[AATW]

If it was an article telling us that the systems were using round earth distance the title of the article would be "The Earth is Round!," markjo.

Then why does the article state that the earth is best described as an ellipsoid?  The article is using "round" to mean "sphere".  An ellipsoid is not a sphere.

Only Tom could link to an article which says

3D surface of the earth, which is of course, best modeled as an ellipsoid, not a sphere

and

Web Mercator ... has become, and will likely remain for some time, the de facto coordinate system standard for web mapping applications, because, as mentioned above, it works well for maps depicting the portions of the globe we care about most, and because it performs coordinate conversion faster.

And think the article is evidence for a flat earth 

The article is literally about projections from the real world 3D surface of the globe earth and 2D maps. Were the earth flat you wouldn't need projections, only scale.

[Tom Bishop]

The article clearly describes that those round earth models are pulling values from flat earth planar surveying because they provide more accurate distances. Hence the "The earth is not round!" title.

[AATW]

Other way round, chap.
It’s talking about the best way to map the real world 3D globe onto a flat surface.

You keep saying there isn’t a map and you don’t have the resources to make one. Now you’re arguing the flat earth maps are more accurate?



The article talks about projection.
Why is projection necessary if the earth is flat? Were it so you’d just need scale to make an accurate map. We only need projection because there is no way to represent the curved surface of the globe earth onto a flat map.

[Tom Bishop]

Feel free to look up what NAD84 is, which the article describes as providing more accurate distances. They are flat maps of the earth created through plane surveying.

[WellRoundedIndividual]

You can argue all you want about what the article is using as a reference for distances.  It still has nothing to do with the topic of multiple measurements that were taken by schools all over the earth and that verify that the earth is round.

[markjo]

Feel free to look up what NAD84 is, which the article describes as providing more accurate distances. They are flat maps of the earth created through plane surveying.

First off, there is no such thing as NAD84.  There are NAD83 and WGS84 which are geodetic datums.

Because the Earth is curved and in GIS we deal with flat map projections, we need to accommodate both the curved and flat views of the world. In surveying and geodesy, we accurately define these properties with geodetic datums.

We begin modelling the Earth with a sphere or ellipsoid. Over time, surveyors have gathered a massive collection of surface measurements to more reliably estimate the ellipsoid.

When you combine these measurements, we arrive at a geodetic datum. Datums precisely specify each location on Earth’s surface in latitude and longitude. For example, NAD27, NAD83 and WGS84 are geodetic datums.

[stack]

Feel free to look up what NAD84 is, which the article describes as providing more accurate distances. They are flat maps of the earth created through plane surveying.

Just for the record so we can dispense with the 'utah' article you periodically bring up because you find the title fetching, for one, it's NAD83. For two, maybe you should free to look up what NAD84 NAD83 is:

North American Datum of 1983
As satellite geodesy and remote sensing technology reached high precision and were made available for civilian applications, it became feasible to acquire information referred to a single global ellipsoid. This is because satellites naturally deal with Earth as a monolithic body. Therefore, the GRS 80 ellipsoid was developed for best approximating the Earth as a whole, and it became the foundation for the North American Datum of 1983.

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

What is North American Datum 1983 (NAD83)?
The North American Datum of 1983 (NAD 83) is the most current datum being used in North America. It provides latitude and longitude and some height information using the reference ellipsoid GRS80.

https://gisgeography.com/geodetic-datums-nad27-nad83-wgs84/

Now, back to three-point Eratosthenes experiments.

[Tom Bishop]

Now look up what a datum is and think about why that might be necessary for the flat state plane maps and the other globe models to interconnect and exchange data.

[AATW]

I see you keep ignoring the question about why projection is necessary if the earth is flat

[Tom Bishop]

I see you keep ignoring the question about why projection is necessary if the earth is flat

It's projecting a spherical coordinate system on to a flat map. The spherical coordinate system is an abstraction used to keep all of the flat maps together and interact with the latitude and longitude requests from GPS receivers, users, etc. The underlying flat maps do not use longitudes and latitudes.

[stack]

Here is further experimental evidence. Peruse at your leisure.

https://core.ac.uk/download/pdf/143365111.pdf

I am still waiting on anyone to tell me if there is something wrong or missing in these experiments.

Here's another Eratosthenes-esque experiment that was done by Sly Sparkane and some volunteers. Essentially the experiment teases out how a close-sun doesn't work on a flat earth. A little slow in parts but worth a full view.



 

[Tom Bishop]

Flat Earth Theory says that the sun is a projection on the observer's atmospheric dome of vision. Find a video which tests Flat Earth Theory.
 

[stack]

Flat Earth Theory says that the sun is a projection on the observer's atmospheric dome of vision. Find a video which tests Flat Earth Theory.

Which flat earth theory is that?  And where is the sun being projected from? And what exactly is an "observer's atmospheric dome of vision"? Sounds fantastical.

[manicminer]

Flat Earth Theory says that the sun is a projection on the observer's atmospheric dome of vision.

Have you ever considered the possibility that Flat Earth Theory might be wrong?  Just because something says something, doesn't mean it is right.

[AATW]

I see you keep ignoring the question about why projection is necessary if the earth is flat

It's projecting a spherical coordinate system on to a flat map.

Correct. And this is only needed because the earth isn't flat.
If it were then only scaling would be required

[manicminer]

It's projecting a spherical coordinate system on to a flat map. The spherical coordinate system is an abstraction used to keep all of the flat maps together and interact with the latitude and longitude requests from GPS receivers, users, etc. The underlying flat maps do not use longitudes and latitudes.

Anybody got any idea what Tom is talking about here?  Because I certainly can't figure it out.  Has it been explained where and what the source of the projection is?

[ChrisTP]

It's projecting a spherical coordinate system on to a flat map. The spherical coordinate system is an abstraction used to keep all of the flat maps together and interact with the latitude and longitude requests from GPS receivers, users, etc. The underlying flat maps do not use longitudes and latitudes.

Anybody got any idea what Tom is talking about here?  Because I certainly can't figure it out.  Has it been explained where and what the source of the projection is?

I think he thinks the earth's flat surface has been mapped onto a spheroid then that spheroid projected into a flat map again to show the flat earth (which is massively distorted). Correct me if I'm wrong Tom.

[totallackey]

If it was an article telling us that the systems were using round earth distance the title of the article would be "The Earth is Round!," markjo.

Then why does the article state that the earth is best described as an ellipsoid?  The article is using "round" to mean "sphere".  An ellipsoid is not a sphere.

So, all the crapola cried by RE is wrong?

Are you admitting you guys have been wrong all this time?

And the spheres depicted in the composites are not spheres?

[WellRoundedIndividual]

The projection of the sun is irrelevant to the shape of the earth. Even if the sun is a projection, using the lengths of shadows from 3 points determines that the earth is a sphere.

Are you part of a new society called SP? Sun Projectionists?

[QED]

A spherical coordinate system projected onto a flat map is called a polar coordinate system. The entire azimuthal angle information is lost in the projection. The only other option is to distort the image to preserve the azimuthal information, which results in scale distortions.

This is exactly what happens when a globe is flattened onto a 2D map, Greenland is the notable example of distortion.

Longitudes and latitudes have no existence on a 2D surface - we just call their replacements the  x,y coordinates. In spherical coordinates, they count equal measures of polar and azimuth angles.