Rare Earth Background Information

The Rare Earth hypothesis suggests that Earth-like planets containing complex life as we know it are likely quite rare in the Universe. This lesson will explore several parameters that have led the scientists Peter Ward and Donald Brownlee to put forth this hypothesis in their book, Rare Earth: Why Complex Life is Uncommon in the Universe. You may wish to refer to this book for a more detailed description of the Rare Earth hypothesis. You may also find it useful to check out the following websites:

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