In the geographical coordinate system, the location of the projection of a point on a level surface is determined by two coordinates - angles: latitude and longitude. The latitude of a point is the angle formed by a vertical line at a given point and the plane of the equator. Geographical coordinate system. In the geographical coordinate system, the origin is the center of the Earth, taken as a ball, and the coordinate planes are the plane of the earth's equator and the plane of the zero (initial) meridian.