This is huge: *current* liquid water on Mars.

[Cavebear]

Speaking of habitability elsewhere -- models suggest multiple ways that Proxima Centauri b, even though tidally locked, could be habitable.

Needless to say, they had to assume an atmosphere and an ocean (nearly a given before postulating any sort of life).  What's interesting is that if Proxima Centauri b does have them, there are multiple ways a stable, habitable environment could exist on a tidally locked world with an eleven-day "year", ranging from a ring of habitability between the too-hot area with Proxima perpetually at zenith and the too-cold dark side, to a dynamic water world with sufficient convection to keep at least some of the dark side warm enough for habitability.

A whole new take on "The Twilight Zone", but one that actually offers possibilities.  The more we learn about possibilities for life, the more likely life exists elsewhere.

I don't necessarily mean intelligent life.  Alien life could well be all microbial pond scum.  The advance to intelligence might well be nearly impossible for all we know. 

But if it gets beyond that, it means conditions allow for evolution and then I suspect it is unstoppable towards intelligence.

[Cavebear]

Why can't something like Gaia be acknowledged to exist (if it does) without having to be worshipped? Why this emphasis on worship?

I generally accept that some general aspects of the planet are somewhat self-regulating.  But I don't accept any INTENT OR DELIBERATE ACTION in that.

[Baruch]

I generally accept that some general aspects of the planet are somewhat self-regulating.  But I don't accept any INTENT OR DELIBERATE ACTION in that.

I agree.  But then I don't worship Mother Earth.

[Baruch]

I worship nothing, since nothing is the only thing worthy of my worship.

Nothing (vacuum of space) is bigger than anything else ... so you are its bitch.

[Baruch]

Is nothing sacred?

Missed the sarc tag.  Nothing around here is sacred.  We are the gang to TP the universe in juvenile delinquency.

[Baruch]

It's the false vacuum, baby! ;-)

See, even nihilism is a damn lie!

[Baruch]

I generally accept that some general aspects of the planet are somewhat self-regulating.  But I don't accept any INTENT OR DELIBERATE ACTION in that.

Homeostasis is usually a sign of living things.  Humans tend to take self-regulating systems and smash them.  I don't know if our destruction of the environment is intentional or not.  Are monkeys sophisticated enough to have "intention"?

[trdsf]

Is nothing sacred?

Only cows, and they make the best holy hamburgers!

[trdsf]

A whole new take on "The Twilight Zone", but one that actually offers possibilities.  The more we learn about possibilities for life, the more likely life exists elsewhere.

I don't necessarily mean intelligent life.  Alien life could well be all microbial pond scum.  The advance to intelligence might well be nearly impossible for all we know. 

But if it gets beyond that, it means conditions allow for evolution and then I suspect it is unstoppable towards intelligence.

Mmm, I don't know.  I think it more likely that life is simple and that intelligent life is difficult.  I judge the first part of that on two observations: one, that life arose quite quickly after the Earth cooled enough to have liquid water -- maybe half a billion years -- and two, everywhere we look (on Earth, anyway) that has the barest minimum requirements for life -- an energy source and a solvent -- has something living in it, even in places that barely 20 years ago, most biologists would say no way.

I judge the second part on a few more observations.  One, the only example we know of intelligenceâ€"usâ€"took a hella long time to evolve.  Even though simple life arose quickly, it stayed very simple for a very long time, something like three billion years.  All the big beasties are quite recent, relatively speaking.  And it took almost another half billion years to get to something that was even just on the starting path to intelligence, much less to an advanced technological society.  All human history, culture and advancement isn't even the barest hair's breadth compared to the history of all life on Earth.

Two, to quote Enrico Fermi, "Where is everyone?"  If intelligent life were easy, there should be many intelligent species older than ours just in this galaxy, and if we've gotten as far as we have in around ten thousand years, imagine a civilization that's been at it for fifteen thousand, twenty thousand, a hundred thousand, a million years.  Assuming by the principle of mediocrity that we are much more likely to be average than we are to be especially advanced or especially behind, if there were a lot of intelligences out there, we'd expect many would be ahead of us and a few of them far ahead of us.  One or two of them with a million years head start on us has already had enough time to have explored the entire galaxy certainly both by probe and directly, even sticking to the speed of light.

And three, large brains are biologically expensive.  Evolution is a lazy process -- if there's an easier way to exploit an environmental niche than brute intelligence, we can expect the easier solution to be the one selected simply because it's the one most likely to be stumbled across.

I don't like the word 'lucky', but it may be that intelligence requires a couple "lucky" breaks in order to happen: an environment best mastered through intelligence rather than instinct and a species scratching at the door of sapience but not quite there yet, at the same time.  So I think it much more likely that life is common, but intelligent life is rare and not at all inevitable.

