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#1 2002-07-06 12:01:23

oker56
Member
Registered: 2002-06-30
Posts: 85

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

I've basically reread Isaac Asimov's "Extraterrestrial Civilizations" since the idea that earth's and hence extraterrestrial civilizations might be rare has been popularized recently in a book titled "Rare Earth", which I have yet to read.  Still, I know most of the big thing's said in "Rare Earth".  After rereading I. Asimov's book which was published in 1979 by the way, I find he hit's on all points covered by the new book "Rare Earth" except that jovian size planet's might get dragged in by friction with the protoplanetary disk dust.  I. Asimov also mentions the oddness of the moon but could not find what that oddness could mean for E.T. civilizations.  At that point he had shaved down the possible E.T.'s down into the 1.6 million point.  Then he shaves it down to 500K because of the possibility of nuclear war.  Because he doesn't know about the jovian planet's problem and that the recent amount of jovian planet's found around or nearer the parent star than the earth's distance, I took 90% of that 1.6 and got about 100K possible civilizations without taking into account the moon problem(that really takes a lot out doens't it!).  Even assuming an unfair half instead of another 90 percent of the 100K, taking half of 100K for the possible civilizations that destroy themselves by nuclear war leaves only 50K.  Not to bad, but consider the more probable taking 90 percent of a 100K because of the improbability of the moon.  That is only 1K left.  Take half of that for civilizations destroying themselves by nuclear war leaves 500.  I'd like to bring in a new factor: having a mars planet to ignite phase two civilization.  Now, some of those 500 E.T's could end up with a mars instead of a moon as their double planet system.  I'm jealous of them!  Still, most will have to contend with a moon instead which means as Zubrin has pointed out that they will have to find another planet rich in carbon's to ignite phase two civilization.  But what is the probability of having another mars?  Let's take another 90% as a worst case scenario.  That leaves us with ~50 possible E.T.'s out there.

Amazing!  We've gone from thinking there had to be zillions of them because there were so many stars out there, to wondering if we'd be the only one's.  Fifty isn't to bad.  Seti is still worth the trouble.

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#2 2002-07-06 16:06:21

Phobos
Member
Registered: 2002-01-02
Posts: 1,103

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

I think a lot of these factors that are brought up to explain the likelihood of any one species creating a spacefaring civilization are logical, but I think it's a big step to start predicting the number of spacefaring civilizations out there when we have very sketchy data on just how many habitable planets would have things like moons to motivate them into space, etc.  Personally, I believe that the universe is teeming with intelligent life considering that there are billions of galaxies out there with billions of stars in them but I'm just very skeptical of these calculations people use to try to put a figure on the number of civilizations out there.


To achieve the impossible you must attempt the absurd

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#3 2002-07-06 16:35:56

oker56
Member
Registered: 2002-06-30
Posts: 85

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

That is obviously a lot of technical discussion, but  untill you or someone else comes up with a technical reason why not to take into consideration these various points, then I think we take them seriously.

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#4 2002-07-06 21:19:50

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

Personally, I believe that the universe is teeming with intelligent life considering that there are billions of galaxies out there with billions of stars in them[/quote:post_uid3]
*Interesting.  I'm inclined to think intelligent life in the universe is an extreme rarity, and that non-intelligent lifeforms are only a bit less rare.  Which is why it is, for me, more the pity that much of [what passes for] intelligent life here on our beautiful garden planet is wasted on wars, racial hatred, petty bigotries, etc., etc.

--Cindy


We all know those Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#5 2002-07-07 03:13:06

Phobos
Member
Registered: 2002-01-02
Posts: 1,103

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

*Interesting.  I'm inclined to think intelligent life in the universe is an extreme rarity, and that non-intelligent lifeforms are only a bit less rare.  Which is why it is, for me, more the pity that much of [what passes for] intelligent life here on our beautiful garden planet is wasted on wars, racial hatred, petty bigotries, etc., etc.
[/quote:post_uid0]

Since it's becoming apparent that planets are very common entities in the universe and that complex organic molecules and even sugar have been detected by astronomers in mere interstellar gas clouds, I think there's a very high chance that the universe is teeming with life.  Intelligent life is probably very rare, but considering how many stars and galaxies are out there I wouldn't be surprised if there's thousands of civilizations spread throughout the entire universe.  But you could be right to that life is extremely rare considering that most life that develops near galactic cores will almost certainly be wiped out by the chaos that happens there.  We're lucky in that we developed near the rim of the galaxy.


