Life on Saturn's Moon?

[Lord Tomyris]

http://news.bbc.co.uk/1/hi/sci/tech/8118014.stm

Well, what do we think?

[Hobbes]

There could be primative life on our solar system. I don't believe it's crazy. Even on Earth some bacteria survive in subzero temperatures or even with nearly no oxygen.

[Baron von Sky Hat]

Hmm, very interesting, a little while ago I had actually just been reading this paper summarising some of the results from the Cassini-Huygens mission (http://lanl.arxiv.org/abs/0906.4064 ; Coradini et al). It references this other paper (http://adsabs.harvard.edu/abs/2009GeoRL..3610203F ; Waite et al, 2009) which I haven't read in full yet, but seems to analyse the specific data regarding Enceladus in more detail, rather than a summary.

Enceladus appears to be an extremely active moon, with some very interesting constituent materials. It used to be thought to be too small for much geological activity, but more and more things seem to have contradicted that, and Cassini seems to have near completely refuted it.

It has several geysers on the surface near the moons south pole, which spout water vapour and a whole range of other molecules and even organic compounds (ammonia and benzene are two that are mentioned in the first paper) up out of the atmosphere. This plume appears to freeze some distance from the moon, and deposit material into Saturns `E'-ring, either repopulating lost material, or quite likely the initial source of the ring to begin with (just the E-ring, not the entire system of saturns rings).

Magnetic data seems to suggest that the plumes cause interactions with Saturn's magnetospheric plasma, so enough to be seen near Saturn itself.

So I really wouldn't be all that surprised if further evidence suggests the presence of life. There's a very interesting experiment in which various chemicals thought to be present on ancient earth are in a container, and that material is shocked with electricity, and analysed to see what forms. I've not read specific papers regarding results of specific experiments, however, I have seen numerous summeries regarding large numbers of proteins and similar forming from the `primordial soup'.

In addition to this, bacteria and such can survive in incredible conditions, and have even been shown to survive high velocity impacts, such as collisions of astrophysical objects, supporting the idea of `panspermia' (or `exogenesis', I'm not sure which is the correct term), in which life crops up in all sorts of places and then is seeded across to others via meteorites and similar.
Combining any aspects of either idea, along with what seems to be a moon possessing surface temperatures up to 180 Kelvin (-90 degrees C, admittedly chilly, but not ridiculously so, and that is only at the surface), with likely liquid water and hot spots under the surface, as well as the various organic chemicals detected, it seems very very plausible.
Of course, none of this is actual evidence of life specifically, but it does specifically show conditions for which finding life definitely seems possible.

Then again, Hollywood has taught us that all aliens want to either destroy or subjugate Earth, so from that perspective, the idea of life this close to earth without having attempted to do so already is highly unlikely.....

[Phier]

All you have to say is liquid water and people start talking about life.

Its possible, would be really cool, but its a bit of a leap to assume.

[Alba gu Brath]

What can they do now to try and prove it?

[Phalanx300]

People say water is necesarry, yet thats just how life on this planet developped because of its rich water suply. It'd depend on the planet, for all we know our beginning of life comes from aliens .

[Alba gu Brath]

People say water is necesarry, yet thats just how life on this planet developped because of its rich water suply. It'd depend on the planet, for all we know our beginning of life comes from aliens .

Yea but water is a good starting point in looking for life as we know that it's neccessary for ourselves to survive. So why not start with that we know.

[Baron von Sky Hat]

Yea but water is a good starting point in looking for life as we know that it's neccessary for ourselves to survive. So why not start with that we know.

Precisely. It is plausible that there might be life that exists in a way that we're not familiar with, but from what we know of life, at least, the more likely is that water is an important component.

Certainly of very high importance as well are the organic chemicals found, as we can be fairly certain that, even if there is some other way of life being constructed, we know that the chemicals that made up earths primordial soup can produce the building blocks necessary for life. Therefore the existance of similar organic chemicals anywhere will always seem promising.

What can they do now to try and prove it?

Given the current evidence that suggests that, from what we know of what conditions life can live in, Enceladus is a strong candidate, the only really truly conclusive proof would be to send a lander. Actually find some of the little beasties that might live down there (by beasties, I mean bacteria, rather than crazy things with 400 eyes and 23 legs or somesuch)(though something with 400 eyes and 23 legs would be awesome...).
Heck of a task though, since you'd expect them in the expected liquid water under the ice surface, and turnaround for a mission to be developed, launched and reach the destination tends to be quite a number of years.

