The New York Times reports that a Russian research team has drilled through 4 km (2-1/2 miles) of Antarctic ice to reach one of the world’s largest freshwater lakes. The lake, about the size of Lake Ontario, had been sealed off for at least the last 15 million years.
If it’s confirmed that the lake contains microbes—according to the article, some were found but it’s not yet clear whether their source was the lake or the drilling fluid—hopes would be raised that Jupiter’s moon Europa, with its liquid water surface encased in ice, and thin, oxygen atmosphere, might also harbor life.
The above video, produced by BBC2 in 2000, is a bit out of date. The technique used to keep the lake water pristine was to pump the drilling fluid out of the borehole so as to reduce the pressure in the shaft. When the surface of the lake was breached, the lake water, itself under pressure from the weight of 4km of ice, shot up through the shaft pushing out any remaining fluid, then refroze at the end of the borehole, forming an icy plug.
Here’s a link to the New York Times article:
Drilling Reaches Lake Vostok, Long Trapped Under Antarctic Ice Sheet
Here’s a link to a Wired article:
Russian Drill Penetrates 14-Million-Year-Old Antarctic Lake