To achieve the impossible you must attempt the absurd

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#6 2002-07-08 07:44:33

clark
Member
Registered: 2001-09-20
Posts: 6,253

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

But you could be right to that life is extremely rare considering that most life that develops near galactic cores will almost certainly be  wiped out by the chaos that happens there.  We're lucky in that we developed near the rim of the galaxy.[/quote:post_uid0]

Maybe life can only develop out on the rim, which further reduces the possibility of life or intelligent life.

Then there is the question of how often life "spontaneously" begins. Where and how does life begin? We have yet to create life from inorganic compounds, as is currently believed that life first started- how often are the conditions reached to help this transistion?

If there are intelligent species other than human- how many even care about space?
How many have eyes to behold the night sky? If they only see with by hearing, dosen't that almost preclude them from looking at the universe, and exploration in the same way as us?

How many intelligent species have the life span or technology to help their life span  to make space travel even feasible?

How many intelligent species have the biological constution to survive the radiation or other dangers of space- what if leaving their atmosphere instantly fries them becuase they have no tolerance to radiation?

How many intelligent species develop beyond the stone age, or the bronze age, or the middle ages? Any number of reasons could lock them into this "era" for perputity- we don't know if we just got lucky in regards to developing this far. We have 5,000 years of recorded human history, but it took us hundreds of thousands of years to get there, ON TOP OF the millions of years of biological and social evolution.

How many of these worlds hold predatory animals that would act as a catalyst for evolution to develop intelligence?

How many of these worlds had the planatary development similar to ours which allowed for the formation of hydro-crabons or other sources of cheap and abundant energy which allows them to enter a technological age such as ours? (Oil came from the Dino's- no dino's, less oil)

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#7 2002-07-08 14:47:36

Phobos
Member
Registered: 2002-01-02
Posts: 1,103

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

If there are intelligent species other than human- how many even care about space?
How many have eyes to behold the night sky? If they only see with by hearing, dosen't that almost preclude them from looking at the universe, and exploration in the same way as us?
[/quote:post_uid0]

Interesting thought.  I somewhat subscribe to the idea that few things in the universe are truly unique.  Considering the variety of life on Earth that has developed some kind of organ that is sensitive to light, and since having eyes is very helpful to survival, I don't think it would necessarily be rare for life to develop eyes in some capacity.  These lifeforms might not see light in our spectrum, but they'd probably still have sight.  And if there are beings out there who are at least as intelligent as we are, there's a good chance they'll have scientific curiosity the way we do. 

How many intelligent species have the biological constution to survive the radiation or other dangers of space- what if leaving their atmosphere instantly fries them becuase they have no tolerance to radiation?
[/quote:post_uid0]

It could be possible that most of the life in the universe could be more tolerant of radiation than us.  There's just no way of knowing, but it's possible most life will be at least as tolerant of radiation as we are considering that we spawned in a cushy area of the galaxy.  And there is life on Earth that can thrive in high radiation environments, so I don't think it's out of the question that intelligent life could evolve in high radiation environments. 

How many of these worlds hold predatory animals that would act as a catalyst for evolution to develop intelligence?
[/quote:post_uid0]

Well we know of at least one planet where predators are a common occurance.  There's no reason why it couldn't happen on other worlds. 

How many of these worlds had the planatary development similar to ours which allowed for the formation of hydro-crabons or other sources of cheap and abundant energy which allows them to enter a technological age such as ours? (Oil came from the Dino's- no dino's, less oil)[/quote:post_uid0]

If such life is carbon based, there's a good chance that by time intelligent life arises that can utilize fossil fuels, the fuels will be there.  There might be some kind of impediment that could prevent the development of fossil fuels on certain planets, but going on the assumption that we aren't unique, if it can happen on this planet it can probably happen on others.


To achieve the impossible you must attempt the absurd

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#8 2002-07-08 15:04:37

clark
Member
Registered: 2001-09-20
Posts: 6,253

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

One data point is not enough to establish that we are the norm, for all we know, we are the mother of all universal abberations.

For every reason you can think of that would support that there is more than ONE intelligent species in the universe, I can point how that same reason precludes such a possibility.

