Eratosthenes's method of using sticks in the ground to make sundials. If the earth was flat then you wouldn't see these shifts. Not only was he able to prove the earth was round, he calculated its curvature--and did a really good job too.

Image version

This. Flat earth requires one to ignore a bunch of settled science. Centuries of it. It also seems like a pointless distraction when there's other business to be done.

cmon thats not really a great argument seeing as the moon landing was used to "prove gravity" with the hammer/feather drop.

and pssh the moon landing is definitely not "settled science". that shit was a fake. this doesnt mean the earth cant be a sphere though..

plus think about how every now and again we have a scientific discovery practically overwrite someones life work..

im not promoting flat earth or ball earth for that matter, it just bothers me to see so many people shit on valid questions on every place its brought up. that alone would make me question anything if i were just an unbiased spectator.

I'm all for spirited debate - even if it's over something inane and purely entertaining like whether Star Trek or Star Wars is more realistic. Earth shape debate falls into that category for me. Comparing, say, the evolution of disease treatment from bloodletting to gene editing and recognizing the man-centuries of effort that happened between those two understandings vs. something like the moon landings, which were a small number of events controlled by one group or nation.

It seems to me that flat earth belongs more in r/fringetheory.

it was just a small analogy and i was sorta trying to downplay it at first due to its short span of time.

i can see where youre coming from.. but being in this sub long enough, i dont doubt TPTB ability to pull a long con. tell a lie so well people cant help but laugh at the truth.. theres an odd quote about that btw.. i dont see it any dif then people using certain mathematical and "scientific" based proofs to talk about anything space related.

i cant accept ball earth until i see a shot of it from space that is a non cgi, non edited, no fish eye, rather raw camera. forget the math. show me a real photo/video. and i mean REAL

i cant accept flat earth until i see something similar...

at this point in time earth may as well be shaped like a kidney bean to me.

Sure, I totally get where you're coming from. I'm skeptical by nature and there are definitely things about certain accepted science and events that give me pause. The NIH claims their explanation for the collapses on 911 are "scientific". Riiiiiight. Nature really prefers three dimensional objects to be round though. So it seems like a disconnect from a bunch of preceding and related science to except the earth from that inclination. Don't we have shuttle and other rocket footage of the curve emerging once significant distance is achieved? Curious. I'm gonna have to check out the disagreement you mentioned. Thanks!

yea were on the same page on 9/11, i had a hunch i wouldnt even have to mention that with ya. Glad i didnt lol.

youre right, tests agree with you and many other people. Sadly, video/pictorial evidence shows something contrary to what we should expect based on the "math" and "proof" weve accepted. You can do some math yourself like ive done.. lookup high altitude shots with verifiable altitudes/flight times. You should be able to calculate, using the math given to us, how much of the earths surface u can see based on distance to horizon and if you think you should see curve. You could also shortcut that and punch in a flat model and spherical model into a pc program to do it for you. Curve, ime, becomes heavily evident around 30-40mi, the math tends to agree, yet what we see on earth doesnt.. Shit felix from the redbull statos dive should have landed in the ocean off the west coast based on flight time but he barely moved when you consider the earth spun beneath him for hours. The winds must have been over 1000mph! Or something else.. And dont get me wrong, i looked at these thigs attempting to prove to myself the earth can only be round, and im failing thus far.

lol you can find Neil Degrasse tyson, the sad face of science today, disagrees with himself... before even moving onto others. I used to look up to neil as a kid, seein him at the planetarium, before lookong into the moon landing and more as a teen. Now im literally going back to gradeschool shit to see if my teachers innocently ignorantly lied to me in gradeschool

im sorry btw, id provide links, but i honestly get tired of linking shit sometimes. You can find everything i say on the good ol' internet yourself. I prefer people to go about it themselves anyway. Its a healthier learning process imo and what you get out of it weighs more heavily on you than if i just linked everything im saying.

oh and Im glad weve kept this civil.. idk if it was OP's words or how you are but idt ive ever got this far into a chat about this without it digressing.. and were barely a few responses in. Fun talk!

