JohnAdams1145

Re: On a globe Earth the horizon should not curve
« Reply #60 on: April 15, 2018, 10:02:08 AM »
I suppose it's really hard to visualize this, but on a globe Earth the horizon should definitely curve, and the curve becomes more apparent the higher you go up. If you imagine the Earth as a basketball and hold it out in front of you, you can see that the basketball is clearly curved (duh!). But what are you really simulating here? An extremely high-altitude photograph of the sphere. To say that it wouldn't be curved at different altitudes is special pleading.

As for what this got derailed to: even if Parallax were right and a given river "dropped" in altitude by only x meters, it wouldn't support FE or RE, since we define "up" as the direction opposite the pull of gravity, and when you measure altitudes on a sphere, you'll notice that up is different for every point on its surface. The point is moot. But the other posters make a very good point in that the Nile cannot just drop one foot, because its source has been carefully verified to be much higher than that. Asserting that it isn't is delusional.

Morgenstund

Re: On a globe Earth the horizon should not curve
« Reply #61 on: April 15, 2018, 10:53:04 AM »
I suppose it's really hard to visualize this, but on a globe Earth the horizon should definitely curve, and the curve becomes more apparent the higher you go up. If you imagine the Earth as a basketball and hold it out in front of you, you can see that the basketball is clearly curved (duh!). But what are you really simulating here? An extremely high-altitude photograph of the sphere. To say that it wouldn't be curved at different altitudes is special pleading.

It is not difficult to visualize at all. I'm fully aware that when seen from above all the points on the horizon form a circle. But, as I have stated a few times now, that is not the kind of curvature the FEs claim we should observe if Earth were a sphere. They claim that the horizon, when observed at ground level should curve. I've seen videos where a random FE believer stands on the beach and points to the horizon saying 'See... it's a staight line. No curvature!!!' Of course there is no curvature. All the points on the horizon lie on the same plane level. It's like holding a hoola hoop horizontally and placing your head in the center. You don't see the curvature of the ring, you see a straight line.

And when you see images of Earth from space you see only a circular shape. It has become a 2D object. It could be a flat disk, it could be the end of a cylinder or a half-sphere for all we know. The circular shape does not necessarily indicate a sphere. If we had videos of the Earth rotating below us, now that would prove a globe Earth. Aren't we lucky:



I'm fully aware that the true believer in a Flat Earth will dismiss the video as photoshopped NASA/Illuminati/They (R) trickery, a part of the conspiracy, but the rest of us can enjoy it none the less.

« Last Edit: April 15, 2018, 11:50:50 AM by Morgenstund »

Morgenstund

Re: On a globe Earth the horizon should not curve
« Reply #62 on: April 15, 2018, 11:11:16 AM »
Rowbotham was called a doctor by his contemporaries and enemies and sources cite him as running a legitimate medical practice.
I have no problem with being corrected, and would be happy to take a look at those sources.

Refer to the conversation in this thread:

https://www.theflatearthsociety.org/forum/index.php?topic=61409.msg1607688#msg1607688

Quote from: Ski
I'm not sure why you are so disparaging about his title. As stated, even if he did not graduate from Edinburgh, it was not uncommon for people to study at university's without documentation, nor is it impossible that he graduated elsewhere before or after studying at Edinburgh, nor that that he was licensed through one of the many licensing bodies that existed at the time.

In addition, you are ignoring that not a single instance has been presented in contemporary accounts wherein he was called anything but doctor by anyone -- including his adversaries. To take the stance that he was not a doctor would also mean that you believed the Bookseller editor to be in on the conspiracy in 1885, naming him a doctor with a flourishing and legitimate practice, or that the AAAS in publishing one of the most respected scientific journals calls anyone and their brother doctor without regard for their actual career or qualifications.

