Posted to sci.astro:

From: Robert Clark (rgregoryclark@yahoo.com)
Subject: Temperatures and pressures are within the range to permit liquid water in Gusev, Mars.
Newsgroups: sci.astro, alt.sci.planetary, sci.physics, sci.geo.geology, sci.geo.mineralogy
Date: 2004-01-15 02:05:30 PST

This article discusses the mudlike material seen at the Spirit landing
site:

Jan. 13, 2004, 2:00PM
Scientists speculate over mudlike material on Mars
By MARK CARREAU
Copyright 2004 Houston Chronicle
http://www.chron.com/cs/CDA/printstory.hts/space/2350159

I was especially interested (or annoyed) by this passage:

"But scientists discounted the notion that the patch of ground they
dubbed "magic carpet" might be mud because the atmosphere on Mars is
too thin and the temperatures too cold for liquid water."

It seems a continual mistake scientists make in discussing the
possibility of liquid water on Mars is that they always look at the
average conditions or the lowest temperature conditions.
But obviously to form mud you only need the surface to be warm SOME of
the time. At other times when the temperature dropped below freezing,
such as at night, the mud would just become frozen. It is important to
note then that in the daytime when the image was taken Spirit has
shown that in Gusev the temperature can reach 5 degrees C during the
day.
It is also important to keep in mind the gamma ray spectrometer on
Mars Odyssey has shown Gusev to be an area of high water content
within centimeters of the surface:

Synthesis of the Testable Hypotheses for Gusev.
p. 14
http://marsoweb.nas.nasa.gov/mer2003/doc/arcadia_03/talks/Cabrol/cabrol.pdf

As far as the pressure, Gusev is at about the same elevation as the
Pathfinder site, and the pressure never dropped below the triple point
for pressure during the entire time of the Pathfinder mission. Since
they are at similar elevations this will also likely be the case at
Gusev.

Bob Clark

cf:

From: Robert Clark (rgregoryclark@yahoo.com)
Subject: Mars temperatures - they're doing it again!
Newsgroups: sci.astro, alt.sci.planetary, alt.astronomy,
sci.geo.geology, sci.astro.amateur
Date: 2002-03-23 06:08:58 PST
http://groups.google.com/groups?th=971ba4533d20c402

--------------------------------------------------------------
For email response, send to same userid as above, but append
Hotmail.com instead of Yahoo.com.
--------------------------------------------------------------

rgregoryclark@yahoo.com (Robert Clark) wrote in message news:<832ea96d.0401070749.dc1273c@posting.google.com>...
> The released color image from Spirit showed clay-like or mud-like
> material near the rover:
>
> Alien Textures 'Weird Stuff'
> Geologists Just Scratching the Surface
> http://www.astrobio.net/news/modules.php?op=modload&name=News&file=article&sid=761
>
> GRS on Mars Odyssey has shown there are near equatorial spots on Mars
> with high hydrogen content, including Gusev:
>
> ****************************************************************
> From: Robert Clark (rgregoryclark@yahoo.com)
> Subject: Re: Los Alamos Release New Maps Of Mars Water
> Newsgroups: sci.astro, alt.sci.planetary, alt.astronomy, alt.life-mars
> Date: 2003-07-26 10:46:30 PST
>
> news_naught <news> wrote in message news:<d8lUa.5$hk.547@dfw-read.news.verio.net>... > why is the rover going there?
>
> Gusev is at about -15 lat. and 185 W long. As you can see in the
> first map on this page, that lies within the area of high hydrogen
> content near the equator:
>
> Photos: Water on Mars
> http://www.lanl.gov/worldview/news/photos/mars.shtml
>
> This is also discussed in this report of Natalie Cabrol et.al. about
> the MER mission:
>
> Synthesis of the Testable Hypotheses for Gusev.
> http://marsoweb.nas.nasa.gov/mer2003/doc/arcadia_03/talks/Cabrol/cabrol.pdf
>
>
> Bob Clark
> **************************************************************
>
> Experiments under Mars-like conditions have also shown that liquid
> water can exist on Mars at least for short periods:
>
> Done deal: Liquid water CAN exist on Mars!
> Thursday, September 04 2003 @ 01:43 AM CDT
> http://www.aoas.org/article.php?story=20030904014348849
>
>
> Bob Clark