9781422283691

Int roduct ion T

he Earth is our home in space. Alien space travelers visiting our Solar System would see that Earth is quite different

from the other planets. From a distance, they would see the Earth as a mainly blue sphere, flecked with white and brown, floating in the inky blackness of space . . . beautiful place. Moving closer, our alien visitors would find that the blueness of our planet is the vast oceans. The white patches are clouds, and the brown ones are land.

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