The world map was produced using Wermer's projection, an equal-area transformation, which gives a heart-shaped view of the world.

The Mathematica code below shows how it was created.

Needs["Miscellaneous`WorldPlot`"]

Wermer[theta_, phi_] :=
Module[{t},
       t = If[N[theta] == 0,
              phi,
              phi Sin[theta] / theta];
       N[theta {Sin[t], -Cos[t]}]]
       
WermerProjection =
      (Wermer[Pi(5400 - #1) / 10800, Pi #2 / 10800])& ;

WorldPlot[World,
          WorldBackground -> RGBColor[0.340, 1.000, 1.000],
          WorldGrid -> None,
          WorldFrame -> Thickness[0.004],
          WorldProjection -> WermerProjection];
Here is a bigger version of the plot, and another area-preserving map-projection:
Last updated 9th June 1995