I really appreciate that. I have limited time to spend online and I really value constructive interaction. Narrative reinforcing echo chambers are not my thing. Likewise, I enjoyed our dialog and hope to continue it soon on this or another topic. I feel like people are capable of doing their own research so I don't always link either. It's not really about the linked content every time anyway. I was doing business in NYC from the 8-10 of September 2001, and my flight was mechanically laid over so I saw the second plane hit on live teevee. I and the other people in the gate waiting were like "they dropped those buildings - this is bullshit" and then when they announced WTC 7 had fallen while we're watching it standing there in the background of the newscast. No one could fucking believe it. Then we watched it free fall live 20 minutes later. Then the tiny hole in the Pentagon and the not plane crash in PA. So 911 is a big deal for me and a lot of the details I recall came in real or near real time.

I was paying attention before but I was super duper wide awake after that. 16 years of rabbit holes and digging later...

The winds must have been around 1000mph!

Funnily enough, they basically were.

If you were in orbit above the earth looking down, you'd see the earth rotating underneath you at a little over 1,000 miles per hour. You'd also see the clouds rotating with the earth at a little over 1,000 per hour.

From the ground they could appear to be completely motionless, but only because you're rotating at the same speed they are.

That's why Baumgartner did not land in the ocean... he was rotating with the atmosphere at essentially the same speed the earth itself was rotating. From the ground it appeared he didn't go very far at all, but from that fixed point in space, you'd see he actually traveled thousands of miles.

yea because the atmosphere is moving with him..

oh hurr durr coriolis effect

lol you addressed one point and speak with utter confidence. what about the other reasons?

before this digresses into the next step, i wont be responding.... toodaloo...

yea because the atmosphere is moving with him..

Yes. You may be stumped by such simple explanations, but that doesn't change the fact that they are true.

oh hurr durr coriolis effect

That has nothing to do with it.

This force causes moving objects on the surface of the Earth to be deflected to the right (with respect to the direction of travel) in the Northern Hemisphere and to the left in the Southern Hemisphere.

https://en.wikipedia.org/wiki/Coriolis_force

The atmosphere rotates with the earth due to gravity and friction.

what about the other reasons?

What other reasons? Do you mean this:

Curve, ime with models, becomes heavily evident around 30-40mi, the math tends to agree, yet what we see on earth doesnt.

That's not a reason, that's pure bullshit. For example, Baumgartner jumped from an altitude of 21 miles, not 30 or 40. No commercial airliner ever gets anywhere near 10 miles high. All those balloon videos you see also stay well below 30 miles, which is 158,400 feet.

The current world record for a balloon, launched by the Japanese version of NASA reached an altitude of 32 miles.

So for your answer as to why we don't see images from that sort of altitude that show the curvature, the truth is we do, but they come from the kinds of sources the flat earth morons refuse to believe, like NASA.

Was that what you wanted to hear? I doubt it, because it is the truth and it shoots down your arguments completely.

And at that height curve should be heavily evident.. did i mention commercial airliners? Did i say its not evident at 16/17mi? ommission doesnt correlate anything. you have terrible arguments be it about flat earth or any subject. why do you poke and prod? instigative.. triggered.. ugh. and idk why im botherig. call it boredom.. but this time i truly dont care what aggravated shit u type, i aint botherin in this thread. just wanted to make sure im clear.

Lol you can choose to believe nasa, only helps me and others see the tomfoolery..

You shot down what? https://youtu.be/CzyPN8-AbJQ

toodaloo motha fucka

ommission doesnt correlate anything.

That's my point. You asked me to address your "other reasons", and the claim that the curvature should be visible from 30 to 40 miles was the only one I could find.

Now you're telling me I should address the reasons you omitted?

If you ask why the curvature is not visible from a commercial airliner, the answer is, it is.

A curved horizon - no fisheye

You shot down what?

I shot down the flat earth bullshit. Easily.

lol

You can clearly see that there is no distortion of the wing at the edges of the frame.

This is the problem with flat earthers. They simply refuse to see the evidence of curvature while claiming there is none.

im more curious whats going on in your head. i know many psychs i can reference.

I'm sure you do. Hopefully one day they will help you.

theyre called connections, way to do the opposite of op's request since you got in here. triggerrreddd. ive resorted to sarcasm because im entertained.. go on...

theyre called connections, friends' references.. guess thats hard for an aggregator to understand or resist capitalizing on strawman arguments.

