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Cassini Finds Evidence of Water
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"
1) Suggest a possible discovery of liquid water out there
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?"
Education is a better safeguard of liberty than a standing army.
Edward Everett (1794 - 1865)
The practicality of sending a probe to the surface of a far-flung moon for remote experimentation or return payload for terrestrial experimentation aside, the worry with such a procedure would be contamination.
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.
All /. comment so far have nothing to do with the news. *sigh* Always the same with astronomy items.
/. posts are just people cracking stupid jokes.
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
Information wants to be anthropomorphized.
It generally has to be pretty clean water, too, at least from what I've observed. We put bottles of filtered water in the fridge here at work all the time, and it supercools - if you're careful, you can drink some nice, below 32F water, but if you shake it up or bump the bottle too much, the water will crystalize into an icy slush. Pretty neat trick. Unfiltered water just seems to freeze solid in the freezer, though.
JRjr
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.
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 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.
Live today, because you never know what tomorrow brings
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, 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?
Apples and oranges. The Galileo Spacecraft was plowed into Jupiter's atmosphere because it wasn't properly decontaminated (not needed for something that stays in space and takes pictures). Equipment that is meant to land and search for life will obviously be decontaminated.
Are we trying to seed life, encourage life, or study life?
Accomplishing any of the above would be pretty remarkable, and a success.