Quote from: Tom Bishop on April 19, 2019, 05:21:41 PMQuote from: stackIf I'm to understand this, FECORE's one 'experiment' funded by membership so far (No other experiments have seemingly taken place) found that, for instance, the 10's of km's in distance measurements show the WGS84 to be off by 6 inches at the shortest distance and less than 2 feet at the longest? Am I mistaken in interpretation? https://wiki.tfes.org/World_Geodetic_System_1984Nothing in the wiki article addresses the fact that FECORE basically validated WGS84. And we all know that the WGS84 is based upon the ellipsoid. Even the Utah article you always cite with the catchy Title, "The Earth is Not Round!", is actually referring the fact that it isn't round, it's an ellipsoid. From the article:"NAD83 became the statewide datum standard beginning in 1997...UTM NAD83 is a projected coordinate system that represents physical locations abstracted to a flat, cartesian coordinate system. The UTM NAD83 projection uses the GRS80 ellipsoid and a center-of-the-earth anchor point as its datum, both of which are slightly different than the WGS datum." You really should clean up that wiki entry, it's wildly misleading verging on being outright disingenuous.
Quote from: stackIf I'm to understand this, FECORE's one 'experiment' funded by membership so far (No other experiments have seemingly taken place) found that, for instance, the 10's of km's in distance measurements show the WGS84 to be off by 6 inches at the shortest distance and less than 2 feet at the longest? Am I mistaken in interpretation? https://wiki.tfes.org/World_Geodetic_System_1984
If I'm to understand this, FECORE's one 'experiment' funded by membership so far (No other experiments have seemingly taken place) found that, for instance, the 10's of km's in distance measurements show the WGS84 to be off by 6 inches at the shortest distance and less than 2 feet at the longest? Am I mistaken in interpretation?
The article goes over what the anchor points and datums are. "The Earth is Not Round!" sounds pretty clear to me. If the article was about WGS84 distributing round earth measurements the title of the article would be "The Earth is Round!"QuoteGeographic coordinates use latitude and longitude values to define positions on the 3D surface of the earth, which is of course, best modeled as an ellipsoid, not a sphere....Latitude and Longitude are useless for measuring distance and area...Web Mercator's significant weakness is that measurements of distance and area in its native coordinates are completely unusable.It says that RE is based on longitude and latitude. The article then says that latitude and longitude are not used.I would recommend taking it to another thread, as it is off-topic to the subject of gyroscopes and is distracting. Please start a new thread and tell us how this system works if latitude and longitude measurements are not used. I am sure that several others in the community would like to know.
Geographic coordinates use latitude and longitude values to define positions on the 3D surface of the earth, which is of course, best modeled as an ellipsoid, not a sphere....Latitude and Longitude are useless for measuring distance and area...Web Mercator's significant weakness is that measurements of distance and area in its native coordinates are completely unusable.
Seemingly the argument is that the ellipsoid based earth model/datum is inaccurate when it comes to flat maps. I guess, therefore flat maps are the real representation of the shape of the earth, flat? I’m guessing b/c I’m not really sure exactly what the wiki entry is arguing for. But I guess if my guess is correct, then it might be easy to create a flat earth map by simply pasting all these State Plane type maps together and boom! Flat Earth map.
Quote from: stack on April 19, 2019, 10:35:22 PMSeemingly the argument is that the ellipsoid based earth model/datum is inaccurate when it comes to flat maps. I guess, therefore flat maps are the real representation of the shape of the earth, flat? I’m guessing b/c I’m not really sure exactly what the wiki entry is arguing for. But I guess if my guess is correct, then it might be easy to create a flat earth map by simply pasting all these State Plane type maps together and boom! Flat Earth map.How anyone can claim that an accurate map which depicts the earth as a flat plane does not exist when literally when literally BILLIONS of people every year, myself included, navigating the earth using a map which depicts the earth as a flat plane. I've linked dozens of them in this thread. It all goes back to the core there is no TRUTH.
You can't say that TRUTH is absolute when no one has been able to present one thing which is TRUE. People presented things that very likely could be TRUE. They also have a very small likely hood of being FALSE.
Quote from: iamcpc on April 19, 2019, 10:31:39 PMYou can't say that TRUTH is absolute when no one has been able to present one thing which is TRUE. People presented things that very likely could be TRUE. They also have a very small likely hood of being FALSE.Again, truth is independent of your or my ability to discern what the truth is.Person A believes the lion is outside, Person B does not - despite being able to see the lion through the window, he believes it’s a mirage or a model lion or whatever.If Person A and B both go outside then their fate is the same because the truth is independent of their beliefs.Dragging this back to FE, the shape of the earth is what it is. The truth of that is independent of your beliefs about that, or mine.