Huh> You're the one that brought your "connections" into the discussion. And by "resist capitalizing on strawman arguments", are you suggesting that your argument was a strawman?

btw.. way to do the opposite of op's request since you got in here. triggerrreddd. from thought provoking conversation to childish antics.

Huh? You're the one that resorted to ad hominem arguments by suggesting that there is something different about my psychology.

ive resorted to sarcasm because im entertained..

And you even admit you're the one the resorted to childish antics.

and when im entertained, ill go back on things i say.

What, so you just make shit up as you go alone, and then simply "go back on" it when called out?

fyi, i aint no flat earther.

It doesn't take a belief in flat earth to be a moron, as you've proved.

#Sigh

Yawn.

thats not really a great argument seeing as the moon landing was used to "prove gravity" with the hammer/feather drop.

No, it wasn't used to "prove gravity". It was a gimmicky demonstration of certain aspects of the theory that were proved long before.

it just bothers me to see so many people shit on valid questions on every place its brought up.

The problem is, they do not bring up "valid questions", they assert utterly invalid statements that have been disproved time and again.

"Why does the earth appear to be flat?" is a valid question. "The earth is obviously flat because it looks flat!" is an invalid statement.

That's the difference.

so to question not seeing curve at 90 miles up is not a valid question?? mmmk than?

i guess the way earth looks behind the moon to the dscovr satellite is also accurate.. https://www.nasa.gov/sites/default/files/thumbnails/image/epicearthmoonstill.png

k this time, im out

So, take measurements at many different points. Europe and Africa would be the best place to conduct this experiment. A north-south line running from Finland through South Africa offers the most land over which to conduct the experiment.

Get a bunch of people at different latitudes along that line to do the Eratosthenes experiment on the same day at the same time. It might take a lot of organization, but with the internet, it's entirely within the grasp of anyone with email.

Not sure how to take the tilt of the earth into account for that. Did Erastothenes?

Excellent question.

The shadow of a stick in January will differ from the shadow of the same stick in June. Sticks in different locations will also cast different shadows. We don't want these two different things to screw up the experiment. Since different times of the year cause an effect we want to avoid, all measurements would need to be taken at the same time.

Eratosthenes accounted for this by making his measurement on the Summer Solstice. His first "measurement" was of zero degrees in the city of Syene. It was well known and widely observed that vertical objects cast no shadows, and you could see to the bottom of wells on the Summer Solstice. His second measurement was in Alexandria at noon on the same day.

Taking measurements on the solstice was sort of necessary for Eratosthenes, because he was doing this by himself, and didn't have access to things like the internet. For us, as long as all measurements are taken on the same day at noon, the tilt of Earth shouldn't matter.

Well he didn't get it 100%, just very close to the actual value

Why would you choose a relatively rare phenomenon where the sun's rays reflect off the clouds to give the impression it's nearby rather than just clear skies?

Here's how they've calculated the distance to the sun before

Is there a way to find out how far away the sun is? And those pictures of the sun where the rays/light is coming out of the clouds at different angles, wouldn't that give the same effect of shadows being cast at different angles?

The sun rays are actually straight, they appear to be at angles due to perspective, much like train tracks coming closer together in the distance.

Here is what they actually look like:

http://blogs.discovermagazine.com/badastronomy/2011/11/02/crepuscular-rays-are-parallel/

Although I did mention no NASA.

Why? Here is the thing... you are essentially saying you'll refuse to consider evidence because that evidence could be fake... despite having no proof that NASA is faking anything.

You seem more willing to believe some YouTube video by someone who has no clue what they are talking about.

Why do you not treat them with the same level of scepticism?

In my mind NASA is a proven liar.

And there is your problem. You've swallowed the bullshit claims in YouTube videos without a trace of scepticism.

There's plenty of evidence for that.

No, there isn't. There are plenty of bullshit claims made by ignorant people, but that isn't evidence.

There's plenty of evidence for that. I can choose to discredit their explanations and research and look for other evidence.

Well, I've posted a very simple proof that the earth is not flat in this comment.

You don't even have to do the maths yourself. The calculator I used is not associated with NASA, but if you do not trust it, you can work out the maths yourself.

If you choose to not believe this simple proof, it proves you are not seeking the truth, but are instead seeking validation of your incorrect beliefs.

You don't seem to understand the point of the examples given ...

