Explore Antarcticas Hidden Lake Vostok

Explore Antarcticas Hidden Lake Vostok One of the largest lakes on planet Earth is an extreme environment hidden beneath a thick glacier near the South Pole. Its called Lake Vostok, buried beneath nearly four kilometers of ice on Antarctica. This frigid environment has been hidden from sunlight and Earths atmosphere for millions of years. From that description, it sounds like the lake would be an icy trap devoid of life. Yet, despite its hidden location and terribly inhospitable environment, Lake Vostok teems with thousands of unique organisms. They range from tiny microbes to fungi and bacteria, making Lake Vostok a fascinating case study in how life survives in hostile temperatures and high pressure. Finding Lake Vostok The existence of this sub-glacial lake took the world by surprise. It was first found by an aerial photographer from Russia who noticed a large smooth impression near the South Pole in East Antarctica. Followup radar scans in the 1990s confirmed that something was buried under the ice. The newly discovered lake turned out to be quite large: 230 kilometers (143 miles long) and 50 km (31 miles) wide. From its surface to the bottom, it is 800 meters (2,600) feet deep, buried under miles of ice. Lake Vostok and Its Water There are no subterranean or sub-glacial rivers feeding Lake Vostok. Scientists have determined that its sole source of water is melted ice from the ice sheet that hides the lake. Theres also no way for its water to escape, making Vostok a breeding ground for underwater life. Advanced mapping of the lake, using remote sensing instruments, radar, and other geologic research tools, show that the lake sits on a ridge, which may be harboring heat in a hydrothermal vent system. That geothermal heat (generated by molten rock beneath the surface) and the pressure of the ice on top of the lake keep the water at a constant temperature. The Zoology of Lake Vostok When Russian scientists drilled cores of ice out from above the lake to study the gases and ices laid down during different periods of Earths climate, they brought samples of frozen lake water up for study. Thats when the life forms of Lake Vostok were first discovered. The fact that these organisms exist in the lake water, which, at -3 ° C, is somehow not frozen solid, raises questions about the environment in, around, and under the lake. How do these organisms survive in these temperatures? Why hasnt the lake frozen over? Scientists have now studied the lakes water for decades. In the 1990s, they began to find microbes there, along with other types of miniature life, including fungi (mushroom-type life), eukaryotes (the first organisms with true nuclei), and assorted multicellular life. Now, it appears that more than 3,500 species live in the lakes water, in its slushy surface, and in its frozen muddy bottom. Without sunlight, Lake Vostoks living community of organisms (called extremophiles, because they thrive in extreme conditions), rely on chemicals in rocks and heat from the geothermal systems to survive. This isnt terribly different from other such life forms found elsewhere on Earth. In fact, planetary scientists suspect that such organisms could thrive very easily in extreme conditions on icy worlds in the solar system. The DNA of Lake Vostoks Life Advanced DNA studies of the Vostokians indicate that these extremophiles are typical of both freshwater and saltwater environments and they somehow find a way to live in the cold waters. Interestingly, while the Vostok life forms are thriving on chemical food, they themselves are identical to bacteria that live inside of fish, lobsters, crabs, and some types of worms. So, while the Lake Vostok life forms may be isolated now, they are clearly connected to other forms of life on Earth. They also make a good population of organisms to study, as scientists ponder whether or not similar life exists elsewhere in the solar system, particularly in the oceans beneath the icy surface of Jupiters moon, Europa. Lake Vostok is named for Vostok Station, commemorating a Russian sloop used by Admiral Fabian von Bellingshausen, who sailed on voyages to discover Antartica. The word means east in Russian. Since its discovery, scientists have been surveying the under-ice landscape of the lake and the surrounding region. Two more lakes have been found, and that now raises the question about connections between these otherwise-hidden bodies of water. In addition, scientists are still debating the history of the lake, which appears to have formed at least 15 million years ago and was covered over by thick blankets of ice. The surface of Antarctica above the lake routinely experiences very cold weather, with temperatures dipping down to -89 ° C. The biology of the lake continues to be a major source of research, with scientists in the U.S., Russia, and Europe, studying the water and its organisms closely to understand their evolutionary and biological processes. Continued drilling poses a risk to the ecosystem of the lake since contaminants such as antifreeze will harm the organisms of the lake. Several alternatives are being examined, including hot-water drilling, which may be somewhat safer, but it  still poses a danger to lake life.