The Flat Earth Society
Flat Earth Discussion Boards => Flat Earth Theory => Topic started by: Bobby Shafto on December 15, 2018, 06:24:56 PM
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(http://i65.tinypic.com/a4vnm8.jpg)
Westward view from Mt Woodson in San Diego County on 12/13 @ 0641 PST.
This is different from the underside of clouds being illuminated by a sun "below" the horizon. Here, we're looking in the opposite direction of sunrise and seeing illumination of low altitude atmosphere before the sun has appeared to the east.
I believe this is the antisolar line. I believe this to be another sun-related phenomenon that could be a discriminator between a flat and globe earth.
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That's an incredible shot.
So we're looking at a glow at the western horizon from a pre eastern sunrise? Meaning you can't actually see the sun rising to the east due to it still being bellow the curvature of the earth, or in the case of from San Diego, the Laguna Mts being the horizon? Interesting.
What are you suggesting is the cause of this glow,this lighting phenomena, or are you asking? The question is quite intriguing.
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That's an incredible shot.
So we're looking at a glow at the western horizon from a pre eastern sunrise? Meaning you can't actually see the sun rising to the east due to it still being bellow the curvature of the earth, or in the case of from San Diego, the Laguna Mts being the horizon? Interesting.
What are you suggesting is the cause of this glow,this lighting phenomena, or are you asking? The question is quite intriguing.
That image was 1 minute before astronomical sunrise. Camera height on antenna mast is around 2000' MSL. The Cuyamaca range to the east (just west of the Lagunas) create the artificial elevated horizon that delays sunrise a little for the basin of San Diego. So, yes, San Diego (and the Woodson peak) were still in shadow, minutes before the sun would rise over the Cuyamacas.
To the west, a surface layer haze, trapped by a temperature inversion, extends up to around 1000' anywhere from 10 to 25 miles off shore. This is what is catching the rising sun's first rays while land and coast to the east are still in shadow.
The peninsular mountain ranges east of San Diego could be the source of shadow and why low elevation haze to the west is glowing while elevations closer but lower to the Cuyamacas are still in twilight. However, there are no mountains to the west and yet the same anti-solar glow sometimes occurs to the east at sunset.
My conclusion is it's a feature of a globe earth, but I offer it up for discussion.
(I'll see if I can find a comparable eastern glow during sunset photo.)
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Thanks for the in depth explanation. I now the landscape and geography well as I spent the better part of 45edit(54 years) years in San Diego.
I also enjoy your La Jolla to Carlsbad threads.
Some points of interest to further your investigations and experiments I suggest Cuyamaca and Laguna lookout points to the east towards the Salten Sea. Should give you really good perspective of distance and elevation, line of sight etc. and some really good sunrise shots.
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It's a phenomenon known as alpenglow. It's fairly common in mountain areas in the "blue hour" before sunrise or after sunset.
Alpenglow (from German: Alpenglühen, Italian: Enrosadira) is an optical phenomenon that appears as a horizontal reddish glow near the horizon opposite of the Sun when the solar disk is just below the horizon. This effect is easily visible when mountains are illuminated, but can also be seen when clouds are lit through backscatter.
Since the sun is below the horizon, there is no direct path for the sunlight to reach the mountain. Unlike sunrise or sunset, the light that causes alpenglow is reflected off airborne precipitation, ice crystals, or particulates in the lower atmosphere. These conditions differentiate between a normal sunrise or sunset, and alpenglow.
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Cool. Thanks. I'd heard of that but didn't think that might be applicable here.
I'm going to bounce that off of a meteorological expert just to be sure.
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I took this with my phone while driving east on I-8 (Mission Valley) September 17th, 6 minutes after sunset:
(http://i66.tinypic.com/31620jp.jpg)
Alpenglow?
