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View Full Version : In search for water on Mars, clues from Antarctica (Forwarded)


Andrew Yee[_1_]
December 21st 07, 07:27 PM
Research Communications
Ohio State University

Contact:
Berry Lyons, (614) 688-3241

Written by:
Pam Frost Gorder, (614) 292-9475

12/7/07

IN SEARCH FOR WATER ON MARS, CLUES FROM ANTARCTICA

COLUMBUS, Ohio -- Scientists have gathered more evidence that suggests
flowing water on Mars -- by comparing images of the red planet to an
otherworldly landscape on Earth.

In recent years, scientists have examined images of several sites on Mars
where water appears to have flowed to the surface and left behind a trail of
sediment. Those sites closely resemble places where water flows today in the
McMurdo Dry Valleys in Antarctica, the new study has found.

The new study bolsters the notion that liquid water could be flowing beneath
the surface of Mars. And since bacteria thrive in the liquid water flowing
in the Dry Valleys, the find suggests that bacterial life could possibly
exist on Mars as well.

Researchers have used the Dry Valleys as an analogy for Mars for 30 years,
explained Berry Lyons, professor of earth sciences and director of the Byrd
Polar Research Center at Ohio State University.

Lyons is lead principal investigator for the National Science Foundation's
Long Term Ecological Research (LTER) Network, a collaboration of more than
1,800 scientists who study the ecology of sites around the world.

One of the LTER sites is in the Dry Valleys, a polar desert in Antarctica
with year-round sal****er flowing beneath the surface. With temperatures
that dip as low as negative 85 degrees Fahrenheit, it's as cold as the
Martian equator, and its iron-rich soil gives it a similar red color.

"If you looked at pictures of both landscapes side by side, you couldn't
tell them apart," Lyons said.

In the new study, LTER scientists did just that -- they compared images of
water flows in the Dry Valleys to images of gullies on Mars that show
possible evidence of recent water flow.

Team member Peter Doran of the University of Illinois at Chicago presented
the results Tuesday, December 11, 2007, at the American Geophysical Union
meeting at San Francisco .

The scientists' conclusion: the Martian sites closely resemble sites in the
Dry Valleys where water has seeped to the surface.

The water in the Dry Valleys can be very salty -- it's full of calcium
chloride, the same kind of salt we sprinkle on roadways to melt ice. That's
why the water doesn't freeze. Natural springs form from melted ground ice or
buried glacier ice, and the sal****er percolates to the surface.

"Even in the dead of winter, there are locations with salty water in the Dry
Valleys ," Lyons said. "Two months a year, we even have lakes of liquid
water covered in ice."

But after the water reaches the surface, it evaporates, leaving behind salt
and sediment.

The same thing would happen on Mars, he added.

Because the suspected sediment sites on Mars closely resemble known sediment
sites in the Dry Valleys, Lyons and his colleagues think that liquid
sal****er is likely flowing beneath the Martian surface.

Lyons, who has led many expeditions to Antarctica, said that his team will
continue to compare what they learn on Earth to any new evidence of water
uncovered on Mars.

As they walk across the Dry Valleys, they can't help but compare the two.

"There's just something about that landscape, about being so far from
civilization, that makes you think about other worlds," he said.

Images to acccompany this story are available at
http://researchnews.osu.edu/archive/saltmarspix.htm