In the deep-sea trenches near the Kamchatka coast, where sunlight does not penetrate, organisms have been discovered that chose chemosynthesis as an alternative to photosynthesis. The finding has already been hailed as one of the most significant of 2025, and the paper’s authors themselves state that the next stage is a search for similar life forms on other planets.
Life in the “Underworld”
Scientists from the P. P. Shirshov Institute of Oceanology of the Russian Academy of Sciences, as part of an international team, surveyed 2.5 thousand kilometers of the Kuril-Kamchatka and Aleutian trenches. The Chinese manned submersible “Fendouzhe” descended to the seabed at depths ranging from 5800 to 9533 meters. Such a zone is called the ultra-abyss, or hadal, from the Greek word “Hades”—the realm of the dead. For comparison: the “Titanic” rests at a depth of 3800 meters.
“This is a unique natural laboratory for studying the conditions under which life could have originated on our planet: organisms survive in complete darkness, in water with a temperature close to freezing, and under pressure almost 1000 times greater than on the Earth’s surface,” explains the Russian Science Foundation, which financed the research.
One of the most prevalent species turned out to be Siboglinid polychaetes—marine bristle worms. Their main characteristic is the absence of a familiar digestive system: no mouth, no intestine, no anus. These creatures subsist through symbiosis with bacteria inhabiting them internally. Siboglinids absorb chemicals from the environment—in this instance, hydrogen sulfide and methane—and transport them to the bacteria via their circulatory system. The bacteria, using chemosynthesis—energy derived from hydrocarbon oxidation—produce organic matter (sugars and proteins).
Colonies of Siboglinid polychaetes (a-c) and bivalve mollusks (d) on the seabed | © CC BY-NC-ND 4.0/Peng, X., Du, M., Gebruk, A. et al./Representative fauna of cold-seep sites in the Kuril–Kamchatka Trench and western Aleutian Trench (cropped)
The communities of living organisms in this Far Eastern “underworld” proved unexpectedly diverse, and the population density was extremely high: up to 5800 worms and nearly 300 mollusks per square meter. Scientists identified several large “fields.” Each is dominated by different species, and alongside them reside numerous other animals: snails, sea lilies, holothurians, and amphipods, which likely feed on the abundance of the chemical ecosystem.
The expedition took place in 2024. The research results were published in the prestigious journal Nature in the summer of 2025. In December, the work was listed among the ten most important discoveries made by Russian scientists in 2025, according to the Russian Science Foundation and RIA “Russia Today.”
Now—to other planets
“We have known about life based on chemosynthesis for a long time. One component of our finding is that it is possible in ocean depths approaching the maximum. This expands the limits of our understanding of life’s potential,” explains Andrey Gebruk, Deputy Director of the Institute of Oceanology for the direction “Ecology of Seas and Oceans” and one of the study’s authors, to RIA Novosti.
According to him, the search will not be restricted to Earth’s oceans.
“The next inevitable step is to seek such life forms on other celestial bodies: planets, moons, and so on,” the scientist states.
Gebruk reminds us that science learned about organisms based on chemosynthesis half a century ago. This spurred a new field—astrobiology. The discovery by Russian scientists once again demonstrated that even the harshest conditions—temperatures near zero and ultra-high pressure—should not deter those searching for extraterrestrial life.
“We found methane seeps on the floor of the Kuril-Kamchatka Trench, but not as violently bubbling gas—no, it seeps slowly, imperceptibly from the bottom, yet in a gigantic volume. Methane, however, is not only fuel for deep-sea life. It is a climatically active gas, potential reserves of gas hydrates, and a possible future energy resource,” the scientist enumerates.
According to the oceanologist, the discovery of methane on such a scale means that global models of carbon fluxes in the ocean and their influence on the climate will now require serious revision and new calculations.
“Kamchatka” life beyond Earth
In the opinion of some scientists, chemosynthesis is a much more probable foundation for extraterrestrial life than photosynthesis, as it does not rely on sunlight and can exist on the internal energy of the celestial body. Moreover, most other planets and moons that might host alien organisms are significantly farther from the Sun than Earth.
Recent work by scientists from Rutgers University showed that chemotrophs could exist on Jupiter’s moon, Europa. Beneath its thick ice crust lies a salty ocean, and processes like serpentinization and tidal heating could create hydrothermal vents on the floor—an ideal environment for chemosynthetic microbes analogous to Earth’s. According to the paper’s authors, the same principle applies to Enceladus—a moon of Saturn, also covered by a subsurface ocean of water.
First images of the moon Europa, transmitted to Earth from the “Juno” space probe, September 29, 2022 | © NASA / JPL-Caltech, SWRI, MSSS
Another candidate is Mars. Researchers from Brown University (USA) proposed a theory in 2018 that the Red Planet likely possessed sufficient chemical energy in ancient times for microbes to flourish underground.
Finally, life is also considered possible on Titan—Saturn’s largest moon. It is the only celestial body in the Solar System besides Earth covered in oceans. True, these are not made of water but of hydrocarbons, mainly the same methane, and Titan’s surface temperature is minus 179 °C. If life arose under these conditions, it would differ greatly from Earth-based forms, including chemosynthetic ones. However, organisms similar to those found near Kamchatka could hypothetically exist beneath the moon’s surface.
In any case, this is no reason to abandon the search for life—as the discovery by Russian scientists showed, it can exist even where no one expected to see it.
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