I think it's probably because they didn't see the need to have somebody on the ground photographing such a typical phenomenon?

The same thing happens with trees, you'd never say the sun is 'right behind the trees' in these examples:

https://www.google.cz/search?q=trees+crepuscular&source=lnms&tbm=isch&sa=X&ved=0ahUKEwi06cWhu4DUAhVHXBQKHTmSAmwQ_AUICigB&biw=1579&bih=868

TL;DR: if you use flat earth assumptions,Eratosthenes's experiment could work if the sun was 6982 km in the sky. However, doing so ends up proving that the earth can’t be flat anyway.

Sun rays are all basically parallel, the pictures you see where they appear to converge are no different than train tracks converging. However, let's pretend light does come down at different angles and the earth is flat, and calculate how high the sun would be with Eratosthenes's experiment.

In the original experiment, Eratosthenes measured the distance between two cities, Syene and Alexandria. He measured it at 5000 stadia. There's some debate about how far a stadia is exactly (bronze age civilizations weren't big on standardization), but I'll use 176.4 meters, since that seems to be the generally accepted value. That means they're about 882 kilometers apart. He also measured the different angles. He got 1/50th of a circle (about 7.2 degrees) off from vertical (or 82.8 degrees up from the horizon).

Now, we can imagine a right triangle. Because the sun was directly overhead at Syene, we can place our right angle there. We can then draw a across to Alexandria, another up to the sun, and the third line straight back down to Syene. If you’re good at trigonometry, you can break out a paper and pencil to figure out the sizes of that triangle to get the height of the sun. If you’re lazy (like me), you’ll use a calculator like this one. We can set angle alpha as 82.8 degrees (the measurement at Alexandria) and side b as 882 kilometers, and we’ll solve for side a to get the height to the sun. I got 6982 Km to the sun.

The next fun step is to start trying to figure out how far away the sun would have to be to appear to set (that trig calculator makes it easy). Even getting it within 5 degrees of the horizon is an enlightening proof as to why the earth can’t be flat.

Yeah, if the sun were that high, it would never appear to set below the horizon, because it’d have to move several times the diameter of the flat earth to even get close to the horizon. We know it can’t be, because we can measure the spot it’s directly over (lots of people live in the tropics).

As to the atmosphere acting as a lens; I’ve seen the same video, and he doesn’t have a leg to stand on. Let’s forget that he has zero experimental evidence for a moment. We can measure how much the atmosphere should bend light. The effect is small. Way too small for it to have the effects he describes. Let’s take a city in the American South West. I live almost a mile up, so I only have 80% the atmosphere that sea level has. However, when you plot the times for my sunset, it’s as if this distance in atmosphere had a negligible effect. My times are consistent with my longitude, exactly as you’d expect on a sphere.

Additionally, thunderstorms are very common where I live. Pressure and humidity can change wildly within the span of half an hour as a storm sweeps across the horizon. These storms are very common during sunset but, despite the havoc they’re causing to the surrounding air, there isn’t the slightest change in the position of the sun nor the time of sunset. If the atmosphere had a strong effect on light, shouldn’t these storms act like funhouse mirrors for the sun, even if only slightly?

It’s a great hypothesis, but there’s just no data to back it up.

The point is, it would never get even close to the horizon. We know how far different parts of the world are from each other. If the sun were only a few thousand miles up, it would never get within 15-20 degrees of the horizon for most of the people on the planet (for reference, your fist held at arms length, is about 10 degrees). Even if we give a very generous 5 degree margin of error for atmospheric effects (I'd be surprised if it was more than 1 or 2 degrees, about the width of your pinky finger at arms length), we'd still never see the sun get close. It would, at best, fade from our site while still well above the horizon.

In my mind, this is clear evidence that a flat earth isn't even remotely possible, there is no way to reconcile the chaotic atmosphere we measure and see every day with the idea that light is being horribly distorted and bent in such a predictable and regular manner. We can predict the exact time to sunset months and years out with accuracy, yet it's almost impossible to get a simple 7 day forecast right.

I have yet to see any flat earth model that is both internally consistent and makes sense with the world I observe around me. If someone could propose such a model, I'd quickly begin seriously questioning my views of the universe. As it stands, the standard model that is generally accepted is simply too good at allowing me to make predictions about the world around me.

