GSFC_180707_687
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WHAT MAKES A PLANET 'HABITABLE'?

HABITABLE ZONES: The Solar System's habitable zone stretches from near Venus to slightly beyond Mars (top). The habitable zone of a smaller, cooler star like Gliese 581 is closer to the star (middle)

The habitable zone is the "Goldilocks region" around a star, where the surface of an Earth-like planet receives the amount of light needed to bring its temperature into the range where water is liquid (0 to 100 °C).
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