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An early image from a JPL news release e-mail showed an image of the surface of Mars including the eclipse shadow spot of Phobos. I thought it interesting, and installed it as the background for my Windows PC. It was not a high resolution image. It showed the Phobos shadow and craters around it. What became really interesting to me as I looked at the image was the fact that dark spots apparently in the bottoms of craters in the field of view only showed up in the image taken through a red filter, and barely, if at all, in the same image taken through a blue filter. The spots appeared a bluish green in a third image made up from the red and blue image information to show a version in color.
My interest was high because in looking for applications for a device I patented, which can be used as an imaging spectrometer, I researched the idea of utilizing the spectral resolution inherent in the device to discriminate between green pigment camoflage materials and chlorophyl, thinking it might be of interest to the defense community. (I was working for McDonnell Douglas at the time.) Chlorophyl absorbs red light in order to achieve photosynthesis, it uses a little of the blue, but not much.
The fact that the dark spots showed up in the bottoms of craters where moisture would accumulate, if it were there, made it seem more possible. I later learned of the paper by the Levines: http://www.biospherics.com/Mars/spie2/spie98.htm which lent the possibility more credibility.
The image inquestion has been the only one I've found with the red, blue and color images side by side in that fashion. Wouldn't it be interesting if a refined instrument could detect chlorophyl and the implied presence of water from orbit in this way?
Rex G. Carnes
Rex G. Carnes
If the Meek Inherit the Earth, Where Do All the Bold Go?
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Do you have a link to that image of Phobos casting a shadow on Mars?
To achieve the impossible you must attempt the absurd
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This is the link to the image of Mars/Phobos shadow/Spots in craters I mentioned.
http://mars.jpl.nasa.gov/mgs/msss/camer … 99_phobos/
Rex G. Carnes
Rex G. Carnes
If the Meek Inherit the Earth, Where Do All the Bold Go?
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Hi Rex! One or two points about the images you mention.
It is intriguing that the red filter gives such clear dark spots while the blue filter all but eliminates them. And, given that chlorophyll absorbs red light selectively, I see where you're coming from on this!
But what about the NASA explanation? Do we know of any kinds of "dark sand" which would give the same effect? Obviously, if there is a perfectly rational mineralogical explanation, and being obliged to employ Occam's Razor in such cases, then we must assume we're looking at dark sand!
Another thing I noticed is that the spots all seem to be "smeared" to the lower left of their craters. (If up is north, this smearing is toward the south-south west.) In fact, the dark colouring seems to climb up the crater wall, and even extend well beyond it in one case. If, as you contend, the colouring is due to life forms dependent on transient surface water at the lowest point on the crater floor, why would such a life form grow up the dry crater wall and out onto the freezing, dry, wind-scoured plains? And why is that "growth" taking place in the same direction in the case of each crater?
I don't want to argue against life on the surface of Mars. In fact, as I've said more than once in New Mars, I'm quite convinced that there is life on Mars' surface; perhaps all over the place! But I know what NASA is going to say here: The dark markings are just sand, and the reason for the smearing, always in the same direction, is simply because of the prevailing winds.
And, if we can't show that it's impossible for sand to selectively reflect different wavelengths of light so effectively, then we probably have no choice but to accept their explanation; whether we like it or not.
Come back to me, Rex, and convince me NASA is wrong. Nobody would be happier than me if you did!!
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Thanks for the post, Shaun. First, let me say that the "evidence" I pointed out does not have to be absolute and definitive to be evidence. Two different broad band color filters placed in front of two different CCD arrays do not constitute an spectrometer in any but a most basic sense. If it happens to seem to work at all it simply implies that simple improvements in technique may provide a powerful moisture/life survey capability.
As for the wind blown aspects, life, in the form of spores, can be propagated by the wind. Certainly other more advanced forms also use this as a propagation strategy. Since the possible density of a miniscule unit of life containing enough DNA, or RNA to propagate will tend to be less than the same size unit of a mineral substance, we don't have much to keep a good life form down, considering that there is good pictorial evidence for blown dust and sand on Mars from Pathfinder and Viking.
To make the remote sensing of chlorophyll more definitive, compared to greenish minerals or agregates of minerals, spectral resolution should be fine enough to pick out the fine spectral structure of chlorophyll. See http://ghuth.com/NEWChloroplast.htm for some data and references. If there is a mineral, or combination of minerals, which can mimic the chlorophyll spectral response, I hope someone can show me as I'm open to it and would like to know. I haven't done a thorough search for such interferences.
Rex G. Carnes
Rex G. Carnes
If the Meek Inherit the Earth, Where Do All the Bold Go?
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