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Our Home Planet
Earth, our home planet, is the only planet in our solar system known to harbor life - life that is incredibly diverse. All the things we need to survive exist under a thin layer of atmosphere that separates us from the cold, airless void of space.

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young

When used to describe a planetary surface "young" means that the visible features are of relatively recent origin, i.e. that older features have been destroyed (e.g. by erosion or lava flows). Young surfaces exhibit few impact craters and are typically varied and complex. In contrast an "old" surface is one that has changed relatively little over geologic time. The surfaces of Earth and Io are young; the surfaces of Mercury and Callisto are old.

 
Can't find it? Don't understand it? Ask us.
Q
young

When used to describe a planetary surface "young" means that the visible features are of relatively recent origin, i.e. that older features have been destroyed (e.g. by erosion or lava flows). Young surfaces exhibit few impact craters and are typically varied and complex. In contrast an "old" surface is one that has changed relatively little over geologic time. The surfaces of Earth and Io are young; the surfaces of Mercury and Callisto are old.