Event or Process

Longitude and Latitude

Latitude and longitude form a geographical coordinate system used for locating places on the surface of the earth. They are angular measurements, expressed as degrees of a circle measured from the center of the earth. The earth spins on it axis, which intersects the surface at the north and south poles. The poles are the natural starting place for the graticule, a spherical grid of latitude and longitude lines.

Halfway between the poles lies the equator. Latitude is the angular measurement of a place expressed in degrees north or south of the equator. Latitude runs from 0 degrees at the equator to 90 degrees north or 90 degrees south at the poles. Lines of latitude run in an east-west direction. They are called parallels because they are equally distant from,

Lines of longitude , called meridians, run in a north-south direction from pole to pole. Longitude is the angular measurements of a place east or west of the prime meridian. This meridian is also known as the Greenwich Meridian because it runs through the original site of the Royal Observatory, which was located at Greenwich, just outside London, England. Longitude runs from 0 degrees at the prime meridian to 180 degrees east or west, halfway around the globe. The International Date Line follows the 180 degree meridian, making a few jogs to avoid cutting through land areas.