The discovery of microbes thriving in the salty, sub-zero conditions of an Antarctic lake could raise the prospects for life on the Solar System’s icy moons.
Researchers found a diverse community of bugs living in the lake’s dark environment, at temperatures of -13C.
Details of the work have been outlined in the journal PNAS.
Lake Vida, the largest of several unique lakes found in the McMurdo Dry Valleys, contains no oxygen, is acidic, mostly frozen and possesses the highest nitrous oxide levels of any natural water body on Earth.
A briny liquid that is approximately six times saltier than seawater percolates throughout the icy environment.
Dr Cynan Ellis-Evans, from the British Antarctic Survey (Bas), who was not involved in the recent research, told BBC News: “There are various lakes that are very salty down there… but this is a really freaky one.
“It’s almost frozen solid right to the bottom. But you’ve got this brine ‘mush’ in the centre. For several years, they’ve been trying to get into it.”
He said the discovery of microbes at such low temperatures was “a very interesting discovery”.
The PNAS report’s publication comes as scientists fly out of the UK to join an effort to drill through the 3km of ice covering Lake Ellsworth, which is hidden beneath the West Antarctic Ice Sheet.
The discovery of any microbial communities here would be significant because the lake water may have been sealed off from the outside world for up to half a million years.
Late last year, a Russian team drilled through to Lake Vostok, an even larger lake covered by some 4km of ice. But preliminary analyses of lake water that froze on to the drill bit showed scant evidence for the presence of living organisms.
( via bbc.co.uk)