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Alpine Glow. I have some great pictures of this phenomena over Mt Shasta from Lake Shastina, which is about 10 to 15 mile as a crow flies. Not sure it's te same thing as what your photos show but maybe the same principle. I wont share my private pics but here's some links to some that show the same things
https://mysteriousuniverse.org/2015/08/the-mystical-mysteries-of-mt-shasta/
https://www.123rf.com/photo_74550901_mt-shasta-northern-sunset--sunset-over-mt-shasta.html
And this more describes Alpenglow and it seems to refer mountains, snow and clouds to be responsible as well as atmosphere as we're seeing in your pics.
https://digital-photography-school.com/what-is-alpenglow/
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The sun is higher above the horizon when you are higher in altitude. That part of the atmosphere can see the redness of the sunset, and the part below it cannot.
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The sun is higher above the horizon when you are higher in altitude. That part of the atmosphere can see the redness of the sunset, and the part below it cannot.
That's what I thought too. And the reason why "the part below cannot" on a globe is curvature. What's the reason on a flat earth?
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The answer for the perspective explanation is that when you increase your altitude you are broadening your perspective lines, can see further, and it will take longer for the sun to set into your horizon. That part of the sky is seeing the sunset slightly higher, since that part of the sky is higher in altitude.
The explanation for EAT is that the sun's ray's are barely missing the earth and are hitting the red area of the horizon.
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The answer for the perspective explanation is that when you increase your altitude you are broadening your perspective lines, can see further, and it will take longer for the sun to set into your horizon. That part of the sky is seeing the sunset slightly higher, since that part of the sky is higher in altitude.
The explanation for EAT is that the sun's ray's are barely missing the earth and are hitting the red area of the horizon.
But on a flat earth with the sun always at 3.000 up from the surface of the earth, how does it get close to the horizon? Because there is no red areas unless the sun is near the horizon.
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The answer for the perspective explanation is that when you increase your altitude you are broadening your perspective lines, can see further, and it will take longer for the sun to set into your horizon. That part of the sky is seeing the sunset slightly higher, since that part of the sky is higher in altitude.
The explanation for EAT is that the sun's ray's are barely missing the earth and are hitting the red area of the horizon.
But on a flat earth with the sun always at 3.000 up from the surface of the earth, how does it get close to the horizon? Because there is no red areas unless the sun is near the horizon.
For that part of the sky the sun is near the horizon.
I am not sure what you are asking, exactly. The explanations would either be setting by perspective or EAT. For perspective the idea that the perspective lines would approach each other for infinity without meeting is disputed.
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The answer for the perspective explanation is that when you increase your altitude you are broadening your perspective lines, can see further, and it will take longer for the sun to set into your horizon. That part of the sky is seeing the sunset slightly higher, since that part of the sky is higher in altitude.
The explanation for EAT is that the sun's ray's are barely missing the earth and are hitting the red area of the horizon.
But on a flat earth with the sun always at 3.000 up from the surface of the earth, how does it get close to the horizon? Because there is no red areas unless the sun is near the horizon.
For that part of the sky the sun is near the horizon.
I am not sure what you are asking, exactly. The explanations would either be setting by perspective or EAT. For perspective the idea that the perspective lines would approach each other for infinity is disputed.
How does it set by perspective?
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The same way railroad tracks seem to meet each other, for all intents, in a railroad perspective scene.
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The same way railroad tracks seem to meet each other, for all intents, in a railroad perspective scene.
You mean by perspective it appears to shrink the further away it gets? But the sun doesn't appear to shrink. And the horizon is only miles away if we're looking out over the ocean. Why doesn't the sun shrink like everything else does as it gets farther away?
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Read here: https://wiki.tfes.org/Magnification_of_the_Sun_at_Sunset
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The answer for the perspective explanation is that when you increase your altitude you are broadening your perspective lines, can see further, and it will take longer for the sun to set into your horizon. That part of the sky is seeing the sunset slightly higher, since that part of the sky is higher in altitude.
The explanation for EAT is that the sun's ray's are barely missing the earth and are hitting the red area of the horizon.
Which is it? Can't be both. EAT at least makes sense. Perspective doesn't.
As with the underlit clouds topic. Perspective can't do what you ascribe to it. And it's even more impossible with this phenomenon.