Here is one for ya.Johannesburg to Sydney - 11.75 hour flightLos Angeles to Shanghai - 13.5 hour flightWhich one of these looks further?
As there is no flat earth map I thought I'd have a go at making oneI had a look on Google Maps and used that as my source for distances between places.Obviously if you don't accept those distances as accurate then that's going to be a problem from the start but given that Google Maps is used by millions of people to get around you'd think we'd know about it if their maps were wrong.I took some US Cities - I used mainland US partly because it's continental so we get away from complexities about measuring distances across oceans. I picked them fairly arbitrarily but I wanted them far apart as this is where we should see most difference between a flat earth and a globe.I started with Seattle. Final image is at the bottom of this post.The distance between Seattle to New York is 2405 MilesSo I drew a black circle diameter 2405 pixels. Seattle is the centre. New York must be somewhere on that circle.New York to Dallas is 1368 miles. I picked an arbitrary point on the circle surrounding Seattle - to the right of the circle as New York is due East of Seattle. I called that point New York and drew a red circle 1368 pixels around that point.So Dallas must be somewhere on that red circle.Seattle to Dallas is 1684 miles so I drew another blue circle around Seattle of diameter 1684 pixels. Dallas must be somewhere on that blue circleSo, Dallas must be on the intersection between the red and blue circles. There are 2 possibilities as the circles intersect in 2 places. Dallas is south of both New York and Seattle though so I've picked the lower one and called that Dallas.So now we know where Seattle, New York and Dallas are in relation to one another. I've marked the cities with rough X's and labelled them.Now what happens if we add a 4th city? I picked Minneapolis as it is fairly central to the above 3 cities.The distance from Minneapolis toNew York is 1020 milesSeattle is 1384 milesDallas is 1389 miles.So I've drawn green circles with the corresponding number of pixels around those 3 cities.Minneapolis must be somewhere on each of those green circles so it must be at the intersection of them.The problem is the three green circles don't all intersect at any point. So either:1) The distances on Google Maps are wrong2) I have made an error somewhere in my reasoning or method3) The earth isn't flat.Are there any other possibilities?
Do you have a citation for this sweeping generalisation?
I repeated the above for a few cities in the UK - I even repeated the error, I used the distances as the diameter, not the radius.I'm not going to post all the details, you can check the distances for yourself.Interestingly, here we do get a point where the green circles meet which must be where Oxford is.My conclusion from this is1) The method I am using is valid2) The distances as given by Google Maps are likely to be accurate.3) The difference between a flat earth and a globe earth in terms of accurate mapping is less noticeable over smaller distances, which is as you'd expect.
I did this exercise using Google Sketch-up and published mileage from the airlines. The results were as expected. North of the equator it worked reasonably well but it collapsed when southern cities were attempted.
these waves of smug RE'ers are temporary. Every now and then they flood us for a year or two in response to some media attention, and eventually they peter out. In my view, it's a case of "if it ain't broke, don't fix it".
Quote from: TomInAustin on May 03, 2019, 04:57:06 PMI did this exercise using Google Sketch-up and published mileage from the airlines. The results were as expected. North of the equator it worked reasonably well but it collapsed when southern cities were attempted.Since 90% of humans live in the Northern Hemisphere, flat earth maps must be convincing only above the equator. Obviously an Australian would be offended to see his island warped as it is in Rowbotham's map.
Quote from: Bikini Polaris on May 04, 2019, 12:27:18 AMQuote from: TomInAustin on May 03, 2019, 04:57:06 PMI did this exercise using Google Sketch-up and published mileage from the airlines. The results were as expected. North of the equator it worked reasonably well but it collapsed when southern cities were attempted.Since 90% of humans live in the Northern Hemisphere, flat earth maps must be convincing only above the equator. Obviously an Australian would be offended to see his island warped as it is in Rowbotham's map.Pull up Rowbotham's map. Australia is it's normal size there. The map you usually see online is a globe projection.
Tom is wrong most of the time. Hardly big news, don't you think?
Pull up Rowbotham's map. Australia is its normal size there. The map you usually see online is a globe projection.
Quote from: Tom Bishop on May 11, 2019, 04:08:02 AMPull up Rowbotham's map. Australia is its normal size there. The map you usually see online is a globe projection.Tom, can you please be dear and post here two easy things, according to FE map:1) The direct physical distance from Perth to Sidney in Australia2) The direct physical distance from Perth (AU) to Cape Town in AfricaThe numbers don't need to be very precise, any 10 km error is acceptable.