"It's a very exciting result: the first indication of a briny aquifer on Mars", says geophysicist David Stillman of Southwest Research Institute in Boulder, Colorado, who was not a part of the study.The findings, if confirmed, would mark the detection of the largest body of liquid water on Mars today reports Marina Koren in The Atlantic.
The lake is about 12 miles across and may not be potable, as the researchers predict it must be extremely salty to stay liquid in the -10 and -30 Celsius temperatures.
If it is liquid water, the intense saltiness would make it hard for life, at least life as known on Earth, to survive in the lake, Lunine said.
In Lake Vostok's case, the frigid water serves as a refuge for species that probably got their start millions of years ago. The results, published July 25 in Science, provide some resolution to a decades-long debate over whether a sizable body of liquid water is present on Mars.
If life did arise from those early, cozy conditions, it could have moved underground as the surface cooled and dried. But the radar reflections could be produced by a layer of water less than a meter thick, so it could be just a thin layer of liquid lining the base of the ice sheet.
It has always been suspected that the Red Planet is not as dry and arid as it looks. The profiles contain "evidence of liquid water trapped below the ice of the South Polar Layered Deposits", according to the study.
Scientists have uncovered a "a stable body of liquid water" on Mars, in what some are calling a "game changer" in the search for alien life. While the temperature is expected to be well below freezing point, only pure water freezes at 0 degrees, notes the release.
Previously, there has been some suggestions about water on Mars, like droplets of water condensing on the Phoenix lander or as the possible cause of recurring slope lineae, which are seasonal dark streaks on Martian slopes.
"I think the chances now of finding a place to look for current life have gone up", Scott Hubbard, the first director of NASA's Mars program, told NBC News. It also opens up the possibility that it is a reservoir not just of water, but of life.
The instrument uses pulses of radar to study the interior structure of the planet and has been orbiting Mars on the Mars Express European spacecraft since 2003.
"But there are terrestrial organisms that can survive and thrive, in fact, in similar environments".
This image provided by the ESA/INAF shows an artist's rendering of the Mars Express spacecraft probing the southern hemisphere of Mars.
The discovery was made using a radar instrument on board the Mars Express orbiter, which works by bouncing low-frequency electromagnetic waves off the surface of the planet then analysing the data that returns. There, as on Mars, the surface is barren, but is more hospitable farther down. On Earth, thousands of species of microbial life have been found in Lake Vostok, a huge lake buried under almost 4km of ice in Antarctica. "This is very big news for astrobiology on Mars", said NASA's McKay.