Now, if you're on board the EAT train, that's another story and that's where a flat earth model could focus to contest globe curvature. But then it'd just be a counter and not a better explanation. The key is in how to distinguish between Flat+EAT and Globe curvature.
But Perspective is no good.
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Read here: https://wiki.tfes.org/Magnification_of_the_Sun_at_Sunset
The sun remains the same size as it recedes into the distance due to a known magnification effect caused by the intense rays of light passing through the strata of the atmolayer.
So the farther away it get this magnification effect makes it look larger. But it's not in the strata of the atmolayer or anywhere near the atmosphere, it's 3,000 mile up. And this doesn't happen to anything else on earth. Why just the moon and sun? Could you be mistaken about what you're really seeing?
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A sun 700 miles or 3000 miles over a flat earth can never get to a zero degree angle of elevation given the distances on earth. Perspective can't cheat geometry.
Perspective is the result of geometry. The only way for a receding sun that is forever above the plane of a flat earth at the altitude FET models claim to be in line of sight with a horizon is for its light to bend upward.
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A sun 700 miles or 3000 miles over a flat earth can never get to a zero degree angle of elevation given the distances on earth. Perspective can't cheat geometry.
Perspective is the result of geometry. The only way for a receding sun that is forever above the plane of a flat earth at the altitude FET models claim to be in line of sight with a horizon is for its light to bend upward.
Is that 700 miles in the distance and 3,000 miles up. Where do we get the 700 mile figure?
Also just how much magnification would be needed for a 32 mile across sun or moon to look as big as they do over head?
But back to your original pics of the sun rise to the east illuminating the horizon to the west. I wounder if that would even be possible on a flat earth with a light source only 32 mils across thousands of miles away. I'm thinking maybe 10,000 miles? It is supposed to be up 3,000 miles though, So just some more questions. ???
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Space isn't even euclidean in RET. General Relativity postulates non-euclidean space.
What geometry are you referring to?
Euclid never proved that the perspective lines approached each other for all infinity without meeting. That is just something we were taught in school.
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Is that 700 miles in the distance and 3,000 miles up. Where do we get the 700 mile figure?
From disparate flat earth models. It depends on who you talk to. The flat earth sun could be anywhere from 700 or so miles to 3000 miles over the earth. I'm just allowing for the variance.
Now, someone on this board has championed a model with a sun much closer than 700 miles. I'm not including that because such a sun could, conceivably, merge via "perspective" with a horizon with the amount of lateral distance available over a flat earth. But if there's any orthodoxy to FET, a sun that close would be quite unorthodox. I'm trying to stick with the mainstream.
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Space isn't even euclidean in RET. General Relativity postulates non-euclidean space.
You shan't draw me into that red herring.
For sun light passing through the space of earth's environment, Euclidean is good enough as far as "RET" is concerned.
What geometry are you talking about?
Euclidean (planar) geometry.
Euclid never proved that the perspective lines approached each other for all infinity without meeting. That is just something you were taught in school.
It's zetetic. I've never seen parallel lines meet in reality. Only illusory. Train tracks may appear to merge, but they don't really. If the sun "sets" because of perspective, it doesn't mean it physically sets. It only appears to do so. The sun would still be X miles above the earth.
But in order for a 3000 mile high sun to appear to merge with a horizon at < 1 degree angle of elevation, you'd need over 170,000 miles of horizontal flat earth surface. Do you have that? That's what you need for perspective to get the sun at a low enough angle to produce the phenomena you say it does.
Perspective is the result of the geometry of depth being translated to a 2D surface, like your retina or a flat canvas or your computer screen. It's not some geometry-defying magic trick that solves the flat earth spatial problem of how the sun (or moon) reaches the horizon and is able to light up the opposite horizon or the underside of clouds.
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It's zetetic. I've never seen parallel lines meet in reality. Only illusory. Train tracks may appear to merge, but they don't really. If the sun "sets" because of perspective, it doesn't mean it physically sets. It only appears to do so. The sun would still be X miles above the earth.
