Will Phoenix Mars Lander find liquid water brines on Mars?

[exoscientist]

<p>Experiments under Mars conditions show water could remain liquid down to -20C to -50C in salt solutions: <br /> <br />Water Could Stay Liquid on Mars. <br />By Bjorn Carey <br />15 November 2005 <br />"Using a planetary environmental chamber - a tank that mimics the atmosphere, temperature, and pressure of other planets - the team exposed various concentrations of briny water to conditions that match Mars' colder, less pressurized environment. Based on these experiments, salty water, it seems, can exist as liquid on Mars. <br />"It was thought that any liquid on the surface would evaporate almost immediately,' Julie Chittenden, a graduate student with the Arkansas Center for Space and Planetary Sciences told SPACE.com. 'These brine solutions enable water to stay liquid at colder temperatures. If you expose these brine solutions to cold temperatures, they can exist for a very long period of time.' <br />"While pure water freezes at zero degrees Celsius, water mixed with sodium chloride and calcium chloride salts - the two salts used in these experiments - remains liquid down to -21 and -50 degrees Celsius respectively." <br />http://www.space.com/scienceastronomy/051115_science_tuesday.html <br /> <br /> The Phoenix lander is to land in the Mars north polar region. It might be thought there would be little chance for liquid water here. <br /> But this report shows modeled maximal temperatures on Mars according to latitude: <br /> <br />Title: On the possibility of liquid water on present-day Mars. <br />Journal: Journal of Geophysical Research, Volume 106, Issue E10, p. <br />23317-23326 (JGR Homepage) <br />Publication Date: 10/2001 <br />http://www.agu.org/pubs/crossref/2001/2000JE001360.shtml <br /> <br /> It appears in Fig. 4 on page 23,231. The maximal temperature at 70 degrees North latitude is given as 250 K, -23 C.</p><p><span class="blogpost"> This is below the freezing point of pure water but the experiments show it is in the range for liquid water brines. This fact is also discussed here:</span> </p><p><span class="blogpost"><p>Making a Splash on Mars.<br /> "On a planet that's colder than Antarctica and where water boils at ten degrees above freezing, how could liquid water ever exist? Scientists say a dash of salt might help."<br /> ...<br /> "One thing we have to be careful of is our everyday experience that water always freezes at zero degrees," noted Hoover. "It doesn't.<br /> Water containing dissolved salts freezes at a significantly lower temperature. Don Juan Pond in Antarctica is a good example. It's a<br /> high salinity pond with liquid water at temperatures as low as -24 &deg;C."<br /> http://science.msfc.nasa.gov/headlines/y2000/ast29jun_1m.htm</p> <p>Some images of Don Juan Pond:</p> <p>http://www.science.siu.edu/microbiology/Antarctica/images/DJP.view.JPeG</p> <p>http://www.science.siu.edu/microbiology/Antarctica/images/M2JC.DJP.JPEG</p> <p>Some reports argue there is no life in Don Juan Pond but this article discusses life found on its periphery:</p> <p>An extraterrestrial habitat on Earth: the algal mat of Don Juan<br /> [correction of Jaun] Pond.<br /> Adv. Space Res. 1983; vol. 3, 8:39-42.<br /> http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11542753</p> <p><br /> Bob Clark </p></span>&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[gunsandrockets]

Interesting info, quite surprising. <br /><br />< The maximal temperature at 70 degrees North latitude is given as 250 C. /><br /><br />250 degrees celsius? That must be a typo!<br /><br />Heh, another thought just occured to me, now we know what really happened to the Mars Polar Lander; it didn't crash, instead it plunged through a surface dust layer and sank into a briny pond! LOL!

