WHAT ARE LATITUDE AND LONGITUDE?

Every place on Earth’s surface can be pinpointed by two figures: its latitude and its longitude. Lines of latitude (called ‘parallels’) form rings around Earth, parallel to the equator. A place’s latitude is given in degrees (°) north or south of the equator, which is considered latitude 0°. On the other hand, lines of longitude (called ‘meridians’) run round Earth from north to south, dividing the world up like the segments of an orange.

A place’s longitude is given as degrees west or east of the prime meridian, which is longitude 0°. 

Latitude and longitude are angles that uniquely define points on a sphere. Together, the angles comprise a coordinate scheme that can locate or identify geographic positions on the surfaces of planets such as the earth.

Latitude is defined with respect to an equatorial reference plane. This plane passes through the center C of the sphere, and also contains the great circle representing the equator. The latitude of a point P on the surface is defined as the angle that a straight line, passing through both P and C, subtends with respect to the equatorial plane. If P is above the reference plane, the latitude is positive (or northerly); if P is below the reference plane, the latitude is negative (or southerly). Latitude angles can range up to +90 degrees (or 90 degrees north), and down to -90 degrees (or 90 degrees south). Latitudes of +90 and -90 degrees correspond to the north and south geographic poles on the earth, respectively.

Longitude is defined in terms of meridians, which are half-circles running from pole to pole. A reference meridian, called the prime meridian , is selected, and this forms the reference by which longitudes are defined. On the earth, the prime meridian passes through Greenwich, England; for this reason it is also called the Greenwich meridian. The longitude of a point P on the surface is defined as the angle that the plane containing the meridian passing through P subtends with respect to the plane containing the prime meridian. If P is to the east of the prime meridian, the longitude is positive; if P is to the west of the prime meridian, the longitude is negative. Longitude angles can range up to +180 degrees (180 degrees east), and down to -180 degrees (180 degrees west). The +180 and -180 degree longitude meridians coincide directly opposite the prime meridian.

Credit: WhatIs.com

Picture credit: Google

Leave a Reply

Your email address will not be published. Required fields are marked *