# Chances of finding extraterrestial life improved?



## Vertigo (Sep 27, 2016)

New confirmation of plumes of water erupting from the surface of Europa has been obtained with another 'sighting' from Hubble. It is encouraging for the prospect of finding signs of life there as it offers the possibility of a mission flying through these plumes and sampling them.

Europa moon 'spewing water jets' - BBC News

I think this is both exciting and scary. If we could sample these jets for microbes, or even just carbon compounds, then it would be the first time we have really tested liquid water for life anywhere other than Earth (Cassini, which 'tasted' water plumes over Enceladus, was not equipped to check for life). On Earth we have found life pretty much anywhere there is liquid water. So finding life, or not, on Europa would have a huge impact on things like the Drake equation.

If there is life on Europa then I think it would be reasonable to expect to find it almost anywhere there is water. If there isn't then it would massively reduce expectations of finding the galaxy teeming with life.

Both Nasa and ESA currently have future missions planned to visit Europa so I would expect them to factor this into their plans.


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## Brian G Turner (Sep 27, 2016)

As the _New Scientist_ piece pointed out, it would certainly be easier than trying to drill through the icy surface for a sample!

But then, here's a thought - if bacteria are being ejected into space via these liquid water jets, then immediately we have a natural mechanism for panspermia to occur. So long as those bacteria can survive travelling through space - which is supposedly common - then any life that evolved on Europa should also potentially spread to any nearby bodies.

In which case - following that argument - the entire Jovian system might not simply show evidence of life, but evolutionary speciation not entirely dissimilar in principle to that demonstrated across the Galapagos islands...

And that's just sticking with Jupiter, and presuming no wider dispersal...


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## Vertigo (Sep 28, 2016)

I'm not sure whether the plumes will be at escape velocity for Europa?

But I think more realistically what they are hoping to detect are organic compounds that might be indicative of life. I suspect having a remote probe be able to actually determine that they are microbes of some sort is a little optimistic; that would probably require samples to be brought back to Earth. Or maybe they'd only risk bringing them back to Earth orbit


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## Stephen Palmer (Sep 28, 2016)

I really hope I live to see the end result of all this, and Enceladus too. It's kinda the ultimate question, yet on our doorstep...


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## Vertigo (Sep 28, 2016)

Stephen Palmer said:


> I really hope I live to see the end result of all this, and Enceladus too. It's kinda the ultimate question, yet on our doorstep...


I agree but at the same time I almost dread the results: if both come back negative then that really would be scary in a very lonely sense!


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## Stephen Palmer (Sep 28, 2016)

Vertigo said:


> I agree but at the same time I almost dread the results: if both come back negative then that really would be scary in a very lonely sense!



True... but it would be nice to hear something positive!

I myself have never been a supporter of the 'humanity will blow itself to bits' theory of the future, I think we're far more likely to survive on balance. So I suppose we'll find out eventually!


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## Nick B (Sep 28, 2016)

I agree Stephen. I think we will survive as a species. 
It is an exciting time. And Vertigo is right, either result is scary. Though if it is negative, that doesn't rule out life in better conditions elsewhere.
I hope for a positive find, because that would surely make a huge impact on future exploration, maybe it is the catalyst that would truly send us out into the stars. Not just 'maybe theres life' but 'there is life, lets go and find it!'


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## Stewart Hotston (Sep 29, 2016)

It seems pretty unlikely to me that we'll find much life out there. I'll be proper shocked if there's life in the water plumes.

Then again, it's about defining life isn't it. Adrian Tchaikovsky has an excellent short on this in the 2nd Solaris book of Sci Fi where he takes on the idea that inorganic substances with specific characteristics could (im)plausibly meet all the generally accepted criteria for life. It's a great little tale.

For me it's remotely possible that we'll discover evidence of very basic life forms elsewhere but I tend to hold the view that we're it within the reach of all our possible tech, that there's nothing within meaningful distance of earth that we'd see as alive or, taking it further, advanced. There are too many practical obstacles for life to be abundant. Gamma ray bursts and all their myriad kin, stable systems, time, debris, suitable planets, suitable companion moons/planetoids, gravity, abundance of the right elements, Fermi's Paradox and the presence of what are probably multiple Great Filters.

