I have at least one paper suggesting Rhea may be much more interesting on the inside!

I'm getting the impression that the asking 'was it volcanoes or impacts' is a flawed approach. The only consensus being reached seems to be that there are any number of features which could have been formed by either, or both. The 'impacts only' argument seems to rest on the lack of an obvious nearby volcano. Dvandorn makes the good point :

.

The volcanoes only argument seems to over look the role impacts have almost certainly played in shaping every square foot of mars. If a large impact can cause volcano-like effects, and an obvious volcano is not needed for volcanism to occur then it seems that, in the absence of some other clue, both could have had equal responsibility. Given that a major impact may be capable of triggering volcanic activity the divide between the two ideas becomes still more blurred.

Dvandorn:
I believe that flood basalt vulcanism in india has been linked to the chixilub impact, on the other side of the earth.

To sum up, I very humbly suggest it would be worth considering a halfway house theory, taking into account both possibilities, as well as the possibility that the two could be intertwined.
Just for fun, and for volcano pele if he's following this thread Ive attached something on the possibility of impact induced vulcanism on io!

I'm in the UK, manchester to be exact, and I'd be happy to give up some time at the weekend to it. My knowledge of electronics is minimal, but I'd be happy contribute any way I can.

Thanks ustrax that'll make for fascinating lunch break reading!

Beautifull!

To my untutored eye it looks like the channels converge on the midpoint of the largest diagonal crack (highest on the left lowest on the right), which has a depression at its center. Could this be the original vent, and a new one has sprung up at a later date due to the weakened crust in that area? And why does the fan extending from the vent appear dark? whenever I've seen solid co2 its been white.

Sorry Doug and Nigel, thanks for pointing out my typo nprev.

It'll be very interesting, and to be honest I'd like to see it happen. But although for some applications a site on the moon makes sense (like nprev said about the infrared, or farside radio, astronomy), it doesn't sound like they've got a solid application + reason for siteing on the moon. Thats a pity because if they did they might have more luck attracting funds

Longevity perhaps? With no orbit boosting needed it wouldnt be limited to the life time of its fuel supply. I get the feeling they would like this to be semi permanant at least, and if they wanted to service or expand it at a later date that might be easier to do on the moon. Interferometry would probably be easier on the moon than space. The site planned is the south pole, so at the right spot it might be possible to have the radio quiteness of the far side and the communications ability of the nearside, without a dedicated relay orbiter. A south pole location would probably let you find a spot with a fairly constant temperature regime as well. You could point the scope at one spot in the sky for longer from the moon, without having the earth cut off the view. I think that there is also some value in proving that it can be done, so if a compelling reason to site on luna came to light later there is a fairly recent precedent.

Hello everybody, I've developed a bit of a fascination with the moon recently, and so I was delighted to read this about a private group in hawai making progress toward putting an unmanned observatory on the moon. I couldn't find any mention of it in either the lunar exploration or private missions section, so I thought I'd start a thread to see what peoples thoughts are on the idea. Is it a good one, and if so why has it not been done before? What exactly will it be used for?

FWIW I agree, but I'm going to be heartbroken whichever way the cookie crumbles.

Ive not got acess to the full article but this sounds like material in europa orbiters favour....

Happy new year unmanned spaceflight fans, it's looking to be an interesting one! Cheers one and all!

Can't say how important this is but it's connected to searching for martian carbonates so I'll post it here. I trust doug to remove it if it owes more to good PR than science!

Happy christmas all, hope the new year brings more suprises and conundrums!

I'd count myself as one more. Although I don't think we should stop at mars

I dont know about squid but there are many studies ( these two are a random selection) showing that microorganisms can survive entombed in ice, which would at least tell us there was something down there. Europas ice sheet might prove to be an interesting habitat in its own right, and much more accesible than the ocean itself. Investigating the ice at increasing depths first would give us a chance to test out various approaches, giving us a better chance when we feel ready to, er, take the plunge into the ocean itself. Although if we could come up with an approach that would let us do it tomorrow I'd say go for it, even if it were a shot in the dark!

Thank you very much one and all, I can look foward to a very interesting conversation ensuing on monday when we see each other again!

I have a question I've not been able to resolve and here seems the best place to ask it: The atmospheric pressure of mars is around the triple point pressure of water, hence on a day of high atmospheric pressure and a temperature above freezing (or with the right impurities) a puddle of liquid water could remain on the surface as liquid , but with a very reduced boiling point compared to earth? That is what a great many articles I have recently read seem to assert or imply. However a chemist friend of mine has just argued to me that the triple point pressure on the phase diagram is the partial pressure of water vapour, and since on mars a H2O partial pressure above 6.1 millibars is almost impossible to build, liquid water is indeed impossible on mars! He is quite convinced, but I find it difficult to accept that so many journals and articles have been mistaken over such a fundamental fact. In fact I have read papers on experiments showing that brines at least can remain stable and liquid at mars atmospheric pressure  water2.pdf ( 134.75K ) Number of downloads: 1308
, but I am at a loss to explain how this is possible to my friend!

EDIT:So you all know I'm not just being lazy, I've googled and wikipediad and gone to the university library, and although I've found both versions I've not found anything that clarifies the difference, or addresses the question directly.

I love a conspiricy theory, as long its original and out there enough to be amusing! Hmmmm, I cant decided if doug was brainwashed by the CIA, MI5, or a consortium of spaceflight enthusiasts tired of manics waving pictures of that s***ing hill in cydonia mensae!
I followed a link on the planetary society website.

Thanks!

Does anyone know where to find CRISM images of potential phoenix landing sites please, I've had no luck at all at the CRISM website!

Edit: I have seen some near thumbnail sized versions, and I was wondering if the images simply weren't on public release yet?

The impression I got from the article was that the 16% figure was a first and worth making a bit of a fuss about. If some of the water is present as fluid inclusions that would be exciting, but I dont know if theres any way that could have been determined.

I only just caught up with this thread, congratulations nprev!

The only contribution I've got to make to this is enthusiasm-so here it is: GO DOUG, GO BALLOON!