Prospects for liquid water: statistics in the Solar System

[h2ouniverse]

With recent hopes raised for Dione and Tethys, the proportion of bodies in Solar System probably hosting liquid water increases further.<br />Below, a table, for discussion. To my count we have now almost one-third of the 33 large solar system bodies probably having liquid water and/or cryovolcanism.<br />More than two-thirds (25) with possible or probable liquid water reservoirs. And 27 with large layers of H2O (liquid, solid, or supercritical).<br />And that does not account for smaller, Enceladus-class objects... <br />Any pessimist reaction to counterbalance my irrelevant optimism?

 

[kyle_baron]

<font color="yellow"><br />Any pessimist reaction to counterbalance my irrelevant optimism? </font><br /><br />Sure, the water will either be ice, steam, or mixed in mud. <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>

 

[deapfreeze]

"Sure, the water will either be ice, steam, or mixed in mud."<br /><br />But its still there. Ice , steam or mud all need some sort of liquid. So lets melt cool or boil what ever we need to. <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p><font size="2" color="#0000ff"><em>William ( deapfreeze ) Hooper</em></font></p><p><font size="1">http://deapfreeze-amateur-astronomy.tk/</font></p><p> </p> </div>

 

[brellis]

<font color="yellow">So lets melt cool or boil what ever we need to.</font><br /><br />Right on - these are potential sites for space stations to help sustain a human presence throughout the solar system <img src="/images/icons/cool.gif" /> <div class="Discussion_UserSignature"> <p><font size="2" color="#ff0000"><em><strong>I'm a recovering optimist - things could be better.</strong></em></font> </p> </div>

 

[h2ouniverse]

The reason why I posted this statistic is the following. Although I expect that many of the places marked "Probable" or "Possible" in my table do indeed have H2O all frozen or in a slush state, I cannot believe that, by "miracle", NONE of them have really liquid reservoirs (water or ammonia+water).<br /><br />The pessimism of those who pretend Europa can only have convecting ice and not water (or water+ammonia)really puzzles me. When you have Io blatantly demonstrating that tidal effects can keep a rocky 3600km-body completely molten, and tiny Enceladus showing cryo-activity, how can one believe that ALL H2O-to-rock interfaces of those 25+ solid bodies are below zero celsius (*) ???<br /> To me it takes a kind of reversed act of faith, quite irrational.<br />I can understand caution in any particular case. But now the tally grows and it is the opposite position that looks less and less reasonable.<br /><br />All cores are relatively hot. I cannot buy that by lack of chance, systematically, all is frozen.<br /><br />Regards<br /><br />(*) an internal or tidal flux of 0.1 W/m² is enough to keep pure water liquid under few kms of ice shelf.

 

[3488]

Hi Joel,<br /><br />Thanks for that. I have downloaded your table (hope you do not mind).<br /><br />I will keep following this & If I find out any more, I will post it on this thread.<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>

 

[JonClarke]

You should add Mercury to the list of possible worlds with water ice.<br /><br />http://www.nrao.edu/pr/2000/vla20/background/mercuryice<br /><br />Amazing!<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[3488]

Hi Jon, Hopefully MESSENGER will settle that once & for all.<br /><br />The article states that the shadowed polar Mercury craters are about minus 235 Celsius, near <br />enough the same as Triton!!!!<br /><br />So Mercury, despite being the closest planet to the sun, is also home to some of the COLDEST places<br />in the solar system. Quite an oxymoron really!!!.<br /><br />So yes, the shadowed Mercurian craters indeed could be home to water ice, delivered by comets.<br /><br />BTW, KBOs 2003 EL61, Varuna & Quaoar have been found to have large<br />quantities of surface crystalline ice.<br /><br />But it is still a brilliant list though.<br /><br />Well done Joel for your research.<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>

 

[h2ouniverse]

