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Earth's Oceans May Have Been Green, Study Reveals

4/13/2025

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Summary

Story summary

Japanese researchers have unveiled a groundbreaking theory: Earth's ancient oceans may have been green rather than blue, thanks to elevated iron levels and the rise of cyanobacteria. Their study in Nature reveals that green light played a crucial role in early photosynthesis, potentially transforming our perspective on life beyond Earth, where green oceans could hint at microbial existence.

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Story summary

Japanese researchers have unveiled a groundbreaking theory: Earth's ancient oceans may have been green rather than blue, thanks to elevated iron levels and the rise of cyanobacteria. Their study in Nature reveals that green light played a crucial role in early photosynthesis, potentially transforming our perspective on life beyond Earth, where green oceans could hint at microbial existence.