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As Spirit is presently at the half way point to a real crater in a region where there are many land forms suggesting water, don't give up hope that there are interesting things which may be found by this probe yet. 

Consider that an atmosphere boundary layer containing water vapor only a meter or so thick, if present, would imply that something as low as a crater wall could contain a small localized climate(potentially biosphere) and separate it from the area outside such a barrier.

I'm still holding out hope for an optically detectable surface layer.  After all, with earth's atmosphere having a rule of thumb index of refraction of about 1.003, and vacuum having an index of 1.0000... (by definition), one can still see the reflective mirages over a sun warmed highway on earth caused by boundary conditions which must be changes within that .003 difference.

There are still images from the panorama camera which seem to me to indicate near surface currents in the atmosphere at least similar in magnitude to those observed by pathfinder when it detected the "dust devils" as seen in some of it's enhanced images in NASA's archives.  It doesn't seem to be provable yet, but its very tantalizing to me.

Since I haven't seen the immediate surroundings of Meridiani in the high resolution images from Mars Global Surveyor, Gusev takes it due to the nearby significant crater.  The overhead views suggest that there is really some interesting territory within the crater. 

Also, looking at the images from orbit, does anyone else wonder where the heat shield went after it went end over end into the crater?  The answer to that one should be very interesting.

Some images showing dark streaks also show light streaks down slopes.  Malin, of MSSS.com, says that they are landslides of dust. 

One of the first (other than those seen during the Viking missions) images of these streaks was of the interior of a crater about 6 degrees south of the martian equator.  They made an anaglyph image made up from an image made during the Mars Global Surveyor air braking period and an image made somewhat later.

I became convinced that the streaks were water based when I noticed that there were subtle indications of significant meandering features at the ends of some of the streaks, and also structures, similar to the hot spring deposited canopies found at Sitting Bull Falls in Lincoln National Forest in New Mexico, were noticable at or near their origins high on the crater walls.

Read your referenced article after posting my suggestion. 

They really don't mean "cable splicing", they mean "cable cutting, or severing", and it would probably be done by firing a small explosively driven cutter or explosive bolt.  This is typically a very reliable process.

A further question--Does anyone have lead on how much and what type of processing the current high resolution image has undergone?  Such things as averaging, smoothing, contrast enhancement, and so forth can add or reduce the information contained significantly. 

There is some good information on the Malin (MSSS.com) site's treatment of the Mars Global Surveyor/Mars Orbital Camera images. 

Is there any comparable information for the Spirit and Opportunity images, yet?

Whether the bands visible above the horizon features are actually there or just image features from the camera system is the question.  I still see subtle light bands above the raised features at the horizon in the first high resolution release.

Such a layer possibly enriched in water vapor would explain the higher than expected temperatures being experienced by the probe.

Wonderful initial results by Spirit and all of those involved.

Does anyone else see what appears to be a conformal boundary above the distant features poking above the horizon line in the initial Spirit images?  Could this be indication that there is a near-surface atmosphere layer many of us have not been told about?

dickbill,

Your comments about the presence of peroxides on Mars again bring out my conservative side.  My answer is not based on enough information to be scientific, but I suspect that while there may be some in some places on Mars they probably don't rule the planet to any great extent.  I believe the Levines did their homework, so I would side with them in such matters.

If we allow ourselves to accept the possibilities that water can be exposed to the martian atmosphere, then one, perhaps simplistic, idea would be that carbonic acid could form to some extent, as it's just carbon dioxide disolved in water.  If there are cyanobacteria on some submerged surfaces, then they would break down the CO2, utilize the carbon and give off the O2.  There might be regions near such surfaces where the water is saturated with oxygen by this means, similar to some of the ice capped lakes of the artic regions of earth.  The higher the local pressure, the higher the possible oxygen content such that if the pressure were released, and/or such oxygen saturated water were brought closer to the surface, free O2 would bubble out of it. 

The possibilities for obtaining oxygen for a manned expedition in this way should be obvious.  A pipe run down into such a region of O2 saturated water could perhaps be used to pump such fluid near the surface where it would fizz in the decreased pressure.  Once started it could concievably even be self pumping as long as the sun and photosynthesis could replenish the O2.  Of course one wouldn't want to tap into a reservoir of H2S without the means of coping with it.

dickbill,

You are certainly correct that the transfer of water (in whatever state) from Mars' surface to the boundary where the temperature is low enough for it to condense out as snow and fall back to the surface can be complex when looked at in great detail. 

