Did you know there are hundreds of lakes underneath the
Antarctic ice sheet? These bodies of water, which were detected by ground penetrating radar, are about 800 meters under the ice
and are totally isolated from the outside world. This means that anything
living in those lakes has had no contact with the outside world since the lakes’
formation. This is a treat that’s too good to pass up for either biologists or astrobiologists. So far it looks
like they won’t be disappointed.
Scientists have discovered that under the massive Antarctic ice sheets there lies a vast hydrological system of liquid water. This water exists because geothermal heat flow from below, coupled with pressure, movement, and the insulating nature of the ice sheet above, is great enough to maintain some areas at the base of the ice sheet above the freezing point, even in the extreme cold of Antarctica. In topographic depressions there are hundreds of lakes, both large and small; some are isolated, but many are interconnected by water channels and large areas of saturated sediments, the water eventually running out into the Southern Ocean as the ice sheet becomes a floating ice shelf.
WISSARD Project.
Scientists have discovered that under the massive Antarctic ice sheets there lies a vast hydrological system of liquid water. This water exists because geothermal heat flow from below, coupled with pressure, movement, and the insulating nature of the ice sheet above, is great enough to maintain some areas at the base of the ice sheet above the freezing point, even in the extreme cold of Antarctica. In topographic depressions there are hundreds of lakes, both large and small; some are isolated, but many are interconnected by water channels and large areas of saturated sediments, the water eventually running out into the Southern Ocean as the ice sheet becomes a floating ice shelf.
WISSARD Project.
Of course, we first have to find out what’s down there. To
that end, NASA is funding the Whillans Ice Stream Subglacial Access Research
Drilling (WISSARD) project. The goal of this project is to drill a hole
through the ice and see what’s in the lake beneath it. This is vastly more
complicated than it sounds for several reasons. To begin with, the team had to
drill a hole all the way to Lake Whillans, half a mile down through the ice. Next,
the instruments had to be threaded down that long hole and then brought back up
with samples and without scraping along the sides and becoming damaged. Also,
the instruments had to be completely sterile so as not to contaminate any
findings. And lastly, did I mention this was Antarctica? This is not the most
hospitable place in which to stand around doing fieldwork.
Alberto Behar, co-investigator of the WISSARD project, gives us a tour:
Although the findings are preliminary, there do appear to be
microbes in the subglacial lake water. This is good news for people hoping to
find life under the ice sheets of other worlds, such as Europa or Enceladus.
The next step is to see how closely these samples resemble other forms of life
on Earth.
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