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Like Sputnik, but Colder

Nearly four kilometers under the surface of the Antarctic ice is Lake Vostok, a giant freshwater lake that's the world's third-largest by volume. It's existed for 35 million years, and it's been sealed off from the air for the past 15 million of those. No human has peeked under that ice. The water could hold ancient forms of life that we've never seen before.

Knowing it's there, do do you leave a pristine time capsule alone? Or do you fire up your giant drill, grab a few thousand gallons of antifreeze, and hack your way in there? A team of Russian scientists, knowing their answer (and apparently never having seen this episode of The X-Files), has been trying their hardest to get through the ice. Last week they were within 30 meters of the ancient lake when they had to quit.

The Russians have been trying to crack the surface of Lake Vostok since the 1990s, with many delays. After finally coming up with a plan to tap into the lake that was deemed scientifically acceptable, they began their last push (they thought) in January. As the end of the Antarctic summer approached, the team ran their drill 24 hours a day. But on February 6, they had to stop and high-tail it off the continent before dropping temperatures stranded them there. If they stayed in Antarctica any longer, their airplane's hydraulic fluid might have frozen. They'll return in the next Antarctic summer to finish what they started.

What might they find in Lake Vostok? There could be nothing living there; the lake is under total darkness and high pressure from the ice above it. If nothing else, there could be interesting microscopic fossils on the bottom of the lake. But if there are living microorganisms in the water, they could tell us what life looked like tens of millions of years ago, or what previously unknown tricks life uses to adapt to extreme conditions.

There are some concerns, though, that the Russian team's plan is unsafe. The chemicals they're using to lubricate their drill and keep the surrounding ice from refreezing could contaminate the lake, for one. Getting into the lake and finding out that you killed the world's oldest organisms would sure be a blow to morale. The Russians say their plan prevents that: they'll stop drilling just short of the water's surface, then retract their drill, letting the higher pressure of the lake push fresh water up into the hole. The water will refreeze, and the team will extract it as an ice core, never having to dip their instruments into the unpolluted water.

At least one scientist has a different concern. Montana State University ecologist John Priscu, who will soon be part of an American team drilling into other Antarctic lakes, says the waters of Lake Vostok are full of gases. Once the Russians break through the surface, Priscu thinks lake water could come shooting back at them like celebratory champagne. "You'd geyser out the top, and you'd drain the lake into the atmosphere," he says.

Next winter (in northern-hemisphere seasons, that is), we'll find out whether Lake Vostok is a hotbed of new life forms or a huge geyser-involving catastrophe. It could also be kind of a letdown. But don't worry, the Antarctic excitement won't end there: In a couple more years, the Russians plan to send down a swimming robot.

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