21

Flat Earth Theory / Re: Latitude and longitude - please enlighten me

« on: June 19, 2020, 02:09:14 PM »

Just to make my position clear .

I am not taking a FE or RE stance on latitude . A survey of length of successive degrees of latitude along a meridian , with respect to the pole star , will give a clear indication of the shape of the land . It's just geometry . If you don't know the distance to the pole then it can be calculated from those results .

This is the point , the results are determined by measurement not theory. Any coordinate system will give unique values to each point but if want them to conform to the real shape of earth then you have to deduce that shape .

No, I get that. I think I understand your position well enough. Without wishing to put words in your mouth, I'd say you were happy enough to accept my proposition 1) - that you can use latitude/longitude in either model to pinpoint an exact position and as for 2) potentially you can determine whether or not you can calculate accurate distance from latitude/longitude, well then, that can be checked/investigated by taking survey measurements along a meridian.

As I said, I was hoping to get a range of opinions from flat earthers on 1) & 2) separately, but not much engagement so far.

22

Flat Earth Theory / Re: Latitude and longitude - please enlighten me

« on: June 19, 2020, 09:07:09 AM »

As far as the southern hemisphere goes, I'd rather stick to the north for now as that's a lot simpler to think about with just Polaris to deal with. Apologies to anyone down south.

Anyway, it's not really different, it just takes a little more effort to determine the latitude since there is no bright star at the southern celestial pole.

I suspect that two issues are commonly being lumped together: 1) Does latitude/longitude give you a unique and unchanging position (irrespective of shape)? 2) Are distances calculated between two points expressed as latitude/longitude correct?

When you lump these together, it's not surprising that FEers will dismiss latitude/longitude as globe based, because it's hard to accept 2) without accepting a globe, but I don't see 1) as being anywhere near as contentious. Somerled has given an opinion, but I'm having to read between the lines a bit to figure out exactly where he (gender based assumption there) stands on 1). I'm really hoping we'll hear from a few more FEers, I'm genuinely interested to understand their position(s) on this and reasoning.

Actually, I don't see how 1) could be rebutted. As you said, latitude can be determined with the position of the celestial pole in the sky, and longitude can be determined by calculating the difference between solar noon in Greenwich and local solar noon. Travel west and solar noon will happen later, travel east and it will happen sooner. Travel north and Polaris will appear higher in the sky until you reach the north pole and you see it directly overhead. Travel south and Polaris will appear lower until you reach the Equator and it appears on the horizon, and if you keep on travelling south you can repeat with the southern celestial pole. Latitude and longitude are not just arbitrary values, they have a meaning that can be easily verified by anybody: this fact alone is already a strong argument for a spherical Earth, both latitude and longitude being angular measurements.

I agree with most of what you say here, but to determine your latitude you measure the distance from the horizon to Polaris and since we don't (or at least didn't hundreds of years ago) know the distance to Polaris, we can't figure out an absolute distance, so it makes perfect sense to me to measure the angular distance and use that. In fact I can't think of any alternative. That angular measurement could be observed on a flat earth just as well. Similar argument for longitude.

So my argument is that just measuring latitude/longitude and asserting this gives you a unique position you can always find your way back to, isn't (by itself) predicated on a spherical earth model. So I think there is potential for agreement between both sides on this point.

I've frequently seen arguments dismissed out of hand with FErs saying things like "oh you're using latitude/longitude, they're based on an assumption of a globe so your argument is invalid". I was hoping by splitting the whole latitude/longitude question into two points, one independent of model and the other not, that I could find out if FErs could at least agree on 1). Unfortunately, with the exception of somerled, nobody else from that side appears to be interested enough to engage, which is disappointing.

Then comes 2). As seen in another thread, values given by online maps are generally accepted as accurate - or at least, no one has proved them wrong. And we've seen they're based on formulas such as haversine or Vincenty's.

Conclusion: we can determine a latitude and longitude of any point on Earth, and we can determine the distance between any two points on Earth knowing their latitude and longitude using a formula that calculates distances on a sphere or an oblate spheroid. It would be a very intriguing coincidence if this worked without the Earth being a globe.

