The key to the paradox is the famous fact that "viscosity is independent of pressure". The usual heuristic explanation is based on the elementary kinetic theory of gases. Viscosity is due to momentum transfer across streamlines. The crude analogy is of a food fight between passing trains. The transfer of material will speed up the slower train and slow down the faster train. In a thinner gas, a given volume of gas will have less momentum transfer from a nearby volume, but it will receive momentum transfer from a greater distance, due to the greater mean free path of the gas molecules in the thinner gas. Anyway, this means that very fine particles can be taken aloft in a thin atmosphere just as easily as in a thick atmosphere. Note this only applies to fine particles. Gum wrappers would not blow around in a Martian wind, because the atmosphere doesn't have enough mass density, and in this case our intuition about thinner and thicker air is correct.
Re the nature of the "watery" looking material, I think it is dust which has blown into the cracks formed from the original impact. The brighter dust at the bottom is sandy material which has eroded from the surface and come to rest there. I think the horizontal striations are the original layers of the Martian regolith built up by dust storms over millions of years, and the surface we're looking at was scoured and compressed by the ejection of material at impact. Note that the crater is much larger than the impacting body, so conditions that formed this surface are not the most extreme, being at the outer boundary of the impact's effects. I think the compression of the surface formed the cracks, and also tended to shear the surface into "bricks". Note the brick-like material at the top of the wall, which I take to be low velocity ejecta. The patina, or sheen, of the "caulk" in the cracks would be due to polishing by the millions of years of dust storms subsequent to the impact and the filling of the cracks.
This is my theory which is my own.
I meant to add: There are more shots of the same scene on the Sol 279 page. These are from a different angle, and if you cook up a way to view stereoscopic pairs ( I used MS Paint ) you can see that the "water" surfaces are far from flat, as well as being inclined, of course. Try this left and right pair, which shows the top part of Levin's image viewed from the right side. The horizontal blue portion of Levin's "puddle" on the upper right is seen to have significant relief in this pair. You can actually see this by looking back and forth between the left and right images of the pair, if you don't feel like going to the effort of stereo viewing.
There is a series of images from the Panoramic camera on Sol 290 which closely match Levin's image, including this one. These do have filters on them, but I think Levin has his own ideas about Martian colors.
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The key to the paradox is the famous fact that "viscosity is independent of pressure". The usual heuristic explanation is based on the elementary kinetic theory of gases. Viscosity is due to momentum transfer across streamlines. The crude analogy is of a food fight between passing trains. The transfer of material will speed up the slower train and slow down the faster train. In a thinner gas, a given volume of gas will have less momentum transfer from a nearby volume, but it will receive momentum transfer from a greater distance, due to the greater mean free path of the gas molecules in the thinner gas. Anyway, this means that very fine particles can be taken aloft in a thin atmosphere just as easily as in a thick atmosphere. Note this only applies to fine particles. Gum wrappers would not blow around in a Martian wind, because the atmosphere doesn't have enough mass density, and in this case our intuition about thinner and thicker air is correct.
Re the nature of the "watery" looking material, I think it is dust which has blown into the cracks formed from the original impact. The brighter dust at the bottom is sandy material which has eroded from the surface and come to rest there. I think the horizontal striations are the original layers of the Martian regolith built up by dust storms over millions of years, and the surface we're looking at was scoured and compressed by the ejection of material at impact. Note that the crater is much larger than the impacting body, so conditions that formed this surface are not the most extreme, being at the outer boundary of the impact's effects. I think the compression of the surface formed the cracks, and also tended to shear the surface into "bricks". Note the brick-like material at the top of the wall, which I take to be low velocity ejecta. The patina, or sheen, of the "caulk" in the cracks would be due to polishing by the millions of years of dust storms subsequent to the impact and the filling of the cracks. This is my theory which is my own.
I meant to add: There are more shots of the same scene on the Sol 279 page. These are from a different angle, and if you cook up a way to view stereoscopic pairs ( I used MS Paint ) you can see that the "water" surfaces are far from flat, as well as being inclined, of course. Try this left and right pair, which shows the top part of Levin's image viewed from the right side. The horizontal blue portion of Levin's "puddle" on the upper right is seen to have significant relief in this pair. You can actually see this by looking back and forth between the left and right images of the pair, if you don't feel like going to the effort of stereo viewing.
There is a series of images from the Panoramic camera on Sol 290 which closely match Levin's image, including this one. These do have filters on them, but I think Levin has his own ideas about Martian colors.