A team of scientists announced on Tuesday that they have developed new deep-sea landers specifically to test their contentious discovery that metallic rocks at the bottom of the ocean are producing “dark oxygen”.<\/p>\n
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.<\/p>\n
But the deep-sea mining industry \u2014 which is keen to extract precious metals from these potato-sized polymetallic nodules \u2014 and some researchers have expressed doubts about the claim.<\/p>\n
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.<\/p>\n
At a press conference on Tuesday, Sweetman and his team unveiled two new landers capable of diving to a depth of 11 kilometres (seven miles) with the aim of finding out how the nodules could be creating oxygen.<\/p>\n
Unlike previous missions, these landers will have sensors specifically designed to “measure seafloor respiration”, Sweetman explained.<\/p>\n
They can withstand 1,200 times the pressure on Earth’s surface and more resemble space exploration equipment, a statement said.<\/p>\n
The landers will be launched from a research ship in the Clarion-Clipperton Zone, a vast region between Hawaii and Mexico.<\/p>\n
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Mining companies have plans to start harvesting the nodules, which contain valuable metals used in electric car batteries and other tech.<\/p>\n
The scientists believe that the nodules give off enough electric charge to split seawater into hydrogen and oxygen, a process known as electrolysis.<\/p>\n
Underwater gold rush?<\/span><\/h2>\nSweetman also used the press conference to push back against criticism of his 2024 study.<\/p>\n
Some researchers have suggested that the oxygen was not coming from the nodules, but instead were just air bubbles trapped in the measuring instruments.<\/p>\n
“We’ve used these instruments over the last 20 years and every time we’ve deployed them, we’ve never had bubbles,” Sweetman said, adding that the team conducted tests to rule out such a possibility.<\/p>\n
The debate comes as companies and nations battle over proposed rules regulating the new and potentially environmentally destructive deep-sea mining industry.<\/p>\n
Sweetman’s 2024 study was partly funded by a Canadian deep-sea mining firm, The Metals Company, which has since sharply criticised his research.<\/p>\n
“If commercial mining goes ahead then there will be quite widespread impacts,” Sweetman said, adding that “these nodules are home to a variety of diverse fauna”.<\/p>\n
But the scientist emphasised it is “not our intention” to find something to stop deep-sea mining.<\/p>\n
He instead wants to gather as much information as possible to “minimise the impacts as much as possible” if mining does go ahead.<\/p>\n
Matthias Haeckel, a biogeochemist at Germany’s GEOMAR Helmholtz Centre for Ocean Research, told AFP<\/span> that his own research did “not show any hint towards oxygen production” from the nodules.<\/p>\nBut he said Sweetman will “join our cruise at the end of this year, where we plan to compare our methods”.<\/p>\n
For the new research funded by the Japanese Nippon Foundation, Sweetman and his team plan to spend May on a research ship in the Clarion-Clipperton Zone.<\/p>\n
“We’ll be able to confirm dark oxygen production within 24 to 48 hours after the landers come up,” he said.<\/p>\n
The world will probably not know the results until the ship returns in June \u2014 and further experiments back on dry land could take months, Sweetman added.<\/p>\n<\/p><\/div>\n
But he said Sweetman will “join our cruise at the end of this year, where we plan to compare our methods”.<\/p>\n
For the new research funded by the Japanese Nippon Foundation, Sweetman and his team plan to spend May on a research ship in the Clarion-Clipperton Zone.<\/p>\n
“We’ll be able to confirm dark oxygen production within 24 to 48 hours after the landers come up,” he said.<\/p>\n
The world will probably not know the results until the ship returns in June \u2014 and further experiments back on dry land could take months, Sweetman added.<\/p>\n<\/p><\/div>\n