Posted to sci.astro:

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From: rgregoryclark@yahoo.com (Robert Clark)
Newsgroups: sci.astro,sci.bio.misc,alt.sci.planetary,rec.arts.sf.science
Subject: Re - Possibilities for complex life on Europa.
References: <3dSZa.2102$l96.263863@news20.bellglobal.com>
NNTP-Posting-Host: 68.81.141.219
Message-ID: <832ea96d.0308112051.ed402c2@posting.google.com>

This research shows Lake Vostok to have high levels of oxygen. It had
been thought that Lake Vostok would have low levels of oxygen because
most oxygen in bodies of water comes from diffusion from the
atmosphere, and this mechanism would not be available for the
permanently ice-covered lake. For this reason most scientists thought
there could not be advanced life that could exist there.
A similar argument had been made towards the Jovian moon Europa.
However, this new research leaves open the possibility advanced life
could exist in Lake Vostok and therefore might possibly also exist on
Europa.
I discussed some possibilities for how advanced life might exist on
Europa in a prior sci.astro post:

From: Robert Clark (rgclark@my-deja.com)
Subject: Possibilities for complex life on Europa.
Newsgroups: sci.astro, sci.bio.misc, alt.sci.planetary
Date: 2001-01-27 19:42:02 PST
http://groups.google.com/groups?&selm=9503h8$tbv$1@nnrp1.deja.com

Bob Clark

2010: Odyssey Two
by Arthur C. Clarke
11. Ice and Vacuum, p. 74
'Who is it?' whispered someone, to a chorus of shushes. Floyd
raised his hands in a gesture of ignorance - and, he hoped, innocence.
'... know you are aboard Leonov... may not have much time...
aiming my suit antenna where I think...' The signal vanished for
agonizing seconds, then came back much clearer, though not appreciably
louder.
'... relay this information to Earth. Tsien destroyed three hours
ago. I'm only survivor. Using my suit radio - no idea if it has enough
range, but it's the only chance. Please listen carefully. THERE IS
LIFE ON EUROPA. I repeat: THERE IS LIFE ON EUROPA.'
The signal faded again. A stunned silence followed that no one
attempted to interrupt. While he was waiting, Floyd searched his
memory furiously. He could riot recognize the voice - it might have
been that of any Western-educated Chinese. Probably it was someone he
had met at a scientific conference, but unless the speaker identified
himself he would never know.
'... soon after local midnight. We were pumping steadily and the
tanks were almost half full. Dr Lee and I went out to check the pipe
insulation. Tsien stands - stood - about thirty metres from the edge
of the Grand Canal. Pipes go directly from it and down through the
ice. Very thin - not safe to walk on. The warm upwelling...'
Again a long silence. Floyd wondered if the speaker was moving,
and had been momentarily cut off by some obstruction.
'... no problem - five kilowatts of lighting strung up on the
ship. Like a Christmas tree - beautiful, shining right through the
ice. Glorious colours. Lee saw it first - a huge dark mass rising up
from the depths. At first we thought it was a school of fish - too
large for a single organism - then it started to break through the
ice..."
http://www.amazon.com/exec/obidos/tg/detail/-/0345303067/002-7831820-4340819

Andrew Yee <ayee@nova.astro.utoronto.ca> wrote in message news:<3dSZa.2102$l96.263863@news20.bellglobal.com>...
> Kathleen Burton
> NASA Ames Research Center, Moffett Field, Calif. August 11, 2003
> Phone: 650/604-1731 or 604-9000
> Email: Kathleen.M.Burton@nasa.gov
>
> RELEASE: 03-57AR
>
> RESEARCHERS FIND ANTARCTIC LAKE WATER WILL FIZZ LIKE A SODA
>
> Water released from Lake Vostok, deep beneath the south polar ice
> sheet, could gush like a popped can of soda if not contained, opening
> the lake to possible contamination and posing a potential health
> hazard to NASA and university researchers.
>
> A team of scientists that recently investigated the levels of
> dissolved gases in the remote Antarctic lake found the concentrations
> of gas in the lake water were much higher than expected, measuring
> 2.65 quarts (2.5 liters) of nitrogen and oxygen per 2.2 pounds (1
> kilogram) of water. According to scientists, this high ratio of
> gases trapped under the ice will cause a gas-driven "fizz" when the
> water is released.
>
> "Our research suggests that U.S. and Russian teams studying the lake
> should be careful when drilling because high gas concentrations could
> make the water unstable and potentially dangerous," said Dr. Chris
> McKay of NASA's Ames Research Center in California's Silicon Valley.
> McKay is lead author of a paper on the topic published in the July
> issue of the 'Geophysical Research Letters' journal.
>
> "We need to consider the implications of the supercharged water
> very carefully before we enter this lake," said Dr. Peter Doran, a
> co-author and associate professor of Earth and Environmental
> Sciences at the University of Illinois at Chicago.
>
> Lake Vostok is a rich research site for astrobiologists, because it
> is thought to contain microorganisms living under its thick ice
> cover, an environment that may be analogous to Jupiter's moon,
> Europa. Europa contains vast oceans trapped under a thick layer of
> ice. Russian teams are planning to drill into Lake Vostok's 2.48 mile
> (four kilometer) ice cover in the near future, and an international
> plan calls for sample return in less than a decade.
>
> An important implication of this finding is that scientists expect
> oxygen levels in the lake water to be 50 times higher than the oxygen
> levels in ordinary freshwater lakes on Earth. "Lake Vostok is an
> extreme environment, one that is supersaturated with oxygen," noted
> McKay. "No other natural lake environment on Earth has this much
> oxygen."
>
> The research also suggests that organisms living in Lake Vostok may
> have had to evolve special adaptions, such as high concentrations of
> protective enzymes, in order to survive the lake's oxygen-rich
> environment, the researchers say. Such defense mechanisms may
> also protect life in Lake Vostok from oxygen radicals, the dangerous
> byproducts of oxygen breakdown that cause cell and DNA damage.
> This process may be similar to that of organisms that scientists
> theorize may once have lived on Europa, whose ice layer and
> atmosphere are thought to contain radiation-produced radicals
> and oxygen.
>
> "We expect to find that the organisms in Lake Vostok are capable of
> overcoming very high oxygen stress," said co-author Dr. John Priscu,
> a geo-biologist at Montana State University in Bozeman. Priscu
> heads an international group of researchers that will deploy a
> remote observatory at Lake Vostok within three years and return
> samples within 10 years.
>
> The team also determined the ratios of gases in the lake. The
> scientists discovered that the air-gas mixture there, besides
> dissolving in the water, also is trapped in a type of structure
> called a 'clathrate'. In clathrate structures, gases are enclosed in
> an icy cage and look like packed snow. These structures form at the
> high pressure depths of Lake Vostok and would be unstable if brought
> to the surface.
>
> Lake Vostok is located 2.48 miles (four kilometers) beneath the East
> Antarctic Ice Sheet. The lake, and more than 70 other lakes deep
> beneath the polar plateau, are part of a large, sub-glacial
> environment that has been isolated from the atmosphere since
> Antarctica became covered with ice more than 15 million years ago.
> Scientists theorize that Lake Vostok probably existed before
> Antarctica became ice covered, and may contain evidence of
> conditions on the continent when the local climate was subtropical.
>
> For images and further information about plans to return research
> samples from Lake Vostok, go to:
>
> http://salegos-scar.montana.edu/
>
> The paper's authors also include K.P. Hand, Stanford University and
> Dr. D.T. Andersen, the SETI Institute.
>
> The research was jointly funded by NASA and the National Science
> Foundation.

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