Yes indeed, but I can't imagine many FErs agreeing that distances calculated using spherical trig are going to be valid. iamcpc went to a lot of effort to avoid the obvious conclusion that Bing maps distances are based on a spherical model.

Ideally I'd like to hear a bunch of FErs say "yes, latitude and longitude work and give you a fixed, unique position. No you can't calculate distances with them because...". At least that would clarify their position.

23

Flat Earth Theory / Re: Questions on the latest Space X launch

« on: June 08, 2020, 11:38:28 AM »

first time posting and need some answers.  Honestly, i don't believe the Earth is flat, but I noticed something and can't find answers online.  In fact, it seems like no one has the answers, so I thought I'd check here.

1.  When the space X was in flight, I noticed the view from one side, there was a nice curve to the earth.  On the other view, the Earth was flat.  I don't care about the curve/no curve.  Just why the difference?

Without looking at the images, probably some sort of image distortion. Wide angle lenses such as GoPros often exhibit this kind of thing.   

2.  Why would we not show a large view of the Earth?  Like instead of the camera showing the rocket and a little piece of the Earth, I want to see the whole USA.  I think my samsung could have gotten more than a sliver of the corner of the earth that was seen.  Am I wrong?  How much should we be seeing at 60K feet.

At 60K feet? You're not going to see a lot. At 40K feet in an aeroplane, how much of the world do you see out of your window? To view the earth properly (i.e. to see something close to a complete hemisphere), you need to be thousands of miles away. Try putting your Samsung a few mm from the surface of a desktop globe and see how much you can capture.

4.  The the boosters landed, they like lose the signal and then it comes back after they landed.   

The landing platforms on the ocean broadcast to a satellite and have to be very precisely positioned. When the rockets get very close they literally rock the boat. Imagine watching satellite TV and someone suddenly starts shaking your house around. The dish simply loses lock for a brief period. There are ways they could get around it, but it's not worth the effort. Cameras on the platforms record the whole thing anyway, so they're only losing a few seconds of live broadcast. Of course if you're looking for a conspiracy, it looks suspicious, but it really isn't.

24

Flat Earth Theory / Re: Flat Earth at the Beach

« on: June 03, 2020, 08:47:41 AM »

- If you go to a lake or other landlocked body of water on a calm day, rather than an open ocean, you will often see further than should be possible, invalidating the 'sinking ship' proof.

Is there some fundamental difference between the water in a lake and in the sea then? What is it?

- Watching the Sun move leads us to the direct conclusion that the Sun moves. It does not lead us to the direct conclusion that the Earth is moving. Likewise, watching the light of the Sun set into the Earth leads us to the conclusion that its light has set into the Earth, rather than the Earth moving any way in particular.

When I wake up from a snooze on an aircraft at cruising altitude in smooth air, I have no sensation of moving whatsoever. I look out the window and see what? The earth is moving slowly beneath me? Should that be my direct conclusion? Is that what I'm supposed to think? Because that inevitably leads to the conclusion that the earth is indeed moving.

In ancient times, the fastest anyone could travel short of jumping off a cliff was by horse. It would be easy to conclude, from riding a galloping horse, that speed can be felt and you'd know if you were moving, that's just common sense unless you know better. Put an ancient Greek on an A380 with the blinds down and try convincing them that they were travelling at 20x the speed of speed of a galloping horse, they wouldn't believe you for a second.

Growing up in the modern world gives you access to a range of different experiences which allows you to rationalise what you see in ways which would confuse someone from the distant past.

Personally, from experience, I'd look at the sun "moving" across the sky or looking down at the ground from an aeroplane and say, at least one of us is moving, no way of knowing which one (or neither) is stationary, however from what I've been taught and from other evidence I find credible, I'm inclined to believe that the earth rotates.

25

Flat Earth Theory / Re: Latitude and longitude - please enlighten me

« on: June 02, 2020, 03:07:23 PM »

About GPS - a math model based on assumed globe . That's the point . All surveys are geometric . The shape of earth will be revealed by this method. Why would you use GPS.

If you trust that a GPS device would give you an accurate value for your latitude, you might as well use it. If you don't, or you want to avoid criticism, then either don't use a GPS at all or use it to cross check against another method e.g. angle of Polaris. For myself, I would be happy to just use a GPS device. To convince others, I would probably use a GPS and some other method and record both results for comparison. For a small extra effort you're conducting a secondary experiment comparing GPS with whatever other method you are using. Two for the price of one.