I somewhat subscribe to the idea that few things in the universe are truly unique. [/quote:post_uid0]

Humans are... so far. So for all intents and purposes, we are the exception to this rule.

Considering the variety of life on Earth that has developed some kind of organ that is sensitive to light, and since having eyes is very helpful to survival, I don't think it would necessarily be rare for life to develop eyes in some capacity.[/quote:post_uid0]

This may be a function of living on our planet, there is no reason to assume for one second that was is true here is true elsewhere. It's like imagining how people in Africa live based on your living habits.

These lifeforms might not see light in our spectrum, but  they'd probably still have sight. [/quote:post_uid0]

There exsist numerous life forms without sight here on this planet- it is by no measn certain for an alien.

And if there are beings out there who are at least as intelligent as we are, there's a good chance they'll have scientific curiosity the way we do.  [/quote:post_uid0]

Why? They could be completely intelligent but devoid of any true scientific inquiry- there are many "intelligent" humans who display this trait afterall, so why not an entire species?

It could be possible that most of the life in the universe could be more tolerant of radiation than us.  [/quote:post_uid0]

And the opposite could be true just as well- furthermore, maybe we are the only "intelligent" species that is hardened to radiation.

And there is life on Earth that can thrive in high radiation environments, so I don't think it's out of the question that intelligent life could evolve in high radiation environments.  [/quote:post_uid0]

There is a lot that goes into the evolution of intelligence- how in your mind would a highly radioactive environment HELP intelligence evolve? In order to protect itself from radiation, an animal would have to know about the radiation- the radiation would ave to kill the slower, dumber ones, while sparing the smarter one- that's a lot like expecting a snow-storm to be continually discerning on its victims...

Well we know of at least one planet where predators are a common occurance.  There's no reason why it couldn't happen on other worlds.  [/quote:post_uid0]

True, but there is no reason to believe that it does happen on other worlds. Maybe the universe is full of cows and grass.

If such life is carbon based, there's a good chance that by time intelligent life arises that can utilize fossil fuels, the fuels will be there. [/quote:post_uid0]

Please establish how you can come to this conclusion. Your statement also implies that there is a "time-frame" for the development of intelligence (your statement implies sometime after the creation of fossil fuels)- how do you know what that time frame is?

There might be some kind of impediment that could prevent the development of fossil fuels on certain planets, but going on the assumption that we aren't unique, if it can happen on this planet it can probably happen on others.[/quote:post_uid0]

A lack of evidence can only lead us to assume that we are unique. Or we could just simply BELIEVE... but matters of faith are best left up to the individual and should be recognized as such.

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#9 2002-07-09 16:31:30

Phobos
Member
Registered: 2002-01-02
Posts: 1,103

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

One data point is not enough to establish that we are the norm, for all we know, we are the mother of all universal abberations.

For every reason you can think of that would support that there is more than ONE intelligent species in the universe, I can point how that same reason precludes such a possibility.
[/quote:post_uid0]

That could be true, but being that we dont have advanced enough technology to really know what kind of life may exist outside our solar system (i.e. devices that can directly take spectral readings from the atmosphere of extra-solar planets) you can't reasonably assume we are the only ones.  We can't automatically jump to the conclusion that we are unique in the universe.  [i:post_uid0]There's just not enough information to know either way.[/i:post_uid0]  But knowing that that the universe tends to be redudant in everything from the existence of gas planets to the very chemicals we are composed of, I think you could make a tentative argument that we [i:post_uid0]probably[/i:post_uid0] aren't alone.

Humans are... so far. So for all intents and purposes, we are the exception to this rule.
[/quote:post_uid0]

And that could only be because we lack the observational technology to study the universe for signs of life.  There were people after all just a decade ago who thought the existence of planets around other stars were fairly rare and unique occurances in nature until new astromical methods proved them very wrong.  Again we see there's redudancy. 

There exsist numerous life forms without sight here on this planet- it is by no measn certain for an alien.
[/quote:post_uid0] 

True, not a 100% certainty, but it's still possible and probably likely as life on Earth has proved.  Only organisms that live most of their life in darkness tend not to have any kind of sight.  Creature that can react to light are much more likely to survive and outwit competitors on a sunlit world than those that can't.


