Sabtu, 05 November 2011
Journey to Antarctica: Mission to Drill Lake Buried Under 2 Miles of Ice Read more: http://www.foxnews.com/scitech/2011/10/11/journey-to-antarctica-mission-to-drill-into-ice-buried-lake
A team of British engineers is set to begin a journey to a lake hidden beneath nearly 2 miles of Antarctic ice.
The explorers depart next week for Antarctica on the first stage of an ambitious scientific mission to collect water and sediment samples from a lake buried beneath 1.8 miles (3 kilometers) of solid ice. This mission will hopefully yield new knowledge about the evolution of life on Earth and other planets, and will provide vital clues about the Earth's past climate.
Transporting nearly 80 tons of equipment, the "advance party" will make a journey almost 10,000 miles (16,000 km) from the United Kingdom to the subglacial Lake Ellsworth on the West Antarctic Ice Sheet. It is one of the most remote and hostile environments on Earth, with temperatures that hover at minus 13 degrees Fahrenheit (minus 25 degrees Celsius). Their task is to prepare the way for the "deep-field" research mission that will take place next year, when the team of scientists and engineers will live in tents, spending around three months working above the lake.
British researchers look to uncover clues to the evolution of life on Earth
In October 2012, a team of 10 scientists and engineers will use state of the art hot-water drilling technology to make a borehole through the ice to the lake below. They will then lower a titanium probe to measure and sample the water followed by a corer to extract sediment from the lake.
Lake Ellsworth is likely to be the first of Antarctica's subglacial lakes to be measured and sampled directly through the design and manufacture of space-industry standard "clean technology," the team noted.
Antarctica is home to 387 known subglacial lakes, some of the most pristine environments on Earth. Lake Vostok in East Antarctica is the most well-known of these lakes. A Russian team has been trying to drill and collect samples from Vostok, but were unable to do so before winter set in this year.
For years, scientists have speculated that new and unique forms of microbial life could have evolved in the cold, pitch-black and isolated environment of these subglacial lakes. Sediments on the lakebed are likely to reveal vital clues about the history of life in the lake and the ancient history of the West Antarctic Ice Sheet, including past collapse.
"For almost 15 years, we've been planning to explore this hidden world," said mission leader Martin Siegert from the University of Edinburgh. "It's only now that we have the expertise and technology to drill through Antarctica's thickest ice and collect samples without contaminating this untouched and pristine environment."
David Pearce, science coordinator at the British Antarctic Survey and part of the team leading the search for life in the lake water, said the mission will be a success no matter what is found.
"Finding life in a lake that could have been isolated from the rest of the biosphere for up to half a million years will tell us so much about the potential origin of and constraints for life on Earth, and may provide clues to the evolution of life on other extraterrestrial environments," Pearce said in a statement. "If we find nothing, this will be even more significant because it will define limits at which life can no longer exist on the planet."
The unique 16-foot-long (5 meters) water-sampling probe will collect 24 water samples at different lake depths. It will also capture the top layer of sediments where the lake-floor meets the water.
The sediment corer can extract a core up to 10 feet (3 m) long. The corer is strong enough to penetrate even the most compacted glacial sediments to extract a core sample.