All geometric survey then is subjected to the method of geodesy i.e. spherical calculation for the purpose of mapping the results onto globe  - it's math modelling again .

GPS could be nothing more than a program designed to remove the spherical calculations to give back the geometric survey results , we could check that after the geometric survey results have determined the shape.

Makes sense.

26

Flat Earth Theory / Re: Latitude and longitude - please enlighten me

« on: June 02, 2020, 01:15:08 PM »

About 1. Latitude/longitude gives a unique unchanging position with respect to where you are on earth . The distance between each degree of latitude is dependent on the shape of earth .

That's geometry , not FE or globe theory - a survey along a meridian with respect to the pole star will give the geometric shape whatever that is. That is all that needs to be done .

Thanks, that's clear enough, I believe I understand your position on this and agree with it entirely.

GPS is not based on a globe earth

Given the rest of what you say, I'm not sure I understand that.

 - it is based on an elipsoid math model we are told.

Agree, but an ellipsoid model of the globe surely?

It's not needed for long/lat.

Agreed, but it can be (amongst other things) used to determine or verify your position in terms of latitude/longitude. For that purpose, I'd say it was accurate enough and a lot quicker and more reliable than the older more traditional methods.

27

Flat Earth Theory / Re: Latitude and longitude - please enlighten me

« on: June 02, 2020, 11:28:47 AM »

Robin, this is something I have wondered for a while too. How is Latitude and Longitude a round earth coordinate system as is sometimes claimed here.

As you say if in the northern part of the world you go to a particular place and measure the angle to Polaris it will always be the same, and we call that Latitude and measure it in degrees. If you move North the angle increases and if you move south it decreases.
In the southern part of the world there is a similar spot in the sky that can be used, it is not marked with a convenient star like in the north so it is not as straight forward to make the measurement.
The range of this measure is from 90 degrees North through 0 degrees to 90 degrees South.

As you also say Longitude can be measured in time offset. Again in the northern part of the world how long after the sun is due south from a reference point (Greenwich) is it due south in your location. All you need to measure this is a timepiece set to Greenwich time. This can be measured in hours or minutes for example.

Using these two measures should give a unique and consistent coordinate pair for any location on the Actual Earth.

The only concession to a circular world (either globe or disc) is in the representation of Longitude not in hours or minutes but rather in four minute increments and refereed to as degrees. This is based on the 24 hours for a cycle of the sun to complete one circle above a disc earth or the earth to complete one rotation in the globe earth. Either way 1/360 of 24 hours is 4 minutes.

I think your main question is, do Flat Earthers agree that these two basic observational measures give a location coordinate pair (latitude and longitude) that is unique and unchanging for a given location on the Earth?

Further that given an latitude and longitude for a location it would be possible to navigate to that point using only the measurement techniques described above. You may not know the distance or the direction, but you could travel north or south to get to the correct latitude, and then travel east or west to get to the right longitude. Not the most efficient path, but it would get you there.

This is exactly right and precisely what I'm trying to get to the bottom of. I suspect that two issues are commonly being lumped together: 1) Does latitude/longitude give you a unique and unchanging position (irrespective of shape)? 2) Are distances calculated between two points expressed as latitude/longitude correct?

When you lump these together, it's not surprising that FEers will dismiss latitude/longitude as globe based, because it's hard to accept 2) without accepting a globe, but I don't see 1) as being anywhere near as contentious. Somerled has given an opinion, but I'm having to read between the lines a bit to figure out exactly where he (gender based assumption there) stands on 1). I'm really hoping we'll hear from a few more FEers, I'm genuinely interested to understand their position(s) on this and reasoning.

28

Flat Earth Theory / Re: Latitude and longitude - please enlighten me

« on: June 01, 2020, 10:23:09 PM »

Sorry Robin , I misread your OP about distance to Polaris .

Measuring distances between degrees of latitude taken from the North star will give systematic difference on FE . Surveying these distances along a meridian will indicate which model is closer to the truth.

That the equator is given as 0 degrees midway between the globe geographic poles is an assumption used to model earth as a globe.

