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Saturn moon 'able to support life'

bbc.com

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Re: Saturn moon 'able to support life'

#171

Post by Symmetry »

guelo wrote: post #85
charles-salvia wrote: post #12

Earlier quoted context omitted.

Based on the developments in exo-planet research along with discoveries like this over the past couple of years, I would conjecture that life is ridiculously common. But by life, I mean microbial life. I would imagine that multi-cellular life is much rarer, and life capable of reaching human-level intelligence and beyond is probably absurdly rare, on the level of something like one species per galaxy. It's all worthl…

That is bad conjecture. We have no evidence of life anywhere besides earth, microbial or otherwise. Exoplanet research and this new data has found planets that could conceivably host life, but that's it.

Well, we do have evidence of past life on Mars - just not conclusive evidence. See

https://en.wikipedia.org/wiki/Allan_Hills_84001

and

https://en.wikipedia.org/wiki/Microbially_induced_sedimentar...

And, of course, that's not evidence that there's still life on Mars.

Re: Saturn moon 'able to support life'

#172

Post by [deleted] »

guelo wrote: post #85
charles-salvia wrote: post #12

Earlier quoted context omitted.

Based on the developments in exo-planet research along with discoveries like this over the past couple of years, I would conjecture that life is ridiculously common. But by life, I mean microbial life. I would imagine that multi-cellular life is much rarer, and life capable of reaching human-level intelligence and beyond is probably absurdly rare, on the level of something like one species per galaxy. It's all worthl…

That is bad conjecture. We have no evidence of life anywhere besides earth, microbial or otherwise. Exoplanet research and this new data has found planets that could conceivably host life, but that's it.

[deleted]

Re: Saturn moon 'able to support life'

#173

Post by [deleted] »

andrepd wrote: post #161
yomly wrote: post #158

So here's an orthogonal question. In a field like space navigation, where your findings come back after an expedition planned 5-10+ years ago how do you be "agile"? What is the go to project management style? Can we learn from these disciplines for alternative practices to building software?

Orthogonal? x) Why not "unrelated"?

[deleted]

Re: Saturn moon 'able to support life'

#174

Post by pavel_lishin »

vidarh wrote: post #152
aleksei wrote: post #119

Earlier quoted context omitted.

I get your point, but I posit that this is a very human point of view. Once you've cracked the energy needs for interstellar travel, what's the point of raising a war campaign light years away (especially if you need generation ships to attack)? Furthermore, it doesn't seem very intelligent to me that all capable species just hunker down in their own gravity well to die off unnoticed and without having explored the u…

They wouldn't need generation ships. You "just" need sufficient tech to put engines on a suitable astroid and accelerate it to a decent fraction of c; it only needs enough logic to fine tune the path. An invasion force is horribly inefficient vs. just slamming a lot of mass at someone at high enough speed. And it only takes one massively paranoid, xenophobic species lobbing big rocks at people to ruin the entire neig…

Isn't that only a problem if you're completely planet-bound? If you want to play it safe, you shouldn't put all of your eggs into a single basket anyway.

Re: Saturn moon 'able to support life'

#175

Post by Symmetry »

moomin wrote: post #30
charles-salvia wrote: post #12

Earlier quoted context omitted.

Based on the developments in exo-planet research along with discoveries like this over the past couple of years, I would conjecture that life is ridiculously common. But by life, I mean microbial life. I would imagine that multi-cellular life is much rarer, and life capable of reaching human-level intelligence and beyond is probably absurdly rare, on the level of something like one species per galaxy. It's all worthl…

I'd guess that microbial life would evolve into cellular life almost anywhere there was enough heat.

You need more than heat for life to evolve. You also need a source of useful energy. Probably a long-lasting chemical gradient like you see in undersea vents but there are a number of possibilities. Life has evolved on Earth to use other sources of energy too, most commonly sunlight, but the machinery to use those is much more complex.

Re: Saturn moon 'able to support life'

#176

Post by kerbalspacepro »

adrianN wrote: post #104
hackuser wrote: post #83

Earlier quoted context omitted.

Europa is an extremely tiny target to hit randomly from Earth, probably made smaller by the fact that, in order to hit Europa, the object has to pass near Jupiter without getting pulled into it. On the other hand, there are billions of years of random attempts, as you said.

But there is a big lump of mass near Europa that tends to attract projectiles.

You mean the wormhole with a blackhole on the other side?

Re: Saturn moon 'able to support life'

#177

Post by kerbalspacepro »

andrepd wrote: post #161
yomly wrote: post #158

So here's an orthogonal question. In a field like space navigation, where your findings come back after an expedition planned 5-10+ years ago how do you be "agile"? What is the go to project management style? Can we learn from these disciplines for alternative practices to building software?

Orthogonal? x) Why not "unrelated"?

It is related? The article is about space research, his question is about the management and organization of space research.

Re: Saturn moon 'able to support life'

#178

Post by smdz »

I always had this question - Can life exist outside our perception of biological life?

Intelligent life might be an anomaly, and rare in the universe - but is it possible that life exists outside our perception of biology? Afterall everything is just rules and actions that lead to predictable reactions (unless quantum physics says something else)

I look at artificial life - that exists in virtual environments. It looks like life - but we know it isn't for real. It cannot replicate/grow outside its environment. But that argument could be used to for all non-human life on Earth, if humans never existed.

Even stuff like mars rover could be engineered to mine, manufacture and duplicate - eventually creating a colony of rovers that populate the planet and consume the planet's resources. Well, that might look like semi-intelligent life - but we know it isn't - or is it life?

Re: Saturn moon 'able to support life'

#179

Post by Symmetry »

adekok wrote: post #63
nzonbi wrote: post #4

If life is there, completely disconnected from earth life, it would be dramatic. That would mean that our solar system, has life on at least two, out of nine planets. That would seem to indicate that life is a fairly common things on planets. It would allow to adjust the drake equation, to easily predict millions of planets with life. And that would mean a high probability of many advanced, intelligent civilizations…

> If life is there, completely disconnected from earth life, IIRC (I can't find the reference now), the "dinosaur killer" asteroid would put rocks from Earth into space. With sufficient velocity that they could reach nearby solar systems within 100M years. So from a strictly physical point of view, I would argue that the odds of Earth "infecting" Europa with life in the past 3 billion years are pretty much 100%.

Europa doesn't have an atmosphere and it's laying at the bottom of a pretty steep gravity well, over 10 km/s from Jupiter intercept to the surface. Earth to Mars or vice versa microbial transport is pretty credible and you might even have a dormant cell from elsewhere falling down to Europa in a meteor. But I'm not sure I'd swallow any cell surviving Europa lithobraking.

Re: Saturn moon 'able to support life'

#180

Post by tcfunk »

smdz wrote: post #178

I always had this question - Can life exist outside our perception of biological life? Intelligent life might be an anomaly, and rare in the universe - but is it possible that life exists outside our perception of biology? Afterall everything is just rules and actions that lead to predictable reactions (unless quantum physics says something else) I look at artificial life - that exists in virtual environments. It loo…

Somewhat related - I posed this question to my 4th grade science teacher. She was quick to shoot me down, and I'll never forget it.
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