Scientists have discovered life in tiny bubbles in so-called flammable ice, providing a “tantalising clue” about the existence of life on other planets.
Researchers made the discovery while studying large underwater rafts of hydrate, known as “flammable ice” or methane hydrate, which forms when ice traps methane within its molecular structure.
They found microhabitats, dubbed “death stars” by the scientists, which are grown by microbes within tiny bubbles of oil and water found in the sheets of frozen gas and ice in the Sea of Japan.
Dr Glen T Snyder, lead author of the study, from Meiji University in Japan, was melting hydrate to study methane gas when he noticed an unusual powder consisting of microscopic spheroids with mysterious dark cores.
Using analytical techniques pioneered at the University of Aberdeen and suited to small sample quantities, Dr Stephen Bowden from its School of Geosciences was able to show that oil was being degraded in the microenvironments within the methane hydrate.
Scientists said that discovering life in such inhospitable conditions offers clues as to the possibility of life on other planets.
Dr Bowden said: “In combination with the other evidence collected by my colleagues, my results showed that even under near-freezing temperatures, at extremely high pressures, with only heavy oil and saltwater for food sources, life was flourishing and leaving its mark.
“It certainly changes how I think about things. Providing they have ice and a little heat, all those frigid cold planets at the edge of every planetary system could host tiny microhabitats with microbes building their own ‘death stars’ and making their own tiny little atmospheres and ecosystems, just as we discovered here.”
The discovery stemmed from a larger project led by Professor Ryo Matsumoto from Meiji University, which was investigating methane hydrate as an energy source that emits less waste carbon than traditional fossil fuels.
Dr Snyder said: “The methane in ‘methane hydrate’ is known to form as microbes degrade organic matter on the seafloor.
“But what we never expected to find was microbes continuing to grow and produce these spheroids, all of the time while isolated in tiny cold dark pockets of saltwater and oil.
“It certainly gives a positive spin to cold dark places, and opens up a tantalising clue as to the existence of life on other planets.”
The discovery of the microhabitats is revealed in a paper published in the journal Scientific Reports, a Nature publication.