Lakes near Titan's South pole too

[JonClarke]

http://www.spaceref.com/news/viewpr.html?pid=23771<br /><br /><i>Newly assembled radar images from the Cassini spacecraft provide the best view of the hydrocarbon lakes and seas on the north pole of Saturn's moon Titan, while a new radar image reveals that Titan's south polar region also has lakes.</i><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>

 

[michaelmozina]

That's a very interesting article, particularly this very tantalizing quote.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>"The lakes we are observing on Titan appear to be in varying states of fullness, suggesting their involvement in a complex hydrologic system akin to Earth's water cycle. This makes Titan unique among the extra-terrestrial bodies in our solar system," said Alex Hayes, a graduate student who studies Cassini radar data at the California Institute of Technology in Pasadena.<p><hr /></p></p></blockquote><br /><br />As they figure out the local ecosystem, it will be very interesting to see how that system works, and how similar it is to the water cycle on earth. Are their clouds involved like here on earth? Thanks for posting that article. <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[JonClarke]

As yet there is no indication of an ecosystem!<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>

 

[jaxtraw]

It's a planet. Let's be honest with ourselves here. Let's stop the lies, the embarrassing silences, let's not leave the unsaid unsaid any longer. We have to be honest with ourselves. We have to face facts like adults. Before the children get hurt.<br /><br /><br /><img src="/images/icons/laugh.gif" /><br /><br />It's a planet isn't it? It's a planet that got captured by Saturn. That's why it's such an oddball in the system, why it doesn't fit with the neat sextet of real Saturnian satellites. Why it's so <i>big</i>. Long ago, it was trying to be a real planet, but a darned big gas giant accreted nearby and poor Titan fell into its clutches, deprived cruelly of its heliocentricity, and perhaps in the process flung Iapetus out into its lonely far far away orbit, perhaps by some kind of momentum exchange I'll be bound.<br /><br />That's why it's such a damned interesting little moon, with its atmosphere and lakes and nine types of ice and its fascinating hydrological cycle.<br /><br />Look at the Jovian system and the Uranian system (and contemplate what the Neptunian system must have been like before disruption by Triton's capture). Throw out Titan, and the Saturn system fits in too.<br /><br />Let's face reality. It'll be hard, but one day we'll be better people for it.

 

[JonClarke]

Who is telling lies?<br /><br />What are emabrassing silences you refer to?<br /><br />What has been left unsaid?<br /><br />Who is being dishonest?<br /><br />Why is the size difference evidence for capture?<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>

 

[michaelmozina]

<blockquote><font class="small">In reply to:</font><hr /><p>As yet there is no indication of an ecosystem! <p><hr /></p></p></blockquote><br /><br />Gah. What an embarrassing choice of words on my part. Sorry about that. <img src="/images/icons/smile.gif" /> <br /><br />http://www.spaceref.com/news/viewpr.html?pid=23787<br /><br />FYI, this article answered my questions about cloud cover, and cloud interactions with the liquid lakes and the "weather system" on Titan. <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[JonClarke]

I've done worse! <img src="/images/icons/wink.gif" /> <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]

in reply to:<br />---------<br />"Look at the Jovian system "<br />---------<br /><br />Hi Jack,<br /><br />I have no prejudice against the capture theory. But if you speak of comparisons, well there are only two gas giants, Jupiter and Saturn.<br />Uranus and Neptune are ice giants. <br />Jupiter has precisely two moons in the same class as Ttian (Ganymede and Callisto). So I don't see why Titan is so odd on the global picture.<br /><br />Regards

 

[jaxtraw]

