Antarctic lake home to ancient life

The findings shed light on the extreme limits at which life can live not just on Earth, but possibly alien worlds, scientists added. (DRI)

Located in East Antarctica, Lake Vida lies at an elevation of 350 m, 125 km (79 miles) Northwest of McMurdo Station in the Victoria Valley, which is one of the northernmost of the McMurdo Dry Valleys. (Brad Herried, Lead Cartographer Antarctic Geospatial Information Center)

Members of the 2010 Lake Vida expedition team, Dr. Peter Doran (professor, University of Illinois, Chicago), Dr. Chris Fritsen (research professor, Desert Research Institute, Reno, Nev.) and Jay Kyne (an ice driller) use a sidewinder drill inside a secure, sterile tent on the lakes surface to collect an ice core and brine existing in a voluminous network of channels 16 meters and more below the lake surface. (Desert Research Institute, Emanuele Kuhn)

"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.

Scientists looking for bacteria in the waters of a buried Antarctic lake used a clean room environment to keep the area sterile and avoid introducing contamination. (Alison Murray)

Research field camp on Lake Vida, located in Victoria Valley, the northern most of the McMurdo Dry Valleys. (Desert Research Institute, Alison Murray)

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.