 

[3488]

Hi Bob, that is most interesting, thank you.<br /><br />Not sure what temperatures Phoenix is likely to encounter, though I have <br />seen somewhere, -36C, is expected to be reached as a maximum.<br /><br />Phoenix will operate during the Martian equivalent of June, July & August, maybe even<br />September (hopefully).<br /><br />If that -36C figure is reliable, than the chances of extremely saline liquid brines may <br />indeed be possible.<br /><br />This paper reports on an area a little further north than Phoenix, but is <br />indicative of glacial activity & is related to this discussion.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[3488]

Hi gunsandrockets,<br /><br />Yes that is a typo. Even 250 Kelvin (-23 C) would be too warm, let alone 250 Celsius. <img src="/images/icons/crazy.gif" /><br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[silylene old]

As any good synthetic chemist (or ice cream maker!) knows, you can make liquid salt brine baths for very low temperature synthesis (up to about -50C). This was an especially popular method in chemical synthesis for maintaining reactions at -20 to about -50C prior the widespread use of refrigerant recirculation coolers.<br /><br />However, the brines would still evaporate relatively quickly at that reduced pressure of the Martian surface. So the pools would be ephemeral and probably evaporate within days or perhaps weeks (depending on their volume to surface ratio). We would need to be 'lucky' to find one.<br /><br />However, I think it is unlikely that putative briney pools of liquid on top of an ice cap or ice field would be very briney whatsoever. Ice condensed from air is very pure. The only salts that could be within this ice would have had to blow onto the surface from afar. These salty brines that are liquid at -50C are about 30-50 wt% salt (as I recall from long ago when I used to prepare them for synthesis reactions). I seriously doubt that enough salts would have blown from afar onto the icecap to get anywhere close to this level of saltiness. Perhaps 1% salt, but certainly not 30-50% !<br /><br />And putative relatively pure (liq) water from the top of the ice would either freeze or evaporate away long before it spilled onto the salty ground to dissolve enough salts form a longer-lived pool of briney water.<br /><br />Basically, I consider the scenario of finding briney liquid water to be quite unlikely. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[exoscientist]

Yes, gunsandrockets, 250 C was a typo. I edited this to 250 K, -23 C, in the original post.<br /><br /> Bob Clark <div class="Discussion_UserSignature"> </div>

 