<blockquote><font class="small">In reply to:</font><hr /><p>I have no prejudice against the capture theory. But if you speak of comparisons, well there are only two gas giants, Jupiter and Saturn. <br />Uranus and Neptune are ice giants.<p><hr /></p></p></blockquote><br /><br />I don't think that distinction is particularly relevant in this case. I think we can generalise to a position that natural satellites which form in situ do so as some part of the planetary formation process (e.g. from accretion disks or perhaps Prentice's neo-Laplacian hypothesis) and we should expect some regularities from natural satellite families. Looking at unusually large single moons, we only have our own Moon, which apparently had an unusual genesis (result of massive protoplanet collision, so didn't form in "the usual way") and Triton, which seems to be a captured ice dwarf, i.e it didn't form in orbit around Neptune either.<br /><br />The final form of the "mother planets" doesn't matter too much I think. I'm just looking at a very generalised picture of bodies of reasonably large size forming with a reasonably regular satellite family in situ.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>upiter has precisely two moons in the same class as Ttian (Ganymede and Callisto). So I don't see why Titan is so odd on the global picture.<p><hr /></p></p></blockquote><br /><br />My previous (perhaps unwise heh) jokey presentation aside, my observation such as it is is that Titan doesn't in general look like the rest of the Saturnian satellite family. It's very much larger, it has large quantities of gaseous volatiles which e.g. Ganymede and Callisto lack. I think there's reason to suspect that it formed elsewhere from the Saturn system. So perhaps Mimas, Enceladus, Tethys, Dione, Rhea and Iapetus are Saturn's orginal satellite family, analogous to the Galileans and the Uranian family, and Titan is an interloper in the system.<br /><br />It's not so much about absolute size. Trying to predict what sizes

 

[3488]

Thanks Jon,<br /><br />Below a nice cmparison between the northern & southern lakes.<br /><br />Titan South Polar Lakes @ 70 Degrees South.<br /><br />As expected, the Titan south polar lakes are much smaller than their northern counterparts<br />as it is late Summer / early Autumn in Titan's southern hemisphere now<br />where as in the northern, it is late Winter / early Spring, so still dark.<br /><br />For Sizes & Masses of the solar system's largest moons, Eris & Pluto in order see below.<br /><br />Ganymede: 1.48 X (10 to the power of 23) KG. Diameter: 5,262 KM. <br /><br />Titan: 1.35 X (10 to the power of 23) KG. Diameter 5,150 KM. <br /><br />Callisto: 1.08 X (10 to the power of 23) KG. Diameter: 4,800 KM.<br /><br />Io. 8.93 X (10 to the power of 22) KG. Diameter: 3,630 KM.<br /><br />Moon. 7.35 X (10 to the power of 22) KG. Diameter: 3,476 KM.<br /><br />Europa. 4.80 X (10 to the power of 22) KG. Diameter: 3,138 KM.<br /><br />Triton. 2.14 X (10 to the power of 22) KG. Diameter: 2,700 KM.<br /><br />Eris. 1.61 X (10 to the power of 22) KG. Diameter: 2,388 KM.<br /><br />Pluto. 1.27 X (10 to the power of 22) KG. Diameter: 2,274 KM.<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>

 

[jaxtraw]

Thanks Andrew, I did look the masses up heh <img src="/images/icons/smile.gif" /><br /><br />Ignoring the abnormals (Luna, Triton), we can see Titan as the solar system's largest moon in terms of its ratio to the primary, in relative terms nearly 3 times the mass of Ganymede.

 

[jaxtraw]

Neglected to say in response to Andrew's post that I think we can ignore moons such as Dysnomia (Eris I) and Charon (Pluto I), which I don't think formed in the same kind of process as the giants' moons. I see the giants' moons as forming by some process concurrently with the primary, in the most general sense by the collapsing nebula dumping its angular momentum into satellites as it collapses, whereas I'm inclined to think that KBO satellites are the result of chance events e.g. collisions and captures.

 

[h2ouniverse]

Take care not to be victim of pattern-recognition excess.<br /><br />One can also see a continuum in the masses of Andrew's list, and not a discontinuity.<br />You have to eliminate Luna and Triton, and Charon too btw to get this "first" rank for Titan in terms of moon mass/primary mass ratio. Makes a lot.<br />Especially when taking into account that the giant primaries are essentially gas or liquid.<br />If you assume that most gas mass in the planetary accretion band has to finally end up on the primary, than you might better consider the ratio between the moon and the CORE mass of the primary.<br />In that case the picutre changes.<br />Jupiter's core is estimated a mere 12 Earth masses.<br />Saturn is between 9 and 22 Earth masses.<br />This means the quantity of "heavy" matter was equivalent or larger in Saturn's accretion band than in Jupiter's.<br />No surprise then that a big satellite could form from the residuals of this band.<br />Again I am not saying this rules out the capture theory. But this balances the view IMHO.<br /><br />Best regards.

