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Life In Antarctic Ice May Compare To Mars
Source: Oregon State University (via Ndunlks)
Date: June 25th 1998
Written by: David Stauth
CORVALLIS, Ore. - Bacterial colonies are thriving underneath ice on one of the coldest, driest deserts on Earth, researchers have discovered, in conditions that might compare to those on Mars or Europa and provide insights for life forms that could be found elsewhere in our solar system.
The study will be reported Friday in the journal Science.
This study was conducted on ice-covered lakes in the McMurdo Dry Valleys of Antarctica, which has an average annual temperature about 68 degrees below zero and gets less than four inches of precipitation a year.
But in that frigid, arid environment, scientists at Oregon State University and four other institutions found liquid water pockets embedded about six feet deep in solid ice, where a combination of sediments, water and solar radiation during long summer days supports a viable population of bacteria.
"This is a very barren environment with virtually nothing we usually associate with living organisms," said Stephen Giovannoni, an associate professor of microbiology at Oregon State University. "But these photosynthetic cyanobacteria are alive, self-sufficient, and growing. They're able to live through the harsh freeze-thaw cycle of the seasons, fix nitrogen and release oxygen as they make carbohydrates from water and carbon dioxide."
"They have their own little world there we knew nothing about."
The nutritional requirements of these life forms are minimal, Giovannoni said - a little light, water, carbon dioxide, phosphate, nitrate and other minerals. But in fact the primitive life processes they are undertaking are quite similar to those that first formed the oxygen-rich atmosphere of Earth and made higher life forms possible.
And in the study, the researchers cite two locations where they feel conditions may exist that are similar to those found in barren Antarctica - Mars, and a large moon of Jupiter, Europa.
"It's been suggested that Mars is too dry and cold for life to exist," Giovannoni said. "But it's also known that both Mars and Europa have frozen water on or near their surfaces. We speculate that in conditions similar to those we observed in Antarctica, it would be a distinct possibility that similar life forms exist on Mars or Europa."
While Mars may have had extensive liquid water at one time, the researchers say in their report, it rapidly cooled and ice would have become, as it is today, the dominant form of water on Mars' surface. A search for fossil evidence of the most recent life on Mars' surface could be based on life within ice, they said.
The process of life formation is still largely unknown and very complex, Giovannoni said.
"Any cell, even a very basic cell such as those found in bacteria, is a very complicated thing," he said. "But experiments have shown you can get fairly complicated molecules and amino acids from the interaction of basic chemicals and electricity."
Giovannoni has studied bacteria all over the Earth, from the basalt rocks of deep sea floors to Antarctic ice cores, Yellowstone National Park hot springs and the bacterial plankton of Oregon's Crater Lake. Researchers continue to be amazed, he said, at how little is known about microbes, how few have actually been described, how they function and their ecological interaction with the rest of the world.
"Recent advances in molecular biology now allow us to identify these unknown organisms, and what we're learning is the world is full of bacteria we know virtually nothing about," he said. "I could probably isolate a new, previously unknown bacterium from the sole of your shoe."
Past research has been held back by lack of funding, Giovannoni said, as agencies seemed unsure that studies of bacteria, their evolution or behavior had any practical value. But new applications of bacterial research in understanding the global carbon cycle, creating new antibiotics or enzymes for industrial use have raised increasing interest, he said.
And the search for life elsewhere in the universe might first be successful, he said, when bacteria such as those being identified in Antarctica are one day found on Mars.

