Question

what we think about prime meriediam

Answer 1

A prime meridian is a meridian (a line oflongitude) in a geographic coordinate systemat which longitude is defined to be 0°. Together, a prime meridian and its antimeridian (the 180th meridian in a 360°-system) form a great circle. This great circle divides the sphere, e.g., Earth, into twohemispheres. If one uses directions of East and West from a defined prime meridian, then they can be called the Eastern Hemisphereand the Western Hemisphere.