From: UFO UpDates - Toronto <ufoupdates@virtuallystrange.net>
Date: Sat, 29 Mar 2003 07:08:22 -0500
Fwd Date: Sat, 29 Mar 2003 07:08:22 -0500
Subject: Scientists Finally Admit Mars Has Water + Life 



Source: Space.Com

http://www.space.com/scienceastronomy/mars_streaks_030328.html


Mars Water, Odd Surface Features Tied to Life
By Leonard David
Senior Space Writer

posted: 07:30 am ET
28 March 2003


Mars is one wet and wild world. Scientists are slowly warming up
to the view that trickling amounts of water on the cold, dry
planet may be nourishing Martian biology.

Thanks to spacecraft observations by the Mars Global Surveyor
(MGS), newly formed dark slope streaks on Mars have been
spotted. Emanating from a point source, they widen as they flow
down slope. In some cases, they divide into separate streaks as
they encounter other surface features.

These sharp-edged dark stains always appear on slopes, mostly
inside craters and valleys, but also on small hills. They are
almost always located below Martian sea level - zero elevation.

Over the last few years, cause for the streaks has been chalked
up to the work of winds, or cascading surface materials. These
processes would remove light-colored surface dust to expose
darker bedrock beneath - so the thinking went.

Let it flow

A new view is that liquid flow is the most promising process for
explaining the dark streaks. They appear to indicate currently
flowing water on Mars.

That's the interpretation of Tahirih Motazedian, carrying out
independent undergraduate research at the Department of
Geological Sciences and the University of Oregon.

Images snapped by MGS months apart of a same area on Mars show
that new streaks have formed within a time interval of months.

"It could have happened in an hour or taken all of six months,"
Motazedian said during a presentation of her research findings
at the 34th Lunar and Planetary Science Conference (LPSC), held
March 17-21 in Houston, Texas.

Heat source

Motazedian said that the dark streaks can be found in various
parts of Mars, but are heavily concentrated in the vicinity of
Olympus Mons - a huge volcano on the red planet. Some form of
geothermal activity on Mars -- acting either to melt subsurface
ice or releasing water from liquid aquifers, or a combination of
the two -- is releasing liquid onto the surface and forms the
dark streaks, she said.

It is possible, Motazedian suggested, that geothermal activity,
driven by volcanic heat, is melting subsurface ice. This
melting, in turn, releases a brine that dissolves surrounding
minerals. Furthermore, the brine has a low freezing temperature,
allowing it to flow at the Martian surface. The dissolved
minerals precipitate from solution, leaving behind dark streaks
of rock varnish.

The most exciting thing about dark streaks is that they are
currently forming today, Motazedian told the scientific
gathering. "As I speak to your right now, there are dark streaks
forming on Mars. That's literally true," she said.

Not a dead planet

The sharply-defined end-points of the dark streaks, Motazedian
said, implies that the flows end where their liquid source is
exhausted, having been consumed in a coating of surface dust and
soaking into the ground.

The dark streaks passively overlay other surface features on
Mars without disturbing them or causing erosion. The dark
streaks themselves have neither positive nor negative relief,
Motazedian's research indicates. They appear as if they are
stains on the existing topography, she reported.

The amount of water flowing over the surface to create the
streaks appears to be very, very small, Motazedian said. "It's
pretty much soaking or sublimating (vaporizing) as soon as it
comes down. So it's not forceful enough to erode a path for
itself," she noted.

"Mars is not a dead planet," Motazedian. "So I'm suggesting that
all of you should quit your jobs and investigate dark streaks,"
she told the LPSC gathering.

Streaks of microbial life

Could the dark stains be biological?

David McKay, a NASA space scientist at the Johnson Space Center
in Houston, aired that prospect at the LPSC meeting. He is lead
analyst in the ALH 84001 Mars meteorite detective work that
suggests the rock sports the telltale signs of past life on the
red planet.

McKay offered an alternative view of the dark nature of the
streaks. He speculated that there could be some dormant
microbial life form that is rejuvenated by the water and,
therefore, it is dark when it grows and then slowly dies off
over months or years.

"I'm suggesting this seriously as an explanation. I would like
to see somebody demolish it_but it seems to me that with our
current data we cannot exclude it," McKay said.

Dark dune spots

Also at LPSC, a team of Hungarian Mars researchers, led by Tibor
Ganti and Andras Horvath, presented new work based on
comparative MGS imagery taken over an extended time period. They
see a tie between water in Mars' upper layer and the formation
of what they call dark dune spots, or DDSs.

They have charted the comings and goings, and rebirth of the
DDSs from 1998 to 2002. In their view, the spots point to "some
kind of biological activity of putative Mars surface organisms,
acting on, or in, the material of the dark dunes."

"The massive reappearance of the spots at their original sites
seems to be compatible with our Mars surface organism hypothesis
about the biological origin of dark dune spots," the researchers
said.

Evidence for water on the red planet documented by the Mars
Odyssey spacecraft has bolstered the beliefs of the Hungarian
Mars team.

The prevalence of water seen by Odyssey ranges from the Mars'
South Pole up to 60 degrees South. That coincides with the
regions of the dark dune spots. "From this data we may deduce
that water in some form is relatively abundant in the region of
the dark dune spots," Ganti and Horvath reported at the LPSC
meeting.

Mars on ice

There is no doubt that Mars is on ice, with huge reservoirs of
frozen water hidden just below the planet's surface.

The story of how much ice is sequestered subsurface continues to
grow, said William Boynton of the University of Arizona and
principal investigator for the Mars Odyssey's Gamma Ray
Spectrometer.

Data gleaned by Odyssey has shown tremendous water ice deposits,
Boynton said.

"It really is changing the way we think of how the ice formed,"
Boynton told SPACE.com . The idea that water vapor eked down to
depths deep enough and cold enough to condense out does not seem
to account for the vast amounts of water ice detected, he said.

There's no telling how deep the ice might extend just below
surface on Mars, Boynton said. It could be several hundreds of
feet to well over a mile in depth.

"All of a sudden you're starting to talk about a pretty
significant amount of water," Boynton said. "It looks like the
Viking 2 landing site was actually right on top of this ice. If
its robot arm had dug just a little bit deeper they would have
found it," he said.

As for life being preserved in the ice or still kicking today,
Boynton said that, with reasonable confidence he believes
there's loads of ice on Mars. "If there is something that is
happy living in ice_it is going to be very happy there," he
said.