To achieve the impossible you must attempt the absurd

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#10 2002-07-10 09:01:29

clark
Member
Registered: 2001-09-20
Posts: 6,253

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

We can't automatically jump to the conclusion that we are unique in the universe.  There's just not enough information to know either way.[/quote:post_uid0]

And I agree, which is why we either argument is just as valid. However, if we follow scientific principles, we can only extrapolate from available evidence- to do otherwise is just to add conjecture and theory, which is little more than unfounded belief. The evidence suggests we are the only intelligent life in the universe- there is no evidence that demonstartes this to be untrue.

But knowing that that the universe tends to be redudant in everything from the existence of gas planets to the very chemicals we are composed of, I think you
could make a tentative argument that we probably aren't alone. [/quote:post_uid0]

Just becuase many things are redundant does not mean EVERYTHINg in the universe is. It is a leap of faith. Until there is another example of intelligent life, we can only assume that we are the only one. That is operating from the facts.

And that could only be because we lack the observational technology to study the universe for signs of life. [/quote:post_uid0]

People say the same thing about God- we lack the means to observe, but that is not proof of non-exsistence. You'll have to do better than that or be pigeon-holed as a simple "believer".

There were people after all just a decade ago who thought the existence of planets around other stars were fairly rare and unique occurances in nature until new astromical methods proved them very wrong.  [/quote:post_uid0]

What evidence disproves this statement?: We are the only intelligent life in the universe.

The belief in ET is just that, ET, there is no evidence to support the theory, only guesswork and assumption.

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#11 2002-07-17 14:19:32

Auqakah
Member
From: England
Registered: 2002-07-13
Posts: 175

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

Frankly, trying to figure out how many intelligent species there are in our galaxy is rather like asking, "how many grains of sand on a beach?". Firstly, there is nothing that says life has to develop along our carbon-based lines. Secondly, there is again nothing to say that life must develop on a planet - which widens up the possibilities of intelligent life in space considerably. Thirdly, we have no idea what the exact limits of environment that life can exist in. Many have guessed; but nobody can know for sure.

[b:post_uid0]"'And if there are beings out there who are at least as intelligent as we are, there's a good chance they'll have scientific curiosity the way we do.'   

Why? They could be completely intelligent but devoid of any true scientific inquiry- there are many "intelligent" humans who display this trait afterall, so why not an entire species?" [/b:post_uid0]

I'm guessing, mostly, here, but it seems logical to me that no entire intelligent species is going to be the same, or even alike. Intelligence insinuates the ability to choose to be different to others - without that, a being cannot be classified as "intelligent". Therefore, any intelligent species would have at least [/I]some[i:post_uid0] interest in science, although what they call science could well be very very different to what we call science. Also, survival of an intelligent race - and perhaps even a non-intelligent race - requires some modicum of curiosity, and that is just what science is, at its most basic.

[b:post_uid0] "There is a lot that goes into the evolution of intelligence- how in your mind would a highly radioactive environment HELP intelligence evolve? In order to protect itself from radiation, an animal would have to know about the radiation- the radiation would ave to kill the slower, dumber ones, while sparing the smarter one- that's a lot like expecting a snow-storm to be continually discerning on its victims..." [/b:post_uid0]

Well... If a biosphere developed on a planet that was highly radioactive, then naturally the animals/plants/whatever would have developed under those conditions - they wouldnt need to know about the radiation, their chemical make-up would ensure their survival. Radioactive environments could well make things easier for an intelligent species to develop, as the mutation rate would be far higher, even with a high resistance to radiation. And once intelligence was developed, the species would be at an advantage to us, scientifically, as they would have a highly radioactive environment to study - thus they would most likely be highly specialised in particle physics. I see no reason why intelligent life could not develop [I]anywhere[/i:post_uid0] in the universe, with the exceptions of the most violent portions, whatever they may be. Life, I am sure, can exist in many many forms - probably most of them very different to our own. Perhaps every single form of life in the universe has developed so differently that interaction, and even knowledge of each others existance, will always be impossible - there is simply no way to know until we know that it is not so. But life here on Earth is amazingly diverse, and I somehow think that in all that space out there in our universe, there are beings sitting behind what passes for their computers, discussing this same subject in forums on their version of the internet.  big_smile Wish I had their email address, though......


Ex Astra, Scienta

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#12 2002-07-17 19:16:24

Phobos
Member
Registered: 2002-01-02
Posts: 1,103

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

But life here on Earth is amazingly diverse, and I somehow think that in all that space out there in our universe, there are beings sitting behind what passes for their computers, discussing this same subject in forums on their version of the internet.   Wish I had their email address, though......

