This ice was once water in the lake that refroze onto the bottom of the ice sheet, Cary explained. We have no direct samples of the lake itself, only this indirect sampling of the refrozen ice above it because drilling into the lake without taking extensive precautions could lead to the lake's contamination. The borehole made to collect the ice is filled with a mixture of jet fuel, kerosene, and CFCs to keep it from closing, Cary noted. Since the lake has not had direct contact with the surface world for at least 15 million years, this would be a contamination of one of the most pristine environments on Earth, he said.
Cary said the decontamination procedure was the most complicated and complete ever attempted, requiring the use of an isolation chamber for the actual melting, concentration of the meltwater through a special filtering system, use of bleaching solutions for the destruction of any contaminating bacteria or DNA from the outside of the core, and the wearing of sterile jump suits for all of the laboratory personnel, among other measures.
Although other scientific projects have identified the microorganisms living in the Vostok water, they have not revealed what these little one-celled organisms do or how they have become adapted to an environment that is eternally dark, cold and so isolated that food and energy sources are likely rare and hard to come by.
This research is important because it will give us insight into how microbes can survive in a very energy-limited system, Smith said. She intends to pursue a career in academia after she completes her doctorate at UD's College of Marine and Earth Studies.
Most of our planet is permanently cold and dar
|Contact: Tracey Bryant|
University of Delaware