![]() It is contrasted with true north (the direction of the North Pole) and magnetic north (the direction in which a compass needle points). Grid north ( GN) is a navigational term referring to the direction northwards along the grid lines of a map projection. Otherwise, negative northing and easting values indicate a position south and west of the origin, respectively. To ensure that the northing and easting coordinates on a map are not negative, map projections may set up a false origin, specified in terms of false northing and false easting values, that offset the true origin. Usually associated with a map projection is a natural origin, e.g., at which the ellipsoid and flat map surfaces coincide. This permits users to shorten the example coordinates to 949-361 by concealing 11U 05nnn34 56nnn74. Because the (leading) most significant digits specify the part of the world and the (trailing) least significant digits provide a precision that is not needed in most circumstances, they may be redundant for trekking use. Subset conventions can also be used, such as a truncated grid reference, where the general location is already known to participants and may be assumed. The pair is usually represented conventionally with easting first, northing second.įor example, the peak of Mount Assiniboine (at 50★2′10″N 115☃9′03″W) in UTM Zone 11 is represented by 11U 0594934 5636174. Locations can be found using easting/northing (or x, y) pairs. The coordinates are most commonly associated with the Universal Transverse Mercator coordinate system (UTM), which has unique zones that cover the Earth to provide detailed referencing. However, other units (e.g., survey feet) are also used. When using common projections such as the transverse Mercator projection, these are distances projected on an imaginary surface similar to a bent sheet of paper, and are not the same as distances measured on the curved surface of the Earth.Įasting and northing coordinates are commonly measured in metres from the axes of some horizontal datum. Easting is the eastward-measured distance (or the x-coordinate) and northing is the northward-measured distance (or the y-coordinate). Įasting and northing are geographic Cartesian coordinates for a point.
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