Sorry, but the mapping of the Earth in two circular pieces goes back at least to the 1500s or 1400s. . The difference is that the 1400s & 1500s maps showed two side-by-side circles, making it much easier to use, rather than having it on opposite sides of a disk. . The favorite ancient way to map half of the Earth was the Stereographic Projection. Suppose you place a plane surface in contact with the globe. >From a point on the side directly opposite the contact-point, project, onto the plane, the half of the globe that's closest to the plane. That's the Stereographic projection. . Its date-of-origin isn't known, but it's amcient. One reason for its popularity was its good shapes, and, at any particular point, the same scale in every direcition. Later, in the 18th century, Halley proved that the Stereographic has that property (called "conformality"). . As mentioned above the usual way of displaying the Stereographic was to show two side-by-side circles. And it was, and is, mlre practical to use equatorial-aspect: The two circular maps, each of half of the Earth, are each centered on a point on the equator. . So, sorry, the "new" map isn't new. It's just more inconvenient, having half of the Earth on the other side of the paper. . The article didn't say anything about the map they mentioned, other than that it was a polar map. They didn't say whether it's equal-area, conformal, or neither. (Regrettably, the current fashion for world maps is "compromise" maps that are neither.) . Yes, it's common for people to complain that the Mercator distorts areas. I've got big news for you: Every flat map distorts something. With a conformal map (such as Mercator), at any given point, the scale is the same in every direction, resulting in good small-region shapes, directions, and relative-distances. The opposite would be equal-area maps, on which all areas are in the correct proportion. Obviously, conformal maps and equal-area maps are both useful for different purposes. If you use world maps, you should have both. . With Mercator (or any conformal map) the only distortion consists of differential magnification.. Of course, Mercator's Canada is shaped wrong, due to the huge magnification of its arctic region. But, othet than Canada, the shapes are pretty-much excellent on Mercator. . Anyway, yes sometimes the shadow-receiving surface of a sundial consists of a world-map, chosen so that a nodus-shadow will tell what point on the Earth the Sun is direcly over. The map would have to be on the right projection. Sure, a polar map of suitable projection would serve that purpose on a disk-equatorial map, but the article said nothing about the projection of the map that it mentioned.
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