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Earth is the solar system's third planet, counting from the center outward, and its orbital radius is approximately 93 million miles, or 150 million kilometers. Although Earth is the only body in the Solar System which is currently known to possess life, it is worth noting that our knowledge of other worlds is too limited to rule out the possibility of life having ever existed elsewhere than Earth.
Earth is approximately 4.5 billion years old, and life has existed on it for roughly 4 billion years.

The science concerned with Earth is geology.