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The Ancient Lake in Antarctica

Lake Vostok is located in Antarctica under four km of ice. It is one of the largest sub glacial lakes and is approximately 250 km long and 50 km wide, with depths around 510m. Lake Vostok has been covered by the vast Antarctic ice sheet for up to 20 million 20 million years. After 30 years of drilling through the ice, the scientists announced that they are 100 meters away from the lake surface

History:

Andrey Kapitsa was the first to suspect that there lies a lake under the ice, however his idea was not supported by the technical data but only by his own observation of the flattened and smooth surface of the ice. In 1957, Russians established their Antarctic Research Base that has operated all year round for almost 40 years. In 1970, the British used their airborne radar to build possible topographical maps of Antarctica and were astonished to find that the Russian research station is located on top of the possible lake. However, only in 1996 this information was confirmed and was announced publicly. The Russians were drilling the ice core for almost three decades and had advanced to 3623 meters (11,886 feet) depth. The ice drilling was part of their research to study environmental changes on Earth since the last major Ice Age. The drill was stopped until 2003, restarted, only to be stopped again when it was discovered that the technology the Russians used could have contaminated the lake with Kerosene and Freon (used so ice would not freeze during drilling).

Lake Vostok:

Lake Vostok is an extreme environment, since it is supersaturated with oxygen. Concentrations of oxygen levels are about 50 times higher than those typically found in many lakes on Earth. The overall weight of the icecap sitting on top of the lake is believed to contribute to the high oxygen concentration.

Scientists were able to find bacteria in the refrozen ice that they believed to be once a part of the lake but was picked up by moving continental ice and froze (Ice that covers Antarctica is not standing still but is in constant motion). However, some scientists suggested that the bacteria that were found could have been introduced there by the drilling. Either way, the only way to prove that there is a life is to obtain sample from the lake and perform chemistry analysis.

The chance of possible tectonic activity could boost the chance of finding not only bacteria and microbes but even more complicated organisms, since the geophysical models of the lake topography revealed that earth crust could be very thin. [1] If it’s true, then thermal energy comes from tectonic processes and creates suitable environment for microbes. ( or maybe Godzilla J ). The lake is located close to mountains ridges that were formed during millions of years of tectonic plate shifting and breaking.

How to get there:

Since many scientists were concerned about contamination of the lake by conventional drilling techniques, a new approach was developed. When optimal distance (around 30 meters) between the ice core and the lake surface will be reached, the drill will be replaced with a small diameter thermal probe which will reach the lake itself. Lake water will then rise up to the drill hole, where it will freeze. The then frozen lake water will be extracted by drilling this new ice-core.

The conclusive part of the lake drill will be performed during next few month of 2011. So expect to see some “breaking news” soon, and remember steric hindrance page :)

Photo credits:

Photo1 : http://www.ldeo.columbia.edu/~mstuding/vostok.html

Photo 2 : http://www.flickr.com/photos/nsf_beta/4514670771/

photo 3 : http://www.ldeo.columbia.edu/~mstuding/slide_show/vostok_slideshow10.html

photo 4 : http://www.damninteresting.com/raiders-of-the-lost-lake

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