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Earth (Mythology) Mother Earth: The origin of all life that we know
Earth Seen from the moon as a fragile blue gem so perfect with life so precious to men who lust for your treasures pollutes your wind like addicted rapists drugged and freaked out shooting for change. carlyle miller
EARTH The Earth is a PLANET, a celestial body that revolves around a central star. It is one of the nine known planets revolving around its star, called the Sun (see EARTH, MOTIONS OF), along with a multitude of smaller objects. The system as a whole is known as the SOLAR SYSTEM. Among the planets, the Earth is third in order of increasing distance from the Sun. The Earth-Sun distance, about 149,600,000 km (92,956,000 mi) on the average, is used as a unit of measure by astronomers and is known as the ASTRONOMICAL UNIT. Like all celestial objects, the Earth has a gravitational field (see EARTH, GRAVITATIONAL FIELD OF), and like most other planets it also displays a magnetic field (see EARTH, GEOMAGNETIC FIELD OF). The Earth is accompanied by an orbiting companion, the MOON, than is smaller than the Earth but is large enough for many astronomers to consider the Earth and Moon as a double-planet system. The Earth's own diameter at its equator is about 12,800 km (7,900 mi; see EARTH, SIZE AND SHAPE OF). This makes it only fifth in order of size among the planets. It is the largest of the inner planets, however, which all resemble each other to some degree in structure and composition (see EARTH, STRUCTURE AND COMPOSITION OF). By studying the materials of which the Earth is made, scientists have been able to trace its history through GEOLOGIC TIME (see also EARTH, GEOLOGICAL HISTORY OF). The many fields of scientific pursuit that make up such studies are known collectively as the EARTH SCIENCES. Seen from space, planet Earth appears as a blue ocean sphere that is marked by areas of brown and green, the continents, and white areas of ice at the poles. Flecks and changing masses of clouds drift across this visible surface of sea, land, and ice. The earth is an object of great beauty. Of all the planets and other objects in the universe, it is also the only place known that harbors LIFE. Scientists are seeking signs of life elsewhere in the universe (see LIFE, EXTRATERRESTRIAL), but it seems likely that our planet will remain the only place where human beings or any other of Earth's organisms can live without artificial support for any foreseeable future. Growing concern has been expressed by many scientists, however, for the continuing safety of the planet as a home for life (see POLLUTION, ENVIRONMENTAL). The Earth and its organisms as a whole form a BIOSPHERE that is threatened increasingly by human activities, and it is to this problem that such scientists and other workers are now addressing their efforts.
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