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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Total Lunar Eclipse, Drawn to Scale

Any diagram showing two or more celestial bodies is almost never drawn in the correct scale. The reason is that in most cases, any two celestial bodies are spaced too far away relative to their sizes. It is just not possible to draw them in the correct scale and still effectively describes what we want to explain. We don’t have much choice other than drawing them not to scale.

The perpetrators of flat-Earth disseminate the allegations that the diagrams were drawn not to scale because of evil intentions, and not because of legitimate technical reasons. Some people don’t understand this and fell victim to flat-Earth indoctrination.

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The Saros Cycle and Prediction of Eclipses

A long time ago, Babylonians carefully maintained records of the occurrence of eclipses and used these records to predict future eclipses. To honor that, in 1691, Edmund Halley named the interval in a cycle of eclipse using a Babylonian unit of time: the “Saros.”

NASA explained the Saros in a web page titled Eclipses and the Saros, and the unscrupulous flat-Earthers were quick to devise a conspiracy theory. They invented the scenario that NASA —a space agency with billions of dollars of a budget— are somehow using ancient technology to predict the occurrences of an eclipse. They are wrong. NASA does not use the Saros Cycle to predict eclipses.

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Determining the Distance to the Sun from the Transit of Venus

The distance to the Sun was first determined with a good accuracy from worldwide observations of the transit of Venus. A transit of Venus is a phenomenon where Venus passes in front of the Sun. By measuring the time Venus spends crossing in front of the Sun from two or more locations on the surface of the Earth, it is possible to calculate the distance to the Sun.

Flat-Earthers insist that it is impossible to determine the distance to the Sun in the globe model because sun rays are practically parallel. They are wrong. Using simple geometry, the distance to the Sun can be determined from the observations of the transit of Venus.

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Day and Night Areas on a Flat Earth

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At any given time, there is an equal area of the Earth that is experiencing daytime, and that is having a night time. The reason is that the sun is very far, and it would illuminate a hemisphere of the Earth, and leave the other dark.

If we plot which areas of the Earth that are getting sunlight on an azimuthal equidistant map centered on the north pole, the sun would appear to illuminate a somewhat elliptical area during the northern hemisphere summer, and a lopsided Bat-Signal shaped area during the winter. During the equinox, the sun would appear to illuminate a half-circle area.

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The Apparent Size of the Sun

The apparent size of the Sun is practically constant throughout the day. This can only happen if the Sun is practically at the same distance all day.

In the flat-Earth model, the Sun is close to the surface at the distance of about 5000 km (3500 miles). The Sun is supposed to be moving in a circle, and it completes the circling motion once in a day. This fact should cause the Sun’s apparent size to change during the day. But it does not happen. The Sun’s constant apparent size is evidence that the flat-Earth model is wrong, and that the Sun is very far away.

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Total Solar Eclipse, Drawn to Scale

Any diagram showing two or more celestial bodies is almost never drawn in the correct scale. The reason is that in most cases, any two celestial bodies are spaced too far away relative to their sizes. It is just not possible to draw them in the correct scale and still effectively describes what we want to explain. We don’t have much choice other than drawing them not to scale.

The perpetrators of flat-Earth disseminate the allegations that the diagrams were drawn not to scale because of evil intentions, and not because of legitimate technical reasons. Some people don’t understand this and fell victim to flat-Earth indoctrination.

Continue reading “Total Solar Eclipse, Drawn to Scale”

The Galileo Affair was Never About the Shape of the Earth

Flat-Earthers often bring Galileo into the discussion. They treat him as a ‘villain’ who supported the spherical Earth but unable to prove it as he failed to demonstrate the occurrence of stellar parallax.

They are wrong. The Galileo affair was in fact not about the shape of the Earth at all. It was about geocentrism vs. heliocentrism. Everyone involved already knew that the Earth is spherical.

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Fraunhofer Lines

Sunlight can be broken into its constituent colors using a prism. The colors are the optical spectrum of the Sun. They are the same colors on rainbows. On careful observation, the spectrum is not perfectly continuous, but it has dark lines scattered over the entire spectrum. It turned out that from the lines, we can tell the composition of the Sun without physically getting there.

Some flat-Earthers think that it is impossible for us to determine the composition of the Sun, as it is impossible for anyone to visit the Sun without getting roasted in the process. They are wrong. The composition of the Sun can be determined from the spectral lines, or more specifically for the Sun: the Fraunhofer lines.

