The dark blueish / greenish areas are sediments, not liquid water, which most likely originate from water that was flowing there once in former times.
The evidence for water they found on Mars was NOT in the pictures you refer to in this thread. The water was actually found (as expected) by Mars Express Omega Spectrometer which is a combination of an infrared and optical camera on it's course over the South pole. This Omega instrument discovered traces of the supposed carbon dioxide ice as well as water ice in the areas, where the carbon dioxide ice is currently molten due to martian summer on the south side.
I think the difference in the pictures that Rick showed a couple messages above (Themis vs Mars Express) comes from different treatment (like contrast enhancement etc., color encoding) of the pictures and / or different position of sun casting different shadows, seasonal difference or different coverage with fine dust settling there due to sand storms from time to time and then again blown away.
It has most certainly nothing to do with terraforming and other wild theories originating from wishful thinking.
Lan Fleming 2/1/2004 12:52:11 PM
[[There is no *liquid* water on Mars at all. ]]
Liquid water can exist in some regions of Mars at lower latitudes. Michael Malin, the scientist who built the Mars Global Surveyor even thinks he's found evidence of gulleys formed by flowing water in very recent times geologically -- meaning anywhere from a few million years ago to yesterday.
[[The dark blueish / greenish areas are sediments, not liquid water, which most likely originate from water that was flowing there once in former times. ]]
I'm not claiming that it is liquid water, just that I don't see why that possibility should be ruled out. The ESA scientists don't know what it is. It's probably not water, but it sure looks like it could be. If the colors are accurate, the blue material imust be something pretty unusual. I don't know of anything that looks like that on Earth. The image is from an area of Mars called the Hellas Basin and it's at a low altitude where the pressure is high enough to support the existence of liquid water.
DocMoriarty 2/2/2004 3:28:52 PM
They (the ESA scientists) think these basins or river vales have been formed by flowing water. Just whatever there is now, is no liquid although it looks like it due to the color.
Basically i'd say it has perhaps something to do with copper compounds, they are usually greenish or blueish. For example copper sulfate:
Also copper sulfate is pretty good water soluble. That would explain the sediments. I didn't say there has never been water, just that now there is no water, the color is not to be mistaken with how a lake on earth would look from above.
I don't think that pressure on mars is anywhere high enough so that liquid water could exist for long. Most likely it would dissolve quickly, as in a few hours or days.
Quote from the following website:
"At the atmospheric pressure that exists now on Mars, it is essentially impossible to have liquid water. Either it's ice or it's water vapor."
I think that is probably the best explanation for the blue we see in this area
of Mars. But, how did these vast quantities of copper sulfate get deposited
there? Was it caused by massive eruptions like volcanoes, and this sulfate
flowed out and formed a river, only to pool up at either end? That would mean
huge lakes of it below the surface at one time? What temperature does this
copper sulfate have to be, to turn liquid?
DocMoriarty 2/3/2004 11:52:25 AM
My guess is that there was a spring or water reservoir under the surface and a copper vein and some other minerals that formed a weak acid in which the copper could dissolve to copper sulfate or similar compounds. Part of it got swept outside by tektonic forces, meterite impacts or whatever. When the water was gone the sediments stayed.
There are also signs of instant flooding in some areas on mars and large river vale systems. Now i don't think, that these originate from clouds and rainfall due to the thin atmosphere. But i can imagine, that there is quite some water in some areas usually enclosed in caverns under the surface. Now when a meteroite impacts that might push a huge amount of water in an instant (or two instants *g*) to the surface being responsable for these flood traces and such sediments.
Just a few ideas how these things could have been created.
Lan Fleming 2/3/2004 7:14:14 PM
[["At the atmospheric pressure that exists now on Mars, it is essentially impossible to have liquid water. Either it's ice or it's water vapor."]]
It's a shame that someone at a university, who should know better, would say something like that. The statement is patently false. The phase diagram for water shows that it's liquid in a range of pressures and temperatures that exist at lower elevations of Mars -- not at the tops of Olympus Mons, though; the atmosphere is too thin there. Add some salt to the water and the range of temperatures is even greater. Michael Malin, the scientist in charge of the Mars Global Surveyor camera, thinks he's _photographed_ gulleys in the subpolar regions of Mars that were formed in recent geological times by flowing water. Whether there _is_ liquid water on Mars remains to be seen. There is absolutely no question at all that it's possible.
DocMoriarty 2/3/2004 11:38:25 PM
If my little theory isn't too wrong, the groundwater responsable for the features we see would be pretty loaded with minerals as in being salty or saturated with copper sulfate or similar solutions.
I wonder though, how deep the dust layer of surface material is in average on mars and where rock begins.
Lan Fleming 2/4/2004 4:28:12 PM
Here's an article I found on dark streaks on Mars that are quite common. I contributed to and edited a paper on this subject more than two years ago. Efrain Palermo and Jill England did most of the research, though, and presented it at a Mars Society conference. They concluded the streaks were very possibly seepages of liquid water onto the surface from below ground. This article indicates that the mainstream scientists are finally catching up to us "anomaly hungers." :)
Me being the Independent-believer.. I say it's possibly water, but that a scientist could explain it away in his own mind easily.
A scientist could look at a picture of the atlantic ocean and you told him it was taken on mars he would begin figuring out what it could be BESIDES WATER. Because in their mind it's impossible for their to be water on mars right now.
Scientists are not looking for water or life on mars. They don't believe that to be possible. So, looking for it is just stupid.
Their looking for the possibility that life "COULD have EXCISTED" on mars. Nothing more, nothing less.
Granted, this is why we are so frustrated by NASA.
They ignore/hide/debunk all of the possible signs of CURRENT life.
While orgasming over the signs of NOTHING but rock formations and texture of the landing area.
When astronauts encounter unknown objects in outerspace, they don't investigate to see what it is. They shutup about it, turn off audio and discourage discussion about it.
So, in a nutshell. Were wasting our time on Mars. They have no intentions of finding LIFE.
I think they want benign (SP?) evidence that they can use to say life probably excisted on mars. Without the threat of there being life actually alive on Mars right now.
I guess for me.. I know we are pretending that alien life forms don't excist. I just wonder at what point we stop pretending.