In practice it should be possible to survey the distance closely enough to give a true distance between the geographic N pole and the equator since at the pole you are directly beneath the pole star , and at the equator you are directly beneath the path of the sun at equinox .

If you surveyed a fair distance , say from 70N to 40S if possible then you could extrapolate distance southwards to the equator  - make a prediction then check this with survey. It becomes harder to track the pole star accurately at lower elevations as you travel towards the equator but the predicted position could be checked against the real one .

This is the simple way to determine the shape of earth . Hope this makes sense

The longitude positions used by gps should be the same in both models but latitudes will differ with shape although by how much will be given by survey .

OK, so I hope I've understood your position correctly. You seem happy to accept a position expressed as a latitude/longitude would identify a unique location whatever the shape of the earth and seem OK with the idea of using GPS to obtain a position fix too. That's really what I'm trying to establish, just to see if there is common ground here and it sounds like there is. Any idea whether this is a generally held view within FE? For me, one of the biggest difficulties is understanding where the common ground is in order to have a rational discussion about anything.

I completely agree that if we accept latitude/longitude positions as meaningful and (reasonably) accurate, then measuring a degree or so of either or both would support one model over another. Where we no doubt disagree is that I think these measurements have already been taken and they point to a globe earth.

29

Flat Earth Theory / Re: Latitude and longitude - please enlighten me

« on: June 01, 2020, 01:39:46 PM »

Degrees of latitude have no meaning whatsoever on a flat plane. All you've measured is the angle to polaris. Where would you draw the angle of latitude?

Also, you've skipped completely over people in the South, and how to determine longitude.

Here is the problem I'm trying to get to the bottom of. Latitude and longitude are typically dismissed by FEers because they are routinely associated with the despised globe model. I'm trying, for the moment, to unpick that association and ask whether or not you can use latitude and longitude simply to identify a unique location on the earth. From that viewpoint, if we don't care about meaning, does measuring the angle to Polaris on its own - irrespective of model, distance to Polaris, whether or not light travels in straight lines etc. etc. - locate you along a north-south line and when combined with latitude, does that give you a unique location?

I totally get that when you then start talking about distances and whether or not latitude lines are equally spaced, that causes difficulties with the globe vs. flat models. But fundamentally, is there anything wrong (from the FE perspective) with latitude and longitude as an indicator of position?

I'm just not clear what the consensus is (if there is one of course) amongst FEers on this issue.

As far as the southern hemisphere goes, I'd rather stick to the north for now as that's a lot simpler to think about with just Polaris to deal with. Apologies to anyone down south.

30

Flat Earth Theory / Re: Latitude and longitude - please enlighten me

« on: June 01, 2020, 11:57:01 AM »

Degrees of latitude can only be equidistant on a perfect sphere with parallel light rays from an extremely distant North star.

I should imagine that light bends in an electromagnetic field - problematic because we don't know the true nature of light -and there's  atmospheric scattering/diffusion etc.

The coordinate system of gps is based on a math model , not the real shape of earth .

Again I agree with all of that, but does that mean latitude and longitude can be used to identify a (unique) position and the problems only arise when you then try and use this as a basis for determining distances? For example, I'm quite satisfied that if you were to give me an arbitrary position in terms of latitude/longitude within say 50 miles of my house, then I'd be able to find my way there and send you a photo and you'd agree we were talking about the same place.

31

Flat Earth Theory / Re: Latitude and longitude - please enlighten me

« on: June 01, 2020, 11:51:03 AM »

Good description of how we can measure lat and long in the northern part of the world.

However you state the globe theory preconceived assumption that Polaris is at an extreme distance thus its light rays are basically parallel leading to the conclusion that any change in measured angle of elevation to the star is a product of the curvature of this globe .

No I've not stated anything about the distance to Polaris (extreme or otherwise), other than simply saying that in times past, the distance was not known, but we can however use an angular measurement instead, which works independently of distance. For instance I can measure the angular height of a tree at the bottom of my garden from my current position. It doesn't tell me anything about the actual height of the tree or how far away it is or for that matter, what shape the earth is.

Equally, it doesn't matter whether the light rays from Polaris are parallel or not, just that whenever you measure the angular elevation of Polaris from the same position, you are always going to get the same value and if you move north or south of that position, you will get a different value, which will increase as you move north and decrease as you move south.

