in geodesy, pairs of numbers that determine the position of points in the plane of a geodetic projection. Grid coordinates are used in the numerical processing of the results of geodetic measurements, in the compilation of topographic maps, and in the practical application of topographic maps and geodetic data.
The Gauss-Krüger projection is used in the USSR and a number of other countries. It is a conformal projection of the terrestrial ellipsoid onto a plane such that the central meridian is represented by a straight line, which is the axis of symmetry of the projection. There are no distortions on the central meridian. Separate zones of the terrestrial ellipsoid that are bounded by two meridians are mapped in the plane of the Gauss-Krüger projection. The central meridian of the zone and the equator are represented by lines in the plane, which taken as the axes of the abscissas and the ordinates, respectively, of the grid coordinates. The abscissas of the points representing the central meridian are equal to the arcs of meridian from the equator to the points; the ordinates of the points are zero.
G. A. MESHCHERIAKOV