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ZL2VAL > ROVERS 01.03.04 11:19l 212 Lines 9022 Bytes #999 (0) @ WW
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Subj: NASA tight about Martian water
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Mars: A Water World? Evidence Mounts, But Scientists Remain Tight-Lipped
By Leonard David
Senior Space Writer
posted: 01:00 pm ET
29 February 2004
PASADENA, California -- Evidence that suggests Mars was once a
water-rich world is mounting as scientists scrutinize data from the Mars
Exploration rover, Opportunity, busily at work in a small crater at
Meridiani Planum. That information may well be leading to a biological
bombshell of a finding that the red planet has been, and could well be
now, an extraterrestrial home for life.
There is a palpable buzz here at the Jet Propulsion Laboratory (JPL) in
Pasadena, California that something wonderful is about to happen in the
exploration of Mars.
There is no doubt that the Opportunity Mars rover is relaying a mother
lode of geological data. Using an array of tools carried by the golf
cart-sized robot -- from spectrometers, a rock grinder, cameras and
powerful microscopic imager -- scientists are carefully piecing together
a compelling historical portrait of a wet and wild world.
Where Opportunity now roves, some scientists here suggest, could have
been underneath a huge ocean or lake. But what has truly been uncovered
by the robot at Meridiani Planum is under judicious and tight-lipped
review.
Those findings and their implications are headed for a major press
conference, rumored to occur early next week -- but given unanimity
among rover scientists and agreement on how and who should unveil the
dramatic findings. Turns out, even on Mars, a political and ego outcrop
hangs over science.
Scientific bulls-eye
It is clear that Opportunity's Earth-to-Mars hole in one -- bouncing
into a small crater complete with rock outcrop -- has also proven to be
a scientific bulls-eye. The robot is wheeling about the crater that is
some 70 feet (22 meters) across and 10 feet (3 meters) deep.
It is also apparent that there is a backlog of scientific measurements
that Mars rover scientists working Opportunity have pocketed and kept
close to their lab coats.
For one, the rover found the site laden with hematite -- a mineral that
typically, but not always -- forms in the presence of water. Then there
are the puzzling spherules found in the soil and embedded in rock. They
too might be water-related, but also could be produced by the actions of
a meteor impact or a spewing volcano.
A few spheres have been sliced in half and their insides imaged. Patches
of these spherules, or "berries" as some call them, have undergone
spectrometer exam to discern their mineral and chemistry makeup.
Close-up photos of soil and rock have also shown thread-like features
and even an oddly shaped object that looks like Rotini pasta.
Brew of dissolved salts
There is speculation that the soil underneath the wheels of both Spirit
and Opportunity rovers contains small amounts of water mixed with salt
in a brine. That brew of dissolved salts keeps the mixture well below
the freezing point of pure water, permitting it to exist in liquid form.
Opportunity has revisited select spots in the outcrop, drawn there, in
part, to look for cross-beds -- sedimentary deposits that are formed in
beach, river and sand-dune environments. Using its Rock Abrasion Tool
(RAT), the rover has carried out several cleaning and grinding sessions
on exposed rock outcrop.
Cross-beds are patterns of curving lines or traces found within the
strata of sandstone and other sedimentary rocks. Cross-bedding indicates
the general direction and force of the wind or water that originally
laid down the sediments.
Right around the corner
Opportunity's research is a "work in progress", said Ray Arvidson,
deputy principal investigator for the Mars Exploration Rover (MER)
project from Washington University in St. Louis. Data is being gathered
to present "a coherent story", he said during a press briefing last
Thursday.
"That story is right around the corner," Arvidson told SPACE.com . "But
we need to finish this work in progress, finish the set of experiments,
get the data down from the spacecraft, processed and analyzed. Then I
think that the story will be known," he said.
Arvidson said multiple working hypotheses are still at play. Water is
involved, but only on some of the hypotheses. Until coordinated
experiments on the outcrop are completed, what the right hypothesis is
remains unknown, he added.
