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THE SUN, EARTH, AND MOON

The question whether the nebular hypothesis is to be accepted as a proved result of science is one on which opinions differ. There are many facts which support it—such as the interior heat of the earth and the revolution and rotation of the planets all in the same direction. But cautious and conservative minds will want some further proof of the theory before they regard it as absolutely established. Even if we accept it, we still have open the question: How did the nebula itself originate, and how did it begin to contract? This brings us to the boundary where science can propound a question but cannot answer it.

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