Its sherical geometry.
IOn fact there are no straight lines that can be drawn on the earths sevice. Contraru to the popular believe that the shortest distance between two points is a staright line is a myth. Buckminster Fuller pointed this out repeatedly.
The longer the line the more curved it has to be.
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This is not a straight line, it is curved, but it has to be much longer for you to perceive the curvature.
“Spherical geometry”