Doubling your speed in a car quadruples the stopping distance, thrown objects follow parabolas, buoyancy and dense things sinking only makes sense if you assume gravity, water doesn't "find a level" but reacts to the forces acting on it. These and other lessons are powerful tools that let me make informed and accurate decisions in my daily life. As soon as a flat earth model can come close to matching that predictive power, then I'll be happy to get on board.

Non-Mobile link: https://en.wikipedia.org/wiki/Horizon

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Keep in mind that this is using the standard spherical earth model. It's numbers will have no bearing on a flat earth. It is also for calculating the distance to something on the ground, so you'll have to really change up the equations to calibrate for something thousands of miles in the air. 7000 km up is only 7000 km away when it's exactly over head.

You'll need to look at how the equation was formed, and understand the math used to derive it in the first place. A lot of what you're seeing on the page comes from a radius of a sphere (the earth's radius in this case), as well as the trigonometry of calculating tangent lines on that sphere. This entire approach makes no sense on a flat earth.

This is what I mean when I say no flat earth model describes what we see in real life. The fundamental equations we use to navigate and determine our height from sea level that work so well simply break down if you assume a flat earth. Things that we know work only work because they assume the earth is round.

Furthermore, the paragraph you posted about distance to the horizon is if you're at that height. It has nothing to do with objects in the sky, or their visibility. I'd recommend looking up a tutorial for trigonometry (and pre-calculus level algebra) to gain a better insight into what these equations are actually describing. Without that understanding, you'll be at a real disadvantage when trying to predict what we should and shouldn't be able to see in the world around us, as well as how to spot when someone else makes an error in their calculations.

You can simply plug and play with these equations, but you have to be VERY careful to pay attention to exactly how they are intended to be used. If you are within their bounds, then you'll be fine. However, if you want some flexibility, if you want to be able to move beyond the bounds by altering the equations to more accurately suit your particular needs for your exact situation, then you absolutely need an understanding of how the equation was constructed.

How close to sea level is "near sea level"? What kind of errors are you introducing when you go above that point? Do you even care about where the error manifests?

It's not impossible to be able to utilize these tools, but you will be at a significant disadvantage if you don't have a firm grasp of what these equations are actually saying, and what assumptions are implicit in their derivation.

Actually, the first equation very much takes the earth's radius into account. Here you can see where that equation came from. That last step is the simplified version, but it is based on a sphere, where the radius is a lot bigger than the height of the observer. It approximates some things, because the discrepancies are small when you're only a few miles up and it makes the math easier. However, when you start trying to use that equation for heights in the thousands of miles, those approximations start becoming major errors.

In the picture, every time you see an "R" it's talking about the radius. Ever time you see a "~" it's an approximation. This equation assumes that the earth is a perfect sphere, even if the last step obscures that. Trying to use it with flat earth assumptions makes all the answers meaningless, because of where the numbers you're using came from.

Again, I must stress that you should look into getting a more formal understanding of trigonometry. Even a relatively low level understanding will equip you well beyond what most people who make flat earth videos on youtube are capable of. You'll be able to derive these equations yourself, from scratch. In fact, on a flat earth, computing these kinds of equations is much simpler!

There is some apparent convergence, just like with railroad tracks. But, remember the trigonometry. You are standing about 6-ish feet off the ground. You can use that handy dandy right triangle calculator I posted earlier and try to model the apparent angle from your eye to the ground, and then from your eye to the sun. the apparent angle between them gets smaller, but we're talking tens of thousands of miles distant (whole circumference of the earth is a little less than 25000 miles) before they get within 5 degrees of each other. Again, there will be some distortion from the atmosphere, but no where near enough to accommodate the angles we'd expect.

Here is a screenshot of that video

The first thing to notice is that the sun is still perfectly visible as it sets. It has not shrunk to a size too small to see.

The second thing to notice is that the sun is partially obscured by the horizon. I have blown up the sun and drawn a circle around it to show that half of it is below the horizon, out of sight.

Here is the maths that proves this image would be impossible if the earth was actually flat.

That one frame of the video disproves everything else said in it.

Well, I've already addressed the reason why the sun appears to get smaller, and why it is impossible for the sun to drop below the horizon on a flat earth. So I assume you're talking about the part of the video where he "demonstrates" atmospheric refraction and magnification causing the sun and moon to appear to fall below the horizon.

