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A globe is a three-dimensional, spherical, scale model of Earth (terrestrial globe or geographical globe) or other celestial body such as a planet or moon. While models can be made of objects with arbitrary or irregular shapes, the term ''globe'' is used only for models of objects that are approximately spherical. The word “globe” comes from the Latin word ''globus'', meaning round mass or sphere. Some terrestrial globes include relief to show mountains and other features on the Earth’s surface. There are also globes, called celestial globes or astronomical globes, which are spherical representations of the celestial sphere, showing the apparent positions of the stars and constellations in the sky. ==Terrestrial and planetary== Flat maps are created using a map projection that inevitably introduces an increasing amount of distortion the larger the area that the map shows. A globe is the only representation of the Earth that does not distort either the shape or the size of large features – land masses, bodies of water, etc. The circumference of the Earth is almost exactly 40 million metres.〔The Earth’s circumference is (almost) exactly 40,000 km because the original definition of the metre was based precisely on this measurement – more specifically, 1/10-millionth of the distance between the poles and the equator.〕〔Arc length#Arcs of great circles on the Earth〕 Many globes are made with a circumference of one metre, so they are scale models of the Earth with a scale of one to 40 million. A distance of one centimetre on the globe represents 400 kilometres on the Earth. One inch represents about 630 miles. Some globes are made with a diameter of one foot. These are about four percent smaller than the metre-circumference globes, so their scales are correspondingly different. One centimetre (inch, etc.) on a foot-diameter globe represents an approximately 4% ''larger'' distance on the Earth than does the same distance on a metre-circumference globe. Globes of various other sizes are also sometimes found. Sometimes a globe has surface texture showing topography; in these, elevations are exaggerated, otherwise they would be hardly visible. Most modern globes are also imprinted with parallels and meridians, so that one can tell the approximate coordinates of a specific place. Globes may also show the boundaries of countries and their names, a feature that can quickly become out of date, as countries change their name or borders. Many terrestrial globes have one celestial feature marked on them: a diagram called the analemma, which shows the apparent motion of the Sun in the sky during a year. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「globe」の詳細全文を読む スポンサード リンク
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