Goldilocks Zone Moves Outward

The "Goldilocks Zone" is not a fixed ring in space. NASA defines it as the distance from a star where liquid water could exist on a planet’s surface, and that distance depends on the star’s size and brightness, not on a permanent cosmic boundary. As stars change over time, the habitable zone shifts too, which means frozen worlds can warm enough for liquid water while planets that once sat in more Earth-like conditions can eventually become too hot and dry.

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