It is possible to determine the approximate shape of the earth through the use of precision scientific instruments , sextants , quadrants , zenith sectors and use of geometric surveying technique.

Survey along a meridian and the shape will reveal itself as distance between successive lines of latitude are measured, as will the approximate distance to the pole star - be it near or far.

Geodesy is the applied mathematical method used to map plane geometric survey results onto a sphere .  In itself it is not a science .

Geometry is is the measure of earth as the name implies .

I agree with all of the above, however that's jumping ahead somewhat for me, as I'm simply at this point trying to get to the bottom of the objections raised regarding latitude and longitude.

32

Flat Earth Theory / Latitude and longitude - please enlighten me

« on: June 01, 2020, 10:03:35 AM »

I've read a number of posts where latitude and longitude are dismissed by FErs because they are based on a globe earth.

I'd like to unpick this and ask what the actual objections are.

Fundamentally (if you live in the northern hemisphere), your latitude is easily determined. It's simply the altitude of Polaris from your location. It's not an absolute value in miles, km or light years, because to determine that you'd need to know how far away Polaris is and in times past, that wasn't possible to determine. What we do instead is measure the angle from the horizon to the star, because that's easily done and doesn't require you to know any distances.

Longitude is based on time. When was the sun due south at your location compared to when it was due south in Greenwich UK? If that's +1 hour and the sun moves at 15 degrees per hour, then your longitude is 15W.

Both of these are determined easily from the positions and movements of celestial bodies and can be measured with simple instruments (if you consider an accurate timepiece to be a simple instrument).

Neither of these values rely on any preconceived assumption about the shape of the earth.

There is an issue of course if you want to calculate the distance between two points given by latitude/longitude, because that involves spherical geometry and includes an assumption about the shape of the earth.

So is that it? Are latitude/longitude OK by themselves, but the distances are not? What are the actual objections?

33

Flat Earth Theory / Re: Are plane tickets real?

« on: May 19, 2020, 03:35:42 PM »

I’m not shocked to come back to this thread to find it has eroded from deciding whether or not plane tickets are real

Well the conversation really should have been over when I posted the results from the plane flight super thread earlier on. I felt that answered pretty much all of the questions/issues with how flight times/distances don't support the flat circle model. If that's not enough then there are other forums in which a more active member claimed in regard to southern hemisphere flights which weaken the flat circle model:

There is a whole array of responses from many different view points about the whole flight times/paths/distances don't support the flat circle north pole center model. My response is that I believe these flights are real and that they weaken the flat circle north pole center model. The question was asked, dozens of possible answers were given. End of discussion.

I looked at the plane flight super thread links you posted soon after you posted them. At the time I don't think you actually said what your position was, just that the question had been discussed at length. Pretty much all of the links you posted seemed to be Tom Bishop saying something and everybody else saying "no that's wrong", so I didn't get a clear picture from that what your position was and what I was supposed to conclude from the super thread, other than there was no agreement reached (hardly a surprise).

To be honest, your position confuses me a lot. You seem to sit very much on the fence, sometimes appearing to side with flat earth and sometimes not. Even after all this time, I really have no idea what shape you would pick for the earth if you had to pick one.

34

Flat Earth Theory / Re: Are plane tickets real?

« on: May 14, 2020, 02:58:19 PM »

Just to get back to haversine for a moment. The mathematical haversine formula works by first calculating the central angle, θ, between two arbitrary points on a sphere. Then with the central angle determined, you work out the great circle distance between them. So a very simple example would be, what's the distance between 45°N, 10W and 46°N, 10W. Well the central angle, θ, is exactly 1°, so that bit is simple. All we need now is to work out the great circle distance. And that's easy too, it's πrθ/180 and that's an absolutely precise and correct mathematical solution to the problem. Unfortunately, it's useless. "Just drive north a distance of πrθ/180 and you'll be at your destination". To be of any use whatsoever, we need actual numbers for answers, so let's go ahead and assign a value for r of 6378.137km, but what do we use for pi? How many of the infinite decimal places do we need?

That's the problem with this, you can have an absolutely precise mathematical answer - πrθ/180 - or you can have an approximate, rounded actual value, e.g. in this case if we take pi to be 3.14159 then the answer is approximately 111.32km. You just can't have it both ways.