IOW there are no historical records that can confirm that Rowbotham earned a legitimate doctor's titel from a genuine university or college. But even if he had obtained such a title it wouldn't give his conclusions any validity. 'Appeal to authority' is a logical fallacy, as we all know. The flaws in his arguments are obvious and the old Victorian show man did not prove a damned thing.

HorstFue

Re: On a globe Earth the horizon should not curve
« Reply #63 on: April 15, 2018, 02:25:41 PM »
Of course there is no curvature. All the points on the horizon lie on the same plane level. It's like holding a hoola hoop horizontally and placing your head in the center. You don't see the curvature of the ring, you see a straight line.

Sorry, again as stated earlier, the horizon curves, but so faint, that's impossible to see it without additional references.
Your example:
Placing the hoola hoop exactly at your eye level, so that the observer is exactly at center of the circle, yes, what you see is a straight line. If you lower the hoola hoop, you see part of an ellipse!
And yes, the horizon is a circle, mathematically what you get if you intersect a cone (or easier a plane) with a sphere.
On a sphere the observer cannot be at the center of the circle of the horizon, he would have to dig a hole, but then could not see anything. The center of the horizon circle is below the observer.

The normal field of view of human eyes is about 110° (about 120°, 2*60°, cos(60°)=0.5).
The dip angle in arc minutes (1°/60) of the central point is about 2.1*sqrt(h) (h=observers hight in meters).
The formula is for nautical miles, which makes it easy, as 1 nm = 1 arc minute.
Not changing your view, the sides at the limits of you field of view are about cos(60°)*h lower. So the additional dip angle is about half of the dip angle at the center.

some examples
h=2m, distance to horizon 3 nm, dip 3 arc minutes, additional dip 1.5 arc minutes, almost imperceptible.
h=10m, distance to horizon 6.6 nm, dip 6.6 arc minutes, additional dip 3.3 arc minutes, even with a reference line hard to see.
h=90m, distance to horizon 20nm, dip 20 arc minutes 0.33°, additional dip 0.16°, could be seen with a reference line.
Larger distances would blur the horizon, so it cannot be measured precisely any more, due to atmospheric diffraction.

So to do the experiment right, you would need.
Excellent viewing conditions (20nm)
clear view of the horizon over the complete field of your vision.
a slight sea, no waves
moderate hight of observer
reference line - Try to align a water spirit level with the horizon line.

The observable dip and so the curvature, measured as viewing angle is only fractions of one degree, and conditions to see it are rare.

Mr. Rowbotham did a similar experiment in EnaG http://www.sacred-texts.com/earth/za/za12.htm

but he didn't apply the necessary accuracy.
And overestimated the curve by far. The other figures he gives are ridiculous.

Morgenstund

Re: On a globe Earth the horizon should not curve
« Reply #64 on: April 15, 2018, 04:02:51 PM »
Of course there is no curvature. All the points on the horizon lie on the same plane level. It's like holding a hoola hoop horizontally and placing your head in the center. You don't see the curvature of the ring, you see a straight line.

Sorry, again as stated earlier, the horizon curves, but so faint, that's impossible to see it without additional references.
Your example:
Placing the hoola hoop exactly at your eye level, so that the observer is exactly at center of the circle, yes, what you see is a straight line. If you lower the hoola hoop, you see part of an ellipse!
And yes, the horizon is a circle, mathematically what you get if you intersect a cone (or easier a plane) with a sphere.
On a sphere the observer cannot be at the center of the circle of the horizon, he would have to dig a hole, but then could not see anything. The center of the horizon circle is below the observer.
Of course. We're observing the horizon from above the center. I haven't done the calculations but I'd quess not much more than 1 or 2 % of the radius above the plane. I regarded it negligible. Turns out it isn't:

The normal field of view of human eyes is about 110° (about 120°, 2*60°, cos(60°)=0.5).
The dip angle in arc minutes (1°/60) of the central point is about 2.1*sqrt(h) (h=observers hight in meters).
The formula is for nautical miles, which makes it easy, as 1 nm = 1 arc minute.
Not changing your view, the sides at the limits of you field of view are about cos(60°)*h lower. So the additional dip angle is about half of the dip angle at the center.

