Over the past several decades, scientific ocean drilling has significantly expanded our knowledge of life and Earth. The discovery of deep microbial life and its ecosystems beneath the ocean floor suggests that subseafloor microbial ecosystems may have uniquely co-evolved in association with Earth dynamics, and this inevitable interrelationship has shaped planetary habitability for more than 3 billion years. In the future, scientific ocean drilling—from the surface to drilling’s accessible limit in the upper mantle—will permit a better understanding of what is life, why we are here, and what are the possible trajectories of our planet’s habitability and its sustainability as well as that of other celestial bodies in the universe.

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