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University of Colorado scientist Ted Scambos is sure there will be microbes found in Lake Vostok when the long process of examining samples starts _ something that may be months away because of logistical problems. He said ice many feet above the lake had bacteria, so it makes sense that the lake does.

Still, what makes Lake Vostok more important than other extreme environments is its incredible isolation.

For example, in Atacama, life probably blew in from elsewhere, NASA astrobiologist Chris McKay said. But Lake Vostok microbes, if found, could not have blown in.

More than 10 million years ago there was little or no ice there, so life could easily have existed then. But with no heat or sunlight after the ice set in, life there now would have had to find another way of getting energy, said molecular chemist and astrobiologist Steve Benner. And that’s key.

If life finds a way to adapt to strange conditions in this awful place, why couldn’t it live on Jupiter’s moon Europa or Saturn’s moon Enceladus, scientists ask. Both bodies have water trapped under crusts of ice, just like Lake Vostok, and are both prime targets in the search for life beyond Earth. The big disagreement among scientists is not about the potential for life on those two moons, but which one has the most potential and should be explored first.

It also means Mars could harbor life deep underground, McKay said.

“The broadest lesson that I think we can derive is that given liquid water, life can negotiate just about everything else,” McKay said.

So far, except for the surprise shrimp that stunned a NASA Antarctic researcher and the odd tubeworms alongside ocean vents, most of the life forms are so small we can’t see them. They are single-cell microbes or a tad more complex.

But that’s a big deal because microbes evolve. For 90 percent of the time that life existed on Earth, there were only microbes, said Bruce Jakosky, a professor of geological sciences at the University of Colorado. Microbes are “where we come from,” he said.

Jakosky and McKay said it also could eventually mean that life started in more than one place in the universe.

“If there’s microbial life widespread throughout the galaxy, that increases the chances that there’s intelligent life elsewhere,” Jakosky said.



NASA’s astrobiology institute: