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Researchers found that some Pacific Ocean rocks can produce oxygen, called ‘dark oxygen’, without sunlight, challenging the idea that oxygen generation only relies on photosynthesis

Dark oxygen is not derived from plants but comes from polymetallic nodules that resemble coal piles in the depths of the Pacific Ocean. (News18 Hindi)
The scientific landscape is always changing, with fresh discoveries emerging daily. The ocean, in particular, is filled with secrets that researchers are indefatigably working to uncover. Nature possesses endless marvels that continually inspire awe. Recently, a revelation from the ocean’s depths has surprised even experienced scientists: specific rocks are showcasing an astonishing occurrence.
Researchers have discovered that certain rocks, found in the shadowy depths of the Pacific Ocean, can produce oxygen without relying on sunlight, a phenomenon now referred to as ‘dark oxygen’. This finding contradicts previously established scientific principles as until now, it was generally believed that oxygen generation solely emerged from photosynthesis, which requires the presence of sunlight.
What is Dark Oxygen?
Dark oxygen denotes oxygen that is produced in the deep ocean without sunlight. It arises from the interaction between rare metal deposits on the ocean floor and saltwater. This oxygen generation happens through a variety of abiotic and biological mechanisms, potentially supporting aerobic life in dark, oxygen-sparse regions.
Why Does This Discovery Matter?
It was previously thought that oxygen resulted exclusively from photosynthesis, a process that depends on sunlight. Marine plankton (Haloplankton), floating plants, algae, and specific bacteria are the main sources of oxygen in the ocean, all of which depend on photosynthetic processes.
The production of oxygen at such ocean depths was deemed impossible due to the absence of sunlight required for photosynthesis. Nevertheless, in this case, the oxygen is not derived from plants. Instead, it comes from polymetallic nodules that resemble coal piles. These nodules, made up of metals such as manganese, iron, cobalt, nickel, copper, and lithium, can produce oxygen through electrochemical reactions even when light is not present.
In essence, these nodules facilitate the splitting of H2O molecules into hydrogen and oxygen. Thus, the discovery of ‘dark oxygen’ is essential to understanding an oxygen-related phenomenon or environment in the depth of the ocean bereft of light.