[Cavebear]

Mmm, I don't know.  I think it more likely that life is simple and that intelligent life is difficult.  I judge the first part of that on two observations: one, that life arose quite quickly after the Earth cooled enough to have liquid water -- maybe half a billion years -- and two, everywhere we look (on Earth, anyway) that has the barest minimum requirements for life -- an energy source and a solvent -- has something living in it, even in places that barely 20 years ago, most biologists would say no way.

I judge the second part on a few more observations.  One, the only example we know of intelligenceâ€"usâ€"took a hella long time to evolve.  Even though simple life arose quickly, it stayed very simple for a very long time, something like three billion years.  All the big beasties are quite recent, relatively speaking.  And it took almost another half billion years to get to something that was even just on the starting path to intelligence, much less to an advanced technological society.  All human history, culture and advancement isn't even the barest hair's breadth compared to the history of all life on Earth.

Two, to quote Enrico Fermi, "Where is everyone?"  If intelligent life were easy, there should be many intelligent species older than ours just in this galaxy, and if we've gotten as far as we have in around ten thousand years, imagine a civilization that's been at it for fifteen thousand, twenty thousand, a hundred thousand, a million years.  Assuming by the principle of mediocrity that we are much more likely to be average than we are to be especially advanced or especially behind, if there were a lot of intelligences out there, we'd expect many would be ahead of us and a few of them far ahead of us.  One or two of them with a million years head start on us has already had enough time to have explored the entire galaxy certainly both by probe and directly, even sticking to the speed of light.

And three, large brains are biologically expensive.  Evolution is a lazy process -- if there's an easier way to exploit an environmental niche than brute intelligence, we can expect the easier solution to be the one selected simply because it's the one most likely to be stumbled across.

I don't like the word 'lucky', but it may be that intelligence requires a couple "lucky" breaks in order to happen: an environment best mastered through intelligence rather than instinct and a species scratching at the door of sapience but not quite there yet, at the same time.  So I think it much more likely that life is common, but intelligent life is rare and not at all inevitable.

Well, I agree so much that you could have actually quoted a previous post of mine (don't worry, you didn't).  But I agree that much.   I suspect microbial life is relatively easy but advancement from there is hard.  But when it does take that first step to advancing ...

BOOM!  No stopping it locally.  Oh maybe a bad day with a gamma ray burst or planetoid intersecting you, but that is rare enough generally so most places life starts will continue.   The game is "if and when" competition starts. 

And how often that occurs we simply will not know until we find some planets where life starts and advances or not.

[Baruch]

Life is easy, if you don't have to work for a living.

Intelligence is hard, see Atheistforums.com.

[Gawdzilla Sama]

"where is everyone"? Maybe billions of light years away, and millions of years in the past or future. Fermi booted that one, he assumed that aliens would be interested in us, could get to us, and would get to us. All assumptions without basis in fact.

[Cavebear]

"where is everyone"? Maybe billions of light years away, and millions of years in the past or future. Fermi booted that one, he assumed that aliens would be interested in us, could get to us, and would get to us. All assumptions without basis in fact.

It is entirely possible that there simply is no viable method for traveling interstellar space in the time that the planets will exist.  That might be a good thing.  I'm not sure I would really want beings like us 1,000 years advanced to find us.

[Gawdzilla Sama]

It is entirely possible that there simply is no viable method for traveling interstellar space in the time that the planets will exist.  That might be a good thing.  I'm not sure I would really want beings like us 1,000 years advanced to find us.

Yerp. They'd squish us and set the dolphins up with robotic arms. (And you read The Dolphins of Pern?)

But realistically, if they checked on Earth every billion years and found cyanobacteria the dominant life form, they'd be back in about 600,000,000 years for another look. Distant descendants of racoons would meet them just outside Neptune's orbit, to explain that they didn't do that.

[Cavebear]

Yerp. They'd squish us and set the dolphins up with robotic arms. (And you read The Dolphins of Pern?)

But realistically, if they checked on Earth every billion years and found cyanobacteria the dominant life form, they'd be back in about 600,000,000 years for another look. Distant descendants of racoons would meet them just outside Neptune's orbit, to explain that they didn't do that.

Was that part of the 'Uplift' series?  I have about 60' of paperback sci-fi books (and more in boxes), so it is hard to remember all the titles.

For "after us", I might bet on bears, but raccoons hold promise.  And don't discount octopi if they ever learn there is something above sea level.

'Breed To Come' had good arguments for cats, too.

If we don't last, probably not other primates either.