[/quote:post_uid0]

I feel the same way.  I think it's possible that every scenario we've talked about in here is possible and co-existant.  There are probably intelligent beings in the universe who have no interest in science, and plenty others who have developed a driving passion for it.


To achieve the impossible you must attempt the absurd

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#13 2002-09-01 22:46:03

PaganToris
Member
From: Exeter,Ca
Registered: 2002-07-17
Posts: 105
Website

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

naw not a good idea to have the cylce reversed becuse then they might be throwing us accross the room or they could be cooking us for dinner smile


ZIGIE ZOKKIE  ZIGIE ZOKKIE OY OY OY
ZIGIE ZOKKIE  ZIGIE ZOKKIE OY OY OY
ZIGIE ZOKKIE  ZIGIE ZOKKIE OY OY OY
if u know what show thats from than where cool smile

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#14 2002-09-18 19:32:33

oker56
Member
Registered: 2002-06-30
Posts: 85

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

Saying intelligent life can take on any form leads us straight back to thinking intelligent life can be on the moon, venus, mars, jupiter, and of all places the sun, but we've clearly found otherwise.  Clearly, the rest of the universe is at least as harsh or more than all those places listed above, so it is instructive to look at the human species as a test case and understand its environment and history as a minimum case.  If you'd look at the various sciences involved in the understanding of life recently, you'd find there's plenty of insight about the nature and hence definition of life and intelligence.  I'd suggest reading thing's about Ilya Prigogine's stable non-equilibrium structures, Maturina's autopoiesis, Manfred Eigen's hypercycles, chaos theory, Lynn Margulus's symbiosis theory.

You people just don't want to take into account the finding's of Isaac Asimov in his "Extraterrestrial Civilization's", and "Rare Earth". 

I am also not amused by the editing of my post.  I do not use smilies, and I did not say anything about Seti being worthwhile.  I will say it is worthwhile as an experiment in parallel processing though.

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#15 2002-09-19 03:06:32

Josh Cryer
Administrator
Registered: 2001-09-29
Posts: 3,830

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

I don't think anyone edited your post. Whenever you use a ! next to a ), the board creates a winky smilie. But maybe that's not that you were talking about...


Some useful links while MER are active. Offical site NASA TV JPL MER2004 Text feed
--------
The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.

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#16 2002-09-19 11:25:14

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

I don't think anyone edited your post. Whenever you use a ! next to a ), the board creates a winky smilie. But maybe that's not that you were talking about...[/quote:post_uid3]
*This is why I use brackets [ ] instead.  Yes, a ; next to a ) will create a wink

Posts cannot be edited except by the person who posted it.  Adrian *might* be able to edit, being the moderator of these message boards, but I *don't* believe he would do that or has done that.  I've seen no evidence of him doing anything of this sort.

--Cindy


We all know those Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#17 2002-09-19 15:56:58

Phobos
Member
Registered: 2002-01-02
Posts: 1,103

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

Saying intelligent life can take on any form leads us straight back to thinking intelligent life can be on the moon, venus, mars, jupiter, and of all places the sun, but we've clearly found otherwise.  [/quote:post_uid0]

Intelligent life probably could take on any form as long as the prerequisite materials and conditions required for life were present.  Earth might be the only place in the Solar System where intelligent life could develop (can't rule out Europa just yet though, who knows what we'll find there) but considering the trillions of stars that exist throughout the universe I just don't see us being alone, especially with all of these discoveries of extrasolar planets pouring in.


To achieve the impossible you must attempt the absurd

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#18 2002-09-19 17:30:51

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

At the risk of labouring the point to death about a "!" followed by a ")" producing a smilie, I've found that if you introduce a space after the exclamation mark before closing the brackets ... (! ) , no problemo!!
                                     tongue


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#19 2002-09-21 12:08:04

oker56
Member
Registered: 2002-06-30
Posts: 85

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

In rereading Jacob Bronowski's "Ascent of Man", I came to think about how throughout human progress, some people move on and others stay behind; so that, while the more advanced civilization is moving forward there are people in the harsher areas of the planet(currently) still going through the old motions. 

As Max Planck said, revolutions of thought don't occur by convincing the old generation, but by the old generation dying off.

Bye, that's all I need to say; i see this conversation will go nowhere.

