I've a lot of respect for Gilbert Levin and his work, but I wonder if he might be pushing things a bit too far with his latest claims about life on Mars.

Space.com article here

I know, I know, it's hard to restrain oneself when faced with the wealth of data coming back from Mars, but these experiments are not designed to make the determination as to whether what we are seeing is, in fact, water. And it's a leap between water and life...

He's not being heard, except by the woo-woo fringe now.

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LUKE SUM IPSE PATREM TE
Luke, I am your father.

If there were water, couldn't the rovers detect it?

__________________
Everything I need to know I learned through Googling.

Only if it were in their vicinity. I don't think anyone is suggesting it is everywhere.

It is no different than what he has always been saying. I don't see why you would say he going to far *now*, as oppposed to before.

This article shows Mars and extremophile expert Penny Boston is taking seriously the idea that life currently exists on Mars:

Posted 8/3/2004 4:56 AM
Researchers: Water could mean Mars hills were alive
The Associated Press
"These hills might date back to some of the earliest history on Mars," said Larry Crumpler, a Mars Exploration Rover team member and curator at the New Mexico Museum of Natural History and Science. "It looks like a river channel might have flowed through there. In fact, the case is building that lots of standing water — streams, maybe ponds, existed in the planet's history."
"Water is important to Crumpler and fellow scientists because it indicates life might have evolved on the planet.
"If so, it was most likely microscopic. But still, the idea is thrilling, said Penny Boston, a planetary scientist and Mars expert at New Mexico Tech in Socorro.
"Is there a chance that life still exists on Mars? I sure hope so," Boston said.
"With the new evidence of water, she thinks there is about a one-in-three chance that life still exists — based on estimates that are part faith and supposition and part science. "If you asked me that 10 years ago, though, I would have said one in 100," she added."
http://www.usatoday.com/tech/news/20...rs-hills_x.htm

More on Dr. Boston's research:

Life in the Extremes: An Interview With Dr. Penelope Boston.
http://www.ibiblio.org/astrobiology/...ge=interview09



Bob Clark

Levin seems to be suggesting that the rovers are driving across moist soil. You'd think one of the instruments like the mini-TES could detect water.

__________________
Everything I need to know I learned through Googling.

Not to mention that if there was anything approaching surface water or frost, you'd better believe NASA would be holding a press conference (especially with their budget under review as we speak). I'd say NASA was holding back until they were 100% sure, but Levin was making these claims months ago.

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Do try not to take me too seriously.

See... I don't think that they can discern that. I thought that the question had been raised earlier in Opportunity's mission when the white substance was dredged up by one of the trenching exercises.

IIRC the trenches were Mossbauered (is that even a word?) and mini-tessed and signatures of salts were discovered. The question was raised as to whether it was brine or not and the response was (I thought) that there was no way of telling with the equipment.

Perhpas I'm wrong in that.

True, the pictures do raise some interesting questions - frost from mositure released by the digging, RATting and pressure. But to make the conjecture that there's water that close is unsupported and perhaps unsupportable by the scientific equipment on board. Or am I wrong?

For the record, I'm inclined to believe that Levin's experiments may have discovered life. But until we have a probe on site with sophisticated enough experiments, I'm going to have to be a doubting Thomas.

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Me dilectissima! Farrago thunni!
My favourite! Tuna-noodle casserole!

The Mini TES is fully capable of detecting frost or any free water or brine on the surface of Mars. Free water would appear on the TES spectra as a peak at 1640cm-1. The paper by Gilbert Levin is so badly flawed that it would be laughable if it were not so sad. The sad part is that some of the general public are taking it seriously.

It totally misses the point that water is unstable on the Martian surface. The following peer reviewed paper discusses the question of the stability of water on a much more rigorous basis:

http://www.agu.org/pubs/pip/2004JE002367.pdf

"While the total surface pressure on Mars is near 610kPa, the triple point vapor pressure is defined in terms of the water vapor partial pressure and thus contraray to popular perception, liquid water is far from stable on Mars) in fact, it is incorrect to state that the Martian environment is close to the triple point for water - It is not)."

It then goes on to explain how ephemeral transient monofilms of water may be possible under very special conditions on the Martian surface, for example under a protective ice sheet capable of trapping vapour and allowing the pressure to build.