But wait... where is the horizon?

Before he puts the lens in place you can see the "horizon"

After he puts the lens in place, you can't see the "horizon"

What he has done with that lens is zoom in on the top half of the "sky" so that the bottom half can't be seen. Note that before the lens is in place you can see his fingers touching the table and the table receding into the distance. After he puts the lens in place you can see the table at all, and only the part of his hand above the knuckles is visible.

This is not what we see in the real world. In the real world, as the flat earthers like to remind us, we see the horizon rising up to eye level.

Using this lens, he has not demonstrated the sun falling below the horizon, he has simply "moved" the horizon down out of view.

This is a totally unrealistic "experiment" and proves absolutely nothing.

Is there a way to find out how far away the sun is?

Yes, it's called triangulation. For example, Eratosthenes method can tell us one of two things... either the sun is millions of miles away and thus the rays of light hitting us is almost completely parallel and we're on a spherical earth, or the sun is nearby and the rays of light diverge and we're on a flat earth.

If the latter is true, the measured angles tell us the sun must be a little over three thousand miles away.

And those pictures of the sun where the rays/light is coming out of the clouds at different angles

That's the catch. The flat earthers will tell you that perspective is the reason the sun appears to set... but then they totally forget about perspective when they talk about crepuscular rays.

The fact is, those shafts of light are actually nearly parallel, but perspective make them appear to converge.

wouldn't that give the same effect of shadows being cast at different angles?

Yes, it would. As I said, the shadow experiment means one of two things - we're on a spherical earth with the sun millions of miles away, or a flat earth with the sun only 3000 miles away.

So how can we tell which it is? Easy.

With the sun 3,000 miles above the surface, we would never be able to see a sunset. If such a sun did exist and was moving away from us, it's apparent size in the sky would get smaller and smaller until it simply became too small to see. But it would never drop low enough in our field of view to be blocked by the surface.

For it to appear to be that low in the sky, it would have to be hundreds of thousands of miles away from us, and it would then be too small to see.

The simple fact that you can take photo of the sunset over the ocean and see half the sun cut off by the horizon proves that the sun can not be behaving this way.

First, there's no such thing as "the law of perspective" - only a vague phrase used by flat earthers to handwave any evidence away.

Second, it's difficult to even decipher what you're saying here. Railroad tracks are parallel but appear to converge because the angular distance between the tracks decreases as they get further away from you. Crepuscular rays are parallel but appear to diverge because the angular distance between the rays increases as they get closer to you. As objects get further from you, their angular size seems to decrease, and as objects get closer to you their angular size seems to decrease. If you read this carefully, you will recognize that these are saying the exact same thing. This is completely reasonable, yes?

Eratosthenes' experiment works because the light is moving at a different angle to the ground. Not that the rays appear to be in different directions. To explain this, you only have two options: the Earth is flat and the Sun is close and the rays are not parallel, or the Earth is round the Sun is far and the rays are parallel. Comparing the two situations is illuminating:

Since the Sun is always above the surface of a flat Earth, it should always be day on a flat Earth. On a round Earth, sometimes the Sun would be on the other side of the Earth and cast a large shadow called night. Obviously we experience nights, so it seems like a round Earth is more likely since it explains it so simply and so perfectly. However, a flat Earth could theoretically come up with an explanation for how night would happen on a flat Earth. The three explanations I've seen are the following:

1. the Sun moves far enough away that it appears to get blocked by landscape/merge with the ground

2. the Sun moves far enough away that it reaches a "vanishing point"

The first seems plausible - night on a round Earth is explained by the Earth blocking the Sun, so a similar idea might work with a flat Earth, right? Well, not exactly. Flat earthers will say that Eratosthenes' experiment can be explained by a Sun that is about 3,000 miles high and they will argue that the diameter of the flat Earth is about 24,000 miles. The furthest you could be from the Sun on a flat Earth is if you were on Antarctica and across the entire world was the Sun above Antarctica. If you calculate how high the Sun would be above the horizon in that situation, you'll find that the Sun would be about 7 degrees above the horizon - fourteen times the size of the Moon in the sky. That's a best-case scenario - in reality flat earthers say the Sun is approximately over the Equator so the Sun would always be significantly higher in the sky. This explanation simply doesn't work.

