Scientists plan deep-sea expedition to probe ‘dark oxygen’

A team of scientists announced on Tuesday that they had developed new deep-sea landers specifically to test their contentious discovery that metallic rocks at the bottom of the ocean are producing “dark oxygen”.

If a previously unknown source of oxygen has always been lurking in Earth’s depths, it would represent a remarkable revelation that would call into question long-held assumptions about the origins of life on our planet.

But the deep-sea mining industry – which is keen to extract precious metals from these potato-sized polymetallic nodules – and some researchers have expressed doubts about the claim.

So British marine ecologist Andrew Sweetman, who led the 2024 research that revealed the possible existence of dark oxygen, is planning a new underwater expedition in the coming months.

At a press conference on Tuesday, Sweetman and his team unveiled two new landers capable of diving to a depth of 11km (seven miles) with the aim of finding out how the nodules could be creating oxygen.

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Life finds a way in the deepest ocean trenches

Life finds a way in the deepest ocean trenches

Unlike previous missions, these landers will have sensors specifically designed to “measure sea floor respiration”, Sweetman explained.