Annual Stellar Motion: Evidence of Earth’s Orbit Around the Sun

In each day, we can observe stars drift about 1° in their movement around the celestial pole. In a month, they will appear to have moved about 30° when observed at the same time in the night. And in a year, stars are back to their original positions precisely a year before. This annual stellar motion is the basis for the calendar system we are using.

Some flat-Earthers think we see the same star constellations every night. From this assumption, they would conclude the Earth is stationary. But their claim is demonstrably wrong. Continue reading “Annual Stellar Motion: Evidence of Earth’s Orbit Around the Sun”

Stellar Parallax

Stellar parallax is the apparent shift of the position of any nearby star against the background of distant stars. It is the result of Earth’s orbital motion around the Sun. It is so small and hard to observe. Successful measurement of stellar parallax was done only after the 19th century.

Some flat-Earthers presume as if stellar parallax has not been successfully observed, and use it is ‘evidence’ the Earth is stationary. They are wrong.

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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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The Aether Experiments are Never Evidence of Flat and Stationary Earth

Aether was the hypothetical material that fills the region of space. It was assumed to be the medium that allows light and gravity to propagate in space. Throughout the late 1800s and early 1900s, some experiments were carried out to prove if the aether exists.

Flat-Earthers (and geocentrists alike) often use the results of these experiments to support their case that the Earth is stationary. But they are wrong. These experiments were conducted to prove if the Aether theory, or if one of its competing hypotheses —like the Special Relativity— better explains reality.

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Hot Air Balloon and the Force of Gravity

A hot air balloon rises because it has buoyancy. Buoyancy is the upward force that is exerted on the trapped hot air because its density is lower than the surrounding air. If buoyancy is greater than the force of gravity — or the weight of the balloon—, then the balloon will rise.

The basic physics escape most flat-Earthers. To them, the fact that a hot-air balloon rises is an ‘evidence’ that gravity does not exist. They believe things go up or down because of density. They are wrong.

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The Mockumentary ‘Dark Side of the Moon’

The film ‘Dark Side of the Moon’ is a mockumentary. It is fictional but presented as if it is a real documentary. The film features guests like Donald Rumsfield, Henry Kissinger, Alexander Haig, Vernon Walters, Buzz Aldrin, and Stanley Kubrick’s wife. In the film, they all pretend that the Moon landings were faked, and created in a studio by Stanley Kubrick.

There are many doctored versions of the film circulated on the Internet. Usually, the ‘giveaways’ are cut to make the film more believable. Then, the film is presented as ‘evidence’ that the Moon landings did not happen. Unfortunately, many believe these edited versions of the film and don’t realize the events in the movie are entirely fictional.

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Antarctic Ice Domes: Not The Dome That is Supposedly Enclosing the Earth

An ice dome is one of many forms a glacier can take. It is an upright ice surface in the higher altitude portions of an ice cap or an ice sheet. There are many such features found on icy terrain. And Antarctica is no exception.

When an ice dome gets mentioned, flat-Earthers often confuse it with the mythical dome enclosing the Earth as described in most flat Earth model. No such dome actually exists.

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The Oblate Spheroid Shape and Pictures of the Earth From Space

The Earth is not perfectly spherical. Its diameter is longer across the equator than between the poles; it is oblate spheroid. This fact is often questioned by flat-Earthers. According to them, every picture of the Earth from space shows the Earth as a perfect sphere, and never as an oblate spheroid. Then they would present it as ‘evidence’ that scientists have been lying to us.

But it is actually possible to determine that the Earth is in fact oblate spheroid from pictures of the Earth taken from space.

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Difference in Entrance Pupil Diameter: The Real Reason Why An Obscured Object Appears When Zoomed In

Ever seen a video where a flat-Earther tries to demonstrate that a distant object that appears to be behind an obstacle can be brought back into view simply by zooming in? He would then conclude the same thing would happen when zooming in to a distant ship, and the reason a distant ship is not visible is not the curvature of the Earth.

Well, no. The real reason why the object in that experiment can be seen after zooming in is that the obstacle is close, and there’s difference in the camera’s entrance pupil size when the zoom changes. For a camera that has very long zoom range —like the Nikon P900—, the difference can be very dramatic.

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Polaris: Our Current North Pole Star, But Not For Forever

Flat-Earthers often claim that the fact Polaris not appearing to move is ‘evidence’ that the Earth is flat and stationary. If the Earth is a rotating sphere, then Polaris —as they say— should appear to be in motion.

In reality, Polaris is indeed moving across the sky. Though it is not something we can observe in a single night, or even in our entire lifetime.

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The topic of tide come up frequently in the flat-Earth community. Let’s examine some of the ‘issues’ they brought up about tides in Q&A format.

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Polar Circumnavigation

Flat-Earthers think there hasn’t been anyone who has circumnavigated the Earth by traversing both the north pole and south pole in the process. All we have are explorers who have circumnavigated the Earth to the east or west, parallel to the equator; explorers like James Cook or Ferdinand Magellan. They don’t really have the choice, because if polar circumnavigation is possible, then the flat-Earth assumption falls flat.

But, like a lot of assumption in the flat-Earth community, it is simply not true. There are in fact many people who have done a polar circumnavigation, and the information can be easily found on the Internet.

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