However, as my own little counterfactual to this I also think that if we could find life elsewhere within the solar system it would point out the likelihood of life being ubiquitous throughout normal matter space (i.e. not countenancing dark matter). 

As for whether we'll survive as a species. I'm not sure what this even means - we've only been here a blink of an eye in cosmological time. We're unlikely to last another blink - even if we can sort out our own issues we'd then have to survive an environment that is, to put it bluntly, not well disposed to sacks of meat moving around of their own volition.


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## Vertigo (Sep 29, 2016)

Stewart Hotston said:


> It seems pretty unlikely to me that we'll find much life out there. I'll be proper shocked if there's life in the water plumes.
> 
> Then again, it's about defining life isn't it. Adrian Tchaikovsky has an excellent short on this in the 2nd Solaris book of Sci Fi where he takes on the idea that inorganic substances with specific characteristics could (im)plausibly meet all the generally accepted criteria for life. It's a great little tale.
> 
> ...


Sadly I'm largely in agreement with you. My personal suspicion is that life or at least complex life faces so many problems that I think it is likely to be far less common that many people (including myself) hope. And the section I highlighted is more or less exactly the point I made. If we find other life in the solar system then I think we're likely to find it almost anywhere we find water and if we don't then I suspect it's going to prove to be quite rare. In fact it's not impossible to conceive that we could be unique...


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## Stephen Palmer (Oct 2, 2016)

Those of you interested in the development of complex life (and the statistical chances thereof) might be interested in a very good book called _Secret Chambers_ by Martin Brasier. Highly recommended.


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## Stewart Hotston (Oct 4, 2016)

Vertigo - I harbour the same suspicion that we might just be unique...it's a weird feeling. Statistically there's a good case for it that gets lost in the 'Contact' argument of 'it'd be a big waste of space'.


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## Justin Swanton (Oct 4, 2016)

Anyone seen *this movie*? Interesting speculation on the subject.


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## Mirannan (Oct 4, 2016)

Stewart Hotston said:


> It seems pretty unlikely to me that we'll find much life out there. I'll be proper shocked if there's life in the water plumes.
> 
> Then again, it's about defining life isn't it. Adrian Tchaikovsky has an excellent short on this in the 2nd Solaris book of Sci Fi where he takes on the idea that inorganic substances with specific characteristics could (im)plausibly meet all the generally accepted criteria for life. It's a great little tale.
> 
> ...



My take on the "life on Europa" issue:

How significant such a find would be depends (IMHO) on the details. If its chemistry is much like that of Earth life (DNA using the same bases, using the same coding scheme, same amino acids used, same chirality) then its significance is limited with regard to life in other solar systems. Why? Because it is at least conceivable that life could be spread around the Solar System by rocks blasted off the surface of a life-bearing world by meteor impacts, or by spores being spirited away from the high atmosphere of such a world. (There are quite a lot of meteorites from Mars around on Earth, for example.) And so, such life would not be evidence of the probability of life formation.

However, if the chemistry of Europan life is significantly different then it means that life independently arose on Europa. And that matters a very great deal, because moons like Europa are probably very common in the Universe. After all, there are at least three and maybe four in the Sol system. These are Europa (duh!), Ganymede, Enceladus and maybe Titan. Titan is an interesting case, because it's quite possible there is a significant subsurface ocean and there is also an environment on the surface which could conceivably engender life - of wildly different chemistry from ours, obviously.

And that might mean a world, right on our backdoor (cosmically speaking!) with not one but two life systems, of radically different chemistry. The significance of such a find is obvious.


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## mosaix (Oct 4, 2016)

Stephen Palmer said:


> I really hope I live to see the end result of all this, and Enceladus too. It's kinda the ultimate question, yet on our doorstep...



Me too. The older I get the more I realise that I won't be around to see the answers to some of the most intriguing questions. I'm 70 now so NASA, ESA and the rest had better get a move on. I reckon they've / I've got about 25 to 30 years (I hope).


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