[X] My Assistant

[Guest_BruceMoomaw_*]

And also this new one (apparent montmorillonite clays on Husband Hill):

http://www.agu.org/cgi-bin/SFgate/SFgate?&...&=%22P12A-04%22

I think "Astronomy" left a brief reference to that in my MER piece. These are the "Independence" rocks -- of which there are at least two whole outcrops (the other being "Assemblee"). Oddly lumpy-looking stuff, which I guess is what you might expect of solidified clay deposits. Squyres thinks they may be other clays than montmorillonite, but there's no doubt that they are clays. Independence's iron content is only 6%, as against the usual 20% for Martian material.

(There's a time when I would have worried about the consequences for MER had the White House found out about all those French names they've been giving to Martian surface features. But now I'm considerably less concerned -- especially since the decline of "Bugsy" DeLay, as one lawyer friend of mine calls him.)

[Guest_paulanderson_*]

Another good clay article posted today on Scientific American:

Martian Claymation
An ancient, watery Mars was not always an acid bath

http://www.sciam.com/article.cfm?chanID=sa...35983414B7F0000

Again about the carbonates though, what about the traces that Spirit saw at the beginning of the mission and the trace levels seen globally from orbit, as mentioned in the same MER update from 2004? I posted the link before, would have to find it again now...

[Guest_paulanderson_*]

A new methane update from Vladimir Krasnopolsky:

Some problems related to the origin of methane on Mars

Icarus - December 15, 2005

http://tinyurl.com/cjf69

If clays contribute to the methane at all, shouldn't there be a correlation between the clay deposits and localized sources of the methane? I don't know if there is yet or not, just an observation.

[Guest_paulanderson_*]

Moreover, I'm currently engaged in an exchange with Brian Hynek, who in turn got into quite a lively fight with the MER team at the AGU meeting as to whether the Meridiani deposits really are due to acidified groundwater, or whether their layering structure and chemical makeup has been misinterpreted and they're really repeated falls of volcanic ash mixed with acidified steam.  Until I hear a response from him to my latest message, I had better not elaborate right now.

Updates regarding this today from Nature, CU and Space.com:

The Waters Ran Shallow
http://www.nature.com/nature/journal/v438/...e051222-10.html

Mars Region Probably Less Watery In Past Than Thought, Says Study
http://www.colorado.edu/news/releases/2005/470.html

New Studies Question Mars Water Assumptions
http://www.space.com/scienceastronomy/051221_mars_dry.html

Regardless though of whether they are correct or not regarding the acidic sulphate deposits in these scenarios, the earlier clays are still another matter...!

Addendum: the Space.com article has now been updated this afternoon, with Squyres' comments (who it says was not contacted prior to the article being published):

"Squyres said a deeper understanding of the situation came when Opportunity examined Endurance Crater, where observations were made of 25 vertical feet of rock outcrops. Those results were published just a month ago, after the two Nature papers had been submitted. Knauth, McCollom and Hynek "hadn't seen that stuff when they wrote their papers," Squyres said. The nature of the layering and grain sizes deeper inside Endurance Crater "is absolutely incompatible with a volcanic or impact origin," Squyres said. It is "completely compatible" with the idea of windblown material, and the upper meter or so "shows evidence for deposition of water. The chemistry varies with depth in a way that requires that subsurface liquid water interacted with the rocks after they were deposited." Squyres emphasized that his team has always thought the water was mostly underground, occasionally creating small surface lakes that evaporated quickly. Squyres also stressed that nobody has done anything other than good science with the data available. "It's always good to have alternative hypotheses," he said. "In the end, the best ideas win. It forces everybody to go back and sharpen their arguments. All of this is a good thing."

This post has been edited by paulanderson: Dec 21 2005, 10:53 PM

[ljk4-1]

Follow The Nitrogen To Extraterrestrial Life

To quote:

Even if NASA were to find water on Mars, its presence only would indicate the possibility of life, said Kenneth Nealson, Wrigley Professor of earth sciences in the USC College of Letters, Arts and Sciences.

"It's hard to imagine life without water, but it's easy to imagine water without life," Nealson said.

The discovery of nitrogen on the Red Planet would be a different story.

"If you found nitrogen in abundance on Mars, you would get extremely excited because it shouldn't be there," Nealson said.

The reason has to do with the difference between nitrogen and carbon, the other indispensable organic element.

Unlike carbon, nitrogen is not a major component of rocks and minerals. This means that any substantial organic nitrogen deposits found in the soil of Mars, or of another planet, likely would have resulted from biological activity.

Full article here:

http://www.spacedaily.com/reports/Follow_T...trial_Life.html