What about the next explanation? Flat earthers will say that like railroad tracks appear to converge to a "vanishing point" and their angular size gets smaller, the Sun should appear to converge and its angular size should decrease to a "vanishing point". The problem with this is that the Sun does not appear to change size during the day, especially not from a single point to its full size and then back to a single point. The Sun is about a half of a degree in size - there's not evidence of the Sun continuously changing from zero size to half-a-degree size. The "vanishing point" explanation simply doesn't work, and also demonstrates that the Sun has an approximately constant size throughout the day. You could explain this by saying that the Sun is far away from the Earth so the angular size does not change much, or you could say that the size of the Sun is actually variable. Since we cannot have the Sun be both close and far from the Earth, the first explanation does not work, while also demonstrating that evidence points to a Sun quite far from Earth - even when we try and assume it's not! The second explanation is obviously not true because no one reports wildly different sizes of the Sun at the same time.

...and so on and so on. I think I've wrote enough to ponder for now.

The short version is that you can explain any experiment's results on a flat earth (do not stop reading there!) - the problem is that you cannot coherently explain all the experiments' results on a flat earth. They just end up not being coherent, and you can only take special pleading so far. This is just a microcosm of that problem dealing only with the existence of night at all, never mind the specifics of night and and all the other phenomena seen in the world.

And those pictures of the sun where the rays/light is coming out of the clouds at different angles, wouldn't that give the same effect of shadows being cast at different angles?

The fancy term for those rays is "crepuscular rays." If you take a picture of them from above, this is what they look like.

https://www.metabunk.org/data/MetaMirrorCache/f1f554a724343bc8312bcbb5d02aaccd.jpg

The reason they look like they're angled is due to perspective. It's the same effect that causes straight train tracks to converge as they become more distant.

Now, that image from above the clouds is not a perspective that most of us mere mortals have access to. You would need a high altitude balloon, or plane, or be in space. So, in the interest of additional evidence that you can get from the ground, then how about this.

https://en.wikipedia.org/wiki/Anticrepuscular_rays

Crepuscular rays are the rays you see when you look towards the sun. As you'd expect, they all "point towards" the sun. If you follow those same rays of light as they pass away from you, they also seem to converge to a single point. The anticrepuscular rays converge for the same reason both ends of train tracks converge. The train tracks are parallel and perspective causes them to seem closer together as they become more distant. Same thing with light from the sun.

The light rays are parallel, because the sun is so far away. The light rays seem to converge due to perspective.

I mean, would this same thing happen in a hill?

Yes, and a hill is curved.

I mean, would this same thing happen in a hill?

Yes, it would. If the stick was not perpendicular to the ground, and the ground not level, a shadow would exist. You can argue that Eratosthenes did not properly set up his experiment by ensuring it was flat ground, but you can't argue that the method itself can not work.

Was the well hole perfectly plumb? Was the other object perfectly plumb? And how about the man's strides, how does that error factor come into play?

It comes into play by the fact Eratosthenes did not manage to calculate the exact circumference of the earth. He only got within 15% of the true value.

If everything had been perfect, there was no reason he could not calculate the exact circumference.

Those are fair questions.

The problem is flat earthers go way beyond asking questions into making easily disproved assertions. They do not say "Is the earth flat?", they say "The earth is flat and here is the proof", then refuse to acknowledge that their proof is false and easily debunked.

That's not proof. His results would have been the same if the sun were 3000 miles away and 32 miles in diameter.

Source?

He's right.

But if the sun is 3,000 miles away, we can never see a sunset.

B-b-but something something Newton being a freemason

True. Let's do some maths.

Assume the sun is 3,000 miles above the surface. Assume we're standing 3,000 miles from the position of the sun over the surface. Assume the sun is moving directly away from us.

Let's use this right angle triangle calculator to calculate the angle of the sun above the horizontal.

Edge 'a': 3000 miles
Edge 'b': 3000 miles
Angle 'A': 45 degrees

This means if we were 3,000 miles from the location of the sun, we'd would have to look up at 45 degrees to look directly at the sun.

Edge 'a': 3000 miles
Edge 'b': 6000 miles
Angle 'A': 26.6 degrees

This means if we were 6,000 miles from the location of the sun, we'd would have to look up at 26.6 degrees to look directly at the sun.

