The Best Neighborhoods for Starting a Life in the Galaxy

To harbor life, at least as we know it, a planet must orbit a star that is relatively calm and stable. The planet’s orbit must also be nearly circular so the planet experiences similar warmth throughout its year. And it must be not too hot, lest any surface water boil off; not too cold, lest that water remain locked in ice; but just right, so that rivers and seas remain liquid.

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