A fascinating discovery in the darkest depths of the ocean has led researchers to uncover a process that might allow oxygen to be generated without sunlight. This breakthrough, made by placing sensors on the seafloor at depths of approximately 5 km between Hawaii and Mexico, challenges the long-standing belief that oxygen production occurs solely through photosynthesis.

The sensors recorded rising oxygen levels, which researchers believe is the result of metal nodules on the seafloor generating electric currents capable of splitting seawater into oxygen and hydrogen. This unexpected discovery could have wide-reaching implications for life in extreme environments, both on Earth and potentially on other planets or moons.

Prof Andrew Sweetman, the lead researcher from the Scottish Association for Marine Science, shared the findings with BBC News and explained the process further. The discovery has caught the attention of NASA, who are exploring the potential for this oxygen generation process to support microbial life in environments once thought to be inhospitable. Prof Sweetman highlighted that understanding how oxygen can be produced in such conditions may transform the way scientists search for life beyond Earth.

The discovery has also led to renewed debates about the environmental impact of deep-sea mining, particularly with respect to metal nodules. Critics, including marine scientists and environmental organizations, have raised concerns that mining operations could harm delicate marine ecosystems. Over 900 scientists have signed a petition calling for a pause in deep-sea mining activities until more is understood about these ecosystems.

In response to these concerns, Prof Sweetman stated that further experiments would help clarify the implications of deep-sea mining and ensure a responsible approach to future industrial activities. He stressed the importance of cautious exploration before committing to large-scale seabed mining.