Another world thats still mysterious!

I tend to agree, but the case for cryovolcanoes on titan isn't proven yet! Bear in mind though that even if Titan isn't volcanically active, it's almost certainly seen enough heating and aqueous cryolavas from impacts over it's history to load the crust with astrobiologically interesting materials. The estimates I remember for the life of a water-ammonia melt pool for biggish craters on titan were hundreds to hundreds of thousands of years. I would think something the size of Menrva would fall into the higher end of the spectrum.

On a bit of a tangent, are there any examples on any world we've explored of volcanism driven by impact melts?

I remember reading it was magnesium carbonate, although I can't remember where.

It's a little known fact that there were three brothers, Ienstein, Einstien, and Einstein. Albert was actually their family name (the family had Asian roots). The first two shared the limelight, taking alternate holidays, to preserve some privacy for the family. Albert Ienstein is a character best left unremarked upon....

Or maybe I just made a spelling mistake....

Isn't Menrva large enough that any volcanism inside the crater was most likely due to the impact melt beneath the crater bubbling up? How long would the melt from an impact that size stay liquid? If it's a long time compared to local weathering and deposition might the crater be erased and leave an underground lens of liquid which could then erupt to the surface as volcanism? Obviously this didn't happen to Menrva, but titan must be hiding a lot of impact scars, could ancient melt sheets lead us down the garden path with regards to volcanism?

I'm just stream-of-thought-ing here.

Thanks! I've had a quick look, but I've not found anything relating to the growth of thin water films under matian pressures and temperatures, although this and this might have some interest for anyone with access to springer link.
I think it's an experiment someone will be doing at some point in the near future though!

Well we have a layer of ice, lying below a fairly complex regolith mixture containing water absorbing salts, as well as grains for water molecules to adhere to, and probably a small amount of ice in some form, topped by water/CO2 frosts and snow coming from an atmosphere that supports water ice clouds. So there's a lot of sinks and sources of water, which means complex behavoir for water in the soils is pretty inevitable.

On the subject of the films, the impression I get on re-reading the release and the articles is that the team are probably being a little cagey because there's still a lot of analysis ahead.
My hunch is that the films are probably averaging less than one molecule thick throughout most of the soil, and hence form as a series of patchy 'islands' around favourable spots for water molecules to deposit. That would make them much harder to 'see' as a continous electrical path through the soil wouldn't be there. So when the team digs into the data they may find evidence for these islands of water activity, but hesitate to describe them as films, because....er.... well they aren't they're little islands of H2O clustered together!

I'm going to be hopelessly pedantic here Doug: the report describes that

However the preliminary results, described in this article were that:

If the films were around the one molecule thick mark, or the electrical characteristics of the soil were different than expected, or any one of a zillion things, I totally get that the readings might have needed carefully examining before the evidence was apparent. I'm just wondering how exactly they got from 'the soil is puzzlingly free of water', to 'the soil has some thin films of water molecules'.

Sorry for the pedantry, I'm just being greedy for details really.....

Is this a complete turnaround from previous reports, or did I miss something?

Very cool!

!

Thats beautifull, but quite scary...

If this is in the wrong place someone please move it: A new chapter in the debate over a Martian ocean.

This question may have been previously discussed (I may even have asked it myself) but finding a single answer in the mass of titan info is more than I can take on at the moment, so I'll ask and hope someone can point me to it:

How long do amino acids last for in ice under conditions such as those found on the surface and near subsurface of titan? Or to put it another way, how recent does an impact or cryovolcanic eruption need to be to have produced a detectable amino acid signature?

EDIT: Since we have identified amino acids in meteorites that have likely not seen any activity since the solar system formed I'd hazard a guess that its a long time, but I'm looking for a number. This paper studies the effects of uv exposure at around 100K, but I imagine that the surface of titan is pretty well shielded from UV, so these numbers wouldn't apply.

That said, cosmic radiation can produce uv photons as it passes through ice, so there will be a rate of decay and while the radiation environment at saturn is not as intense as that from jupiter, it might be fairly high. If thats the case we may have to look meters deep on titan for the most biologically interesting chemicals, or hope we get lucky and identifiy a fresh cryovolcanic outflow or impact crater.

My bad Doug, it was very rushed. Thanks for fixing it for me!

Opal on mars, there may be some expensive necklaces come from this discovery...

...Which has in turn got me wondering; has any experimental work been done on what happens to tholins (or other likely photochemistry products) when introduced to ammonia? All the papers I can find are about ammonia water mixtures.