some examples
h=2m, distance to horizon 3 nm, dip 3 arc minutes, additional dip 1.5 arc minutes, almost imperceptible.
h=10m, distance to horizon 6.6 nm, dip 6.6 arc minutes, additional dip 3.3 arc minutes, even with a reference line hard to see.
h=90m, distance to horizon 20nm, dip 20 arc minutes 0.33°, additional dip 0.16°, could be seen with a reference line.
Larger distances would blur the horizon, so it cannot be measured precisely any more, due to atmospheric diffraction.

So to do the experiment right, you would need.
Excellent viewing conditions (20nm)
clear view of the horizon over the complete field of your vision.
a slight sea, no waves
moderate hight of observer
reference line - Try to align a water spirit level with the horizon line.

The observable dip and so the curvature, measured as viewing angle is only fractions of one degree, and conditions to see it are rare.

Mr. Rowbotham did a similar experiment in EnaG http://www.sacred-texts.com/earth/za/za12.htm

but he didn't apply the necessary accuracy.
And overestimated the curve by far. The other figures he gives are ridiculous.

Good Sir, I see that you have spent far more time studying these matters than I have. I appreciate your explanations. I'm still not convinced, though, that the curvature we both agree should be observed under optimal conditions, is the curvature FEs say is absent and thus proof of a flat Earth. Could you at least give me that one ;)

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Offline Stagiri

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Re: On a globe Earth the horizon should not curve
« Reply #65 on: April 15, 2018, 04:34:33 PM »
On a sphere the observer cannot be at the center of the circle of the horizon, he would have to dig a hole, but then could not see anything.

For whatever reason, I immediately pictured that situation in my mind and it made me laugh. Thank you, good sir, for making my day  :)
Dr Rowbotham was accurate in his experiments.
How do you know without repeating them?
Because they don't need to be repeated, they were correct.

HorstFue

Re: On a globe Earth the horizon should not curve
« Reply #66 on: April 15, 2018, 05:41:35 PM »
Of course. We're observing the horizon from above the center. I haven't done the calculations but I'd quess not much more than 1 or 2 % of the radius above the plane. I regarded it negligible. Turns out it isn't:

1 or 2%? 1% would be at observers hight about 1000m and distance of horizon 66nm = 122854m

Good Sir, I see that you have spent far more time studying these matters than I have. I appreciate your explanations. I'm still not convinced, though, that the curvature we both agree should be observed under optimal conditions, is the curvature FEs say is absent and thus proof of a flat Earth. Could you at least give me that one ;)
Yes, the curve is so faint, that a casual observer will never notice it. Even at an adequate hight, you could not be sure if lens distortions - camera or eye! - will be the cause of this.
And getting even higher does not make it better, as then the horizon is blurred by atmospheric diffraction.
You explicitly have to do the proposed experiment, with high accuracy.

Morgenstund

Re: On a globe Earth the horizon should not curve
« Reply #67 on: April 15, 2018, 06:23:06 PM »
Of course. We're observing the horizon from above the center. I haven't done the calculations but I'd quess not much more than 1 or 2 % of the radius above the plane. I regarded it negligible. Turns out it isn't:

1 or 2%? 1% would be at observers hight about 1000m and distance of horizon 66nm = 122854m
Hmm... I used the '8' per mile sqr' and really messed up the conversion to metric (and probably used 8 ft instead of 8 inches).
Instead I've found an 'Earth curvature calculator'
http://earthcurvature.com/
and with a radius of 5 km the 'drop' is calculated to be 1.96 m. Add another 3 m which puts the observer 5 m above the horizon. That's 0,1% of the radius. I was off by a factor of 10 (I was out dancing last night!).

