I see many references to 'The Western Hemisphere.' The boundary between the northern and southern hemispheres is clear, the equator. Is there an accepted definition of the boundary of the Eastern and Western hemispheres, eg a line of latitude, or is it just a matter of opinion?

jdtf01

The Prime Meridian is the meridian (line of longitude) at which longitude is defined to be 0°. The Prime Meridian and the opposite 180th meridian (at 180° longitude), which the International Date Line generally follows, form a great circle that divides the Earth into the Eastern and Western Hemispheres. Unlike the parallels of latitude, which are defined by the rotational axis of the Earth (the poles being 90° and the Equator 0°), the Prime Meridian is arbitrary. By international convention, the modern Prime Meridian is one passing through Greenwich, London, United Kingdom, known as the International Meridian or Greenwich Meridian. Historically, various meridians have been used, including four different ones through Greenwich. Oct 02 08, 1:01 AM

looney_tunes

Technically, the Western hemisphere lies west of the Prime Meridian and extends to the 180th meridian. It is also sometimes used to refer to North and South America, which comprise the bulk of the hemisphere. And, as a political reference, it may be extended to include the rest of Europe (most of which is in the geographical Eastern hemisphere) and Australia. http://en.wikipedia.org/wiki/Western_hemisphere Oct 02 08, 1:12 AM

jdtf01

The Prime Meridian is the meridian (line of longitude) at which longitude is defined to be 0°. The Prime Meridian and the opposite 180th meridian (at 180° longitude), which the International Date Line generally follows, form a great circle that divides the Earth into the Eastern and Western Hemispheres. Unlike the parallels of latitude, which are defined by the rotational axis of the Earth (the poles being 90° and the Equator 0°), the Prime Meridian is arbitrary. By international convention, the modern Prime Meridian is one passing through Greenwich, London, United Kingdom, known as the International Meridian or Greenwich Meridian. Historically, various meridians have been used, including four different ones through Greenwich. http://en.wikipedia.org/wiki/Prime_Meridian Oct 02 08, 1:28 AM