I'm not sure how long that 'eventually' is though. Storm clouds on earth can last for days, how long does it take for tholins in contact with water to start forming interesting things? The sheer scale of things on jupiter or saturn might work to draw things out a bit longer, and the chemical complexity of jupiter (ammonia clouds as well as water souunds interesting) probably allows a much greater array of reactions to take place.

The short span of time would mean that any reactions that would take place would have to do so fairly fast, and there is abundant energy to drive them, which would make a nice study in contrast to the grand slow pace of reactions on titan- different ends of the same scale if you like.

From what i've read there are water clouds, likely consisting of liquid droplets rather than ice crystals, and hydrocarbons such as benzene have also been detected. If we are searching for molecules of astrobiological interest why doesn't the combination of liquid water drops, organic chemistry, and abundant energy make jupiter more interesting?

Everything eventually gets pulled back down, cooked, and recycled but wouldn't it be of interest to see what chemistry takes place while these things are in the upper reaches?

Edit: I may well be treading on thin (forum rule) ice here, so if this post is innapropriate, or looks to start an inapropriate discussion, I hope an admin will remove it.

Lightening on Titan? Does anyone know enough to speak on this, i've no idea what to make of it!

Thanks guys! The sheer scale and complexity of jupiters atmosphere, and by extension tthe other gas planets, is fascinating, and I didn't realise there were still so many mysteries to be solved there. We don't even know why the GRS is red?! I think theres still a lot to learn from jupiter!

Learning about Jupiter, and about the Great red spot has made me feel humbled, and a little afraid! So, I'm going to have a stab at some err...poetry, I'm sure one of the admins will remove or move it if it's not appropriate here:

No mere storm, like the delicates swirls of white on other worlds
It is not its color, that of blood, that marks it out
Or its size, as vast as worlds
But its survival, all down the dark, turbulent, ages and chaos of its home
And the murder of its weaker kin, dismembering and feeding
Like a thing with a dark, coiled, will of its own

Its reign continues
All usurpers crushed
Its stares out at the stars
Jupiters great beast

I've been reading up a bit on this, and I keep running across the phrase 'experts believe this (presumably consuming/tearing up other storms) may be how the great red spot has sustained itself for all these centuries' or similar.
However I can't find out who these experts are or when they suggested it! It seems very reasonable, since jupiter storms do merge with each other to become bigger and stronger, and it clearly owned red jr without any problems, but who actually suggested that this mechanism is how the GRS has lasted so long?

I also came across the notion that the GRS is a strange attractor, and that jupiters atmosphere must produce at least one storm like it at any given time- is there anything to that or is kookery? I intend to keep searching myself but any guidance (I've never been much interested in jupiter before) would be much appreciated!

Actually I've looked for but not found much published on haze particles reaching the surface, which is a bit of a mystery. Has anything been mentioned at the DPS conference, I've not had time to follow it properly?

Edit: I realize that there are dunes covering some 20% of titans surface for which there is evidence of organic composition, but their relationship to the haze is unclear, and I've not heard anything on when these deposits were put down, or over how long. From what I've read it's assumed (reasonably, but still an assumption) that the organics in the atmosphere are precursors of the organic 'sand'.

I'm wondering if there are any papers or articles out there discussing haze particles being deposited on the surface today? It just seems like a big missing link if we can't point to a patch of deposits on titan and say: that came out of the haze.

Thanks John S and every one working on Cassini, I will now sit quietly and enjoy my goodies!

The ocean is still a speculative idea. I would have thought that if heimdall or any other impact had drilled into a preserved limestone layer (as opposed to a one-off deposit) it would be a detectable band in the crater?

As the OP notes carbonates on mars seem to be found as tiny inclusions and tiny regolith grains. This sounds to me more like water condensing in pore spaces in the rock during damp periods, giving rise to carbonate grains which are then eroded out by wind action and mixed in with the soil. I don't even know if that can happen but I've never heard that carbonates need large amounts of water to form only that they need water.

For these to make up six percent of the soil it must have happened many times, (perhaps too many times to be plausable?) but if we are going to have a major sea or lake bed as our source we need a 'smoking gun' with some signs of large scale carbonate deposits.

Now for some unfounded speculation:
Could the carbonate grains even be more contempory? If water vapour can build up enough in pore spaces today to make small amounts of liquid (perhaps if the rock had the right salts included in its structure as impurities?) could carbonate grains be slowly forming today? If it occured in soil pores might that explain the TECP results; thin films of water don't form because the water is being drawn into the few soil spaces with conditions right for liquid H2O? Can osmotic pressure (dimly remebered from school) work that way?

Anyway I'd like to see a crater with a ring of carbonate or a half destroyed carbonate deposite before we decide the grains started out as one big piece. My babbling for today.....