The other alternatives are further analysis of existing data. Possibly try and find some indirect evidence such as expected chemicals that are produced by possible living things or somesuch. I'm not certain of exactly what types of chemical data Cassini collected (it had an awful lot of instruments, and I've little idea how any of the ones regarding materials/chemical science operate), so that may be a possibility.

Also, now that the specific location of the plumes of material from the south pole is well known, and it's known to be interesting, there may be some further spectroscopy that can be done (looking for spectral lines emitted by certain elements/molecules in the spectrum of light). Thought I don't know the technical plausibility of that regarding available instruments and telescopes for which that might be reasonable. I'd think that any earth/earth-orbit based telescopes wouldn't be able to do it, given the brightness of saturn so close to it, but as I said, I'm not sure.

All you have to say is liquid water and people start talking about life.

Its possible, would be really cool, but its a bit of a leap to assume.

To be fair, no one has really said that it implies that life is there, merely that it doesn't exclude it in the way many other places in the solar system do.

But you are absolutely right, people do want to find life, so there does very much seem to be a tendancy to lean toward that conclusion for any given evidence. A kind of innate bias, perhaps, but that's always tempered by the fact that all proper analysis is done on actual evidence and facts. So while people may overstate chances of life for a given piece of evidence, it will always be from evidence that is there (at least, from any reliable source).

[Orko]

I think it would take us ages to reach there and build a colony.

[Lord of Lost Socks]

I think it would take us ages to reach there and build a colony.

If we would build a moonbase, we would get a lot farther than what we could by launching rockets from earth. Due to gravity. The moon is the doorway to the rest of the solar system.

[Chaigidel]

we would kinda be obligated to not build a colony if life is possible there

[Phalanx300]

For life on earth water is necesarry, but we have extreme life forms here who don't need water but use something else. There's no proove to think that water is necesarry for life, thats just human selfishness .

[Baron von Sky Hat]

For life on earth water is necesarry, but we have extreme life forms here who don't need water but use something else. There's no proove to think that water is necesarry for life, thats just human selfishness .

On the contrary, to the best of my knowledge, all known life on earth owes at least part of its existence to water. I think some things may be able to survive without water, but would likely not have initially developed without it. It's an extremely important molecule as liquid water seems to provide all kinds of uses for known life, and environments for creation of important chemicals and such.

Obviously there will be an earth-centric view of how life works, because that's all we've got to work from. All of our knowledge of life comes from theories of how it works based on what we can observe. Whilst that does mean that we can't rule out other forms of life, as far as I'm aware we have no comprehensive theories regarding how non-earth-like life would work, so there isn't much to search for to find other types of life if we don't know what would indicate it.

In addition, the methods by which we know proteins can form from certain combinations of organic compounds and conditions means that it could potentially be very prevalent. As such we could expect it to occur on places other than the earth.

So you're right to an extent, we don't know what other forms of life could potentially exist for certain. However, without more idea of what to look for to find those other types, there's not much we can do but look for the stuff that we do know could indicate earth-type life. We have to work off of what we do know and do have theories about.


Also, in relation to what I said earlier about potential follow up missions, I have found some more. At least one other paper mentions the use of the yet-to-be-operational Hershel space telescope for observing millimeter band spectra of the moons surrounding torus of ejected plume material (http://adsabs.harvard.edu/abs/2009Icar..202..280F). Not actually to do with life though, it's in relation to the workings of the outgassing and cloud of material itself. However, it shows that things along those lines are at least plausible, so potentially existing or near-future instruments could be used for further data gathering without dedicated missions to Enceladus.

[Chaigidel]

yeah liquid water is the common factor of even our most extreme life forms

[Orko]

It could be that alien life don't even need water, or air, or food, and maybe they don't even have DNA but something else! Humans are too arrogant and they think that the entire universe is run the same way their blue, little dot does.

[Chaigidel]

we can only operate from what we understand right now orko, if there is life based on things other than DNA, and other than liquid water I am sure we will eventually find them

I know methane and nickle allows microorganisms that dont require oxygen( in fact is poisonous to them Im pretty sure)

and sulfides, ammonia ; there are several chemicals which could act the same way oxygen does in our organics.