All of these cases are transient, and depend on recharge of water.

__________________
Reality is merely an illusion, albeit a very persistent one. - Albert Einstein

7 months is a looong time. I wondered who'd taken my user name.

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Nunc dimittis
Let thy servant depart in peace...

The paper seems to be talking about pure water (correct me if I'm wrong), but what about brine?

__________________
Everything I need to know I learned through Googling.

Now Opportunity HAS detected surface frost at least on the landers.

Next question?


Bob Clark

Levin is aware that liquid water on the surface would eventually evaporate. His point is that microorganisms could survive on liquid water available for only minutes in a day, and then go into a long suspended date during the period when conditions are too cold.
Experiments have shown that liquid water can exist from minutes to hours on the Martian surface:

==============================*=======
Office of University Relations
University of Arkansas


CONTACT:
Derek Sears
Professor, chemistry and biochemistry, Fulbright College;
Director, Arkansas-Oklahoma Center for Space and Planetary Sciences
(479) 575-5204, dse...@uark.edu


Melissa Blouin
Science and research communications manager
(479) 575-5555, blo...@uark.edu


EMBARGOED FOR RELEASE AT 2 P.M. WEDNESDAY, SEPTEMBER 3, 2003


SURFACE WATER POSSIBLE UNDER MARS-LIKE CONDITIONS


FAYETTEVILLE, Ark. -- A team of researchers from the University of
Arkansas has measured water evaporation rates under Mars-like
conditions, and their findings favor the presence of surface water on
the planet. Water on the planet's surface makes the existence of past
or present life on Mars a little more likely, according to the group.
Derek Sears, director of the Arkansas-Oklahoma Center for Space and
Planetary Sciences, and his colleagues graduate student Shauntae Moore
and technician Mikhail Kareev reported their initial findings at the
fall 2003 meeting of the Division of Planetary Sciences of the AAS.
The researchers have brought on-line a large planetary environmental
chamber in which temperature, pressure, atmosphere, sunlight and soil
conditions can be reproduced. Sears and his colleagues use the chamber
to investigate the persistence of water under a range of physical
environments and to study its evaporation.
For their first experiments, reported at the DPS meeting, the group
chose to measure one of the most important properties of water on a
planetary surface, the rate at which it evaporates.
"Physicists have long argued that Mars is currently a sterile desert,
completely unsuited to life," Sears said. "This conclusion is based on
their belief that water would evaporate very quickly, as soon as it
appeared on the surface."
The University of Arkansas group examined the effect of Mars'
atmospheric conditions -- temperature and wind -- on the evaporation
rate. The movement of the atmosphere close to the surface is a crucial
factor in the survival of water on Mars. Water evaporates more slowly
when evaporated molecules build up over the water's surface, but wind
sweeps away evaporated molecules, allowing more water molecules to
escape the surface and increasing evaporation rates.
"These findings suggest that even under worst case scenarios, where
wind is maximizing evaporation, evaporation rates on Mars are quite
low," Sears said. This implies that surface water could indeed exist,
or have existed recently, under the given conditions on Mars.
In addition to the evaporation experiments, the group examines the
ways in which water-ice behaves when frozen at depth and how it reacts
when covered with layers of frost or dust. They also explore how ice
behaves when exposed on the surface, and whether it can exist in a
transient liquid phase that could harbor life.
The subtle balance between the input of heat from the Sun and
subsurface sources and the strength of the surface atmospheric motions
determines the fate of the water; whether it remains as ice, becomes
liquid, and if so how long it remains as a liquid, or how quickly it
evaporates.
"The environmental chamber will enable us to gain new insights into
the behavior of water on Mars and reduce much of the speculation on
this topic," said Barney Farmer, principal investigator for the
atmospheric water vapor mapping experiment during the Viking missions
and a member of the Arkansas research group.