Zetetic. You are correct. The train tracks don't really meet. It's an illusion. The sun doesn't really crash into the earth or the atmosphere. It's an illusion.
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Is that 700 miles in the distance and 3,000 miles up. Where do we get the 700 mile figure?
From disparate flat earth models. It depends on who you talk to. The flat earth sun could be anywhere from 700 or so miles to 3000 miles over the earth. I'm just allowing for the variance.
Now, someone on this board has championed a model with a sun much closer than 700 miles. I'm not including that because such a sun could, conceivably, merge via "perspective" with a horizon with the amount of lateral distance available over a flat earth. But if there's any orthodoxy to FET, a sun that close would be quite unorthodox. I'm trying to stick with the mainstream.
OK Thanks.
I have another question. Is there anything in FES wiki the pinpoints the distance between point A, where the sun is and point B, where it will be 12 hrs later at it's half way point of it's cycle on the FET? Point A to Point B in a straight line.
This would help in some calculations like for example your pic in San Diego. If you could determine the distance the sun was at it's appearance,(sunrise) from a point in San Diego. Then the distance the illuminated horizon was to the west.
Also I would like to point out that the effect you described of the San Diego mountains shadowing the rising sun across San Diego county out into the ocean and lighting up the horizon is the same effect of the rising shadow shown on Mt Everest, just opposite.
You could easily do the calculations because you know the elevation of Laguna and Cuyamaca and the distance the peaks are from down town San Diego.
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It's zetetic. I've never seen parallel lines meet in reality. Only illusory. Train tracks may appear to merge, but they don't really. If the sun "sets" because of perspective, it doesn't mean it physically sets. It only appears to do so. The sun would still be X miles above the earth.
Zetetic. You are correct. The train tracks don't really meet. It's an illusion. The sun doesn't really crash into the earth or the atmosphere. It's an illusion.
An illusion to the eye cannot produce a physical effect on an opposite horizon. That is the point I've been trying to convey to you. If the sun is not really at a low angle but only appears to be because it's an illusion, then it won't be able to do the things that it can only do if it is actually at a low angle.
On a globe it actually IS at that low angle (though not crashing into the earth or the atmosphere, as you put it.).
On a flat earth, it can't be illusory because the physical phenomena is real. The light from the sun must somehow actually be grazing the earth at a low angle. That's why EAT makes more sense than "perspective" if the earth is flat.
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OK Thanks.
I have another question. Is there anything in FES wiki the pinpoints the distance between point A, where the sun is and point B, where it will be 12 hrs later at it's half way point of it's cycle on the FET? Point A to Point B in a straight line.
I don't know. I don't think so. I haven't seen any objections to TimeandDate as a source for where the sun actually is overhead at any given time.
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OK Thanks.
I have another question. Is there anything in FES wiki the pinpoints the distance between point A, where the sun is and point B, where it will be 12 hrs later at it's half way point of it's cycle on the FET? Point A to Point B in a straight line.
I don't know. I don't think so. I haven't seen any objections to TimeandDate as a source for where the sun actually is overhead at any given time.
It must be another on of those areas they leave vague so we can't make accurate calculations or they just hav't updated their wiki yet.
What I'm getting at is with a known distance the sun is when we see it at the horizon we could calculate the size it should appear due to shrinking effect and what what amount magnification it would need to bring it back to appear the same size we see it the rest of the time. Then maybe we could determine the source of magnification? Miising data= no accurate calculations.
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An illusion to the eye cannot produce a physical effect on an opposite horizon. That is the point I've been trying to convey to you. If the sun is not really at a low angle but only appears to be because it's an illusion, then it won't be able to do the things that it can only do if it is actually at a low angle.
Why not? That piece of sky high in altitude would be observing a red sunset. Why not see what the sky sees a further distance away, as if the sky were a mirror-like thing that reflects light?
The sky does reflect light...
The lower part of the sky would not be seeing the red sunset. The sun has set for that area of sky.