[exoscientist]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>As any good synthetic chemist (or ice cream maker!) knows, you can make liquid salt brine baths for very low temperature synthesis (up to about -50C). This was an especially popular method in chemical synthesis for maintaining reactions at -20 to about -50C prior the widespread use of refrigerant recirculation coolers. However, the brines would still evaporate relatively quickly at that reduced pressure of the Martian surface. So the pools would be ephemeral and probably evaporate within days or perhaps weeks (depending on their volume to surface ratio). We would need to be 'lucky' to find one. However, I think it is unlikely that putative briney pools of liquid on top of an ice cap or ice field would be very briney whatsoever. Ice condensed from air is very pure. The only salts that could be within this ice would have had to blow onto the surface from afar. These salty brines that are liquid at -50C are about 30-50 wt% salt (as I recall from long ago when I used to prepare them for synthesis reactions). I seriously doubt that enough salts would have blown from afar onto the icecap to get anywhere close to this level of saltiness. Perhaps 1% salt, but certainly not 30-50% ! And putative relatively pure (liq) water from the top of the ice would either freeze or evaporate away long before it spilled onto the salty ground to dissolve enough salts form a longer-lived pool of briney water. Basically, I consider the scenario of finding briney liquid water to be quite unlikely. <br /> Posted by silylene</DIV></p><p>&nbsp; The concentration of salts would be much less for the ice to melt if the temperature does indeed get to the 250K, -23C, I cited. Keep in mind also that the Don Juan Pond in Antarctica does maintain such extreme levels of salinity that allows it to remain liquid year round even in subfreezing temperatures. Given the high level of salts seen on the Martian surface from all the landers sent so far, it is quite likely such high levels of salinity could also be maintained on Mars.</p><p>&nbsp;However, it would not have to be long lasting pools for possible Martian organisms to survive in. It could happen seasonally and the microbes go into suspended form during freeze over. This is well known for micrbobes on Earth. </p><p>&nbsp;These reports show that fungi could live in subfreezing,&nbsp; briny water:</p>Life Sci Space Res. 1979;17:95-8.<br /> Growth of fungi in NaCl-MgSO4 brines.<br /> Siegel SM, Siegel BZ.<br /> Department of Botany and Pacific Biomedical Research Center, University of Hawaii, Honolulu, Hawaii 96822, USA.<br /> "Long-term studies have shown that common fungi of the Penicillium-Aspergillus group can be grown in a variety of brines or on moist salt crystals, simulating a range of natural terrestrial habitats such as salt flats, or special water-bodies such as the Dead Sea. In general, salt media rich in KCl are favored over other alkali halides; the media become more selective as the salt concentration rises and nutrient requirements become more complex. We here demonstrate that media which resemble the Dead Sea salt mix can support the growth of selected fungal strains, even in the absence of reduced organic nutrients other than glucose. Such media may serve as models for localized microhabitats on Mars."<br /> http://www.ncbi.nlm.nih.gov/pubmed/12296355<br /> <br /> Life Sci Space Res. 1976;14:351-4.<br /> Performance of fungi in low temperature and hypersaline environments.<br /> Siegel SM, Speitel TW.<br /> Department of Botany, University of Hawaii, Honolulu, Hawaii, USA.<br /> "During the past ten years we have observed a broad array of stress capabilities in common fungi including ability to grow in aqueous ammonia and other alkaline solutions, in acids, in the presence of heavy metals, and in various salt media at low temperature. This report is concerned primarily with (a) the performance of Aspergillaceae in a variety of saturated salts, (b) distinctive roles for K+ and Rb+ ions, and (c) the lowest temperatures at which growth in nutrient brines has been observed, namely 267 degrees K in as little as 14 days. We also describe a novel solid medium based upon gelatin, glycerol and water in which fungal cultures growing at 248 degrees K can be directly examined under oil-immersion magnification. The performance capabilities of the fungi show that tolerance or adaptability to harsh and extreme physical-chemical environments cannot be considered a unique feature of prokaryotic life forms. Salt flats, brine pools and other natural hypersaline environments have long been recognized as real ecological niches harboring a range of biota from pseudomonad bacteria and green algae to specialized crustaceans. A notable omission in this ecological record is the fungi, although the group is known to include marine forms."<br /> http://www.ncbi.nlm.nih.gov/pubmed/12678120<p>&nbsp;This is interesting because fungi have a nucleus, unlike simple bacteria, and are therefore considered to be a more advanced life form than bacteria. In fact they are sometimes regarded by biologists as being more closely related to animals than to plant-life.</p><p>&nbsp;In addition, to the citation I gave that gives modeled North pole temperatures, this report gives actual TES measurements during Summer in Fig. 3:</p>Summer season variability of the north residual cap of Mars as observed by the Mars Global Surveyor Thermal Emission Spectrometer (MGS-TES).<br />W. Calvin and T. Titus.<br />Planetary and Space Science<br />Volume 56, Issue 2, February 2008, Pages 212-22<br />http://dx.doi.org/10.1016/j.pss.2007.08.005<br /><div class="articleTitle">&nbsp;</div><div class="articleTitle">&nbsp;It shows 255K being reached as far north as 75N latitude, so would get even higher at the approx. 70N latitude of the Phoenix landing site.</div><div class="articleTitle">&nbsp;The attached image below which is a blow up of Fig.1 in the report:</div><div class="articleTitle">&nbsp;</div><div class="articleTitle">Factors Influencing the Location of Sustained Cold, Bright Spots in the North Residual Cap of Mars<br />J. M. Pocock, W. M. Calvin<br />Seventh International Conference on Mars (2007), Abstract #3210</div><div class="articleTitle">http://www.lpi.usra.edu/meetings/7thmars2007/pdf/3210.pdf</div><div class="articleTitle">&nbsp;</div><div class="articleTitle">also shows 255K being reached at 75N latitude, so even higher at 70 N latitude.&nbsp;</div><div class="articleTitle">&nbsp;&nbsp;</div><div class="articleTitle">&nbsp;</div><div class="articleTitle">&nbsp; Bob Clark</div><div class="articleTitle"><br /> <img src="http://sitelife.space.com/ver1.0/Content/images/store/1/12/11e77651-b5ce-4745-9c00-47e0908eb443.Medium.jpg" alt="" /><br /><br />&nbsp; </div> <div class="Discussion_UserSignature"> </div>

 

