Earth
It is almost spherical, flattened slightly at the poles, and is composed of five concentric layers: inner core, outer core, mantle, crust, and atmosphere. About 70% of the surface, including the north and south polar ice caps, is covered with water. The Earth is surrounded by a life-supporting atmosphere and is the only planet on which life is known to exist. Earth is the third planet from the Sun, and the fifth largest of the eight planets in the solar system. It is also the largest, most massive, and densest of the solar system's four terrestrial planets. It is sometimes referred to as the World, the Blue Planet or Terra. Earth has approximately 6,803, 000, 000 human inhabitants as of December 12, 2009. Projections indicate that the world's human population will reach seven billion in 2013 and 9.2 billion in 2050. Human population density varies widely around the world. It is estimated that the only one eighth of the surface of the Earth is suitable for humans to live on - three quarters is covered by oceans, and half of the land area is either desert, high mountains or other less suitable terrain.
Independent sovereign nations claim the planet's entire land surface, with the exception of some parts of Antarctica. As of 2007 there are 201 sovereign states. In addition, there are 59 independent territories and a number of autonomous areas, territories under dispute and other entities. Historically, Earth has never had a sovereign government with authority over the entire globe, although a number of nation states have striven for world domination and failed.
Unlike the other planets in the solar system, Earth does not take its name from an ancient Greek or Roman god. The name "Earth" was derived from the Anglo-Saxon word erda, which means ground or soil. It became eorthe in Old English, then erthe in middle English. Earth has often been personified as a deity, in particular a goddess. In many cultures the mother goddess, also called the Mother Earth, is also portrayed as a fertility deity.
My name is Lance Sputnik, and this is my playground.
Sunday, January 10, 2010
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