Hermione Wrote:
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> Anyone who's not come across this before might
> find this article -
> [irna.fr]
> - of interest.

While that's a good article it's orthogonal to mine as it discusses the location at the longest meridian and latitude circle over land. And then there are others who discuss the gravicenter of landmasses. Both are different measurements than mine. That landmass center is of course somewhere inside Earth. Some are then projecting that back to the surface, but that doesn't really makes sense in my opinion.

Mine is only about the land surface of all continents, including Antarctica. That's reasonable as the shortest distance from locations on land to the Pyramid is the interesting metric. That distance is measured as the direct line on the spherical surface of Earth. It's the orthodrome or great circle arc. This is the same distance and center calculation you would do to solve classic optimal location problems, like a classic operations research school problem of finding the optimal location for a central factory in a simplified environment for example.