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Saturn moon 'able to support life'

bbc.com

11–20 of 268 posts

Re: Saturn moon 'able to support life'

#11
Just in the last day or so, reporting on some experiment supposedly demonstrating that asteroid impacts on Earth are/were capable of creating the amino acid precursors to RNA.

Yeah, really, this demonstrates nothing, on its own. But, interesting to think about.

Re: Saturn moon 'able to support life'

#12
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 worthless conjecture, of course, but the point is I wouldn't be surprised if microbial life is very, very common.

Re: Saturn moon 'able to support life'

#14
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…

On earth the jump from single celled life to multi celled life was very rapid relative to how long planets can probably support life on average.

The first evidence of multicellularity is from cyanobacteria-like organisms that lived 3–3.5 billion years ago.[5] https://en.m.wikipedia.org/wiki/Multicellular_organism

Now this is a Biofilms ala mats of multi celled organisms so it's hard to draw a clear line based on the fossils. Other contenders are much younger, but even if you use sexual reproduction as the benchmark that's still within the first 3 billion years and earth likely has another 1.75 billion to 3.25 billion years before it gets to hot.

Re: Saturn moon 'able to support life'

#15
post #5

Here's the paper mentioned in the article ... Cassini finds molecular hydrogen in the Enceladus plume: Evidence for hydrothermal processes > Saturn's moon Enceladus has a subsurface ocean covered by a layer of ice. Some liquid escapes into space through cracks in the ice, which is the source of one of Saturn's rings. In October 2015, the Cassini spacecraft flew directly through the plume of escaping material and samp…

A way to remember it is that Enceladus is the snowball with the blue "tiger stripes" on the south pole (grooved vents through which shoot streams of ice crystals [driven by tidal heating along its orbit around Saturn]).

Re: Saturn moon 'able to support life'

#16
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…

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?

So-- there are caveats. A lot of deep sea life are able to see, and it's because deep sea life also generates their own light. It's a way to communicate to mates, and a way to notice prey, and a way to bait smaller predators.

I also think that echolocation has potential to be equal or better to eyesight! Bats and dolphins do great with it, and I think that it's easy to think of echolocation as being a _visual_ stimuli, even though it's not lightwave-based.

I think the biggest hurdle for an underwater sentient species trying to become more advanced is the difficulties with tool-building. Simple stone tools could be made, but it becomes a lot harder to smelt iron and start doing metal-working.

Re: Saturn moon 'able to support life'

#17
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…

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 thousand years. Our largest stone monuments will be gone after 10,000 or so. You'll find occasional fossilized skeletons, but all that would tell future species is that a bipedal mammal with a large brain once existed. Even plastics, the bane of environmentalists, degrade over a couple thousand years.

Probably the only thing we'd see would be a huge mass extinction and an unusually rapid change in the earth's climate. Which we've seen several times in the geologic record already.

Re: Saturn moon 'able to support life'

#18

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'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…

Isaac Arthur has a very interesting video that touches on that specific topic, but with a space exploration angle.

https://www.youtube.com/watch?v=k7fLNvpl0c8

Re: Saturn moon 'able to support life'

#19

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'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…

What about space artifacts? Out in the vacuum stuff corrodes/degrades much slower - would satellites still be around or would they have had their orbits degraded and burned up in the atmosphere? Also, how detectable would the stuff we've left behind on Moon (the mirror, perhaps? Only thing that can probably destroy evidence of our presence on the moon would be asteroid impacts) be to a civilization that doesn't know it's there?

Re: Saturn moon 'able to support life'

#20

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'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…

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