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Saturn moon 'able to support life'

bbc.com

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Re: Saturn moon 'able to support life'

#141

Post by mihaifm »

GlennS wrote: post #53
nostrademons wrote: post #17

Earlier quoted context omitted.

I'm kinda curious if there's any evidence that would support or rule out intelligent life having existed on earth before. I mean, if humanity goes extinct and it's another 65 million years before another intelligent species evolves, what evidence would they have of our existence? All our buildings would've long since crumbled into dust or been crushed by plate tectonics. Metal will corrode and rust away after a few t…

Largest stone monuments gone after 10,000 years? Are you sure? The pyramids are already approaching 5,000 years old. Do they show any signs of disappearing?

If you only take erosion into account, they are likely to last millions of years. If someone takes them apart piece by piece...that's a different story.

Re: Saturn moon 'able to support life'

#142

Post by dave_ant »

Is there tectonics on that moon ? Isn't it too small for that ? The same goes for Europa... Is there real tectonics there ?

If there is no tectonics in place and you have a "closed" big bucket of water constantly filled up with chemicals from hydrothermal vents during billions of years, wouldn't the water become completely soaked and kind of slimy ? Not the best place for life, even for extremophiles...

I also found an interesting article on the probable high acidity of Europa ocean, that would make it not suitable for harboring life : http://www.space.com/14757-europa-moon-ocean-acidic.html

I guess it could also apply to Enceladus ocean. Can someone elaborate on that ?

P.S.: English is not my native language, sorry for any grammatical incoherence :)

Re: Saturn moon 'able to support life'

#143

Post by marktangotango »

beamatronic wrote: post #25
marktangotango wrote: post #7

Earlier quoted context omitted.

Well, deep sea, thermal vent life is predominantly blind on earth at least. One may postulate this form of life is much less likely to form technological civilizations thus moderating such. Thoughts?

Consider the way such life looks to us. It's stuck down there, hampered by its environment. We might look that way to an advanced civilization. "Check out those humans, they're intelligent but they're stuck way down there on the crust of that planet, under all that air, stuck in their gravity well"

That's very true, if earths Gravity was just a bit stronger chemical rockets couldn't even make it to orbit. Like right now we can only get 5 to 10 percent of vehicle mass to orbit, imagine if that where 1 or .001 percent. That would make space exploration incredibly expensive. It's already prohibitive at our level of gravity.

Re: Saturn moon 'able to support life'

#144

Post by Ralfp »

V-2 wrote: post #135
jerf wrote: post #21

Earlier quoted context omitted.

I've thought about this and my conclusion is that we will likely leave behind a very strange pattern of certain natural resources. "Oh, look, here's a vein of copper! It's getting better, and better, and, that's weird, it's gone now and there's a complete break in the strata for some reason." Over time new mountains may form some new deposits, but it may be noticeable in the older mountains (that are today the younge…

That's assuming intelligent life always builds an industrial civilization...

How else could they cope with growing needs for goods or, say, entertaiment as their civilization develops?

Or would you then argue that intelligent life could develop sort of moratorium on further development in line with their value system?

Re: Saturn moon 'able to support life'

#145

Post by blauditore »

gonvaled wrote: post #112

“able to support life“ ... as we know it. The universe being so vast and so diverse, most life forms will probably escape our comprehension: completely different chemistry, environments (pressures, temperatures), time scales, state of matter (plasma based life forms?), or even energy based ones. We are not even looking for such different life forms, since we have already concluded that: - life must be water based - l…

I've recently raised the same questions here, and there are indeed a couple reasons that favor searching for organic life. The short version is:

- Complex structures are likely to require an element with 4 valence electrones, and carbon is the simplest one of them (lowest mass number), which also provides it with better properties like reactivity compared to e.g. silicium

- Hydrogen and oxygen are two of the simplest elements, so probably more likely to exist than anything else with similar properties (if you hear hoof steps, you think of horses, not zebras)

- The only life forms we know so fare are based on organic structures, so we know the requirements if its existence and what to look out for

See my original comment[1] and its replies for more details.

[1]: https://news.ycombinator.com/item?id=13668440

Re: Saturn moon 'able to support life'

#146

Post by nnq »

charles-salvia wrote: post #12
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…

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…

What intuition makes you believe that once you have microbial live + some kind of stability (low levels of ionizing radiation + a decent level of chemical stability, so not too hot), evolution to advanced multicellular organisms is not pretty much the default?

I'd be more or less inclined to believe that once you have the first microbes advanced enough to support cell2cell signaling, and some kind of "condensed blueprint information mechanism" (what DNA is on Earth), the rest of the ring would pretty much be unavoidable, though slow.

Human-level intelligence might be rarer, in that you'd probably need a quite few evolutions to plateau + extinction cycles (think cambrian extinction, dinosaurs' extinction and probably a few others), most likely more than we had on Earth (I's assume we kind of got lucky), probably since what you get to something like "monkey level intelligence", most increases in intelligence would be disadvantageous for survival, unless they happen in a species with a tool-usage-friendly body plan + some pack/social tendency + environment change to challenge them to evolve but not to extinct + "construction friendly solid-ish environment" (I imagine dolphins, squids and octopuses, and most monkeys plateaued because they lacked at least one ingredient of the magic combination, and this tends to be the rule...), but this should pretty much happen.

And then you have the fact that our galaxy should have a few billions or tens of billions of Earth like planets based on what we know (probably more "life friendly" planets if you allow that other chemistries than "carbon + liquid water" could support life), it's pretty much unavoidable that there are quite a few human level species in the gallaxy.

The scary bit it that there should be quite a few above that, that probably went past their first singularity/transcendence event and are no longer constrained by biology and individual mortality and probably dumped their biological bodies long ago... scary being the fact that we don't see any sign of their presence.

Re: Saturn moon 'able to support life'

#148

Post by adrianN »

jumanchiss wrote: post #110
adrianN wrote: post #102

Earlier quoted context omitted.

Animals not being intelligent is also very convenient if the bible teaches that they're made for our use. There are fewer ethical problems if they're soulless automatons without consciousness or intelligent.

Same goes for plants, but i don't see you and all the partisan Vegans (and in this case Anti-christian bigot) care for them, On the contrary, they mock everyone who dare to say that plants are intelligent beings.

From the guidelines:

> Be civil. Don't say things you wouldn't say in a face-to-face conversation. Avoid gratuitous negativity.

Re: Saturn moon 'able to support life'

#149

Post by jordache »

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…

would you be really surprised though?

I've already come to the conclusion that there is/was some sort of life within our solar system.

Intelligent life is much more rare. If there is some evidence of that in our solar system, I would be floored

Re: Saturn moon 'able to support life'

#150

Post by pacman128 »

Cyph0n wrote: post #24
nostrademons wrote: post #17

Earlier quoted context omitted.

I'm kinda curious if there's any evidence that would support or rule out intelligent life having existed on earth before. I mean, if humanity goes extinct and it's another 65 million years before another intelligent species evolves, what evidence would they have of our existence? All our buildings would've long since crumbled into dust or been crushed by plate tectonics. Metal will corrode and rust away after a few t…

How do we know that 65 million years is long enough for a species with a human-like intelligence to evolve? What if our evolution was merely a biological fluke that took much less time than usual?

A common misconception about evolution is that follows a linear progression to higher forms. There is no ladder it's ascending, it's a spreading tree ( http://evolution.berkeley.edu/evolibrary/article/evo_07). It's a system that is exploring a fitness landscape with many local maxima for reproductive success. We have no prove that developing a species with self-aware intelligence is inevitable.
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