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On a flat earth, it can't be illusory because the physical phenomena is real. The light from the sun must somehow actually be grazing the earth at a low angle. That's why EAT makes more sense than "perspective" if the earth is flat.
As we've seen over and over again, the Sun has to be physically lower to produce the effects such as this, uplit clouds, rising shadow on Everest from a lower peak, etc. "Perspective", illusion, just doesn't cut it. EAT, upward bendy light, on the other hand, seems to be the only plausible explanation, which opens a whole other can of worms.
All you have to do is try it at home. Take a light source and point it an object that is lower than you target, simulating, let's say a 3000 mile high sun and 26000' lower object. Maintain the simulated sun height and keep moving backwards/away and see if you can get a shadow to climb up to the top of your 29000' target. The shadow will never get above "26000" feet no matter how far away you go. The only way to do so is to physically lower your light source. "Perspective" is not the answer.
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You assume that this would scale. Making your objects smaller does not cause the vanishing point to appear any nearer.
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On a flat earth, it can't be illusory because the physical phenomena is real. The light from the sun must somehow actually be grazing the earth at a low angle. That's why EAT makes more sense than "perspective" if the earth is flat.
As we've seen over and over again, the Sun has to be physically lower to produce the effects such as this, uplit clouds, rising shadow on Everest from a lower peak, etc.
If you think about what the objects you are looking at are seeing in those examples, all make sense.
Atmosphere, clouds, mountains, all reflect light to the observer.
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An illusion to the eye cannot produce a physical effect on an opposite horizon. That is the point I've been trying to convey to you. If the sun is not really at a low angle but only appears to be because it's an illusion, then it won't be able to do the things that it can only do if it is actually at a low angle.
Why not? That piece of sky high in altitude would be observing a red sunset. Why not see what the sky sees a further distance away, as if the sky were a mirror-like thing that reflects light?
The sky does reflect light...
You're reasoning in circles. Is the sun setting an illusion or not?
If the "piece of sky" is "observing a red sunset", why is it "observing a red sunset?" The illusory nature of Perspective can't make that possible. Clouds being lit up by sunlight isn't an illusion. They're really being lit up by the sun.
But how? Don't tell me "perspective" if you acknowledge that's illusory.
So you're left with the challenge of explaining how a sun can get to an actual low enough angle to light up things low in the sky without relying on the "it only appears to" perspective explanation.
The only way I can reason it is possible is that light from the sun would have to bend in the opposite direction of the way RET says the globe curves. That's why I give EAT any attention. You've mentioned EAT, but only in terms of what some others advocate. You don't (as far as I've seen). You've hung your model on ENaG perspective. But that is an inadequate explanation. Without even getting into Rowbotham's peculiar take on perspective, it's a perceptual solution that doesn't explain physical position of the sun that could cause the line of sight required to be responsible for the phenomena we're talking about.
You can't have it both ways. Either perspective is illusion and the sun is really at a higher angle (in which case it can't be illuminate the clouds or opposite horizon that way), or perspective has a physical effect and means parallel lines really do converge in planar geometry, which I'm not buying and I don't think you do either.
If you think about what the objects you are looking at are seeing in those examples, all make sense.
Atmosphere, clouds, mountains, all reflect light to the observer.
But how can they reflect light to the observer if the sun has "set?" How can the sun be "set" to an observer (camera) on a 2000' mountain top but still be visible to particles in the atmo-whatever further in the opposite direction away from the direction of setting? That's the mystery I don't see being solved unless you invoke bendy light. Perspective can't do that.
We can both agree it's happening. The question is how? I can fathom it on a globe earth because the earth's curvature is causing a shadow that you can get up out of with elevation, even if further away from the sun. I can fathom it on a flat earth if it's light that's curving, with the flat earth causing a shadow as the sun light passes over my head and illuminates things higher up and further away. But the perspective explanation on a flat earth doesn't work.
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On a flat earth, it can't be illusory because the physical phenomena is real. The light from the sun must somehow actually be grazing the earth at a low angle. That's why EAT makes more sense than "perspective" if the earth is flat.