Good Sir, I see that you have spent far more time studying these matters than I have. I appreciate your explanations. I'm still not convinced, though, that the curvature we both agree should be observed under optimal conditions, is the curvature FEs say is absent and thus proof of a flat Earth. Could you at least give me that one ;)
Yes, the curve is so faint, that a casual observer will never notice it. Even at an adequate hight, you could not be sure if lens distortions - camera or eye! - will be the cause of this.
And getting even higher does not make it better, as then the horizon is blurred by atmospheric diffraction.
You explicitly have to do the proposed experiment, with high accuracy.
You mention the blurred horizon caused by atmospheric diffraction. Do you agree that on a flat Earth there would be no crisp and clear horizon as the one we can actually observe?

HorstFue

Re: On a globe Earth the horizon should not curve
« Reply #68 on: April 15, 2018, 09:57:44 PM »
You mention the blurred horizon caused by atmospheric diffraction. Do you agree that on a flat Earth there would be no crisp and clear horizon as the one we can actually observe?
For me the crisp and clear horizon out at sea is a clear evidence for the curvature on a sphere. I guess on a flat earth there would be no such crisp line. I didn't make a claim from it, as I found no bullet proof evidence, lacking an example ;)
some hints
e.g. out at sea sometimes you cannot find the horizon line, due to haze, when too much vapor in the air don't let you see so far, or atmospheric refraction will blur the scene with mirage effects or similar.
e.g. FE themselves claim with the "law of perspective", that horizon is there, where eye resolution "ends". So what else than a blur would result. Btw. I still cannot understand, why with "law of perspective" the distance to the horizon depends on observers hight. Ok for all objects smaller than observers hight, but what for objects larger than observers hight, or high contrast objects, like the bright light of a lighthouse or even better the stars at night. Now where's the horizon?

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Offline Tom Bishop

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Re: On a globe Earth the horizon should not curve
« Reply #69 on: April 15, 2018, 11:30:40 PM »
Read Earth Not a Globe on how perspective limits the distance seen.

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Offline nickrulercreator

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Re: On a globe Earth the horizon should not curve
« Reply #70 on: April 16, 2018, 12:04:21 AM »
Read Earth Not a Globe on how perspective limits the distance seen.

No, ENAG is wrong about perspective. If it was correct, I should be able to zoom back in on objects like the sun, or buildings, or even some boats that are far enough out, and "restore" them from being hidden by "perspective." But I can't.

It also doesn't explain why objects disappear bottom up. If it was because of "perspective," should the objects not entirely disappear at the same time?
This end should point toward the ground if you want to go to space. If it starts pointing toward space you are having a bad problem and you will not go to space today.

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Offline xenotolerance

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Re: On a globe Earth the horizon should not curve
« Reply #71 on: April 16, 2018, 02:35:42 AM »
Specifically, Rowbotham explicitly predicts that everything should disappear by its smallest regions first.

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Offline Tom Bishop

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Re: On a globe Earth the horizon should not curve
« Reply #72 on: April 16, 2018, 04:10:23 AM »
Read Earth Not a Globe on how perspective limits the distance seen.

No, ENAG is wrong about perspective. If it was correct, I should be able to zoom back in on objects like the sun, or buildings, or even some boats that are far enough out, and "restore" them from being hidden by "perspective." But I can't.

It also doesn't explain why objects disappear bottom up. If it was because of "perspective," should the objects not entirely disappear at the same time?

The explanation predicts that waves and other imperfections on earth will intersect the true horizon at eye level, hence why the sun cannot be restored.

Re: On a globe Earth the horizon should not curve
« Reply #73 on: April 16, 2018, 07:41:37 AM »
Read Earth Not a Globe on how perspective limits the distance seen.

No, ENAG is wrong about perspective. If it was correct, I should be able to zoom back in on objects like the sun, or buildings, or even some boats that are far enough out, and "restore" them from being hidden by "perspective." But I can't.