35

Flat Earth Theory / Re: Aristotle's most famous proof for the rotundity of the Earth

« on: May 09, 2020, 09:15:34 PM »

Read the OP again. At a certain position near the light source, like in RE, straight line shadows maintain a straight line. Shapes maintain their shape on the Moon and do not warp.

Since in the real eclipse the shape of the shadow on the Moon does warp, this falsifies the explanation given.

You can't have it both ways.

The experiments (both the original and my own) are not especially true to life. For example, in reality, the observer is going to be stationary on the earth, whereas in these experiments, the observer is stationary and the earth (the folder) moves back and forth in front of a stationary light source. Furthermore, I don't think anyone has ever suggested a rectangular folder is a sensible model for the earth.

Probably a more realistic model would be to replace the folder with a stationary sphere of a sensible size, locate the observer on the sphere and move the light source to create a moving shadow. Something easier to do in a model than with real objects in a real room. My models are simply intended to mimic a real experiment as documented in the Wiki.

Aristotle's basic point surely is that only a sphere can be rotated about any arbitrary axis and still cast a shadow of exactly the same shape. Certainly any flat surface, whether circular or some other shape, when put in front of a light source and projected, will create a variety of shadow shapes as it is rotated about various axes.

How these shadows then interact with a spherical object (the moon) is interesting, difficult to visualise, but perfectly possible to model.

However my original point is simply that the image in the Wiki is misleading and unrealistic due to the placement of the light source, the folder (representing the earth), the observer and the moon globe. Because it is misleading, I don't believe (on its own) it is good enough evidence to dismiss Aristotle's ideas.

36

Flat Earth Theory / Re: Aristotle's most famous proof for the rotundity of the Earth

« on: May 09, 2020, 03:56:22 PM »

Doubt whether Aristotle stated anything that is attributed him. Only fragments of his work survive - parts of about 30 manuscripts. Most of what we are told we know of his works comes from medieval manuscript transmission - Corpus Aristotelicum - and from Bekkers interpretations of these interpretations.

 A bit like the Eratosthenes crap , none of whose work survived, whose main source is a book published by a Greek astronomer who we know nothing about but may have lived anytime from 200bc to 2 or300ad if I remember correctly. .

Funny how all the globey bits of lost manuscripts survive.

Yes, but it's the argument which really matters, not who made it. It's convenient to attribute the argument to someone because then you have a label to use and in this case, it's Aristotle. That these ideas have survived at all in any form is a minor miracle. It's much the same with Shakespeare, there are many arguments about who exactly he was and which if any of his plays were actually written by him. And he's much more recent than Aristotle.

37

Flat Earth Theory / Re: Aristotle's most famous proof for the rotundity of the Earth

« on: May 09, 2020, 03:49:54 PM »

Thanks, that's interesting. So you verify that if the shadow is coming from a slightly different angle than the observer, the curvature would occur. If the shadow were exactly  coming from the observer's location, the curvature would not occur.

I'd baulk at the idea of 22 degrees being called slightly in this context. I didn't position the observer very precisely in the model (in the 3rd image), just approximately in line with the folder representing the Earth, so there may still be some curvature, but as you can see, it's not discernible. The main point I'm making is that the original image is misleading because the observer is a very long way away from where they could be in reality. In reality, I think they could only be around +/- 1 degrees or so from the centre line joining the light source and the centre of the moon (because I believe the Earths diameter as seen from the moon is around 2 degrees - so half that).

Is there any reason to assume that the shadow is coming directly from the observer other than because that's what RE says?

Well it's more that the intent of the image is to undermine the RE model, so I think in this case, it's fair to accept the parameters of an RE model (for the sake of argument) in order to then attack it.

Your model with a curving shadow seems to disprove Aristotle's claim that only a round object can cause a round shadow. We see a round shadow. It seems appropriate to say that Aristotle was wrong, and that a flat-sided shadow can project as round on a round moon.

I imagine Aristotle took it for granted that his readers would understand that he intended that the observer would be located somewhere on the Earth, not tens of thousands of miles away. Yes this experiment shows that if you observe from a location way out in space, you would see something very different and much more obvious to that observed by someone on Earth.

