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I think the white areas on the rocks are just areas where the reflectance of the rock is oversaturating the ccd at the exposure setting used for the snapshot. Perhaps the sun is reflecting off a smooth area of the rock. The limit of the ccd just records areas above this limit as all white rather than shaded gradation since it cant differentiate the data when it overflows the ccd. just like the http://www.lyle.org/mars/imagery/1F1354 … tml]images showing some rover metal, it cuts out as white since it need to get the right contrast for the rest of the image. If the ccd had some extra dynamic range (btw i thought they could design a ccd that just does photon counts, eliminating this "overflow" limitation, the resultant image data could then be optimized to show an infinite dynamic range), then these areas would have some gradation and not just get pegged to solid white. Therefore, if the exposure for this snapshot were lessened a bit, we'd see these white areas replaced by some gradation rather than the cut-off limit going all white in a block. however, the rest of the image would in turn be darker. sorry for the long winded rambling but i think thats all it is.

Olivine is a bit more complicated http://mineral.galleries.com/minerals/s … ne.htm](Mg, Fe)2SiO4, Magnesium Iron Silicate (not that i know much about geology or what the implications of this are, i just got curious and looked it up).

And thanks for bringing this up, it hadnt even occurred to me that there might be the possibility of finding mineral veins in Mars rocks, i guess i just got used to seeing boring basalts, and so far it looks like there havent been any veins, but if quatz is a no-go maybe well see some other type of minerals or crystal inclusions if there is some exposed bedrock in the hills?

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So Spirit is "fishing for dust devils":http://www.msnbc.msn.com/id/4790474/]article: 

And according to http://www.gsfc.nasa.gov/topstory/2004/ … .html]this interesting article: 

...not sure if this means that theres more voltage getting grounded into the soil or not, but if electricity can be an impetus on the coalescence or formation of organic molecules, might this perhaps be supportive of processes leading to life? but is the 'zap' strong enough? note the image depicts an http://www.gsfc.nasa.gov/gsfc/spacesci/ … electrical discharge glow. So we've got water and lots of minerals in the soil, UV and radiation probably creating all sorts of radicals at the surface and some static electrical stuff going on as well, sounds like if the soup was wet enough something might eventually happen with all those ingredients...

The leading theory of the gullies posits that there is ice cover in areas adjacent to gullies that get less sunlight. Future gullies will be created and unearthed (er, unmarsed) as this ice cover melts (due to the sun angle shifting due to Mars' pole procession). The problem with currently making a definitive identification of the supposed underlying ice is that it is under a cover of dust which, to the orbital instruments, makes it look just like the adjacent areas (although, i thought Oddyssey could spot such deposits maybe its resolution isnt sharp enough to differentiate these areas from the surrounding terrain?). This indirect evidence (the smooth terrain and absence of gullies) is implies the ice cover really is still there to this day in these gulley-adjacent areas.

That said, it seems likely that there are large deposits of dust-covered ice in the center of certain craters.

Actually, since Diemos is not only much smaller but is also much further away than Phobos (as viewed from surface of Mars), it appears that much more tiny against the face of the sun. To get the actual objective relative comparison, you'd be better served by http://solarviews.com/raw/ast/gaspra5.jpg]this image comparing asteroid 951 Gaspra (top) compared with Deimos (lower left) and Phobos (lower right).

It would indeed be interesting to get a view of Phobos during the daytime. I hope they try, my impression is that the pancam could probably get a decent shot of it even through the dust. Better yet, i hope they try to get a shot the eclipse shadow on the ground when Spirit is on top of the hills. That might be a high enough vantage point to get a good oblate view of the shadow moving across the surrounding plains.

Here's some http://photojournal.jpl.nasa.gov/jpeg/P … .jpg]great closeups of Phobos. If you could stand on Mars and watch Phobos passing overhead, you would notice that this moon appears to be only about half the size of what Earth's Moon looks like when viewed from the ground. In addition, the Sun would seem to have shrunk to about 2/3 (or nearly 1/2) of its size as seen from Earth. Phobos, having an orbital period of slightly less than 8 hours, would appear to rise in the west and set in the east only five and a half hours later.

