<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'><font color="#ff0000">Kind of old news (other threads have discussed this) and just wanted to point out that it is not our moon, but Saturn's moon.Whatever water is on Titan is frozen extremely solid, even if diluted by materials that would lower it's freezing point. The hydrocarbons are liquid, but AFAIK, we know of no life than can exist without liquid water. That doesn't meanit can't exist, just that we don't know of any (or really any possible way for it).Life is certainly not impossible, but because of the extremely low temperatures would exist in a different time scale than ours on earth. A chemical reaction thet might take milliseconds here on earth, might take years on Titan, because there is so little energy to work with.On the other hand, 4 billion years is a lot of time... <br />Posted by MeteorWayne</font></DIV></p><p><font size="2" color="#003300"><strong>Hi MeteorWayne,</strong></font></p><p><font size="2" color="#003300"><strong>Yes, average surface temperatures on Titan are minus 180 Celsius / 93 Kelvin. Water Ice at those temperatures, is as hard as solid rock, in fact ice is more like glass at those temperatures.</strong></font></p><p><font size="2" color="#003300"><strong>Some cryolavas as speculated on Titan, perhaps erupted by Ganesa Macula, etc, is likely to contain Ammonia, lowering the temperature of freezing to minus 100 Celsius / 173 Kelvin. This could flow for some time, but even this would freeze solid at Titan's surface temperatures. <br /></strong></font><br /><font size="2" color="#003300"><strong>The polar regions & dawn temperatures are slightly lower, averaging minus 183 Celsius / 90 Kelvin (Titan is a lot like Venus in this respect, the average surface temperature on the plains varies only 4 Celsius on both objects, pole to equator & day & night).</strong></font></p><p><strong><font size="2" color="#003300">Regarding biological activity, I remember seeing something about Alcor & cryonics, stating that one second of decay at normal room temperture is something like 250,000 years at minus 196 C / 77 K, the boiling point of liquid nitrogen.</font></strong></p><p><strong><font size="2" color="#003300">Titan is almost as cold, so I would expect biological activity to be almost as slow. Also as the Sun was less powerful in its youth, would Titan have been even colder, more like the moons of Uranus, at some minus 215 C / 58 K? </font></strong></p><p><strong><font size="2" color="#003300">This is more than cold enough for nitrogen to freeze into ice (nitrogen freezes @ -210 C / 63 K). So was Titan at one time a frozen airless body, too cold to hold an atmosphere of significant density, too cold for Methane Lakes, (-185 C / 88 K is enough to freeze over Titan's lakes) like Neptune's Triton, unless cryovolcanism maintained an atmosphere?</font></strong></p><p><strong><font size="2" color="#003300">I suspect Titan now is the warmest it has ever been. Could be wrong though.</font></strong></p><p>
<font size="2" color="#000080"><strong>http://img245.imageshack.us/my.php?image=titanatmdetailvk3.jpg</strong></font></p><p><strong><font size="2" color="#003300">
<img src="http://sitelife.space.com/ver1.0/Content/images/store/7/1/3775a661-d25f-4ea7-9145-694f631b0d15.Medium.jpg" alt="" /><br />Andrew Brown.</font></strong></p> <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>