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#20 2003-03-10 05:34:50

wccmarsface@msn.com
Member
From: Bremerton, Washington
Registered: 2003-03-10
Posts: 12

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

[color=#000000:post_uid0]I have read "Rare Earth: Why Complex Life Is Uncommon In The Universe," by Peter Ward and Donald Brownlee with great interest.  It would seem we have complex life here on the earth for two not insignificant reasons:  first, massive Jupiter is located at just the right spot to keep our cozy little world from getting smacked by Oort Cloud comets at a far greater frequency, and, second, we've got a super-giant moon orbiting our planet which resulted from a most unlikely impact of a Mars-size protoplanet during the formative stages of solar system history; our wonderful moon ostensibly acting as a great stabilizer of the earth's obliquity!  In that light, perhaps our sentience and our civilization is unique in the entire 14 billion year history of the universe!  For me, this is reasonable, but could it really be true that we're it?  Maybe so, or maybe not:  unfortunately, this hypothesis is probably not likely to be amenable to testing, and thus can only remain a somewhat reasonable speculation in lue of real hands on data.  Also, when you look at the data of extrasolar planet hunters like Geoff Marcy and others wherein we typically find gas giants either very close to their parent stars (we're talking other stars similar to our sun, of course) or otherwise in very chaotic elliptical orbits, our very own solar system may be itself a considerable exception from the norm!  It would seem that any alien civilizations that might be out there are exceedingly inconspiquous by their complete absence.:;):[/color:post_uid0]

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#21 2003-03-22 15:43:58

Cobra Commander
Member
From: The outskirts of Detroit.
Registered: 2002-04-09
Posts: 3,039

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

[color=#000000:post_uid0]

I have read "Rare Earth: Why Complex Life Is Uncommon In The Universe," by Peter Ward and Donald Brownlee with great interest.  It would seem we have complex life here on the earth for two not insignificant reasons:  . . .[/quote:post_uid0]
An interesting read, however I would advise also reading "Life Everywhere: The Maverick Science of Astrobiology" by David Darling before formulating a rigid opinion on the matter.[/color:post_uid0]


Build a man a fire and he's warm for a day. Set a man on fire and he's warm for the rest of his life.

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#22 2003-03-23 14:26:11

dicktice
Member
From: Nova Scotia, Canada
Registered: 2002-11-01
Posts: 1,764

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

[color=#000000:post_uid0]With "only" billions of stars out there, thought to be so before Hubble proved they belong to a single galaxy, you might not have got more than reasonable arguments as to our "sentience uniqueness and our civilization" in the entire universe." But...with the billions of galaxies now known to be out there...what foolish, not to mention prideful, presumption![/color:post_uid0]

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#23 2003-03-23 18:43:21

soph
Member
Registered: 2002-11-24
Posts: 1,492

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

[color=#000000:post_uid0]Let's assume that ET is on our level of advancement.

They are confined to one planet and have minimal interplanetary activity.  How would ET find *us*?  Radio waves?  Do we really think that ET, x light years away, is going to pick up on our radio waves? 

How are we supposed to find ET?  We're doing the best we can, but we are trying to find a specific ameba in the ocean.  It's not going to happen.[/color:post_uid0]

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#24 2003-03-23 19:43:45

Josh Cryer
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Registered: 2001-09-29
Posts: 3,830

Re: Extraterrestrial Civilizations - Isaac Asimov's predictions vs"Rare Earth

[color=#000000:post_uid0]The answer to finding ET is “luck.”

I think the real key though, is finding life outside of Earth, and if possible, a large sample. At least then we would know how ‘alone’ we potentially are.  If we can't find life outside of Earth after searching hundreds of the nearest stars, and thousands of planets, then we could arguably give up the search and tag ourselves unique (though I'm sure others would continue searching). If we do find life, of course, and a good sample of it, then we'd be able to create a good probablity (we'd know the conditions where life forms best, what kinds of life are more robust, and so on), and then decide whether or not to continue our search for [i:post_uid0]intelligent[/i:post_uid0] life.

Of course, some would argue that such a search is unnecessary, epecialyl after we've figure out everything about how life forms, were it is, and so on, but certainly the awe of discovering a new intelligent species would still exist.[/color:post_uid0]


Some useful links while MER are active. Offical site NASA TV JPL MER2004 Text feed
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The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.

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