The findings shed light on the extreme limits at which life can live not just on Earth, but possibly alien worlds, scientists added.
"That ice is so thick, nothing from the outside can get down to the water naturally,"researcher Peter Doran, an earth scientist at the University of Illinois at Chicago, said from a research outpost on Antarctica.
The brine ranges from yellow to orange in color due to iron-laced compounds within it. The investigators found the temperature of the water was about 8 degrees Fahrenheit (minus 13 degrees Celsius) — its saltiness, about five to six times greater than average ocean water, keeps it from freezing like freshwater or seawater would. It is also completely depleted of oxygen and mildly acidic.
But despite the tough set of conditions, the researchers found the diverse and thriving community of microbes in the brine. "What's most surprising is that there's anything living down there — it's a pretty harsh environment for life to take hold," Doran told OurAmazingPlanet. "There's a mantra that goes, 'wherever on Earth you find water, you find life,' and this is another one of those examples."
The overall chemistry of this brine suggests that chemical reactions between the water and the underlying sediment generated the reactive chemicals seen in the brine. The molecular hydrogen seen in the brine might serve as a fuel source to help support its microbial life, researchers added.
Beneath the icy surface of a buried Antarctic lake, in super-salty water devoid of light and oxygen that is also cold enough to freeze seawater, researchers have now discovered that a diverse community of bacteria has survived for millennia.