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Geography

The Habitability of Tidally Locked Exoplanets in the Habitable Zone

Quick fact

Many of the most promising exoplanets for life, like TRAPPIST-1e, are tidally locked, meaning they always show the same face to their star. This creates a permanent dayside and nightside, with a narrow 'terminator' ring of twilight between them.

Why this is interesting

Imagine a planet where one side always faces its sun, forever baking, while the other side is trapped in eternal night. Could life survive on such a world?