Edge 'a': 3000 miles
Edge 'b': 9000 miles
Angle 'A': 18.4 degrees

This means if we were 9,000 miles from the location of the sun, we'd would have to look up at 18.4 degrees to look directly at the sun.

Edge 'a': 3000 miles
Edge 'b': 12000 miles
Angle 'A': 14.0 degrees

This means if we were 12,000 miles from the location of the sun, we'd would have to look up at 14 degrees to look directly at the sun. If the sun was directly over the North Pole, and we were standing on the South Pole 12,450.5 miles away, we'd still have to look up at 13.6 degrees to look directly at the sun.

This means that at no time on the flat earth, can you get far enough away from the sun for it to drop below the horizon. At that distance, the sun would have the same apparent diameter as an NBA basketball 322.6 yards away.

But lets assume that the sun is directly over the South Pole on the opposite side of the flat earth, 24,901 miles away.

Edge 'a': 3000 miles
Edge 'b': 24901 miles
Angle 'A': 6.9 degrees

This means that if the physically impossible happened, and the sun was as far away from us on the flat earth as it can get, we would still have to look up at 6.9 degrees to look directly at it. At that distance it would appear to be about the same size as an NBA basketball 645.2 yards away.

These simple calculations prove beyond doubt that the sun can not be only 3,000 miles above the surface and still allow us to see it set.

The fact we can see the sun set proves that the earth is a sphere.

So, re-do the experiment with more sticks.

Polaris is only view-able in the northern hemisphere only. There are constellations only view-able in the southern hemisphere.

"I would like to give everyone the chance to look at the Flat Earth Theory from a different viewpoint." Ugh, really? Calling people with hundreds of years of science to back up their beliefs "ballers" is insulting.

No, it's really stupid and mildly insulting.

You are so transparent. "Baller" is intentional to be mildly insulting. "Flat earther" is not insulting at all because it's what you believe. So I propose you call yourself a "flat-head". That is much more equivalent, isn't it?

As for Polaris, yeah, you can't really dispute we live on a sphere since only half of the planet ever sees it.

You are very very smart. Congrats.

I know. I'm not easily manipulated by a very weak argument that even a teenager could probably pull off more effectively.

Flat head sounds perfectly accurate. And really not insulting if you think about it, and don't actually have that thought in the back of your mind that the earth really is a sphere. I mean, I'm a proud "dead head". No offense there. 👍

:) Now I'm going to have "Truckin'" bouncing around in my round head all day.

Hahaha love it

You're a ridiculous child, especially since you started this stupid thread and cast insults first. Begone with your disinfo.

It is disinfo, and only very, very stupid people ever believe it.

For your own health

Is that some kind of threat? Stop spreading your lies and I won't comment.

Please just hit "block user" and move on. I'll do the same. You are nauseating.

You weren't asking, you were dictating, and out of the gate insulting rational, educated people.

Why do you continue to speak to me? Go away. You make me want to fucking puke.

Baller is a compliment

That is not how the term is used in the Flat Earth community buy you probably already know it.

Why would the moon and sun be spheres and not the Earth? Especially with so much evidence showing all bodies are spheres including Earth.

Also, what's more likely. Primitive humans thought the earth was flat due to ignorance and pushed it into religious texts or primitive humans figured out more about the universe than modern science.

Yes every flat earth argument should be taken seriously and defeated soundly with actual facts. Also when you think about it if you can't tell someone why the earth is a sphere without saying that you learned it in school or NASA taught you do you REALLY know it? Every one of us should know at least 2 ways to prove spherical earth for when the flat earthers post their little video clips on this sub.

it was just a small analogy and i was sorta trying to downplay it at first due to its short span of time.

i can see where youre coming from.. but being in this sub long enough, i dont doubt TPTB ability to pull a long con. tell a lie so well people cant help but laugh at the truth.. theres an odd quote about that btw.. i dont see it any dif then people using certain mathematical and "scientific" based proofs to talk about anything space related.

i cant accept ball earth until i see a shot of it from space that is a non cgi, non edited, no fish eye, rather raw camera. forget the math. show me a real photo/video. and i mean REAL

i cant accept flat earth until i see something similar...

at this point in time earth may as well be shaped like a kidney bean to me.