Dark Part of the Moon & Its Visibility During the Day

Black is a color that results from the absence of light. A dark or black object emits practically no light. It does not emit “black light.”

Flat-Earthers claim the dark part of the moon should appear black during the day. In reality, they fail to understand that black is caused by the lack of light, not by the emission of “black light.”

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Horizontal Motion of Smoke

The horizontal motion of a rising smoke occurs due to the horizontal motion of air relative to the object releasing the object. If the air is stationary relative to the object releasing the smoke, then the smoke will rise straight upward.

Flat-Earthers claim the motion of smoke rising straight up “proves” Earth is stationary. In reality, the horizontal motion of smoke is caused by the motion of surrounding air, relative to the object releasing the smoke, not the motion of the object itself.

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Blood Moon: Why The Moon Turns Red During a Total Lunar Eclipse

The Moon becomes red during a total lunar eclipse because Earth’s atmosphere acts like a lens and refracts sunlight toward the Moon. It also scatters bluish components of sunlight more strongly and lets more reddish components reach the Moon.

The Moon does not become totally dark during a total lunar eclipse, and flat-Earthers use it as “evidence” the Moon is not in Earth’s shadow during a lunar eclipse. In reality, it occurs due to optical phenomena involving Earth’s atmosphere.

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Pressure Difference Without a Barrier

Atmospheric pressure decreases as altitude increases. A pressure difference can occur without a barrier. Other factors, like gravity, can cause a pressure difference.

Flat-Earthers claim a pressure difference cannot possibly occur without a barrier, like Earth’s atmosphere next to the vacuum of space. In reality, it is not difficult to demonstrate that a pressure difference can exist without a barrier.

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Geocorona

In 2019, scientists discovered that Earth’s atmosphere consists of a hydrogen cloud called the geocorona that extends to the Moon and beyond. Its density is minuscule, practically vacuum, and does not affect space travel.

Flat-Earthers claim this is an “admission” as the Moon has always been “inside the dome” in their flat Earth model. In reality, the discovery does not change much about what we already know.

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Atmospheric Pressure and the Vacuum in Space

Atmospheric pressure decreases as altitude increases. There is no visible boundary between Earth’s atmosphere and space in terms of pressure. There is no abrupt drop in pressure where space begins.

Flat-Earthers assert that it is impossible for the pressurized atmosphere to meet the vacuum of space without any barrier. In reality, the pressure changes gradually. There is no sudden pressure drop between the atmosphere and space.

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Vacuum Implosion

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A vacuum implosion can occur if a sealed enclosure has less pressure inside it than outside it, and the structure is not designed to withstand the pressure difference.

Flat-Earthers use vacuum implosions to ‘disprove’ space travel in the vacuum of space. In reality, 1. it is possible to engineer structures that can withstand such a pressure difference; and 2. in space, the inside is pressurized while the outside is a vacuum, which simplifies the engineering considerably.

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The Appearance of Sunset and Atmospheric Refraction

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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.

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Vacuum in Space and Earth’s Atmospheric Retention

The Earth retains an atmosphere because gravity pulls air particles toward the center of the Earth. Without something affecting the air —like gravity— air particles would move toward lower pressure, and Earth would lose its atmosphere.

Flat-Earthers claim that Earth should not be able to have an atmosphere because without any barrier separating Earth’s atmosphere and space, it would have been sucked by the vacuum in space. They are wrong. Gravity pulls air and allows Earth to retain an atmosphere.

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Rayleigh Scattering

Earth’s atmosphere glows in blue because of Rayleigh scattering. It scatters sunlight to every direction. Bluish colors are scattered more than reddish colors. This results in the bright blue color of the sky in the daytime.

There are many misconceptions in the flat Earth community that arise from the lack of understanding of Rayleigh scattering.

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White Alice and the Troposcatter Propagation

Troposcatter is a signal propagation method using the scattering phenomenon in the upper troposphere. As the signal pass through the upper troposphere, some of the energy is scattered back toward Earth, allowing the receiver station at the correct location to pick up the signal.

White Alice is a decommissioned troposcatter network in North America. Some flat-Earthers invented the “explanation” that the various satellite-based services we enjoy today are using White Alice. They are wrong. White Alice and other troposcatter networks cannot possibly replace all the services provided by satellites.

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The Dark Sky on the Lunar Daytime

On Earth, daylight sky is glowing in bright blue due to Rayleigh scattering. Sunlight is scattered in every direction by the oxygen and nitrogen molecules in Earth’s atmosphere.

Such the phenomenon does not happen on the Moon, causing the dark sky of the Moon. Flat-Earthers claim that the dark sky of the Moon captured by photos and videos taken from the Moon are “proof” there is misconduct. They are wrong. Just because Earth’s sky is bright blue, it does not mean it will be like that on the Moon and other planets.

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Earth’s Atmosphere Rotation

Earth’s atmosphere is part of the Earth. It practically follows Earth’s rotating motion like the rest of the Earth. Due to various factors, Earth’s atmosphere has relatively small and uneven movement relative to the surface. We call it ‘wind.’ The fastest wind ever recorded is about 408 km/h, relative to Earth’s surface.

Many misconceptions about Earth arise from the wrong idea that only Earth’s solid body is rotating, but the atmosphere is not. If it is true, then we should always feel the wind with the speed of 1674 km/h near the equator, or more than 4× the fastest wind ever recorded. We don’t feel such a wind, and thus we know our atmosphere is moving at practically at the same speed as Earth’s surface.

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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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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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Atmospheric Refraction and the Position of the Sun in the Flat-Earth Model

If the Earth is flat, then the Sun would have been visible from the entire Earth, but that’s not the reality. So, to rescue the concept of the flat-Earth from being falsified, they invented an ad-hoc hypothesis that the Sun appears to set because of perspective and refraction.

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Atmospheric Refraction

Light waves are not always moving in a straight line. When it passes through a medium of a different refractive index, the waves will deviate. The phenomenon is called refraction and described according to Snell’s Law.

Earth’s atmosphere has variation in air density that depends on the altitude. As the refractive index changes with the density of the medium, light waves passing through Earth’s atmosphere also experience refraction.

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The Apollo Missions and Van Allen Radiation Belts

Van Allen Radiation Belt is a zone of radiation encircling the Earth. To flat-Earthers, Van Allen Radiation Belt is ‘evidence’ of the impossibility of space travel. To the rest of us, the Van Allen Radiation Belt is one of the challenges which is not impossible to overcome.

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Space Flight and the Temperature in the Thermosphere

The thermosphere is a layer of the Earth’s atmosphere from about 95 km­ to 600 km. It is named ‘thermosphere’ because its temperature increases with altitude. The temperature in the thermosphere can reach 2500°C. However, air density in the thermosphere is very low to the point that heat conduction practically does not occur. Objects in the thermosphere will feel cold.

Flat-Earthers discovered that the temperature in the thermosphere could reach 2500°C. They are happy to ignore the other information which usually accompanies it: the air density up there is also far lower.

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