Severing the umbilical cord
Mars exploration using the rovers has allowed on-the-spot "discovery
driven science", said MER Deputy Project Scientist Albert Haldeman. He
likened the Mars robot work now underway to deep ocean research using
remotely operated submersibles.
"It turns out that the best way to explore rocks [on Mars] is go look at
craters. Mobility buys us the ability to do that. It was the right fit
for looking at rocks," Haldeman told SPACE.com . "The discovery from the
Microscopic Imager and seeing those spherules?and finding a larger
population of spherules and seeing them in the rocks and the
outcrop?that progression of discovery influences our thinking."
Haldeman said the next step will be severing the umbilical cord between
Opportunity and the crater it's exploring. The robot would wheel itself
out of that site and onto the expansive terrain of Meridiani Planum.
"That umbilical cord?that's hard to break. It's more than even just a
tension within the science team," Haldeman said.
Tantalizing hints
Scientists are carefully analyzing the rock data gleaned by the
Opportunity rover. "We really want to understand that we've got those
figured out right," Haldeman said. Up to now they have offered some
"tantalizing hints", he said, that speak to a possible relationship with
water.
Piecing together the story of what Opportunity has found involves great
care and deliberation, Haldeman said, based on a wide-range of
viewpoints and levels of expertise. "We want to be cautious," he explained.
More to the point, the science output from Mars must withstand scrutiny
by experts outside the rover investigation teams.
"There are lots of geologists out there who are looking at these
pictures and they are starting to drool," Haldeman said. "The American
taxpayer that spent $800 million on this deserves a thorough analysis,"
Haldeman said.
Slippery slope leading to life
One scientist eagerly awaiting the news from Mars, particularly from
Opportunity, is Gilbert Levin. He is Chairman of the Board and Executive
Officer for Science of Spherix Incorporated in Beltsville, Maryland.
Levin is a former Viking Mars lander investigator. He has long argued
that his 1976 Viking Labeled Release (LR) life detection experiment
found living microorganisms
<http://www.space.com/news/spacehistory/viking_life_010728-1.html> in
the soil of Mars.
In 1997, Levin reported that simple laws of physics require water to
occur as a liquid on the surface of Mars. Subsequent experiments and
research have bolstered this view, he said, and reaffirms his Viking LR
data regarding microbial life on Mars.
Levin detailed his Mars views in a SPACE.com phone interview and via email.
"It's hard to image why such bullet-proof evidence was denied for such a
long time, and why those so vigorously denying it never did so by
meeting the science, but merely by brushing it away," Levin said.
"Of course, now that it must be acknowledged by all that there is liquid
water on the surface of Mars," Levin added, "this starts those denying
the validity of the Mars LR data down the slippery slope leading to life."
Mars mud
Levin points to Opportunity imagery that offers conclusive proof of
standing liquid water and running water on a cold Mars.
Other images show the rover tracks clearly are being made in "mud", with
water being pressed out of that material, Levin said. "That water
promptly freezes and you can see reflecting ice. That's clearly ice. It
could be nothing else," he said, "and the source is the water that came
out of the mud."
As for the spherical objects found at the Opportunity site, Levin has a
thought.
"I wonder on Mars if it can rain upwards," he said. The idea is that
subsurface water comes up through the soils and then freezes when it
gets to the surface.
"Maybe these little spherules form just like raindrops form up above,"
Levin explained.
Levin said that brine on Mars is a code word for liquid water. He senses
that great care is being taken by rover scientists because the liquid
water issue starts the road to life.
"That's the monument that they are afraid to erect without real due
process," Levin concluded.
=========================
73 de Alan, (Sysop ZL2AB).
AX25:ZL2VAL@ZL2AB.#46.NZL.OC
APRS:!3903.34S/17406.45E]
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Message timed: 22:09 on 2004-Mar-01 (NZT)
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Points to ponder
~~~~~~~~~~~~~~~~
Marriage
~~~~~~~~
Getting married is very much like going to a restaurant with friends.
You order what you want, then when you see what the other person has,
you wish you had ordered that
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