It also doesn't explain why objects disappear bottom up. If it was because of "perspective," should the objects not entirely disappear at the same time?

The explanation predicts that waves and other imperfections on earth will intersect the true horizon at eye level, hence why the sun cannot be restored.

😂

Are you able to cite any sources that aren't written by a fake doctor with no qualifications in an era when they thought it was a good idea to put heroin in cough medicine?

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Offline Tom Bishop

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Re: On a globe Earth the horizon should not curve
« Reply #74 on: April 16, 2018, 08:00:23 AM »
Read Earth Not a Globe on how perspective limits the distance seen.

No, ENAG is wrong about perspective. If it was correct, I should be able to zoom back in on objects like the sun, or buildings, or even some boats that are far enough out, and "restore" them from being hidden by "perspective." But I can't.

It also doesn't explain why objects disappear bottom up. If it was because of "perspective," should the objects not entirely disappear at the same time?

The explanation predicts that waves and other imperfections on earth will intersect the true horizon at eye level, hence why the sun cannot be restored.

😂

Are you able to cite any sources that aren't written by a fake doctor with no qualifications in an era when they thought it was a good idea to put heroin in cough medicine?

Rowbotham was a doctor. Please stop disparaging his name. Earth Not a Globe was peer reviewed by a journal called The Earth Not a Globe Review. You can look into that.

Also, heroin in cough medicine did work and was studied to be safe. Do you think that the medical system of the 1800's didn't study the safety of drugs before giving them to people?

Most of the "lol, doctors used to do this" crap is based on personal ignorance.

The opium poppy, from which Herioin is extracted, has been cultivated for more than five thousand years for a variety of medicinal uses. Heroin is still  today for legal medical purposes. Doctors often prefer to give patients heroin over morphine because it is fat soluble.

Just because some people abused Heroin and it was decided to stop making it easily accessible to the public over the counter, it doesn't mean that it doesn't have a legitimate medical purpose. You can take your dumb anecdotes and personal ignorance elsewhere.
« Last Edit: April 16, 2018, 08:03:41 AM by Tom Bishop »

Re: On a globe Earth the horizon should not curve
« Reply #75 on: April 16, 2018, 08:12:44 AM »
Read Earth Not a Globe on how perspective limits the distance seen.

No, ENAG is wrong about perspective. If it was correct, I should be able to zoom back in on objects like the sun, or buildings, or even some boats that are far enough out, and "restore" them from being hidden by "perspective." But I can't.

It also doesn't explain why objects disappear bottom up. If it was because of "perspective," should the objects not entirely disappear at the same time?

The explanation predicts that waves and other imperfections on earth will intersect the true horizon at eye level, hence why the sun cannot be restored.

😂

Are you able to cite any sources that aren't written by a fake doctor with no qualifications in an era when they thought it was a good idea to put heroin in cough medicine?

Rowbotham was a doctor. Please stop disparaging his name. Earth Not a Globe was peer reviewed by a journal called The Earth Not a Globe Review. You can look into that.

Also, heroin in cough medicine did work and was studied to be safe. Do you think that the medical system of the 1800's didn't study the safety of drugs before giving them to people?

Most of the "lol, doctors used to do this" crap is based on personal ignorance.

The opium poppy, from which Herioin is extracted, has been cultivated for more than five thousand years for a variety of medicinal uses. Heroin is still  today for legal medical purposes. Doctors often prefer to give patients heroin over morphine because it is fat soluble.

Just because some people abused Heroin and it was decided to stop making it easily accessible to the public over the counter, it doesn't mean that it doesn't have a legitimate medical purpose.

No Tom, heroin is a highly addictive substance that should never have been handed out to people for the treatment of coughs and colds.

It was created and distributed under the mistaken notion that it was less addictive than morphine.

And Rowbotham was not a doctor and made stuff up under the pretense of science and so deserves to be disparaged.