As we've seen over and over again, the Sun has to be physically lower to produce the effects such as this, uplit clouds, rising shadow on Everest from a lower peak, etc.
If you think about what the objects you are looking at are seeing in those examples, all make sense.
Atmosphere, clouds, mountains, all reflect light to the observer.
Yes, I know you have this thing about the mountain, horizon or the cloud as the observer. But in reality, we are the observer. And like I stated, try it at home. If you can show what we observe as 'uplit' when the light source is 1000's of mile above the object/target, cool. But you can't. The light source has to be physically lower. "Perspective" is out. Focus on bendy light.
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On a flat earth, it can't be illusory because the physical phenomena is real. The light from the sun must somehow actually be grazing the earth at a low angle. That's why EAT makes more sense than "perspective" if the earth is flat.
As we've seen over and over again, the Sun has to be physically lower to produce the effects such as this, uplit clouds, rising shadow on Everest from a lower peak, etc.
If you think about what the objects you are looking at are seeing in those examples, all make sense.
Atmosphere, clouds, mountains, all reflect light to the observer.
Here again I refer you back to Bobby's OP that shows the shadowed San Diego county by the San Diego Mountains at sunrise. The west slope of the mountains and the entire landscape is in twilight all the way to the coast but the ocean at the horizon is illuminate by the sunlight. At some point the tops of the high rises at San Diego harbor will lite up while the rest of the landscape will be shadowed by the Laguna and Cuyamaca mountains until the sun rises over the top of those mountains. To the east of those mountains lies Imperial Valley and it's lite up entirely. This can only happen if the sun is below the elevation of the mountains at sunrise.
Down town San Diego is 55.3 miles from Laguna peak. Laguna peak is 6,382 feet in elevation. This phenomena can be seen on a clear day as well as with some clouds in the sky and/or poor air quality and conditions. Does not matter.
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The answer for the perspective explanation is that when you increase your altitude you are broadening your perspective lines, can see further, and it will take longer for the sun to set into your horizon. That part of the sky is seeing the sunset slightly higher, since that part of the sky is higher in altitude.
The explanation for EAT is that the sun's ray's are barely missing the earth and are hitting the red area of the horizon.
But on a flat earth with the sun always at 3.000 up from the surface of the earth, how does it get close to the horizon? Because there is no red areas unless the sun is near the horizon.
For that part of the sky the sun is near the horizon.
I am not sure what you are asking, exactly. The explanations would either be setting by perspective or EAT. For perspective the idea that the perspective lines would approach each other for infinity without meeting is disputed.
Disputed by who? You continue to misuse the word perspective.
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People always conflate optical perception with tangible perception. Lines may be tangibly parallel but not optically parallel if the lines are viewed from certain perspectives. When train tracks are viewed head on from the ground they are no longer optically parallel but at angles to each other while still being tangibly parallel. Tangible geometry does not change with perspective, optical geometry does. Read Bishop George Berkeley's works on optics for more on this.
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Another thing to keep in mind is that railroad tracks (in the US, at least) are only about 58 inches apart and take a mile or more to appear to converge. The sun is (depending on who you ask) anywhere from from a few hundred to a few thousand miles high but appears to converge with a horizon that is maybe a few dozen miles away. How does that make any logical sense whatsoever?
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Another thing to keep in mind is that railroad tracks (in the US, at least) are only about 58 inches apart and take a mile or more to appear to converge. The sun is (depending on who you ask) anywhere from from a few hundred to a few thousand miles high but appears to converge with a horizon that is maybe a few dozen miles away. How does that make any logical sense whatsoever?
I brought up that point in other threads but it got over looked or buried.
The missing part of the formula is the distance it would take the sun to converge with the horizon. Find that answer and it would tell us if it were possible by perspective or not. If that distance put the sun hundreds or thousands of miles out passed the edge of the flat earth then we know we need to look at alternative possibilities.
