Scientists have discovered Dark Oxygen in the depths of the Pacific Ocean, challenging long-held beliefs about how oxygen is produced on Earth. The Scottish Association for Marine Science (SAMS) is launching a multi-year research program to investigate the phenomenon, supported by a £2 million (approximately €2.7 million) funding package from the Nippon Foundation, the world's largest charitable organization, according to CNN.
Over the past year, a team of scientists specializing in ocean depths uncovered that oxygen can be produced in total darkness on the ocean floor. The finding contradicts the idea that the vital gas can be produced only through photosynthesis. “Our discovery represents a paradigm shift in understanding the marine depths and life on Earth,” said Professor Andrew Sweetman from SAMS, as reported by Newsweek.
The research team, led by Sweetman, plans to deploy specially designed sensors to the ocean's deepest zones to explore the mysteries surrounding Dark Oxygen. These autonomous landers will carry specialized instruments capable of withstanding extreme pressures. “We are already in conversation with experts at NASA who believe that dark oxygen could reshape our understanding of how life might be sustained on other planets without direct sunlight,” Sweetman stated, according to CNN. The discovery has implications for astrobiology, potentially expanding the search for extraterrestrial life on planets where sunlight does not reach.
The phenomenon was discovered in the Clarion-Clipperton Zone, a vast flat area of the ocean floor between Hawaii and Mexico, spanning 1.7 million square miles.
Oxygen production at these depths occurs through naturally occurring polymetallic nodules that act like natural batteries, splitting seawater (H₂O) into hydrogen and oxygen through electrolysis. The process was unexpected because oxygen production was thought to occur exclusively through marine plants via photosynthesis, requiring sunlight.
“The sea is vital for the maintenance of human life and biodiversity, but even today a large part of the deep sea is unknown. We are passionate about innovation for achieving a better society, and we are proud to support Professor Sweetman's research on Dark Oxygen in the hope that we will learn more about the deep sea and the life that exists on the ocean floor,” said Yohei Sasakawa, president of the Nippon Foundation.
“This discovery overturns the traditional understanding of photosynthesis and opens possibilities for understanding life in environments previously thought to be inhospitable, adding an unheard dimension to Earth's biochemical processes,” noted Science.
Professor Nick Owens, Director of SAMS, highlighted the significance of this endeavor. “As an institution, our roots go back to the Challenger expedition of the United Kingdom from 1872–76. It is fitting that 150 years after that mission which gave us our first knowledge of the deep ocean, we are now revealing some of its best-kept secrets,” he said.
The discovery underscores how little is known about the ocean's depths and could reshape our understanding of the conditions of primordial Earth, characterized by environments very different from those today.
This article was written in collaboration with generative AI company Alchemiq