Thanks Andrew, Jon<br />Actually my alias says it all... That surge in the tally of potential water-host is precisely (along with exoplanets) the reason why I shifted from telecom satellites to exploration...<br />You are right Andrew, I should add EL61 and Quaoar to the "probable" ones because of cristalline ice.<br />Actually I am currently trying to model EL61 to understand how its equator can be elliptical.<br />I hesitated to include Varuna. its cristalline ice detected is clearly a sign of (at least) cryovolcanism. But the diameter looks smaller than Ceres (TBC), and I had to stop the list somewhere. Unless Varuna is finally acknowledged as a "Dwarf Planet". Given its markedly triaxial ellipsoidal shpe, it may take some time before the criterion of "hydrostatic equilibrium" is evicended. <br />If we include those three, that makes 13 out of 34!<br />But if I add a line, I will exceed 100ko <img src="/images/icons/tongue.gif" /><br /><br />I do not dare to add Mercury. I mentionned "large layers" to appease pessismists. And to be frank, we do not really care about ice [which crazy astronauts are going to take so much radiation, deep into Sun's gravity well?], but water for obvious reasons (exobio!). <br />Jon, Andrew, IYO, is there a possibility that by conduction in the crust from the nearby hot part of the pole, the rock-to-ice interface created pockets of water?<br /><br />Andrew, it is an honor that a professional like you picks up my poor table. And it is my firm intention to keep this list updated as bad and good news arrive in the coming years!<br /><br />Best regards.

 

[h2ouniverse]

Andrew<br /><br />Btw, I guess you would probably put Ariel and other Uranians higher in the probability ranking?

 

[JonClarke]

<i>Jon, Andrew, IYO, is there a possibility that by conduction in the crust from the nearby hot part of the pole, the rock-to-ice interface created pockets of water?</i><br /><br />I would have to say yes! I can't wait until messenger and then BepiColumbo get there.<br /><br />Jon<br /> <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[h2ouniverse]

I realize that I forgot 1995TL8 in the list of Enceladus-class bodies with tidal effect.<br />Actually the uncertainty on the dimensions of TNOs are huge (cf Dysnomia disappointment). But if the first estimates are correct, tl8 is 350 km wide, and being orbited by a 160km moon at just 420 km distance!!!!<br />That means a tidal gravity ratio (*) of 0.7%, comparable to Io!<br />For its moon it's even bigger: 7%!! (absolute record to my knowledge).<br />Whether this tidal attraction translates into heat dissipation is another thing (the binary subsystem might be stable, fully dual-locked). But who knows?<br /><br />(*) gravity gradient / body gravity <br /><br />The two members of the CS29 binary would have, if mass and dimensions are correct, a tidal gravity ratio of about 0.1% (half the one of Europa).<br /><br />Regards<br />Joel

 

[kyle_baron]

<font color="yellow"><br />So lets melt cool or boil what ever we need to. </font><br /><br />I guess that I misunderstood. I thought that he was looking for E.T. <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>

 

[3488]

Hi Joel,<br /><br />Nothing wrong with your list. I thank you very much for going through the trouble of<br />producing it.<br /><br />Regarding Mercury.<br /><br />I have a problem with LIQUID water. AFAIK, the surface of Mercury is a poor conductor of heat.<br /><br />True, like the Moon, there may be mountain summits near the poles, where the Sun never sets.<br /><br />If heat from the areas do conduct into the cryogenically cold permanent shadowed areas,<br />than any water ice would sublime, not go through the liquid phase first.<br /><br />Unless I suppose it is underground & under pressure!!!!<br /><br />MESSENGER in January next year will pass Mercury for the first time (highly anticipated as we get<br />to see 45% of the hemisphere Mariner 10 missed) & then we may<br />get some answers. If not then, definately after orbital insertion in March 2011.<br /><br />Perhaps Jon Clarke might know more than me on this??<br /><br />Another poser for you!!!<br /><br />The Jupiter moon Amalthea.<br /><br />On 5th November 2002, the Galileo spacecraft passed only 160 KM from Amalthea<br />during the encounter A34.<br /><br />The SSI was not used (I was part of a campaign, unsuccessfully, to get both Io & <br />Amalthea imaged), but the gravitation tug od Amalthea was closely monitored.<br /><br />The results were unexpected to say the least.<br /><br />Amalthea turned out to have a density not far above that of water ice.<br /><br />Genrally using the Galileans as a guide, Callisto is less dense than Ganymede, which in turn is<br />less dense than Europa, which likewise is less dense than Io. This was because of<br />Jupiters's immense heat, during formation, preventing volatiles from condensing near by.<br /><br />This trend was expected to continue with the smaller four inner moons <br />(Thebe, Amalthea, Adrastea & Metis).<br /><br />A navigational opportunity came up in November 2002, to enable a close approach of Amalthea.<br /><br />The fact that Amaltheas low density, blows the model of the <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>

