I think it was not neccesary to quote the entire response and paste a single line at the end - but so be it. Let's look at the compounds in question and whether they are present on Mars. First, we need to understand the whole controversy.
I will start by presenting the original paper for Viking to explain what was being searched for.
http://mars.spherix.com/spie2/Reprint75.htm
They measured the relative humidity and landed. This area where maximum relative humidity was know to be present was near the north polar cap. Now, Malin space Science Systems's version of the Viking hardware:
http://www.msss.com/http/ps/life/life.html
They proposed that reactive hydrogen peroxides would be present and would sterilize the soil.
Note that these reactive compounds would be destroying the aluminum parts of the landers, but we see no sign of this. Note also that these proposed reactive peroxide compounds would also destroy any magnetic iron oxides, but there are magnetic iron oxides present on the trap magnets. Therefore, they have not been destroyed by these proposed peroxides.
The conclusion is simple - since the rovers are not corroded, and the iron oxides are indeed magnetic, then there cannot be any significant amount of peroxides present in the soil. No peroxides means no inorganic explanation for the results, and that means that biology is not ruled out.
The GCMS, as it happens, was never capable of identifying organic compounds as such. It can detect compounds that contain carbon, but it cannot distinguish between organic and inorganic. That is a fact. However, they chose to use its results (which can't tell the difference) over three other experiments that gave positive results for organic activity or compounds. This is selective seeing.
One more very important consideration should be noted. In all cases, there is no proof provided by the "dead, dry Mars" people. They always resort to "the consensus opinion" to explain the results, NEVER the measured and factual data.
In other words, for all the money and effort invested, they always come to "the consensus opinion". This is not good enough. It is hand waving.
Let's look at the harware and its goals.
http://csep10.phys.utk.edu/astr161/lect ... iking.html
These are the Viking instruments meant to look for evidence of life on Mars:
Gas Metabolism: look for changes in the atmosphere induced by metabolism in the Martian soil.
Labeled Release: Look for release of radioactive carbon dioxide by metabolism from organic material labeled by radioactive carbon.
Pyrolytic Release: Search for radioactive compounds in soil by heating soil exposed to radioactive carbon dioxide.
Mass Spectrometer: Search directly in Martian soil for organic compounds known to be essential to Earth life. (This instrument is otherwise known as the GCMS)
The first three gave positive results, the fourth did not - but it was the flawed instrument, unable to detect organic compounds (GCMS). In other words, they chose their own personal bias over the readings of the scientific instrumentation.
http://www.spacedaily.com/news/mars-life-00g.html
Here are the words that outline the whole controversy:
The tests showed that the pre-flight Viking GCMS test model could not detect organic molecules in Antarctic soil sample that contained life. Yet this would be the instrument used to render the final verdict against any positive evidence of life on Mars that might have been found by the Viking biology instruments.
In other words, NASA chose to use the GCMS results even though actual tests showed it to be flawed and incapable of detecting organics in real world tests. Let's see what else was said:
Strangely enough, one of the other Viking biology instruments known as the Pyrolytic Release experiment found traces of organic matter forming inside its test chamber. This occurred in seven out of nine PR tests.
Another instrument, known to word properly, did in fact find organics in nearly all its Martian soil samples tested. It did work on Earth, where the GCMS did not. It is silly to assume that the roles would be reversed, simply because they were on Mars later.
Titled "The Missing Organic Molecules On Mars" (published in the PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES, Vol. 97, p 2425, March 18, 2000), Benner et al., concluded that the Viking GCMS was insensitive to certain organic molecules including those left behind by any microbial life that might have been on Mars.
Again, confirming that this GCMS was a flawed instrument and blind to the very compounds that they needed to detect.
Now fast forward to MER.
Let us look at the presence of carbonates are present on Mars.
http://science.nasa.gov/headlines/y2001/ast04feb_1.htm
"We know there are carbonates (on Mars), because we see them as weathering products in a variety of Martian meteorites," said Everett Gibson, an astrobiologist at NASA's Johnson Space Center in Houston, Texas.
Testing Martian meteorites shows that they contain carbonate minerals. These are direct samples of Mars itself, and they contain carbonates.
Tiny patches of carbonate like those found in the "Mars rock" would not be detected by the thermal emission spectrometer currently in orbit around Mars, Gibson continued. Even THEMIS's 100-meter resolution isn't likely to reveal such diminutive deposits.