In trying to come up with an explanation for Bounce, here's what I think is the most likely scenario: Bounce was gouged from far away hills by a glacier then carried and dropped off here by an iceberg eons ago, it was probably buried by some sediments and has since been exhumed by wind action. It will be interesting to see how many other basalt rocks are in the region.

The bedrock here is somewhat soft and erodes quickly. The fine light dust you see collected in places like the center of Fram crater as well as the lee side and other parts of of Eagle crater blows around easily and is generally removed from the area over time leaving everything else on the top of the soil. Heres a [http://www.lyle.org/mars/imagery/1M1330 … 1.JPG.html]closeup of this dust as seen at the [http://www.lyle.org/mars/imagery/1P1329 … 1.JPG.html]little ripple field in the [http://www.lyle.org/mars/imagery/1F1329 … 1.JPG.html]center of Eagle crater.

Underneath all the sand and blueberries, which have created an erosion-resistant cover for the soil and bedrock beneath, youll find this sedimentary bedrock going down at least a few hundred feet (if the appearance of other nearby craters form orbit is any guide). But if we do find that some of the craters punched deep enough to expose basaltic layers, then Bounce could be ejecta. Thats my impression anyway.

i guess it all depends upon whether or not the subsurface temperatures and mineral content of the water are high enough to allow it to exist in liquid form...
...but during the regular climate shifts due to procession, i'd expect  the water to flow to the surface and persist for a while, insulated by a cover of ice.
...however, if the ground water supply isnt being replenished in some way, then over the millions of years the water table would slowly drop lower and lower as it slowly leaks to the surface through these episodes and collects at the poles or leaks off to space, leaving the top of the water table at a point below the reach of these warming episodes...

:hm: Shells... makes sense, Carl Sagan surprises me again! This brings me back to [http://www.lyle.org/mars/imagery/1M1289 … 1.JPG.html]the first MI image of the soil from Opportunity, shows a small object a tiny bit to the upper right of the center of the image. My first impression back then was "looks strikingly like a snail shell, but no, it couldnt be..." since it has a certain degree of radial symmetry of divets, much like a sea-snail shell does, there also happens to be another similarly-sized object just above and to the right of it that also has a similarly interesting symmetry of indentations. My instinct was to discount this as cooincidence and figure that these are just vessicle-riddled tectites or something. But if there was macroscopic multicellular surface life on Mars way back, then its not at all too much of a stretch, but perhaps may be the rule, that it would adapt in later stages, as the atmospheric protection dwindled, to move to shelled forms such as this... if so, then there would (should?) be a larger poulation of these lying around in the sand but i havent seen any more (or maybe i havent looked hard enough) i'd expect all of them to be long-dead, though!

Great picture! It would seem that the dark stuff is indeed Blueberries, but i dont think the blueberries are actually getting moved around. My impression is that instead, they just happen to be getting exhumed in this particular pattern: As the winds blow in a certain pattern around the terrain feratures, the area of most wind gets exhumed leaving apparent "windtails" of blueberries leeward of the terrain features.

Complicating this whole issue is how strange the Sand/Dust transport process is on Mars, as you can see in
[http://www.lyle.org/mars/imagery/1N1345 … 1.JPG.html]images like this. Here i would expect features to get filled in by dust/sand drifts, but it seem that the operating principle is to exhume divets and bdrock features like "home plate" which lies at the bottom of a small divet of sand. i'd expect homeplate to tend to get buried but it isnt, some process keeps it clear. it makes me wonder how long this feature has been like this, maybe not much accumulation occurs and mostly whats going on is exhumation so that the topography, aside from the little white dust drifts, is pretty much the topography it was hundreds of millions of years ago and only a small removal of several feet has occurred by wind action leaving the heavy blueberries and sand grains at the top and taking away all the bedrock (which erodes as a fine light powder and quickly blows away), leaving this pattern of dark tracks.

