Hemispheres The globe is divided by convention into four half spheres, using the Greenwich meridian or the Equator as a reference point. The geographical hemispheres of Earth are the cartological divisions of its surface. The most common are the Northern and Southern Hemispheres (separated by the equator) and the Eastern and Western Hemispheres (defined by the arbitrary E and W longitude designations).
A hemisphere is one half of a sphere, so any sphere canbe divided equally in two by a plane through its center.The geographical hemispheres of Earth are thecartological divisions of its surface. The most common are theNorthern and Southern Hemispheres (separated by the equator) andthe Eastern and Western Hemispheres (defined by the arbitrary E andW longitude designations). Locations up to 180° west of theGreenwich or Prime Meridian are the Western Hemisphere. Locationsup to 180° east are in the Eastern Hemisphere.Continents entirely in the Western Hemisphere are North andSouth America. Continents entirely in the Eastern Hemisphere areAsia and Australia. Most of Africa, most of Europe, and half ofAntarctica are also in the Eastern Hemisphere.The only continents that lie entirely in the Southern Hemisphereare Australia and Antarctica.