Russian Science Team Penetrates Lake Vostok
Diagonal view of the rocks beneath the ice sheet (brownish color) and the surface of Lake Vostok (blue).
The lake, which lies four kilometres below the icy surface of Antarctica, is unique in that it’s been completely isolated from the other 150 subglacial lakes on the continent for such a long time. It’s also oligotropic, meaning that it’s supersaturated with oxygen — levels of the element are 50 times higher than those found in most typical freshwater lakes.
Since 1990, the Arctic and Antarctic Research Institute in St Petersberg in Russia has been drilling through the ice to reach the lake, but fears of contamination of the ecosystem in the lake have stopped the process multiple times, most notably in 1998 when the drills were turned off for almost eight years.
Now, the team has satisfied the Antarctic Treaty Secretariat, which safeguards the continent’s environment, that it’s come up with a technique to sample the lake without contaminating it. Valery Lukin told New Scientist: “Once the lake is reached, the water pressure will push the working body and the drilling fluid upwards in the borehole, and then freeze again.” The next season, the team will bore into that frozen water to recover a sample whose contents can then be analysed.
The drill bit currently sits less than 100 metres above the lake. Once it reaches 20-30 metres, the mechanical drill bit will be replaced with a thermal lance that’s equipped with a camera. Time is short, however. It’s possible that the drillers won’t be able to reach the water before the end of the current Antarctic summer, and they’ll need to wait another year before the process can continue.
When the sample can be recovered, however, it’s hoped that it’ll shed light on extremophiles — lifeforms that survive in extreme environments. Life in Lake Vostok would need adaptions to the oxygen-rich environment, which could include high concentrations of protective enzymes. The conditions in Lake Vostok are very similar to the conditions on Europa and Enceladus, so could also strengthen the case for extraterrestrial life.
