Some references note that Asia lies primarily in the Eastern and Northern Hemispheres. But the word “primarily” is important since there are two Asian countries have territory in the Southern Hemisphere. A substantial part of Indonesia lies south of the equator and all of Timor Leste is south of the equator. Therefore, Asia has territory in at least three hemispheres: Northern, Southern and Eastern.

What about the Western Hemisphere? If we consider the prime meridian (0 degrees longitude) running through the UK, France, Spain and several African countries from Algeria to Ghana it is clear that no part of Asia lies anywhere between that meridian and the Americas.

But consider the antimeridian (180 degrees longitude), that passes right through the Pacific Ocean: go west of the antimeridian and you are in the Eastern Hemisphere; go east of it and you are in the Western Hemisphere. The northern end of the antimeridian passes through Chukotka Autonomous Okrug, in the extreme far eastern part of Russia. That part of Russia is clearly in Asia, but it lies on both the eastern and the western side of the 180-degree line of longitude. Therefore, part of the territory of Asia also lies in the Western Hemisphere.

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