An Easy Experiment to Debunk the Flat Earth by Observing the Size of the Sun

Svartbjørn said:

Sounds to me like he's saying that at a 90 degree angle from the disk, the Sun is 3k Miles from the surface. For the sun to remain the same size it must either A) Increase its speed from horizontal, to vertical, to horizontal or B) the sun must get SUPER close to the earth in the morning and evening and SUPER far away at noon. If it didnt do one of these things, the perspective would change, the sun's size would change and theyd have to find another explanation with the given that this is occurring on a disk world.

Not exactly what I'm trying to say. it's from the point of distance between the earth and sun rather than from the size of the sun. If the FE sun follows the same path of the heliocentric sun and goes down below the horizon, how is it maintaining a 3000 mile distance from the earth if it's moving parallel to it? That's why I said either the sun has gotten very, very close to the flat earth or it's a huge downward curve or a very fast slope. It should also have much more of a horizontal arc. Does this make sense to anyone?

Reference this video:

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Not exactly what I'm trying to say. it's from the point of distance between the earth and sun rather than from the size of the sun. If the FE sun follows the same path of the heliocentric sun and goes down below the horizon, how is it maintaining a 3000 mile distance from the earth if it's moving parallel to it? That's why I said either the sun has gotten very, very close to the flat earth or it's a huge downward curve or a very fast slope. It should also have much more of a horizontal arc. Does this make sense to anyone?

Of course not. They are just claiming some odd interpretation of "perspective", or "something".

But this thread is about the SIZE of the sun, not the position.

Does this make sense to anyone?
It makes sense in the way that I can understand what he's trying to say, and also understand why his explanation seems reasonable to him.

And, at the same time, it makes no sense as a valid explanation, and we can use his picture to illustrate this:

Let's say the distance from the guy to the end of the wall is 25 metres, and that those 25 metres are equivalent to the 25,000-mile diameter of the diskworld (the maximum distance one could be from the sun).

It looks like there are about 8 vertical batons along the length of the wall - which makes them spaced about 3 metres apart - and that spacing is roughly equivalent to between 4 and 6 horizontal batons (let's use 4, to give the flat earth maximum chance).

On this scale model, therefore, the sun would be about 4 batons (3 metres/3,000 miles) above the yellow line, and even at the far end of the diskworld, using perspective, would still be clearly visible.

Or, to put it briefly: place the sun on the horizontal strip of your choice, and notice that it's still completely visible, and at an angle that could be trigonometrically predicted, at the far end of the picture.

The side-on picture is correct. So is the perspective illustration.

But what he's done, by combining the two (at 3:24), is wrong. And we could see this using his own picture, by forming a triangle between his observer, the other end of the yellow line, and the other end of one of the batons above the yellow line.

We know that that "side-on" triangle would be accurate, as far as angles and lengths go. But we can also see that superimposing it over the real-life picture that it's taken from wouldn't work at all.

He also says that the sun would continue to go down beyond the horizon/vanishing point, and ignores the most salient point, as has been mentioned before, that his sun should be steadily shrinking to nothing - as his horizontal batons do - which we clearly don't see in reality (when the sun is viewed properly, through something which shows its actual size by masking the solar flare).

It really seems to me like one of those 'explanations' that's "not even wrong".

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Ok, I'll only post regarding the size of the sun.

He also says that the sun would continue to go down beyond the horizon/vanishing point, and ignores the most salient point, as has been mentioned before, that his sun should be shrinking to nothing - as his vertical batons do - which we clearly don't see in reality.

Some of the videos do claim it shrinks, but it's clear that what they're seeing is the lessening of the bleed out on their camera because the Sun is getting dimmer as it sets and the line of sight is obscured by more atmosphere, clouds, etc. That's why pictures like Mick's of the Sun through filters that show the size of the disk at sunset and high in the sky put the lie to that.

That's why pictures like Mick's of the Sun through filters that show the size of the disk at sunset and high in the sky put the lie to that.

Video too. I took this with my P900 and a solar filter.

The sun is the same size and shape throughout. (although my local horizon is up a bit, due to hills)

Video too. I took this with my P900 and a solar filter.

Very nice. And for those who don't have a solar filter, they could make the same video of the Moon. However, it's not clear to me what Flat Earther's think the Moon really is, so who knows what to expect it's size to do as it moves through the sky.

In the absence of a solar filter, a cheap piece of welder's glass or goggles will suffice. It's not quite as good, you'd lose all the cloud details that you can see in Mick's video, but I've used it for taking pictures of eclipses a coupe times.

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In the absence of a solar filter, a cheap piece of welder's glass or goggles will suffice. It's not quite as good, you'd lose all the cloud details that you can see in Mick's video, but I've used it for taking pictures of eclipses a coupe times.

Even cheaper than welder's glass, and much better images:

I'm hoping the August 21 2107 eclipse (in just two months) will prompt more people to examine the sun. It's going to be a pretty huge event in the US. There will be millions of solar viewers and camera filters purchased. A turning point in popular solar photography.

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Rory, I'm still reading through your respond so I can understand it. LOL....

LOL....thanks for the avatar....

Rory, I'm still reading through your response so I can understand it.
When you get down to it, a big part of your question seems to be, "Why can't we superimpose a profile onto a perspective?"

To illustrate, let's consider a railroad track - using something from 'real life', as the video says - wherein the ties are spaced approximately 49.5cm apart, and the tracks 1.44m apart. I'll flip the image, so it matches more closely the original diagram, and place an observer and a sun on it, like so:

(That's supposed to be an eye. )

Now, because we know the real life measurements, we can draw the side on version of what we're seeing in reality:

Clearly, the "side-on" view of the tracks cannot be superimposed onto the "perspective" view and be expected to 'line up'.

How is [the flat earth sun] maintaining a 3000-mile distance from the earth if it's moving parallel to it?
It's not. It isn't real. It doesn't work.

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That's reality, Rory. You can't superimpose a side on view with an angled view of perspective. I know their will be some perspective on a side on view the further to the right or left the sun gets, but your not doing to get an arc when the sun is moving parallel.

I believe the only part I couldn't quite grasp was drawing a triangle.

The sun will still have an angle of view of 88° at 100 miles away.

I believe the only part I couldn't quite grasp was drawing a triangle.
Drawing a triangle like this one:

That's what your man in the video has put forward, trying to say the angle we measure should actually be the one to the 'green' sun, when we know that, in drawing a diagram in profile, perspective doesn't come into it.

(Imagine the photographer of this picture moving so that he was facing the fence/wall/slats 'straight on': the location of the green circle would then correspond with the altitude of the two yellow circles, and the angle would be correct.)

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Makes a lot of sense.

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