Lets back off a bit and take look at what we know about the properties of water.  (I suggest looking at Dr. Gilbert Levine and his son Ron's 1998 SPIE paper about the plausability of the Viking labeled release experiment having detected life on Mars in the '70's. They have good treatment of water and its triple point.) 

Here goes my stab at explaining water and it's properties:  Below 273 degrees Kelvin = 32 degrees Farennheit = 0 degrees Celsius, water's most stable state is as a solid, ice.  With a temperature high enough above absolute zero (0 degrees Kelvin), there is some probability that some water molecules will obtain enough energy to free themselves from the solid ice surface as individual water molecules comprising a gas.  This process of becoming a gas is called sublimation and it takes energy.  The number of calories per gram of water required to do this is about 638 under very low pressure 

This total can be broken down, in nice round numbers, to 88 calories per gram for water to go from 273 degree Kelvin ice to 273 degree Kelvin liquid water, and 550, plus a little additional, calories per gram for the liquid water to become the gas we call water vapor at 273.16 degrees Kelvin we call water's triple point.

If the water has a vapor pressure it'll evaporate, right?  The answer is of course yes, but it won't get away completely before exchanging some of it's energy through collisions with the much lower energy atmosphere just above the surface of Mars, latching onto other water molecules which have also been sapped of energy by the cold atmospheric gas and eventually falling back to the surface as solid particles, or sticking to higher surface points of the land as frost crystals which likely have some probability of subliming back into the cycle, or some seasonal likelihood of warming to become liquid and flowing or seeping back downward. 

Each change of state requires an energy transfer,--up to become more fluid, --and down to become less fluid.  Notice that the temperature of our gram of water did not have to change, and that the ice can go directly to vapor, but we still have to pay the about 638 calorie price (toll) in energy added to get a gram of free-single-water-molecule gas from solid state water.  We have to lose that same energy to get back to ice.

At water's triple point, we don't get much water vapor but all three states(or phases) of water can co-exist at equilibrium at almost exactly Mars' surface atmospheric pressure as recorded at the Pathfinder and Viking I landing sites.  I personally suspect that the 6.3 millibar typical measured atmospheric pressure at those locations is not a coincidental number as that is the vapor pressure of water at it's triple point.

I've not mentioned things like super cooled liquid water or other metastable states which can exist simply because I'm mostly considering equilibrium systems.

While I'm at it, I think we should consider the possibility that the "dust devils" on Mars might be being powered by the huge energy stored in rising columns of surface water vapor carrying 638 calories per gram just waiting to be released as it changes to a solid.  Perhaps their opaque appearance is due to the presence of ice crystals that are being formed, or which are being lofted from the surface by the rotating winds only to serve as nucleation sites for the water vapor.  Solid particles have higher unit mass and would be thrown out to a kind of 'event horizon' surface allowing the lower unit mass, lower pressure, vapor core to reach much higher altitudes than would be possible without the rotational motion.

If anyone made it this far, its wordy, but please forgive me.

By the way, the silica you see as a trace ingredient in many powdered food and drink mixes (to keep them flowing as a powdered material and prevent clumping) is probably the product of burning silane and is called fumed silica.  The particles are very small and light\fluffy. 

Trivia, I know, but for what it's worth...

Thanks,

This article is one of those derived from the press releases I was referring to two or three posts back and brought up earlier in this topic.

Watch out for the carbonates story!  If you read it more carefully, at least the versions I've seen, there is a statement that says (perhaps paraphrasing some) "down to a scale of 3 to 5 kilometers". 

I live in Missouri, where one of the asteroid impact movies was going to place a sizable percentage of the population of the United States for protection through the impact event in underground limestone mine cavities near Kansas City.  There is a lot of limestone, both calcium carbonate and calcium magnesium carbonate, here. 

I truely wonder if the instruments would detect carbonates here, from the ~400 kilometer altitude and near the nadir, if the lateral resolution for detection is as poor as 3 kilometers.  Much of the limestone is just below a surface covering of dirt (regolith?) and is only exposed along rock cuts through hills along highways and natural erosion channels along sizable rivers, both of which produce approximately vertical walls revealing only one dimension which might rarely be over 3 kilometers.  The other locations yielding only one dimension are concrete highways and road surfaces covered with crushed limestone, both of which I don't expect to find on Mars.