38

Flat Earth Theory / Aristotle's most famous proof for the rotundity of the Earth

« on: May 09, 2020, 08:04:04 AM »

A couple of weeks ago I saw this post from Tom:

Aristotle's most famous proof for the rotundity of the Earth is the Lunar Eclipse. He said that only a round Earth could cause a round shadow. Since the shadow is round, the earth must also be round. However, he was incorrect, and apparently did not experiment much with that idea. Due to the shape of the Moon, a flat sided shadow can also cause a round shadow to appear:

The image is taken from https://wiki.tfes.org/Lunar_Eclipse_due_to_Electromagnetic_Acceleration

I was surprised that such an apparently simple experiment could so utterly demolish Aristotle's argument, so decided to have a go at repeating it myself. I couldn't find a very suitable spot at home, so decided to model it instead. Here's what I came up with:



However, in modelling this, I discovered something quite interesting. If you take a close look at all the shadows (not just the moving shadow), you'll notice that whilst the observer is more or less directly in front of the alcove, the light source (a torch) is coming from somewhere off to the left and above. That's the only explanation for these shadows. And since "the Earth" (a rectangular folder in this experiment) is blocking the light source, then it too must be off to the left and above. I worked out that looking back from the moon, the angular separation between the Earth and the observer needs to be approximately 22 degrees.

In RE terms, that means the observer is located in space approximately 90 thousand miles from the Earth.

So not very realistic then.

I then moved my observation point to where the folder is to simulate an Earth bound observer. This is what I see now.



So not such a devastating demolition of Aristotle at all, just a very misleading image in the Wiki.

39

Flat Earth Theory / Re: Are plane tickets real?

« on: May 05, 2020, 09:30:40 AM »

My point is that it's not robinofloxely who is being held to this standard of accuracy. It's the testing of the mathmatical formula which is being held to a high degree of precision which I have explained several time

I guess I'm with ChrisTP and Nosmo on this, I'm really struggling to understand your point. I know you've tried to explain to us several times, but I'm just not really getting it.

Computers and maths are two different things. Maths doesn't have to live in the real world so things like π and √2 and ∞ are nothing special and the fact that their values can never be written down as actual numbers is an irrelevance. My favourite mathematical formula is:
e^iπ = -1
Now you can't just plug in values for e, i and π and work this out, but it is nevertheless true.

Computers are just machines for performing calculations, nothing more. You can't just hand a computer an equation like that and expect it to solve it.

What you can do is take a mathematical formula and use it as a basis for some computer code to calculate a result from a set of values. The code is not maths, the syntax is not the same for a start. What we're comparing in this thread topic is not maths and computers, but two separately written bits of computer code which do something. The something they do is claimed to be the same thing, whatever name you like to give that thing is up to you. We're all referring to it as haversine, but if you object to that, fine let's call it Nigel instead. So now we have Bing and ourselves implementing Nigel. Do they really? Well we can just feed in endless different values to each one and every time, the two Nigels agree with each other 100% (and don't forget, the most recent code does away with all rounding, so that's no longer an issue). So Nigel1 and Nigel2 are in complete agreement with each other, always. They are identical twins.

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Flat Earth Theory / Re: Are plane tickets real?

« on: May 02, 2020, 09:23:26 AM »

A Car odometer, a device that measures to the one tenth of a kilometre, (one tenth of a mile in the UK or USA), so not very precise. They also generally measure distance based on the rotation of a wheel, whose diameter and circumference vary over time (as tyres wear), so also not exactly accurate.
This seems to be quite a different standard to the one Robinofloxley is being held too.

I must say Robin that I have enjoyed your explanation and work in this thread, it is an example of the unexpected educational threads that pop up from time to time.

Thank you for saying that, I'm glad you've enjoyed it. I've learned quite a lot myself putting it all together and have enjoyed doing it.

I do think iamcpc has a somewhat varied standard when it comes to evaluating evidence. He believes Bing distances are based on measured distances in the real world and take into account elevation. No evidence has ever been given for this belief, so unless he's holding something back, that's a strong belief based on zero evidence, however when it comes to this whole haversine business, there's a mountain of evidence now and he's still a very long way from being convinced.