Missions to the Moon, Post-Apollo

After the Apollo moon landings, we continue launching missions to the moon, but with uncrewed spacecraft. The Apollo program was not entirely a scientific mission. It also served as a political mission due to the Cold War. We can research a lot of things about the moon without risking human lives by sending them to the moon.

Flat-Earthers claim that there have not been any missions to the moon after the Apollo missions, and they conclude that the Apollo missions were fabricated. In reality, we continue sending spacecraft to the moon to this day.

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Angular Resolution

Angular resolution is the minimum separation between distinguishable features in an image. Objects smaller than the angular resolution are indiscernible in the picture. The theoretical maximum angular resolution is determined by the diameter of the aperture of the optical instrument.

Flat-Earthers like to demand images of the lunar landers taken with a telescope as proof that the Apollo Moon landings did occur. In reality, no optical telescope on Earth is large enough to resolve the landers.

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Sweden Solar System

The Sweden Solar System is the largest scale model of the Solar System in the world. We can use it to get a better sense of the sizes and distances in the Solar System.

Flat-Earthers like to claim that we never see a scale model of the Solar System, and use it to “prove” the failure of science to explain the world. The Sweden Solar System proves them wrong, and also gives us an idea about the problem of making a scale model of the Solar System.

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Geometry of a Crescent Moon

Some people are confused that the crescent moon can be visible at night, even though during the time, the Moon is closer to the Sun than Earth, and the part of the Earth is facing away from the Sun.

Many flat-Earthers have the same visualization difficulties, but they take it a step further and use it as ‘evidence’ as a ‘failure’ of science to explain the fact. In reality, the phenomenon can be readily explained in the spherical Earth model.

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The Moon and Stars in a Single Picture

Stars are not visible in photos of the Moon –including those taken from the lunar surface— because the Moon is sunlit. The exposure needed to take a photograph of the Moon is not that much different from that used to take a photo in daylight on Earth’s surface.

To demonstrate this, we can try taking a picture of the Moon with stars visible, on the conditions: 1. The lunar features, like the craters, are correctly exposed, not overexposed. 2. Taken in a single exposure, not HDR, and not the result of editing. Even if we are using the best camera available today, the stars can’t show up in large enough quantity.

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Visual Albedo of the Moon and the Earth

Visual albedo is the measure of the reflection of solar radiation out of the total solar radiation received by an astronomical body, taking into account only the visible light. The visual albedo of the Earth is 0.37, and the Moon’s is 0.12.

The Moon appears darker if the Earth also appears in the same photograph. Flat Earthers use the fact to “prove” that the picture is fake. They are wrong. The Moon appears darker because it reflects less sunlight than the Earth.

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Lunar Phase: Earth’s Shadow has Nothing to do with It

It can be surprising that many people believe that the lunar phase is caused by the Earth casting its shadow on the surface of the Moon. Flat-Earthers are no exception. But they take it one step further and use the misconception do “disprove” the fact that Earth is a sphere. They are wrong. The lunar phase is the shape of the sunlit part of the Moon seen from the observer.

On the other hand, the phenomenon where the Earth casting its shadow on the surface of the Moon is called the lunar eclipse. Moon phase occurs all the time and undergoes a monthly cycle, while a lunar eclipse happens only a couple times in a year.

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The Varying Earth-Moon Proportions in Different Pictures

How an object appears in a photograph depends on perspective —the position of the camera relative to the object—, and field of view of the camera. The farther the object, the smaller the object will appear in the resulting image; and conversely, the closer the object, the larger it will appear. The narrower the field of view, the larger the object will appear in the image; and conversely the wider the field of view, the smaller the object will appear.

Flat-Earthers take the varying proportions of the Earth & Moon in different pictures as a glaring inconsistency. They are wrong. The pictures were simply taken from a different perspective and field of view.

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The Apparent Size of the Moon

The apparent size of the Moon remains constant in a single day. This can only happen if the Moon is practically at the same distance all day.

In the flat-Earth model, the Moon is thought to be moving in a circle above the flat Earth. Such a notion should cause the Moon apparent size to vary in a day. However, in reality, the Moon appears in the same size all day, and it proves that the flat-Earth model does not represent reality and that the Moon is much farther.

