From HomoExcelsior

The idea that around other stars are planets just like this one -- blue sky, clouds, mountains, forests, oceans, animals. Another Gaia, rare precious jewel of the stellar wilderness, with only a handful in our vast Galaxy. Venus typifies most terrestrial planets -- heavy atmosphere and slow rotation about a tumbling axis. Only the one-in-a-million cosmic bank shot of a Giant Impact will produce a Moon-stabilized planet. Further rare events, outlined in the Slushball Earth scenario, are required to stimulate the evolution of eukaryotic cells and later the origin of multicellular life. Finally, asteroidal impacts every few hundred million years (not hundred thousand) seem necessary to stir the evolutionary pot. The recent book 'Rare Earth'articulates this meme, for which I propose the label 'EarthWorld'.

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