Planet earth is certainly not the biggest or hottest or coldest planet. But earth is the most unique planet in the entire solar system simply because it supports life. Earth is the only green planet of the solar system, with photosynthetic plants and liquid water and soil for sustaining all forms of life. This planet is remarkable due to the presence of free oxygen that is essential for any living organism.
In terms of physical proportions, earth is the fifth largest among the planets. The earth’s brown crust is only the top layer of a set of layers, ending at the hottest inner core. Planet earth is covered by water, about seventy percent. The polar ice caps and oceans form a majority of the water resource on earth. 77 percent of this planet’s atmosphere is the compound nitrogen; with the rest of the gases being the most important oxygen (21%) followed by the carbon-dioxide and other gases up to the rare and light gases in smaller proportions.
The moon is the only natural satellite of the earth, orbiting constantly around the planet. Earth is the third planet in terms of distance from the sun. Among the terrestrial planets, Earth is the biggest.
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