[reikel]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>............ However, the brines would still evaporate relatively quickly at that reduced pressure of the Martian surface. So the pools would be ephemeral and probably evaporate within days or perhaps weeks (depending on their volume to surface ratio). We would need to be 'lucky' to find one. However, I think it is unlikely that putative briney pools of liquid on top of an ice cap or ice field would be very briney whatsoever. Basically, I consider the scenario of finding briney liquid water to be quite unlikely. <br />Posted by silylene</DIV></p><p>&nbsp;&nbsp;Hi Silylene. I understand your skepticism regarding any briny ponds <strong>on top of glaciers</strong>..... but what about elsewhere on Mars, in more favorable low elevation/ latitude locales? </p><p>&nbsp; As mentioned earlier in this thread, halides cause freezing point depression -&nbsp;to which one might&nbsp;add<strong>&nbsp;boiling point elevation.</strong> Am I amiss in thinking that this should also greatly lower evaporation rates as well?</p><p>&nbsp;&nbsp;I found a relevant paper to this question at http://www.agu.org/pubs/crossref/2005/2005GL024154.shtml&nbsp;which supports this view. To quote the authors conclusion "<strong>Thus brine formation will increase the stability of water on Mars not only by extending the liquid temperature range, but also by considerably decreasing the evaporation rate.</strong>"; however -&nbsp;thought I would run it by you since I am certainly no chemist, and it would be quite interesting to hear what you think regarding this aspect of the discussion.&nbsp;&nbsp;</p><p>&nbsp;&nbsp;One more paper http://www.lpi.usra.edu/meetings/lpsc2008/pdf/1702.pdf is interesting as well, as it&nbsp;tends to support previous work suggesting&nbsp;a mechanism for a persistent water/ ice slurry as a mechanism for long distance (i.e., subterranean) transport... on Mars <strong>or </strong>icy moons.&nbsp;The conclusion for this abstract seems to partly address a number of related questions for potential Martian brines. </p><p>&nbsp; These papers seem to support the possibility of brine ponds - possibly even somewhat persistent ones. If spectral imaging&nbsp;identifies high halite concentrations in "ideal" locations, can we cross match with gamma ray spectrometer (-h neutron, i.e., water)&nbsp;to id potential future lander sites? </p> <div class="Discussion_UserSignature"> </div>

 

[thejinxkitten]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Experiments under Mars conditions show water could remain liquid down to -20C to -50C in salt solutions:&nbsp;&nbsp; <br /> Posted by exoscientist</DIV></p><p>&nbsp;</p><p>This is a wonderful news. We hope for Phoenix to land safely in the first place and be able to withstand Mars harsh temperature.</p><p>Maybe Nasa should install the Wipers on it's Solar Panels. </p><p>&nbsp;</p> <div class="Discussion_UserSignature"> <p> </p><div style="text-align:center"><img id="f4c1b2ef-0793-4f27-9615-e4e17a5bc441" src="http://sitelife.livescience.com/ver1.0/Content/images/store/4/6/f4c1b2ef-0793-4f27-9615-e4e17a5bc441.Large.gif" alt="blog post photo" /></div><br /> <p> </p><p> -------------------------------------------------------------------</p><p> </p><p><font color="#800080">"there are other worlds than this" Jake Chamber of Dark Tower</font></p> </div>

 

[exoscientist]

<p>&nbsp;Thanks for those links Reikel.</p><p>Just saw this article about the SHARAD subsurface radar experiment on MRO:</p><p>&nbsp;</p><div class="mxb"> <div class="sh"> Huge ice deposits 'seen' on Mars </div> </div> <div class="mvb"> <table border="0" cellspacing="0" cellpadding="0" width="416"> <tbody><tr> <td valign="bottom"> <div class="mvb"> <span class="byl"> By Paul Rincon </span> <br /> <span class="byd"> Science reporter, BBC News, Houston </span> </div>

 

[reikel]

<p>&nbsp;</p><p>&nbsp; Thanks, Exoscientist. I find the debate over the last few years in particular fascinating insofar as the "W" question..... the interesting question here now is where, and for how long water has persisted. I will look up the SHARAD news you speak of when I can - looks quite interesting. </p> <div class="Discussion_UserSignature"> </div>