Voltaire....OT...Re 50 million year old ice....Believe thats a misprint.....long article follows....time span discussed a bit at the bottom.....
Tiny Life Under Antarctica
Clues for Life Beyond Earth
Special to ABCNEWS.com
Lake Vostok would be a tough place
to live.
This liquid body of water lies at least
12,000 feet below the ice of Antarctica. It
sits beneath a Russian research station that
has seen the lowest temperatures ever
recorded on this planet: minus 126.9 degrees Fahrenheit.
Deprived of
sunlight, and under
pressure from an ice
cap more than two
miles thick, Lake
Vostok seems an
unlikely place for
anything to survive.
But scientists are
finding tantalizing
evidence that the lake
may contain life, at
least very simple life
forms. Bacteria related
to modern microbes called proteobacteria and
actinomycetes have been found in the ice just 393 feet
above the lake.
Scientists from Montana State University and the
University of Hawaii discovered the bacteria in ice from
an 11,800-foot well drilled by Russian researchers. The
core is the deepest ice ever recovered, but they halted
drilling nearly 400 feet above the lake.
No one is quite sure how to
tap into the lake without
contaminating it, so Vostok
remains isolated until protection
of the lake can be assured.
Why all this fuss over a body
of water that no one is ever likely
to see?
NASA scientists believe Lake
Vostok may offer a glimpse of life
on this planet under conditions
similar to other bodies in our solar
system. Europa, a frozen moon of Jupiter, is believed to
have liquid water beneath its icy crust. And some
scientists believe liquid water may exist beneath the polar
regions of Mars.
Internal Heat
Europa, with surface temperatures of minus 260 degrees
Fahrenheit, doesn?t seem like a harbor for life. But
scientists believe its interior is tormented by the
gravitational tug of Jupiter. Those tidal forces could cause
hot spots beneath its ocean, possibly similar to the
hydrothermal vents that have provided thriving habitats on
Earth?s ocean floor.
?We?re pretty sure there is an ocean on Europa,? says
Christopher McKay, an astrobiologist at NASA?s Ames
Research Center. But Europa?s ocean is covered by ice
about 10 miles thick, distant and difficult to check for life.
Lake Vostok, McKay says, may tell us how.
?What could be happening is if there are any bugs in
the ocean (of Europa), they would freeze into the ice on
top of the ocean and with time that ice could be carried
toward the surface,? McKay says. ?So we might find
evidence of those bugs in ice a lot closer to the surface
than 10 miles down.?
Yet it?s still unknown whether Lake Vostok itself has
life, according to the researchers, who published their
findings in the Dec. 10 issue of the journal Science.
Home-Grown?
Biologist John Priscu of Montana State University, leader
of the team, said that it?s not even possible to tell if the
microbes were alive or dead, or where they originated
when they iced up. They could have been blown onto
Antarctica from the Patagonian deserts of South America
and then trapped in an icy grave.
Or they could have originated in the lake itself and
become trapped as the water froze over. If so, they could
be more than half a million years old.
If microbes once lived in the lake and were trapped in
the ice as it formed over the lake, then the same process
may have taken place on other celestial bodies, such as
Europa.
There are, however, enormous differences between
the two bodies. If these microbes are even several million
years old, as some scientists believe, they originated on a
planet that was covered with biological activity, not a
barren rock like Europa.
Yet scientists believe water is the one essential
ingredient for life, so frozen lakes may offer the best hope
of finding evidence of life elsewhere.
On this planet, at least, life seems to crop up wherever
there is water.
Life All Around
?Everywhere we go, we are turning up new
microorganisms,? Cynan Ellis-Evans, a microbiologist with
the British Antarctic Survey, told delegates to an
international meeting in Cambridge, England, earlier this
year. ?It doesn?t matter how extreme the environment is,
we find them. We can go to hot springs, or situations that
are poisonous, and we still find microorganisms.?
Lake Vostok contains other mysteries. Why, for
instance, is the lake liquid, as indicated by radar studies?
Maybe the mere weight of the ice creates enough
pressure to keep the water from freezing, some scientists
believe.
If so, drilling into it will require great caution. Experts
note that if the Russians accidentally puncture the ice cap
above the lake, water might gush up the drill hole with
deadly force.
Scientists also want to know what lies below the lake.
Ice cores from the Vostok station have allowed
scientists to study what the climate would have been the
past 400,000 years. If samples could be collected from
the bottom of the lake, that could extend the record to
millions of years.
These frozen time capsules will have to sit a little
longer. ...Tim |
