Talk:Geographical centre of Earth

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Geographical centre does not depend on type of map projection

I like to explain the issue of presumed dependency of the type of map projection on the calculation of the geographic centre:

For the mathematical and geometrical correct calculation, you don't need any map projection as the data is given as a global elevation model for the complete surface of Earth. That means, you can look up the elevation for every given latitude and longitude directly, without any map projection. That's the type of data I and Woods used for calculation and therefore the result is independent of any projection type. The map on the upper right is of course using a map projection, to be more specific an equidistant cylinder projection, but it wasn't used for calculation, only for displaying the result.

Isenberg (talk) 22:15, 20 November 2012 (UTC)[reply]

I find the statement under “Opposition“ rather odd: since the area of Antarctica is infinite in an equatorial Mercator projection of the entire globe, the latitude of the supposed barycentre derived from a Mercator map would depend on the arbitrarily chosen bounding latitudes. Does the source perhaps refer to the ‘meridian crossing the most land’ notion, rather than the barycentre proper?—Odysseus1479 02:44, 19 May 2013 (UTC)[reply]

Removal of "Opposition" section, but not the content (yet).

This is not an article about the Great Pyramid being the geographic center of the Earth. Therefore, an "Opposition" section simply opposing that assertion is not appropriate. I have moved the sentence to be directly after the sentence it is opposing. Furthermore, I have rephrased the sentence, because starting it with the title of the book made it incoherent. Finally, I have added a disputed tag after "...that the theory that the Great Pyramid was the geographical centre of Earth would only hold true if a Mercator projection is used as the map for Earth..." because as mentioned by Odysseus1479: the area of Antarctica is infinite in an equatorial Mercator projection; therefore, the foundation of that statement seems to be erroneous, which would make it unverifiable. AnonymousAuthority (talk) 18:13, 23 January 2014 (UTC)[reply]

Unclear how this was determined

This article does not make it clear how this location was determined -- assuming that one can locate such a point rationally. One can determine where the geographical center of any continent is, I assumed, by identifying the continent's most extreme geographical locations -- the end-points, if you will -- & use them to locate the center of the continent. But unless one assigns specific places on a globe as "endpoints", one cannot identify any one place as a "geographical center": every point on the globe's surface is at the middle of that surface!

Of course, if this a pseudo-scientific concept, then there is no point in trying to make rational sense of it. -- llywrch (talk) 17:11, 3 March 2014 (UTC)[reply]

It's explained in the opening sentences. Follow the links if you don't know what the terms mean. PrimeHunter (talk) 11:57, 19 September 2014 (UTC)[reply]
The concept is straightforward, but the title "Geographical centre of Earth" is misguided. Earth is a planet, and you can't do centroids on a planet. It should be "Geographical center of Earth's landmasses" or something similar. --
dab (𒁳) 17:23, 22 April 2015 (UTC)[reply
]

erroneous Pseudoarchaeology tag

The Pseudoarchaeology tag is not appropriate. The history section talks about theories held by people who lived before an accurate computer model could be created. No living person is disputing the modern computer based findings; and the topic itself has nothing to do with Pseudoarchaeology or archaeology. AnonymousAuthority (talk) 18:11, 26 March 2015 (UTC)[reply]

The problem is that the 2003 calculation, the one treated as authoritative, was published on the internet by a guy who claims the Great Pyramid was intended to be located at the centroid (implying, idk, space-faring Egyptians? How else would they figure out the precise outline of Antarctica back in the Bronze Age?) and mocks Egyptologists (and pretty much any sane person alive) because "In ignorance of the proven facts, that group, based like a religion on dogmas, believes in the Great Pyramid as a gravesite".
If we don't use the 2003 calculation taken off a crank website, we are left with the 40-year old very rough estimate of 39 N 34 E. --
dab (𒁳) 17:16, 22 April 2015 (UTC)[reply
]

An apparently sane and capable person did the calculation in 2014 and came up with 44.63 N, 28.77 E.[1] But this is also a result we just pulled of a discussion forum on the internet, even though in this case it wasn't found on some batshit ancient aliens website but in a forum for GIS geeks. --

dab (𒁳) 17:21, 22 April 2015 (UTC)[reply
]

Note that the results quoted on this page are quite different from those cited on

AstroLynx (talk) 17:05, 17 April 2016 (UTC)[reply
]

I wouldn’t expect the barycentre of the land surface to be the same as the centre of the “land hemisphere”. The distinction between them is similar to that between the mean and the median or mode of a distribution; the less symmetrical or ‘normal’ a curve it makes, the greater the dispersion of these measures. That said, I think it deserves a see-also, which I’ll go ahead and add.—Odysseus1479 18:10, 17 April 2016 (UTC)[reply]

Semi-protected edit request on 15 June 2016

This sentence: in the region of, Çorum ,World Should change to: in the region of, Çorum, Turkey

This WP article still claims authoritatively that it is the Pyramids of Giza in Egypt, but that is based on a calculation made in the 1860s, that appears to be outdated and dubious. The calculation regarding Turkey is at least more up to date. At the very least, the map in the article showing Giza as the geographical center should be deleted. Jacob D (talk) 06:42, 23 April 2017 (UTC)Jacob D[reply]