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Shadow on Clouds

Before sunrise or after sunset, the Sun is below the horizon and not directly visible. But the sky and clouds above are illuminated because they are high above, and sunlight can reach them.

If there’s a mountain between the Sun and the clouds, it can cast a shadow on the clouds. The flat-Earth model assumes the Sun is always high above, and thus, this phenomenon cannot possibly occur in a flat-Earth.

The fact that a mountain can cast its shadow on clouds far above it is evidence that the Earth is spherical.

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The December Solstice, When the Sun Illuminates an Impossible Area in the Flat-Earth Model

The December solstice occurs between the 20th and 22nd in December, which is when the Sun reaches its most southerly excursion. Around this time, the northern hemisphere experiences winter, and conversely, the southern hemisphere experiences summer.

If we try to plot the areas that are having daytime and nighttime on the so-called ‘flat-Earth map,’ the Sun would appear to illuminate an impossible area, similar to Batman’s bat-signal. This fact tells us that the ‘flat-Earth map’ does not conform to reality.

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Observing Mercury and Venus

Mercury and Venus are closer to the Sun compared to the Earth. The best condition to observe these planets is during some time after sunset or before sunrise. In some cases, they are even visible in the day.

Many flat-Earthers think that it should be impossible to observe Mercury & Venus as they are closer to the Sun. They are wrong.

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Sun Glare Makes the Sun Appear Larger

The Sun has the angular size of approximately 0.53° seen from Earth, and it is practically constant throughout a single day. But sunlight is very intense and result in a glare that surrounds the Sun. Because of the intensity, we are unable to distinguish the Sun from its glare.

During a sunset, the intensity of sunlight is lower due to the fact that sunlight has to traverse Earth’s atmosphere at an angle. Because of the reduced intensity, the amount of glare will also be reduced, and the Sun can look as if it is shrinking.

Flat-Earthers often use this phenomenon as ‘evidence’ of a receding Sun during a sunset. They are wrong.

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How the Sun ‘Burns’ Without Air in Space

A candle gets its flame from combustion, a chemical reaction. The hydrocarbon that formed the candle reacts with oxygen, and we get carbon dioxide, water, and heat energy as the results. The oxygen is obtained from the air. If the air supply is cut off —for example by covering the candle with a glass— then the reaction will stop, and the flame goes out.

We hear flat-Earthers often claimed that it is impossible for the Sun to be in space. They said the Sun burns, and therefore it requires oxygen. Space is empty, so it is impossible for the Sun to be there. They are wrong. The reaction that is occurring in the Sun is not combustion. It works differently from what happens with the candle.

Nuclear fusion powers the Sun.  It fuses hydrogen atoms into helium atoms. All the necessary component for the reaction to happen is in the Sun, and the reaction doesn’t require matters from external sources.

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The Eratosthenes Experiment: Proving the Earth is Spherical

In 205 BC, Eratosthenes successfully determined the circumference of the Earth by measuring the length of the shadow cast by a rod. He did the measurement in Alexandria and timed it to coincidence when the Sun is directly overhead Syene.

2222 years after that, some flat-Earthers tried to refute the Eratosthenes experiment. They say the experiment can be applied to the flat-Earth model.

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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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Earthshine Proves the Moon Obscures the Sun During a Total Solar Eclipse

During a total solar eclipse, the Moon is right between the Earth and the Sun. Thus, the near side of the Moon does not receive any sunlight. But while it is dark, it still gets some light reflected by the surface of the Earth. This phenomenon is called Earthshine.

Some flat-Earthers argue that a solar eclipse is not caused by the blocking of the Sun by the Moon, but by another, mysterious celestial body. The reason is that eclipses are incompatible with their beliefs about the motion of the Sun and the Moon.

Earthshine proves that they are wrong.

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The Starburst Effect is not Evidence of CGI

In photography, the starburst effect gives the illusion of light rays from strong light sources in an image. The effect happens when the lens’ aperture is not a perfect circle, and it gets more pronounced under a narrower aperture.

Flat-Earthers often find themselves looking for any peculiarity —no matter how small or unbelievable— to discredit any picture they deem unacceptable to their misguided causes. One of this peculiarity is the starburst effect.

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