In Errorist's theory, the Devil's Advocate might consider that we dont necessarily have to be talking about rocky debris as the source of the moon impactor, cometary bodies composed mostly of water and other volatile compounds would suffice and wouldnt necessarily leave much evidence, and there should have been lots of them around at the time these events occurred... this type of process probably happened to all the planets and moons, although usually a planet's moon wasnt destroyed. An outside planetary body having just the right size, impact angle and speed, explains why Earth even has a moon at all, and which is composed of its own mantle crust. By taking crust from the Earths surface and putting it overhead as the moon, this freed up the Earths crust to float in continents that move around more readily and is one explanation of why plate tectonics is so active on Earth and isnt locked up like on venus or dead like on Mars. Thus we have land life on Earth because plate techtonics can keep building landmasses as fast as erosion takes them away, otherwise the Earth would be a waterworld swept by massive perennial globe-girdling storms that would destroy any reef building systems. Hotspot volcanoes dont last long enough to build islands that can last long enough to allow land evolution to progress very long. intelligence might develop in the oceans but you need things like trees, stable dry climates and hands to develop tools, but i digress, it seems unlikely that Mars would even have a sizeable moon at all, unless the same unlikely thing happened and also happeneed to get destryoed by an equally unlikely scenario.

Errorist's theory has some comparisons with Haogland's [http://www.enterprisemission.com/tides.php]Mars Tidal Model, which puts forth an explanation for the disparity between the Martian highlands and lowlands and the current oblique equatorial orientation of these features. Its a highly detailed and thought provoking theory, but leaves as much unexplained as it tries to explain, especially the exploding planetary body which conveniently is "explained" by his hyperdimensional physics stuff.

Regardless, isnt it a heck of a lot much more likely that the mountains were formed by volcanism or plate tectonics (as short-lived as they were) anyway??? There shoudl have been some geysers, and i hope we find some evidence of them but they arent necessary to explain the mountains, do these mountains have certain features that defy other explantions? a mark of a good theory is that it explains what other theories cannot while at the same time doesnt leave open any holes that others theories fill...

yeah, at least a thousand feet of sediments... perhaps much more... but its hard to say if the bulk of it was depositied slowly over the eons (think lots of potential for life) or if most of it was lain down in a few catastrophic events, im not sure if there are a lot of geological signs of catsrophic events near Meridiani as far as im aware of... but then again catastrophic events would carry a lot of boulders so it would probably look more like gusev, so perhaps it is necessarily a very slow deposition... anyone have a different view on this?

the article also states:
"In addition to the scheduled end of the extended mission in mid-September, Mars will be in solar conjunction around September 13, a period when the sun lies between Earth and the red planet. That positioning will block communications with both rovers for at least a week to 10 days, mission scientists said."
couldnt they periodically just relay the data through some other mission that isnt near earth but is still close enough to get a signal such as Ulysses (that has a solar polar orbit i think) or maybe the signal, even if relayed through oddyssey isnt strong enough for anything but earth-based radio arrays to pick up...?

So if multicellular life, intelligence and other such evolutionary-rut side-stepping advantages tend to always be propogated by latent contingencies within the mutation flux of the genotype (they just have to wait for the right conditions to flourish), then the intermittent changes along the way should crop up with perhaps somewhat rapid stochastic frequency, yet only to be repeatedly thwarted by being diluted in large genepools or nullified by an unfavorable selective environement. Therefore there is probably no good evolutionary reason to rule out the possibility of multicellular life on Mars very early on in its history. It may be unlikely, but if the Mars environment coupled with small genepools allowed such changes to propogate, and conditions selected for it, then evolution on Mars could have moved along very quickly indeed. So its really not entirely out of the question that there might be macroscopic fossils on Mars... (i was tending to assume a sort of slow progressive ascent of complexity andMars just didnt have nearly enough "quality time" for multicellular life to ever come about, not that i expect it has, but im crossing my fingers)

So the environment changes, populations plummet thus shrinking the genepool and making any new mutations statistically relevant, that when favorable, change the genotype very rapidly.
...do adaptive stresses or other forces somehow increase the actual rate or quality of the mutations themselves?
...or is it merely that the same old normal (or almost normal) mutations are much more influential due to their newfound statistical relevance?
...or maybe the mutations get factored into a feedback cycle where the diversity of the mutations feeds into the increased frequency of them, and this syngergistically peaks both the change rate and diversity value higher?