EDITORS NOTE: Dr. Sears will be at the Doubletree Monterey during the
meeting. The number there is (831) 649-4511.
==============================*=======


Here is an abstract to this month's LPSC discussing this:


STABILITY OF WATER AND GULLY FORMATION ON MARS.
Derek Sears1,2, Larry Roe1,3, and Shauntae Moore1,2.
1W. M. Keck Laboratory for Space Simulation, Arkansas Center for Space and Planetary Sciences, University of Arkansas, Fayetteville, AR 72701, 2Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701,
3Department of Mechanical Engineering, University of Arkansas, Fayetteville, AR 72701.
Lunar and Planetary Science XXXVI (2005) 1496.pdf
"We measured evaporation rates at 7 mb under
conditions much closer to martian than previous
work and eight determinations yielded a value of
1.04 ± 0.14 mm/h [7]."
http://www.lpi.usra.edu/meetings/lpsc2005/pdf/1496.pdf


Bob Clark

Read it in more detail. Brines are also discussed.

__________________
Reality is merely an illusion, albeit a very persistent one. - Albert Einstein

I have no problem with the fact that ephemeral liquid water can theoretically exist on Mars for extremely brief periods. That was also the conclusion of the paper I cited. Levin jumps one stage further and claims that not only is water possible, but that it can be proven to exist from the Pancam data. Let's stick to my original assertion that the paper is seriously flawed without bringing in other papers.

In particular, I am referring to this paper:

http://mars.spherix.com/5555-14.PDF

Specifically it is using nonsensical data to 'prove' that we are seeing mud in some of the images from the Meridiani landing site.

His sole argument is that the Absorption coefficient of water increases with increasing wavelength over the range of the Pancams.

"Figure 8b taken at 753nm shows darker darks than Figure 8a taken at 535nm............but the increasing darkness indicating water, is obvious:"

The source of the data is from raw images taken from the NASA site. Not only is this uncorrected for exposure, but the assertion is made that because it gets darker with increasing wavelength, it is 'obviously water'.

As has been pointed out elsewhere, there are a number of substances commonly found on Mars that exhibit a similar spectrum over this range.

That is by no means the only flaw in the paper, but let's concentrate on that one for now.

"Levin is aware that liquid water on the surface would eventually evaporate. "

I'm not sure exactly what Levin is aware of, but Bob, how can you honestly defend such a flawed paper? I'm sure that the reputable researchers that you cited would not thank you for the association.

__________________
Reality is merely an illusion, albeit a very persistent one. - Albert Einstein

I agree that surface frost has been detected on the solar panel of Opportunity, and there is a chance that it could have been present on the surface. However, how do you get from short lived frost deposits which subliminate during the earliest part of a mid-winter's Sol, to mud ?

That frost would have been detectable using the Mini TES instrument if it were activated during this period, however that instrument is not normally used until later in the Sol.

Free water in the form of mud or brine would be detectable using the Mini TES. If this had been detected, NASA would have been the first to announce it, just as they announced the frost on the panels.

__________________
Reality is merely an illusion, albeit a very persistent one. - Albert Einstein

You were referring to more than just that paper. You were making the blanket contention that liquid water wouldn't exist on Mars. Actual experiments wouldn't support that claim.
I can tell you that in the papers themselves where he discusses his labeled release experiment he specifially mentions that liquid water would be temporary but he says that is all microorganisms would need to survive.
The reputable researchers I cited would have no problem with Levin's contention that liquid water could exist for short times on Mars, since that is what their research shows.
I did a search within the Levin article you mentioned:

Interpretation of new results from Mars with respect to life.
http://mars.spherix.com/5555-14.PDF

and no where does he use the word *prove* in regards to liquid water at the MER landing sites. The only time he uses the word *prove* is in relation to his contention that his experiment on the Viking mission prove life on Mars.
I believe what Levin is saying in regard to liquid water using the PANCAM images is that they are *consistent with* liquid water.


Bob Clark

...and on the basis on the information presented, he can't even say that in any sort of meaningful way. The data has not even been corrected for exposure for the various filters.

Even looking at the spectrum over this narrow range, it is also consistent with olivine and/or hydrated salts.

"and no where does he use the word *prove* in regards to liquid water at the MER landing sites."

Perhaps not, but to say, "but the increasing darkness indicating water, is obvious" is getting pretty close. It goes much further than saying that it's merely consistent with liquid water.


What I'm saying is that the paper rings alarm bells all over the place. If it is consistent with anything, it is consistent with very little knowledge of scientific principles. And a little knowledge is a dangerous thing.

__________________
Reality is merely an illusion, albeit a very persistent one. - Albert Einstein