LakeVostok Location (source wikipedia) The Russian Geographical Society has announced that Russian scientists have finally completed the second drilling of Lake Vostok (Antarctica) and collected some clean water samples. Lake Vostok is believed to be the largest sub glacial lake in Antarctica, with an approximate size of 50x250  km. According to scientists, the lake has been eclogged in the ice half billion years ago and it may have been isolated form Earth ‘surface for several millions years, bearing good chances to have preserved traces of pristine life on Earth . The existance of lake was predicted by Russian scientists in the 1960s, when the " Vostok Research Station (Russia) was funded in inland Princess Elizabeth Land, Antarctica. A joint Russia-French-American research team has been working on reaching the surface of the lake (to collect samples of water) since the 90s. The surface of the lake ( approximately 4000 m under the ice) was eventually reached a first time in 2012, but the sample of the water collected were contaminated by the chemicals used for drilling. The second drilling was completed few days ago, and sample of clean water from the lake (no contaminated by the chemicals) have been collected.

Here is the press release from the Russian Geographical Society:

On January 25 during the Russian Antarctic Expedition researchers got water samples from subglacial Lake Vostok in Antarctica. This was announced by Minister of Natural Resources and Environmental Protection Sergey Donskoy: "After three years of hard work in the extreme Antarctic conditions the Russian polar explorers managed to complete the drilling of the well. Its depth along the length of the ice core is 3769.15m."

It is the second penetration into the relict lake. For the first time, the Russian scientists made their way to Vostok through the almost 4 km ice armor on February 5, 2012. They received the first water samples from the lake then, and found traces of living organisms in them. But drilling fluid from the well got into the samples, so the previously unknown life forms could not be clearly connected with Vostok.

To get clean water from the lake St. Petersburg Institute of Nuclear Physics (PINP) has created a special instrument. It is a two-meter titanium tube with a system of water pumping and heating. It can hold a liter of water and weights about 50 kg. The equipment has been thoroughly checked for leaks, the researchers have made sure that the drilling fluid consisting of a mixture of kerosene and freon does not get into it.

"This drilling is very important in terms of our priorities in research activities - Russian scientists are the only ones who can do it. The main objective of the drilling is to take samples of pure water that will get us the picture of what is happening in the lake," - said Honorable President of the Russian Geographical Society, Director of the Institute of Geography RAS, Academician Vladimir Kotlyakov.

(source: Russian Geographical Society)