What is ‘dark oxygen’, found 13,000 feet under the sea?

For many years, scientists have proposed ideas about dark matter, a mysterious substance thought to keep galaxies connected through gravity. The mystery of dark matter remains unsolved, and researchers have recently found a new phenomenon they refer to as dark oxygen at the bottom of the ocean.

A new research paper in the scientific journal Nature Geoscience reveals that oxygen is being released from mineral deposits located 4,000 meters below the ocean's surface in the Pacific Ocean's Clarion-Clipperton Zone (CCZ). This depth is roughly equivalent to half the height of Mount Everest, the tallest mountain in the world.

Research conducted by Andrew Sweetman, a professor at the Scottish Association for Marine Science (SAMS) and head of the institution's seafloor ecology and biogeochemistry research team, suggests that there may be an alternative source of oxygen on Earth, aside from the oxygen generated through photosynthesis.

Until this point, scientists have widely known that the Earth's sole provider of oxygen comes from photosynthetic organisms such as plants and algae. These organisms create oxygen that humans and other animals depend on for breathing.

What does this newly discovered dark oxygen mean, and what does it make us wonder about how life first started on our planet?

What Is Dark Oxygen?

In the Clarion-Clipperton Zone (CCZ) in the Pacific Ocean, there are mineral rocks known as polymetallic nodules that resemble coal. These nodules are rich in manganese and iron and have been discovered to generate oxygen without needing photosynthesis. The CCZ covers an area of 4.5 million square kilometres (1.7 million square miles).

Minerals found in the deep sea that create oxygen without any sunlight may challenge scientists' theories about the origin of life on Earth.

"The research could also provide insights into the origins of life on Earth. The findings suggest that there may have been a different source of oxygen in the past, allowing aerobic organisms to exist before the evolution of photosynthesis. This raises the possibility that similar processes could be occurring on other planets as well," Sweetman explained in a SAMS video.

Discovering The Mystery Of Dark Oxygen

The finding was made over a decade following the initial identification of the mysterious dark oxygen. The 2013 expedition was focused on determining the amount of oxygen being used by creatures living on the seafloor of the Clarion-Clipperton Zone.

Landers, which are mechanical platforms that can descend rapidly to the ocean floor, were deployed to a depth of 4,000 meters (13,000 feet) to monitor the decrease in oxygen levels as depth increased.

But what scientists found was that the amount of oxygen at the bottom of the ocean went up.

This news came as a shock to Sweetman and his colleagues. Previously, researchers thought that the oxygen found in the deep sea was derived from the surface ocean and land, created by plants, plankton, and algae through photosynthesis.

This typically means that the further down you go, the less oxygen there is. However, that is not the case here.

Believing that his measurement tools were not accurate, Sweetman had them adjusted and conducted the experiment multiple times over a number of years - each time yielding the identical outcomes.

After conducting numerous experiments over time, they found that manganese nodules were responsible for creating oxygen. They collected these nodules and brought them onto the ship to examine further. They observed that the nodules had an electrical charge, similar to that of an AA battery.

In their lab tests, they saw that seawater electrolysis is a method that can separate seawater into hydrogen and oxygen by using an electric charge.

Why Is The Discovery Important?

In the field of science, information is checked to make sure it's accurate. Other studies will need to be done to confirm these findings.

However, Sweetman and his colleagues' study indicates that certain minerals can generate oxygen without relying on sunlight.

"The introduction of another oxygen source besides photosynthesis on Earth has significant and far-reaching implications," stated Nick Owens, who serves as the director of SAMS.

The researchers who made this discovery are emphasizing the importance of preserving environments that create their own oxygen.

Sweetman explained that in order to support the growth of environmentally friendly industries, we must extract metals from the earth or potentially the deep sea. He emphasized the importance of considering the location of deep ocean mining and the impact it may have on the ecosystem's oxygen production.

Moreover, the potential consequences of finding another deep ocean oxygen source provide an opportunity to reconsider the origins of life on our planet.

Owens stated that having another source of oxygen besides photosynthesis has significant and far-reaching effects.