 

[alokmohan]

How to explain asteroid system?Does it support the capture theory?

 

[jaxtraw]

Well, I think it's entirely respectable to exclude Luna, Triton, Charon et al. The predominant theory of Luna's formation is from a giant impact- that's not my idea, it's respected science. Trition is widely held to be a captured KBO. Pluto/Charon are more of a double planet and theories regarding their formation as such are wide open.<br /><br />As to pattern recognition, I agree. Noting a pattern doesn't prove anything. It may however lead one to consider whether it's a meaningful pattern or not, which may lead to a fruitful hypothesis. Noting that the continents of Earth seem to be a jigsaw didn't prove continental drift, but was a first tantalising hint towards that theory. There must be some "rules" regarding satellite formation and every little bit helps, I think.

 

[h2ouniverse]

Don't misunderstand me: we are pattern-recognition processers. And IMHO we have to. Refusing to do so quickly leads to narrow-mindedness and intellectual laziness (commonly known as "conservatism").<br />It's just that someimes we go too far, so we have to be cautious.<br />Again, caution shall not be an excuse for not undertaking pattern-recognition.<br />

 

[alokmohan]

30 years back the British astronomer Patric moore discussed all these in fascinating way.Fish in europa,lakes in titan ,many of you may have read Sir Patricks useful sermon.

 

[h2ouniverse]

Jxtrw,<br /><br />Also, I think the collection of ices+rock on one hand and volatiles on the other are probably two separate processes. That is way it would seem more releveant IMHO to consider the cores masses.<br />Then btw, the mall size of Uranian and non-Triton Neptunian moons would be logical, given the very small cores of Uranus and Neptune.<br /><br />Regards.

 

[h2ouniverse]

hi alokmohan,<br /><br />I am not aware of Moore's discussion. Do you have a link?<br /><br />And also: why not fish under Titan's ice crust?<br /><br />Best regards.

 

[alokmohan]

Saturday, 30 December, 2000, 00:03 GMT <br />Top honour for Patrick Moore<br /><br />Saturday, 30 December, 2000, 00:03 GMT <br />Top honour for Patrick Moore<br /><br /><br /><br />Patrick Moore: Career devoted to promoting science<br /><br />Patrick Moore, the man who has done more than any other to raise the profile of astronomy among the British general public, is to get a knighthood from the Queen. <br /><br /><br />If I have made a contribution, I am delighted<br /> <br />Patrick Moore <br />The presenter of the Sky At Night programme on BBC Television was made an OBE in 1968 and a CBE in 1988 . He will now get the new, higher honour "for services to the popularisation of science and to broadcasting". <br /><br />He told BBC News Online: "It came as quite a surprise, but I'm glad it's felt I deserve it. If I have made a contribution, I am delighted. <br /><br />"I never thought that when I first started observing the sky at the age of seven that I'd be given a knighthood. I've been presenting the Sky At Night for nearly 44 years and know that many of the world's leading astronomers were inspired in some small way by my programme." <br /><br />Xylophone skills <br /><br />The BBC show first aired in April 1957 and is now in the record books as the world's longest-running TV series with the same presenter. Patrick Moore has also written more than 60 books on astronomy - all on his 1908 typewriter. <br /><br /><br /><br />Several probes will be heading to Mars in the next few years<br /> <br />He was educated at Cambridge University. His research interests <br /><br /><br />Patrick Moore: Career devoted to promoting science<br /><br />Patrick Moore, the man who has done more than any other to raise the profile of astronomy among the British general public, is to get a knighthood from the Queen. <br /><br /><br />If I have made a contribution, I am delighted<br /> <br />Patrick Moore <br />The presenter of the Sky At Night programme on BBC Television was made an OBE in 1968 and a CBE in 1988 . He will