Cassini Finds Evidence of Water 167
CheshireCatCO writes "Scientists working on the Cassini Mission think that they have found compelling evidence for the existence of liquid water at the south pole of the moon Enceladus. In addition to the obvious puzzles relating to how temperatures can be held high enough for liquid water, the presence of water, as well as the detection of organic molecules, opens up the possibility for life at Enceladus's south polar region. The findings are to appear in the 10 March issue of the journal, Science"
Yeah, sure... (Score:5, Insightful)
2) Make allusion to possibility of life emerging there
3) ???
4) Grant Funding!
I'm as much a fan of discovery as the next scientifically minded person, but this has become a little tired in recent years. Every time a possible discovery of liquid water creeps up, the potential for life always follows in the very next paragraph if not the next sentence. One would wonder what would happen if we found a vast reservoir of liquid water but no life in it. I imagine some segment of astrobiology would be so incredulous as to insist on probing it until an earth born microbe manages to survive the trip and contaminate the discovery.
When I was first reading this I thought "Wow, wouldn't it be interesting to figure out how liquid water could have existed there." Then came the inevitable "hey, maybe there's life there!" I just gave up. The conditions for liquid water are remarkable enough, do we need to include the outrageously small probability of life developing before we've looked at the more answerable questions like "where's the heat coming from?"
Re:That is some cold water (Score:3, Insightful)
But why not just do something similar to the Mars rovers? Have a self-contained laboratory that can do all the necessary analysis there. It'd probably be a lot cheaper than trying to retrieve a sample and return it here, and you wouldn't have to worry about contamination, etc.
Re:Predictable rabble (Score:4, Insightful)
The news: The most simple and common combination of two extremely common elements might have been noticed on a large rock, very far away.
Like most astronomy news, it's incredibly boring unless you let your imagination run wild and start dreaming about colonies, alien life, or other flights of fancy... so it's no surprise that most of the
Re:Yeah, sure... (Score:5, Insightful)
I mentioned the possiblity of life only because of the detection of organic molecules. Frankly, I think that the odds of life are quite slim, but this discovery *does* add Enceladus to a rather short list of good places to look. Even if there is no life, we can learn a lot about the abiotic formation of organics and probably put some better constraints on the conditions under which life might develop. So I'm not saying that there is life or that we should expect to find any, merely that this makes Enceladus an interesting place for astrobiologists.
Re:Supercooled water (Score:2, Insightful)
JRjr
Re:Yeah, sure... (Score:3, Insightful)
Well that's just the POINT, isn't it?
I mean, right now we have liquid water on one planet, where life developed. Statistical correlation of 1.0 (great!) over a sample size of 1 (not so great).
Neither you, nor I, nor Carl Sagan, nor all the scientists at NASA knows/knew whether the 'probability of life' is large, small, or somewhere in between. What we're talking about though is DOUBLING our sample size which is a pretty big deal, although still doesn't get us very far (statistically speaking).
Re:That is some cold water (Score:4, Insightful)
Well, if all you had to care about was contaminating the sample you took, what's the big worry? The worry is that microorganisms are incredibly resistant and could survive the trip from Earth to the moon. In fact, there are whole theories about earth being seeded by microorganisms from an asteroid although I consider those pretty far out. But it doesn't get any better by the fact that a) it's coming from a place we know is full of microorganisms, b) space probes travel much shorter, c) land more gentle, d) need radiation shielding and livable operating temperatures. You can read more here [wikipedia.org] about how hard these bastards are to kill. Sending a probe there would be almost as much a medical task (sterilization, contaminant detection, seals) as space travel.
Re:That is some cold water (Score:5, Insightful)
Firstly, sending a self-contained labratory to do experiments there on the moon's surface is sending a probe to the surface of a far-flung moon for remote experimentation, which was the first option mentioned in the snippet you quoted.
Also, note that this in no way removes the chance of contamination, it probably increases the chance. Even though these probes are assembled in clean rooms and every attempt is made NOT to contaminate the probe prior to flight, it's impossible to make sure that the probe is 100% free of earthborn life. Airborne viruses might get caught inside the probe, and could wreak havoc on the alien biology, for instance. Other posts here illustrate the problems of microorganisms, but the problem isn't necessarily that our microbes could taint their microbes; the very probe itself could very well contaminate the moon on its own. Remember, the probe very likely would NOT be chemically inert; it could poison the water that it touches. A probe sitting on the surface of a planet for all eternity will degrade and erode. Obviously this is purely hypothetical, but imagine that part of this probe was lead. If a chunk of lead fell into our drinking water, we'd suffer consequences and eventually succumb to lead poisoning. Lead is poisonous to us to some degree, and we can't be overexposed to it. Well, what is poisonous to extraterrestial life that we're investigating? How do we make sure that there's nothing we leave on that planet that damages the ecosystem?
Alternatively, let's assume that we can send a probe which is totally inert and nonthreatening to the moon's environment. We have the possibility of creating something akin to a artificial reef [wikipedia.org], as life grows around the probe and becomes dependent on it. Are we trying to seed life, encourage life, or study life? Where do we cross the line between letting life grow as it may and interfering with its evolution?
Re:That is some cold water (Score:2, Insightful)
Re:Yeah, sure... (Score:3, Insightful)
It's two-fold.
Everyone has always acted like water in the universe was scarce and Earth had some special circumstances that allowed liquid water to exist.
Also, damned near any conditions where we can find water on Earth, there will be sort sort of life hanging about in the form of one extremophile or another -- no matter the conditions.
The more and varied places you can find water, the more you need to start wondering how likely it could be that, if not there but someplace, maybe the likelihood of life existing elsewhere is less remote than we'd thought.
It's not like we expect to find (intelligent) life everywhere we find a puddle or a block of ice. But the more water we find in different places/conditions, the higher the likelihood we could find life, intellligent or othewise, in a lot of places.
If you start increasing the values of any of the things in Drake's equation (or W.A.G. if you prefer) the more likely it seems you would be to eventually find other intelligent (or at least more evolved than microbes) lifeforms around. Learning more about own own solar system lets us make broader guesses about the range of conditions which could exist out there.
If there's any substance to the belief that life on Earth was seeded from elsewhere, other places could have also been seeded. One just never knows. This is just a reflection of the fact that scientists are more willing to entertain the notion than they were in the past.
Cheers
Re:That is some cold water (Score:3, Insightful)
Accomplishing any of the above would be pretty remarkable, and a success.