The surface above Lake Vostok, hidden under more than a kilometer of ice, looks like most of Antarctica’s landscape—flat, barren, and icy. The best way to detect a subglacial lake is through remote sensing. Credit: M. Studinger, Lamont-Doherty Earth Observatory, Columbia University
Scientists Race To Breach Antarctica's Lake Vostok
Russian scientists are set to pierce through Antarctica’s frozen surface to reveal the secrets of an icebound lake that has been sealed deep there for the past 15 million years.
Alexei Turkeyev, head of the Russian polar Vostok Station, told Reuters by satellite phone that scientists have “only a bit left to go.” His team has been drilling for weeks in a race to reach the lake -- buried 12,000 feet beneath the polar ice cap -- before the end of the brief Antarctic summer.
With the quickly returning onset of winter, scientists will be forced to leave on the last flight out on February 6. “It's minus 40 (Celsius/Fahrenheit) outside,” said Turkeyev. “But whatever, we're working. We're feeling good. There's only 5 meters left until we get to the lake so it'll all be very soon.”
Scientists are hoping the lake will reveal new forms of life and show how life evolved may have evolved in the times before the ice age. The lake could also offer scientists a glimpse of what conditions exist for life in similar extremes on Mars and Jupiter’s moon Europa.
Location of Lake Vostok marked in red
“It's like exploring an alien planet where no one has been before. We don't know what we'll find,” Valery Lukin of Russia's Arctic and Antarctic Research Institute (AARI) in St Petersburg, which oversees the expedition, told Reuters.
The discovery of the hidden network of sub-glacial lakes of Antarctica in the 1990s has sparked much enthusiasm among scientists the world over.
Explorers from the US and Britain are following the trail of Russia’s scientists with their own missions to probe other buried lakes, which are among the last of the world’s hidden and unexplored areas.
“It's an extreme environment but it is one that may be habitable. If it is, curiosity drives us to understand what's in it. How is it living? Is it flourishing?,” Martin Siegert, head of the University of Edinburgh's School of Geosciences, who is leading a British expedition to a smaller polar lake, told Reuters reporter Alissa de Carbonnel.
Experts explain that the ice sheet traps in the planet’s geothermal heat and prevents the lakes from freezing. Sediment from the lake might show scientists a window to the past, back millions of years to tropical prehistoric times, said Lukin.
Lake Vostok is the largest, deepest and most isolated of the frozen continent’s 150 sub-glacial lakes. It is overly saturated with oxygen, more so than any other known environment on Earth.
John Priscu of Montana State University, a chief scientist with the U.S. program to explore another Antarctic lake, said Russian scientists are “leading the way with a torch.”
Russian research station at Lake Vostok
Priscu said beneath the frozen crust, far from any sunlight, in the vast sub-glacial lake creatures may lurk around thermal vents in the lake’s depths. “I think Lake Vostok is an oasis under the ice sheet for life. It would be really wild to thoroughly sample... But until we learn how to get into the system cleanly that's an issue,” he told Reuters.
Explorers, about to breach the lake for the first time, now face an important question: How do we go where no one has gone before without spoiling it or bringing back some foreign virus?
“I feel very excited but once we do it there is no going back,” said Alexei Ekaikin, a scientist with the expedition at Vostok Station. “Once you touch it, it will be touched forever.”
Researchers working at Vostok Station produced one of the world's longest ice cores in 1998. A joint Russian, French, and U.S. team drilled and analyzed the core, which is 3,623 metres (11,886 ft) long. Ice samples from cores drilled close to the top of the lake have been assessed to be as old as 420,000 years, suggesting that the lake was sealed under the icecap 15 million years ago. Drilling of the core was deliberately halted roughly 100 metres (300 ft above the suspected boundary where the ice sheet and the liquid waters of the lake are thought to meet. This was to prevent contamination of the lake from the 60 ton column of freon and kerosene Russian scientists filled it with to prevent the borehole from collapsing and freezing over.
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