 Done and a couple of other vandal changes that had not been cleared up. - Arjayay (talk) 14:43, 15 June 2016 (UTC)[reply]


@Arjayay: Holger Isenberg paragraphy should removed. According a Turkish news website [2], Vandals troll the page. Also, Holger Isenberg is not a scientist. He writes conspiracy theories in his website. AlexandreManette (talk) 14:47, 15 June 2016 (UTC)[reply]

Sorry
reliable the site you have linked is either. I didn't add the Holger Isenberg information, and whilst the article has had vandalism, I don't who is right and who is wrong. You need an experienced editor who speaks Turkish and knows the reliability of Turkish sources. Arjayay (talk) 15:23, 15 June 2016 (UTC)[reply
]
I’ve read the Google Translate version; it’s an opinion piece that generally ridicules the whole notion. Apparently Çorum has been promoting itself on the basis of the Isenberg calculation, which is supposed to be significant for Biblical literalists by combining the longitude of Jerusalem with the latitude of Mt. Ararat. It goes on to criticize WP and Reddit for promulgating the claim, then links to the same StackExchange thread we have in EL, and concludes by remarking that our attention should be ‘centred’ on social and political problems instead of trivia.
I do think the wording of the last paragraph should at least be tweaked: calling the calculation “revised” implies that it’s a direct improvement on Woods’s, for which we should have a secondary source. And considering the discrepancy between the two results I think the “validated” bit is too strong; it should be reworded around “approximate agreement”, “not far from”, or some such phrase. Then again, I wouldn’t object to its removal either, particularly since the cited link appears to be dead.—Odysseus1479 19:13, 15 June 2016 (UTC)[reply]
Actually it doesn't matter what the Turkish site's reporting. The provided reference isn't valid (as in 404 not found, also the main site which is presented in english and german, is just not scientific.). So anythnig related should be removed. 82.222.181.130 (talk) 07:54, 16 June 2016 (UTC)[reply]
Well then, what is the correct geographical center of all land sources on Earth? This needs to be addressed. This WP article still claims authoritatively that it is the Pyramids of Giza in Egypt, but that is based on a calculation made in the 1860s, that appears to be outdated and dubious. The calculation regarding Turkey is at least more up to date. Jacob D (talk) 06:57, 20 April 2017 (UTC)Jacob D[reply]
Not done: The page's protection level has changed since this request was placed. You should now be able to edit the page yourself. If you still seem to be unable to, please reopen the request with further details. — IVORK Discuss 13:31, 23 April 2017 (UTC)[reply]

Unclear definition of the notion

As it stands the concept seems ill-defined.

Either:

  • you approximate the earth to a sphere and take the isobarycenter of all landmasses with assumption of uniform density, in which case the resulting point is obviously within the sphere (and then if you want a point on the surface you can take the closest point in an euclidian distance for example). This does not look like what has been done here.
  • you run your computations on a surface directly, in which case your results depend on where you center your map, i.e. an america-centered map would lead to a significantly different result and so would a pacific-centered one.
  • another way?

My intuition is that what has been done is the second scenario where the map was aligned vertically on the equator and horizontaly on Greenwich, which is an arbitrary convention in geological/geographical terms. At least I feel this requires clarification.

84.6.183.225 (talk) 10:44, 9 August 2017 (UTC)[reply]

It supposedly does the first as the lead says, except it didn't mention that the point is inside Earth and can be projected to the surface. I have added that.[3] I don't know how accurate the calculations are. They were made by the listed sources and not Wikipedia. PrimeHunter (talk) 17:52, 9 August 2017 (UTC)[reply]

Clarifying the first sentence. Mathematician -> Layperson

The explanation of how this is determined is currently "the superficial barycenter of the mass distribution produced by treating each continent or island as a region of a thin shell of uniform density and approximating the geoid with a sphere. The centre is inside Earth but can be projected to the closest point on the surface." What this means, in lay terms, is this: Take the Earth, as a perfect sphere. Flatten out all the landmasses. Elevation is ignored. The "average" position of all the land will be somewhere INSIDE the sphere. Draw a line from the center of the earth, through the "average" point, and to the surface. That's the location being talked about in this article.

I have no idea if any of the computed locations are accurate or not, but I'm far more likely to trust the one done with a computer using modern global satellite maps.

To the "ancient mysteries" oriented crowd. If you throw a dart at the world, you could probably find SOME monument, tomb, or other significant man made object very near the dart. That doesn't mean they built it there to predict where your dart would land. — Preceding unsigned comment added by LordQwert (talkcontribs) 15:42, 20 March 2018 (UTC)[reply]

Doesn't the centre mean equally close to all points on the earth?

Maybe I just don't understand this, but if it's the centre, that means it's equally close to all points on the earth's surface. So, projecting it to the surface shouldn't be possible, or a particular region. Midhaa (talk) 13:17, 30 March 2022 (UTC)[reply]

The centre equally close to all points on land would be the middle of the Earth's core. The geographical centre is the location on the surface where the sum of the distances on the surface to all points on land is minimal.
Isenberg (talk) Isenberg (talk) 01:07, 29 December 2022 (UTC)[reply]