NASA and Other Space Agencies

There are many space agencies from multiple countries. Some are from countries that are rivals or even enemies at some point in history. Even so, practically all their findings corroborate each other. Any made up claims or fabrications would have been noticeable and found very quickly.

Flat-Earthers accuse NASA of being part of the so-called globe Earth conspiracy, with the purpose of spreading “globe Earth propaganda” to the world population. However, there other space agencies, which are independent and employ thousands of staffs. And every one of them practically confirms NASA’s findings.

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Variability of Atmospheric Refraction

In most situations, atmospheric refraction bends light downwards and causes objects to appear higher than they actually are. The strength of atmospheric refraction is not constant. It depends on weather condition and varies on the different seasons, different days, and even different times of the day.

Because of the variability of atmospheric refraction, a distant object that is usually obstructed by Earth’s curvature can sometimes be visible. Some flat-Earthers would cherry-pick moments when the object is visible. They would show such specific moments to everyone and use them to “disprove” Earth’s curvature; happily ignoring the cases where Earth’s curvature partly or entirely obstructs the object.

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Fiber-Optic vs Satellite Communication

Fiber-optic communication is a method of transmitting data by sending pulses of light through an optical fiber. These days, the majority of data communication involves a fiber-optic connection. However, other methods of transmitting data exist, including satellites.

Flat-Earthers use the prominence of fiber-optic communication as “proof” of the nonexistence of satellites. Such a line of thinking is a fallacy of hasty generalization. Using the same “logic,” we can “prove” trains don’t exist just by showing the existence of cars.

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Panorama Images and Horizon’s Curvature

A panorama image is stitched from multiple photos that were taken from different angles, forming a very wide field of view, even 360°×180°, covering every possible angle from the viewer.

Someone has taken a panorama from a high-altitude balloon and made available the results in various projections. Flat-Earthers saw a flat horizon in one of the panorama images and took the wrong conclusion. The horizon will appear flat in a cylindrical or equirectangular projection due to an effect of the projection. The panorama creator also has the panorama in other formats, including an interactive one in the general perspective projection, which shows how it would look from a human eye, and it shows the curvature.

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The Space Protest by ASAN That Was Hijacked by Flat-Earthers for Provocation

In 2017, the group who name themselves ‘ASAN’ staged a protest to Donald Trump by sending a high-altitude balloon carrying a camera and a crude message, which was quoted from a statement by Edgar Mitchell, an astronaut from the Apollo 14 mission.

Some unscrupulous flat-Earthers hijacked the protest and turned it as if ASAN did it to prove Earth’s curvature and to insult them. These flat-Earthers pointed out that ASAN somehow “forgot” to conceal the fact that a fisheye lens was used. In reality, it is never the intention of ASAN to prove Earth’s curvature, nor to throw insults to flat-Earthers.

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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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Frame of Reference

A frame of reference consists of an abstract coordinate system and the set of physical reference points that uniquely fix the coordinate system and standardize measurements. Speed or velocity is relative to a frame of reference. It is possible that two speeds/velocities are measured relative to a different frame of reference and thus cannot be directly compared.

Flat-Earthers would often compare two different speed measurements like an airplane moving at 900 km/h (560 mph) and Earth’s surface near the equator at 1674 km/h (1040 mph). They would conclude the airplane should not be able to catch up with Earth’s surface and would not be able to land if the Earth is rotating. They are wrong. The speeds are measured relative to the different frame of reference, and therefore, cannot be compared directly.

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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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Old Star Charts and Earth’s Axial Precession

Due to Earth’s axial precession, the positions of Earth’s celestial poles shift gradually in a cycle of approximately 26000 years. These days, Polaris is very close to the north celestial pole. However, 2000 years ago, Kochab is much closer to the celestial pole than Polaris. In the next 2000 years, Errai will replace Polaris as our pole star.

Flat-Earthers claim that the stars are always in the same position proves the Earth is stationary. They are wrong. By observing old star charts from a few centuries ago, the shift of celestial poles can be determined. It proves stars are not always in the same position as today, and that the Earth is rotating.

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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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Composite Photos of the Earth

NASA has published several pictures of the Earth that are composites. It means the pictures were the result of combining many images into a single picture. In most cases, the source pictures were taken from low-orbiting satellites to obtain higher resolution pictures of the Earth.

Flat-Earthers discovered the photos are composites and claimed to have exposed “yet another evidence” of wrongdoing. They would publish this “findings” everywhere to turn us emotional. They are wrong. Nobody is covering the fact the pictures are composites, and there is no intention to deceive. Information that the photos are composites can be readily found in NASA’s website, far before the claimed “discovery” by flat-Earthers.

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Range Estimation Using the Distance to the Horizon

Sailors sometimes need to estimate the range of a distant contact. Without radars, the only readily available reference point for estimating ranges is the horizon.

By knowing the height of the observer from the waterline, it is possible to calculate the distance to the horizon, and thus, it is possible to determine the distance to a remote contact, relative to the horizon. It is possible to do this only because the Earth is spherical.

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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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Photographic Exposure

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In photography, exposure is the amount of light reaching the camera film or sensor, as determined by shutter speed, lens aperture, and scene luminance. By adjusting the exposure and sensor/film sensitivity (ISO), it is possible to get a bright or dark result.

It is quite apparent that photography has never been any flat-Earthers’ strongest point. There are many misconceptions in flat-Earth circles that arise from their ignorance about photography. One of such misconceptions is exposure.

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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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Determining the Visibility of a Star From Its Declination and the Observer’s Latitude

We can determine if a star is visible from a specific location using the declination of the star and the latitude of the observer, subject to other conditions like observer’s topology, the magnitude of the star, weather conditions, etc. It is possible to do this because Earth is a rotating sphere.

If the Earth is flat, every star would have been visible all night from every location. We don’t see the same stars every night because some of them are below the horizon and obscured by the Earth.

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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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Theories of Gravity

Gravity is a natural phenomenon by which all things with mass or energy are brought toward one another. Today, the phenomenon of gravity is explained by two theories: Newton’s law of universal gravitation and Einstein’s general relativity.

Flat-Earthers take the existence of the two explanations as inconsistency in science and use it as a “proof” of deliberate misconduct. Such allegation is obviously only a result of their prejudice. The two theories are the correct explanations of gravity, and can reliably predict the outcome of the phenomenon.

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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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