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24/04/2025
4,000 meters below the surface of the Pacific Ocean, scientists have made a discovery that could reshape what we know about life on Earth—and even life beyond it.
In the Clarion-Clipperton Zone, researchers found that polymetallic nodules—metal-rich rocks spread across the seafloor—may be creating oxygen in complete darkness. Acting like tiny natural batteries, these nodules split seawater into hydrogen and oxygen through electrochemical reactions, without sunlight or microbes.
This process, now called “dark oxygen,” challenges the long-standing idea that oxygen can only be produced through photosynthesis. It could offer clues about how life began on Earth—and how it might exist on other planets.
But the discovery also comes with a warning. These nodules are the target of deep-sea mining efforts for metals like cobalt and nickel, used in electric vehicle batteries and clean energy tech. If mining disrupts this ecosystem, we could destroy one of Earth’s most mysterious oxygen sources before we even understand it.