 

[centsworth_II]

<font color="yellow">"Regarding Mercury. I have a problem with LIQUID water. <br />AFAIK, the surface of Mercury is a poor conductor of heat."</font><br /><br />I've read that it's thought the core of Mercury is still at least<br />partially molten. Do we know anything about the likelihood of <br />water deep in the crust? Couldn't here be a "Goldilocks zone"<br />below the surface where the heat of the core -- or from radioactive <br />elements in the crust -- keeps water -- if present -- liquid?<br /> <div class="Discussion_UserSignature"> </div>

 

[h2ouniverse]

[[[ I guess that I misunderstood. I thought that he was looking for E.T. ]]]<br /><br />Yes I am. And not hiding it. Microbial life will qualify as E.T. for me. Satisfactory enough for the demonstration this homo sapiens species needs, quite urgently. <br /><br />Btw, places to easily drill holes in are interesting though. But colonization is less urgent than exobio for mankind IMO.

 

[h2ouniverse]

Andrew,<br />Very interesting. OK the ratio for Amalthea is far larger (and probably unbeatable).<br />Which is not good news btw. Because this means that even with such a large tidal ratio, a density of 1 <br />and all the perturbators around, it does not collect enough energy to morph into hydrostatic equilibrium.<br />Or does it ? Can the hydrostatically-balanced surface be hidden under a layer of rubbles?<br /><br />You mentionned heterogeneous density. So would that mean a very porous/rubblish part and a H20 nucleus?<br /><br />Its dimensions are low however. So almost no thermal inertia. <br /><br />Joel

 

[3488]

Possible.<br /><br />What really interests me is how Amalthea stays together.<br /><br />Where did it come from?<br /><br />Did it form so close to Jupiter?<br /><br />Clearly Amalthea has not been able to pull itself into a sphere.<br /><br />A H2O nucleus is certainly possible IMO. I fail to see hew just a pile of ice boulders<br />can keep itself together so close to Jupiter & the purtabations of planet sized<br />& massed moons passing outside??<br /><br />Interesting points you raised there. I hoped that this would happen.<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>

 

[h2ouniverse]

That is the issue with tidal energy.<br />Sometimes it dissipates a lot (Io). Sometimes very little (the Earth): on Earth about 4e17W of tidal energy (700 W/m²), <br />for just 2.6e12W dissipated in the oceans, the rest being used to accelerate the moon on its orbit... A factor of 150000...<br />I hope there are more cases with higher dissipation ratios in the Solar System. I still hope that triple or quadruple subsystems are found in Kuiper Belt and Inner OC.<br /><br />Joel

 

[3488]

I would expect that to be the case.<br /><br />Pluto may yet have more tiny moons yet too.<br /><br />Did you see my post on the update on Eris & Dysnomia?<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>

 

[h2ouniverse]

Andrew,<br />Yes I did.<br />I also computed these kinds of ratios for the Eris-Dysnomia couple, but with the new dimension (and mass!) they collapse significantly. Along with prospects of cryovolcanism...<br />Joel