In other words, the instruments are blind to small deposits like they have already found from the meteorites. But not all instruments are blind to carbonates, because the Mini-TES can see them.
Here is what NASA considers proof of carbonate minerals on Mars, based on spectra.
http://www.psrd.hawaii.edu/Oct03/carbonatesMars.html
Note that they say that 2% to 5% of the dust blowing over the planet's surface is carbonate. So we have spectral data saying there are carbonates, and they have actual meteorite samples that prove that there are carbonates. That is solid enough for me, as the two data from two remotely different sources confirm the presence of the material. But it gets even better:
http://physicsweb.org/articles/news/7/8/12/1
Although the researchers do not believe the wet scenarios for ancient Mars, they still did in fact find carbonates. Keep in mind that dust blown over the surface can cover any deposits, so they would not be detectable for most instrumentation.
Each of the two rovers contains a Mini-TES. Dr. Phil Christensen is the man responsible for this instrument. He has confirmed the presence of carbonates on Mars using this instrument. Although he has not located a specific outcropping of carbonate minerals yet, he has located the signature in the soil all over.
So yes, there are carbonates on Mars, and the pyrolytic release experiments showed that 7 out of 9 soil samples tested showed positive for organic matter.
Further analysis of the Labeled Release Experiment showed a circadian rhythm in the release of the gas in the experiment chamber - exactly of the period that you would expect from living organisms that have their biological clocks set to Mars days.
Now, let's look at the details of the sodium chloride findings.
http://www.uwo.ca/earth/people/king/res ... aters1.pdf
The charts on page 51 are particularly interesting. They show the relative concentrations of various salts in percentages and where the Martian soils from Pathfinder, Viking, and MER fall. All show sodium and chlorides in their salts. Looks like table salt to me.
http://www.astrobio.net/news/article859.html
Look at the APXS data and you will see the chlorine signature on the curve. Chloride and bromide salts are present, and this is the signature of the chlorides. The interesting thing is that as the water receded and the solutions dried out, the crystallization separated the salts into different families, based on their solubility.
In other words, the sodium chloride settled out of solution at a different time from the sulfate salts species. So the result is that it is in fact present, but separated by where the water level was and what the brine concentration was as the oceans dried up. The lack of huge chunks of halite is not an issue. The sodium chloride is there, just crystallized in deposits they have not driven over. This is expected, since it would have dropped out of the brine solution at an earlier time than the sulfates, apparently.
So using the Mini-TES on the rovers, carbonates have been identified. And, using the APXS (also on the rovers), they found sodium chloride as well as other sodium and chlorine compounds. The most interesting thing for me, however, is that even though this was a "find the water" mission, they have absolutely no device on either rover that can find water. Not even a simple pair of platinum wires that can touch the ground and see whether it is damp! This is just plain silly.
And what about that peroxide hypothesis that has been thrown about for ages? Let's see, thirty years now, by my reckoning, since Viking. If this is a main theory against the presence of life, why is there no instrument on either rover (or pathfinder) capable of identifying, unambiguously, the presence of peroxides? This is just plain criminal. With a stroke they could have proven or disproven their claims. They chose not to include these absolutely essential devices on the rovers.
Now, how about liquid water? NASA admits that Mars was wet in the past, but they deny it for the present. Yet they do it using weasel words. Here is how they pull it off:
http://www.astrobio.net/news/modules.ph ... le&sid=842
In the article they say:
It may find evidence of liquid water on Mars. Well, not exactly liquid water. Liquid brine, actually.
In other words, they think that brine is not liquid water. Or at least that is what they are saying. Yet brine is liquid water with salt in it. So they are saying that if you find brine on Mars, you have not found liquid water. This is absolutely incorrect.
I would hardly say that Salt Lake in Utah was not liquid water, just because it is brine, nor would I deny that the Dead Sea was liquid water. But this is exactly what they are doing in their inscrutable way.
This is exactly why the results are so confusing to most people and to the press - they never say outright in plain English what they mean. They always waffle and qualify until nobody is really sure what it is that they are saying. Well, here is the plain English.
NASA found that Mars had large bodies of salty water in the past. That sounds like seas to me. They found that much of the surface of the planet never falls below 6.1 millibars of pressure, the exalted triple point of water - and that as a consequence, there is a range of temperatures where liquid water can indeed exist on Mars. That is exactly what Gil Levin and Derek Sears have beein saying, backed up by experiments in vacuum chambers. They found carbonates and table salt, and they have decided that brine is not liquid water.
No wonder that people are confused.