Cassini Could Find Signs of Life on Enceladus 126
New Scientist reviews the possibility that the Cassini probe might be repurposed to look for signs of life on Saturn's enigmatic moon Enceladus. "[Enceladus' water vapor] plume's origin is still being debated, but some models suggest the moon holds an ocean of liquid water beneath its surface. This ocean could be a potential habitat for extraterrestrial life. ... Though the probe was never designed to look for life, it could do so by studying organic chemicals such as methane in the plume, the team says."
Just imagine what could be there (Score:2, Interesting)
Sounds nice but.... (Score:3, Interesting)
1. Design and build rover/robot/probe whose sole task is to find and identify life on another planet/moon/whatever.
2. Deploy said rover/robot/probe.
3. Get definitive answer - Yes there is/yes there was actual life here, or No there isn't/no there wasn't actual life here.
4. Rinse and repeat.
Seriously, why is that so hard?
Extra-terrestrials living in the oceans (Score:3, Interesting)
Extra-terrestrials will taste good with some fava beans, and a nice Chianti.
Re:Sounds nice but.... (Score:3, Interesting)
Re:Just imagine what could be there (Score:5, Interesting)
When people hypothesize about life forming on earth, they mention catalysts such as lightning strikes or volcanoes jump-starting chemical reactions. Not a far stretch of imagination given the thermophilic and cryophilic bacteria here on earth. Unfortunately, I don't think we should expect to find anything profound until we can load ourselves into a rocket, go there ourselves, and hope that we can return and analyze our samples without contaminating them.
Re:Extra-terrestrials living in the oceans (Score:3, Interesting)
Re:Sounds nice but.... (Score:5, Interesting)
How do you know when you've found life?
How do you distinguish between life and unusual chemical reactions?
Sure, if a gnarled humanoid pops up and waves a glowing finger at you, you've found life, but what happens if you just find a brown stain that seems to be producing oxygen? Is it alive or a permanganate salt?
Laughed at in college (Score:3, Interesting)
I wrote a paper in a college astronomy course where I speculated that Enceladus might have life given the water there. I was given a lower grade because of it.
Vindication is sweet.
Re:Just imagine what could be there (Score:5, Interesting)
Re:Laughed at in college (Score:4, Interesting)
The founder of Federal Express allegedly got a "C" for the company's idea outlined in an economics project.
Re:Misleading Summary (Score:3, Interesting)
One downside to the life idea is that some speculate that Enceladus's warm condition may be periodic due to a recent but no-longer-existing orbit arrangement with another moon(s). If this is the case, then the moon may not stay warm long enough for life to get a foothold. While earth life is capable of "hibernating" in frozen conditions between cycles, it probably took a while before it got sophisticated enough to pull such tricks.
Thus, Jupiter's Europa is still the better bet in my opinion because the source of its heat (for liquid water) is known and fairly stable. As I remember it, simulations show that it's tidal friction with Jup and nearby moons is sufficient to generate needed internal melting. This is not the case with Enceladus. It's heat source is still a mystery.
Re:Just imagine what could be there (Score:3, Interesting)
Don't assume life will automatically exist where there is water and light. Just because the conditions for life are there, doesn't mean it's not a massive improbability that it starts. If the start of life was easy, we would have replicated it centuries ago. Personally, I would be very suprised if we see life in our solar system (apart from Earth). I do still hope to be suprised though... but not by a face consuming alien killer virus, obviously.
Re:Just imagine what could be there (Score:4, Interesting)
It's difficult to say whether it's improbable or not. We know that some pretty damned neat chemistry can take place where you have liquid water, complex organic compounds and a good source of energy. There are a number of bodies in the solar system that now appear to have at least the water and energy, and finding amino acids and other organic compounds in cometary bodies is a pretty good indicator that places like Enceladus and Europa probably have their fair share as well. The real difficulty is these worlds have really thick layers of ice, so getting a sample of what's in the oceans beneath would be a trick.
Re:Just imagine what could be there (Score:3, Interesting)
Problem is even bigger - our only data point shows us the place FEW BILLION YEARS after formation of first life here; which greatly affected the environment (presence of free oxygen, carbon cycle in the atmosphere regulating global climate, and so on...).
Therefore, contrary to what you say in your last sentence, we can't assume at all that what is suitable for the formation of life is close to what we have here...simply because conditions on early Earth, when life formed, were so vastly different (and we're not sure EXACTLY what they were...)
Actually, it's fairly safe to assume that, while current conditions on Earth are a good indication of presence of "old" organic life, they might actually hinder birth of new life (excluding memes taking over genes to such a degree that life becomes "technological")