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Chang’e 4 and the Confusion About the Dark Side vs Far Side of the Moon

China’s Chang’e 4 spacecraft has successfully landed on the Moon. It is the first ever spacecraft to land on the far side of the Moon.

Unfortunately, some news outlets used the term “dark side of the Moon” which is inaccurate. The side of the Moon where Chang’e 4 landed is not always dark, but instead always facing away from the Earth. That part of the Moon has the same day and night cycle like the side that is facing us and is not always dark.

Flat-Earthers were confused that the spacecraft use solar panels. If the side of the Moon is always dark, then it should be pointless to use solar panels. They took these facts as “proof” of some sort of misconduct. They were simply confused about the term some news outlets were using. The correct term is “far side of the Moon.”

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Tycho Crater

The Tycho Crater is a crater on the Moon having the diameter of 85 km (53 miles). It is too small to recognize using the naked eye. However, it lies on a bright colored highland that can be mistaken as the crater itself. The crater also has an extensive ray system, which was from the ejected materials when the crater was formed.

Flat-Earthers claimed the visibility of the Tycho Crater proves the Moon is not that far. They are wrong. We cannot see the Tycho Crater using the naked eye. What is visible is the highland it lies on or its extensive ray system.

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Sunlit Objects and Visibility of Stars

Generally, sunlit objects are far brighter than any stars. It is the reason stars are not visible in a lot of photographs showing sunlit objects unless the objects are overexposed and made much brighter than the correct exposure.

Flat-Earthers take the lack of stars in photographs as evidence of misconduct. They are wrong. If the primary object in the picture is sunlit, then in most cases, stars will not be visible.

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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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Lunar Libration

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The Moon is tidally locked. Half of the Moon is always facing the Earth. However, due to libration, we can take a glimpse of areas of the moon that are not always visible.

Flat-Earthers invented many “scenarios” to “explain” how the so many lunar-related phenomena can happen on the flat Earth model. Some of these “explanations” include “transparent Moon”, “hemisphere-shaped Moon”, “flat circular Moon”, etc. Lunar libration rules out the majority, if not all, of these “explanations.”

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Stellarium

Some flat-Earthers like to observe celestial phenomena and the positions of celestial objects. Sometimes, they insist such events cannot possibly happen if the Earth is a sphere orbiting the Sun, and took the wrong conclusion that the Earth must be flat.

We can try asking them the time of the occurrence and the position of the observer, then use Stellarium or similar applications to simulate it. If the result matches the observation, then they have nothing to complain about. Their confusion was only the result of their ignorance.

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Lunar Craters

At any time, the Sun illuminates one half of the Moon and the other half dark. The phase of the Moon is the shape of the sunlit portion of the Moon as viewed by observers on Earth.

The phase of the Moon can never be adequately explained using the flat Earth model. To deal with this inconsistency in their theory, some perpetrators of flat Earth invented an ‘explanation’ that the phase of the Moon is not caused by sunlight. They are wrong. We can observe the Moon very carefully using telescopes of high-zoom cameras, and it will be evident how the lunar craters are lit. And this can only happen if the Moon is sunlit.

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Illuminated Fraction of a Full Moon

A lunar eclipse does not happen every month because the orbit of the Moon is tilted 5.145° to Earth’s orbit around the Sun. And thus, the Earth does not always cast its shadow on the Moon during maximum opposition. Instead, a full moon occurs.

Some flat-Earthers take this as ‘evidence’ that a full moon cannot possibly happen because the geometry does not allow for a 100% illuminated Moon. They are wrong. In reality, a full moon is never 100% illuminated.

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Geometry of a Full Moon

Some people are confused that a full moon is visible all night, and think if the full moon is the result of the opposition of the moon from the sun, then a full moon should be visible only at midnight.

Flat-Earthers who have such spatial visualization problem take a step further and use it as ‘evidence’ that the Earth is not a sphere. They are wrong. The full moon phenomenon can easily be explained in the spherical Earth model.

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