Re: On a globe Earth the horizon should not curve
« Reply #76 on: April 16, 2018, 08:21:04 AM »
Read Earth Not a Globe on how perspective limits the distance seen.

No, ENAG is wrong about perspective. If it was correct, I should be able to zoom back in on objects like the sun, or buildings, or even some boats that are far enough out, and "restore" them from being hidden by "perspective." But I can't.

It also doesn't explain why objects disappear bottom up. If it was because of "perspective," should the objects not entirely disappear at the same time?

The explanation predicts that waves and other imperfections on earth will intersect the true horizon at eye level, hence why the sun cannot be restored.
And I have shown in this thread - which you cleverly deflected into a debate about whether the horizon was at eye level - that the explanation of waves is horseshit

https://forum.tfes.org/index.php?topic=9338.msg145931#msg145931

If your eye height is above wave height then the waves cannot obscure the sun, so sunset would not occur if you're at any altitude.
It does.
If you are making your claim without evidence then we can discard it without evidence.

Re: On a globe Earth the horizon should not curve
« Reply #77 on: April 16, 2018, 08:25:05 AM »
Rowbotham was a doctor.
Cool. So next time I want to learn more about physics or astronomy I'll talk to my local doctor next time I have an appointment. None of this "trained scientist" nonsense, what do they know?

Quote
Earth Not a Globe was peer reviewed by a journal called The Earth Not a Globe Review. You can look into that.
They sound like independent experts.
In unrelated news I had my "There are Faeries at the Bottom of my Garden" thesis peer reviewed by the "Faeries are Real" society. They agreed I was right.
If you are making your claim without evidence then we can discard it without evidence.

Re: On a globe Earth the horizon should not curve
« Reply #78 on: April 16, 2018, 10:17:19 AM »
Read Earth Not a Globe on how perspective limits the distance seen.

No, ENAG is wrong about perspective. If it was correct, I should be able to zoom back in on objects like the sun, or buildings, or even some boats that are far enough out, and "restore" them from being hidden by "perspective." But I can't.

It also doesn't explain why objects disappear bottom up. If it was because of "perspective," should the objects not entirely disappear at the same time?

The explanation predicts that waves and other imperfections on earth will intersect the true horizon at eye level, hence why the sun cannot be restored.

😂

Are you able to cite any sources that aren't written by a fake doctor with no qualifications in an era when they thought it was a good idea to put heroin in cough medicine?

Rowbotham was a doctor. Please stop disparaging his name. Earth Not a Globe was peer reviewed by a journal called The Earth Not a Globe Review. You can look into that.

Also, heroin in cough medicine did work and was studied to be safe. Do you think that the medical system of the 1800's didn't study the safety of drugs before giving them to people?

Most of the "lol, doctors used to do this" crap is based on personal ignorance.

The opium poppy, from which Herioin is extracted, has been cultivated for more than five thousand years for a variety of medicinal uses. Heroin is still  today for legal medical purposes. Doctors often prefer to give patients heroin over morphine because it is fat soluble.

Just because some people abused Heroin and it was decided to stop making it easily accessible to the public over the counter, it doesn't mean that it doesn't have a legitimate medical purpose. You can take your dumb anecdotes and personal ignorance elsewhere.

Anyway, to sum up, no, you can't name any other sources for this idea you have picked up as to how perspective works.

So Rowbotham is the only source for this? No one else has indipendantly arrived at this idea, but have just taken Rowbothams word for it?

I think at best using this info in debates holds as much water as stating 'it's true 'cause my mate said so'...

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Offline junker

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Re: On a globe Earth the horizon should not curve
« Reply #79 on: April 16, 2018, 05:14:41 PM »
Farty McFartwhistle was considered by both his followers and detractors alike as being the fartiest of all whistles.



See, anyone can just type stuff...

Refrain from low-content posting in the upper fora. Warned.

Also, this is your 3rd warning within a month or so. Next one is a 3-day ban to review the rules.