moon are 180° apart. In reality, a selenelion is possible because Earth’s atmosphere refracts light.
Continue reading “Selenelion: The Phenomenon Where Both the Sun and Moon Are Visible During a Total Lunar Eclipse”
An inferior mirage is a phenomenon in which atmospheric refraction bends light rays to produce a mirrored image below a real object. It occurs when a hot surface heats the layer of air above it, placing it below a colder & denser layer of air.
Flat-Earthers like to use inferior mirages to “explain” how a distant object can appear partly obstructed if the Earth is flat. In reality, an inferior mirage cannot produce an appearance similar to an object partially obscured by Earth’s curvature.
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Earth’s shadow is the shadow that Earth casts into its atmosphere, toward the opposite point from the sun. Above Earth’s shadow is the Belt of Venus, a pink band from the scattering of sunlight through the atmosphere.
Earth’s shadow lies at the antisolar point —the point opposite the sun. It rises when the sun sets and sets when the sun rises. The phenomenon shows us that the sun really goes below the horizon and disproves the flat Earth model.
Continue reading “Earth’s Shadow and the Belt of Venus”
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”