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Earth, the planet in the solar system known to life, is a beautiful planet composed 70% of salt water and 30% land and fresh water on its surface. From space, the oceans give it a bluish color, land regions look brown, and cloud looks white. Earth features a of landforms and landscapes, all of which are to some forms of life. Over two million different forms of life have been on planet Earth to this day, but believe there are millions more that have to be identified. Planet Earth, like Mercury and Venus, features mountain ranges, canyons, ridges, plains, and of volcanic activity. Unlike the aforementioned terrestrial planets, Earth features numerous water sources - the ultimate to life. The total of all of the water on Earth (to a depth of 2,000 meters) is known as its hydrosphere.