Latitude ( or ). It is measured in degrees, minutes and seconds or decimal degrees, north or south of the equator. The precise measurement of latitude requires an understanding of the gravitational field of the Earth, either to set up theodolites or to determine GPS satellite orbits. The study of the figure of the Earth together with its gravitational field is the science of geodesy. This article relates to coordinate systems for the Earth: it may be extended to cover the Moon, planets and other celestial objects by a simple change of nomenclature. The graticule is formed by the lines of
Extreme points of Earth land. The pairs of cities (with a population over 100,000) with the greatest distance between them are: These are the longest straight lines that can be drawn between any two points on the surface of the Earth and remain exclusively over land or water; the points need not lie on the same latitude or longitude. Extreme points of Earth This is a list of extreme points of Earth, the geographical locations that are farther north or south than, higher or lower in elevation than, or farthest inland or out to sea from, any other locations on the landmasses, continents or