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Help me out here you guys with math skills
round off the 58" to 5'
1 mile to converge 5'.
The calculations I come up with is 3,168,000. if that's miles, the amount of miles it would take 3,000 to converge with the horizon, if that's correct the idea of perspective is screwed.
I could be way off though. But even it it were only 2 miles instead of 3 million miles off the edge of the flat earth it throws a wrench in the perspective idea.
Somebody else want to give it a try.
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You're using ratios, which works.
5:5280
3000:3168000
Using trig, a span of 5' at a distance of 5280' subtends an arc of 0.05426° or 3.25 arcminutes. That's probably not small enough to make the span appear to "merge," but let's just say it is for the sake of illustration.
For a span of 3000 miles to subtend an angle of 0.054°, it would have to be:
3000/tan(0.5426°) ~3,168,000 miles way.
Watch what happens. For 3000 to subtend the stated angle, it must be this far in the distance, per perspective:
1° -> 171,870 miles away
0.5° -> 343,766 miles away
0.25° -> 687,545 miles away
0.125° -> 1,375,100 miles away
0.063° -> 2,728,371 miles away
Every halving of the angular span requires a doubling of the distance. That's why a sun even just 10 miles above a flat earth runs out of real estate before it can drop to 1/60th of a degree elevation.
I mentioned that previously (https://forum.tfes.org/index.php?topic=11581.msg176753#msg176753), here and on the Unlit Clouds topic. For a sun to appear to set (or rise) on a flat earth, you've got to have some upward bending of the sun's light. Perspective doesn't cut it.
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You're using ratios, which works.
5:5280
3000:3168000
Using trig, a span of 5' at a distance of 5280' subtends an arc of 0.05426° or 3.25 arcminutes. That's probably not small enough to make the span appear to "merge," but let's just say it is for the sake of illustration.
For a span of 3000 miles to subtend an angle of 0.054°, it would have to be:
3000/tan(0.5426°) ~3,168,000 miles way.
Watch what happens. For 3000 to subtend the stated angle, it must be this far in the distance, per perspective:
1° -> 171,870 miles away
0.5° -> 343,766 miles away
0.25° -> 687,545 miles away
0.125° -> 1,375,100 miles away
0.063° -> 2,728,371 miles away
Every halving of the angular span requires a doubling of the distance. That's why a sun even just 10 miles above a flat earth runs out of real estate before it can drop to 1/60th of a degree elevation.
I mentioned that previously (https://forum.tfes.org/index.php?topic=11581.msg176753#msg176753), here and on the Unlit Clouds topic. For a sun to appear to set (or rise) on a flat earth, you've got to have some upward bending of the sun's light. Perspective doesn't cut it.
Then I guess you would have to factor in the speed of the sun. There's an estimate of around 4 minutes that it takes for the sun to meet the horizon to being below it. Obviously that varies. But given the distances above, the sun would have to be moving away at around 38,347,500 miles per hour, give or take.
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It's a phenomenon known as alpenglow. It's fairly common in mountain areas in the "blue hour" before sunrise or after sunset.
Alpenglow (from German: Alpenglühen, Italian: Enrosadira) is an optical phenomenon that appears as a horizontal reddish glow near the horizon opposite of the Sun when the solar disk is just below the horizon. This effect is easily visible when mountains are illuminated, but can also be seen when clouds are lit through backscatter.
Since the sun is below the horizon, there is no direct path for the sunlight to reach the mountain. Unlike sunrise or sunset, the light that causes alpenglow is reflected off airborne precipitation, ice crystals, or particulates in the lower atmosphere. These conditions differentiate between a normal sunrise or sunset, and alpenglow.
I was just told this phenomenon is the Belt of Venus (https://en.wikipedia.org/wiki/Belt_of_Venus). Sort of a variation on Alpenglow. Never heard of that before.
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Excellent image... looking west just before sunrise. So the dark grey band hugging the horizon is the shadow of the Earth disappearing westwards. The pinkish glow just above the dark band is known as the Belt of Venus. Lovely sight.