Thriving Bacteria Colonies Found
Source: Associated Press (via Ndunlks)
Date: June 25th 1998
Written by: Paul Recer
WASHINGTON (AP) - In a discovery that suggests life is possible on Mars or on a frozen moon of Jupiter, researchers say they have found colonies of bacteria thriving inside blocks of solid ice in lakes near the South Pole.
A team of researchers drilling through the perpetual ice filling shallow lakes in Antarctica, found teeming communities of microbes living and thriving in temperatures that seldom rose above the freezing point of water.
``This is more proof that life is a lot more hardy than we once thought,'' said Brian D. Lanoli of Oregon State University in Corvallis, co-author of study being published Friday in the journal Science.
If microbes can thrive in such frigid, hostile surroundings as the Antarctic lakes, he said, then it could perhaps also be found in the frozen seas of Europa, a moon of Jupiter, or the ice caps of Mars.
``Since we know there is ice elsewhere in our solar system, this discovery makes us wonder if life might not exist there also,'' said Stephen J. Giovannoi, another co-author from Oregon State.
The researchers found the microbial colonies while drilling ice cores from six lakes in Antarctica. As they drilled, they discovered a layer of dust and grit down six to eight feet below the surface of the always-frozen lakes.
Giovannoi said the grains of soil set up a ``special set of circumstances'' that made it possible for the microbes to live.
He said the dust was blown onto the ice during the Antarctic summer during a time when the sun is always shining. The grains absorbed solar heat and slowly sank into the ice. They reached a point, about six to eight feet down, and stopped sinking. A pocket of water formed around them and it was here that the microbes set up their community.
The lakes are located in what is, in effect, a desert. The air is very dry and precipitation is very low. Ice on the surface of the ponds actually is eroded away continually. Water pockets remain, however, at the same relative position, some six to eight feet from the surface, and eight to 10 feet above the bottom of the lakes.
The lively time for the microbes lasts only while the sun shines. Some of the organisms make food through photosynthesis from the weak polar sun. But more than half of the year is spent in twilight or total darkness of the extreme Antarctic seasons.
``Their temperature, even when they are active, is about zero degrees Centigrade (32 degrees F),'' said Giovannoi. This is just at the freezing point of water.
In the winter, however, he said, the temperatures in the ice drops to minus 20 F or colder.
``They (the microbes) are frozen in most of the year,'' said Giovannoi. And, yet, he said, they have adapted to the extreme conditions and are thriving.
``What at first glance appears to be a contradiction in terms (being frozen and leading an active life at the same time) turns out to be an exciting example of the adaptation of microorganisms to environmental extremes,'' the authors write in Science.
The physics that set up the conditions to enable the microbes to live suggests that such environments could exist on Mars, which may have frozen polar caps, or on Europa, a Jovian moon known to be covered with frozen water, the researchers said.
It may be possible that in soil or sand grains embedded in ice on can absorb enough solar energy to thaw the ice and create watery pockets where microbes could survive, said Giovannoi.
This creates a whole new niche for microbial communities to thrive in, he said.
Copyright 1998 The Associated Press. The information contained in the AP news report may not be published, broadcast, rewritten or otherwise distributed without prior written authority of The Associated Press.

Algae offers clues to life on other planets
Source: Reuters (via UASR)
Date: June 25th 1998
Written by: Michael Kahn, Reuters
WASHINGTON - Algae embedded beneath the ice covering six lakes in one of the Earth's coldest and driest deserts suggest life could exist in other parts of the universe, scientists said Thursday.
The microbes discovered in the McMurdo Dry Valleys of Antarctica were able to photosynthesize and decompose in extremely harsh conditions. Mars and Jupiter's moon Europa have similarly unrelenting environments and are places that scientists say other life in the universe might be possible.
"We've found a potential earthly model for what may occur on other frozen bodies," said John Priscu, an ecologist at Montana State University, who led the study, which was published in the journal Science.
The researchers collected ice samples in a region with an average annual temperature of about 4 degrees below zero and less than 4 inches of precipitation a year.
Fierce winds roiling the barren landscape stirred up sediment and blew dust particles containing life onto the frozen lakes located near the largest ice-free land mass on the continent, Priscu said.
"Here we have life in one of the most inhospitable places on the planet," he said.
Yet, during the 150 days of nonstop summer sunlight, the solar radiation provided enough energy for the seeds in the dust particles to become macrobiotic algae 6.6 feet below the ice surface, Priscu said. More important, the sun also created liquid water pockets in the frozen lake, making life possible for the algae, he added.
"Once you get liquid water, you are all set for life," Priscu said in a telephone interview. "We've discovered and defined life in the ice of the lake."
In order to withstand the extreme conditions, each organism depended on each other, he said. Some photosynthesized, while others acted as decomposers and recycled energy, he added.
Photosynthesis is a chemical process by which green plants synthesize organic compounds from carbon dioxide and water in the presence of sunlight. During that process, oxygen is released into the atmosphere.
"Every member of the community has a task," said Priscu. "Together all these tasks allow the community to survive in a pretty harsh environment."
Roland Psenner, a limnologist at Innsbruck University in Austria, wrote a commentary for the journal. He said that the discovery might be a model for scientists to use in the search for other life in the universe.
"It is a model of what may have happened on Mars and what may be happening on Europa," he said in a telephone interview.
The discovery was also important because it showed how life could spring from virtually nothing, he added.

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