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Earth is the third planet from the sun in our solar system. Because of the presence of liquid water and protective atmosphere our home earth can produce life.  It is the fifth largest planet in our solar system.

Earth is known as the "blue planet" because over 71 percent of its surface is covered with water.  Around three-fourths of the Earth's surface is made up of oceans and water bodies that constitute over 70 per cent of the Earth. Its blue appearance from the space comes from the abundant water present on the earth.

This water bodies absorbs the light from the Sun and reflects it. After reflecting the white light from the Sun the color of the light changes to blue. Thus, the Earth appears blue from space.
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