OT: Extrasolar planets discovered directly

[Slick]

http://www.aip.org/pnu/2005/split/724-1.html

[narf poit chez BOOM]

Ah, it's just a bunch of hot air. http://forum.shrapnelgames.com/images/smilies/laugh.gif

[Slick]

Very punny.

[Arkcon]

So let's go already. Seriously, I want off this rock. Sleeper ships, warp drive, store my brain in a jar -- I don't care how -- just lets go. Some moon orbiting these monster planets has gotta have an environment temperate enough to support an oxygen atmosphere dome. C'mon, probably a half a dozen of you guys can make the trip with me. The first real SE4 colonization.

[Suicide Junkie]

You don't want to colonize near there...

The gas giants are orbiting so close that they are 1000's of degrees, and thus bright enough in the infrared to be seen by the telescope.

[Combat Wombat]

Suicide Junkie said:
You don't want to colonize near there...

The gas giants are orbiting so close that they are 1000's of degrees, and thus bright enough in the infrared to be seen by the telescope.



So summer will be alittle tougher than usual. I agree lets get going.

[Atrocities]

Other planets, but too close to their suns thus making them unihabitable by our standards. I am tell you that there is NO life out there, we are it. (By life I am saying beings smart enough to have evolved or developed technology and or science as we have, but not identical to ours, seprate and unique to their world.) We are folks, and Earth is the only place in our galaxy, rather the only planet we will ever know like it.

A harsh statement, but so far there has been proof provided, physical proof, that there is life out there or other habitable planets like Earth. None. At this point its all specualtion, opinion, assumption, and chance, but no hard core fact. So until there is, I choose to go with just the facts, and those facts say we are alone on a very rare world.

[Slick]

The can has been opened and 1 bazillion worms have just crept through the neighborhood.

[DeadZone]

Only because we cant see them, doesnt mean they arent there http://forum.shrapnelgames.com/images/smilies/happy.gif

[Starhawk]

Meh AT that is the most egocentric view we humans have, I mean for cryin out loud we are in a galaxy of millions of stars within a universe of billions of galaxies to assume we are it in this galaxy alone is rather arrogant.

I mean who says another species HAS to have an earthlike environment or HAS to have our comfort level of hot and cold? For all we know there could be a race out there that LOVES venus like environments or another that LOVES pluto like environments.

Oh and BTW as far as Earth being the only "blue planet" out there that too is foolish to assume because even scientists have said we would not likely see other Earth type worlds with modern technology because of orbit/temperature/reflection and various other technostuff that I don't even have a clue how to explain or understand http://forum.shrapnelgames.com/images/smilies/happy.gif

So if they are right and Earth type worlds would be almost impossible for US to spot then for all we know there is in Earth type right next door to us http://forum.shrapnelgames.com/images/smilies/happy.gif (galacticly speaking of course) and maybe that species HAS developed the tech to spot Earth type worlds.....heck maybe we will to within the next 10-50 years or so.

[Renegade 13]

Think about it for a minute:

Assume there are 10 billion galaxies in the universe (a quite conservative estimate). Assume that each of those galaxies have 50 billion stars each (again, this would be an average since I've heard estimates that the Milky Way alone contains 100 to 500 billion stars).

If those figures were anywhere near correct, that would mean there are 500,000,000,000,000,000,000 or 5 x 10 to the 20th power.

Now assume that about 1/4 of all stars have at least one planet (not sure on this figure at all). That means there's 125,000,000,000,000,000,000 planets in the universe, with 12,500,000 in the Milky Way. Now assume that only 1/100th of one percent of those planets are inhabitable as we define it. That still leaves 1250 inhabitable planets in the galaxy.

And you say there's no habitable planets out there....anywhere!?!?

Remember that a lack of evidence does not constitute evidence itself.

[Randallw]

I saw a documentary a couple of months ago where someone presented his formula. It was along the lines of using the percentage of planets that could hold a livable atmosphere, and the percentage chance of intelligent life and the amount of time life will last before becoming extinct. I seem to recall the final amount was that there are 100,000 possible alien races in our galaxy.

[Slick]

The Drake Equation (http://www.setileague.org/general/drake.htm)

[narf poit chez BOOM]

/me gets a lawn chair, some pop and some sour cream and onion chips and sits back to watch the fireworks.

[Slick]

Indeed. I have the popcorn.

[Fyron]

/me passes out some leftover Viking mead. And some root beer.

[Atrocities]

All I am saying is there is NO PROOF that any other life exsits out there. None what so ever. Nothing, zip ziltch, nodda......We can speculate all we want, but until they toss a dead alien, a real one mind you, onto the slab in front of multiple news crews and the US Government says its the real McCoy, then I will be a believer. Until then, I choose not to be grouped with those that society has deemed crap pot nut jobs, and full blown weirdo's, not say that any of you are such, but lets face it, society takes a dim view toward those who report having seen UFO's.

[Raging Deadstar]

The Way I see it is there must be life out there in the Universe, due to one simple rational thought.

Did the Universe go through all the dam hassle of creating itself just so Only the Human Race could evolve? Billions of Years of creation, destruction, wonders and atrocities just so a bunch of monkeys could expirience a little rock. It's a bit Anti-Climatic in the grand scheme of thing's no?

[Randallw]

Yes but if God doesn't exist (and for the record I'm just playing devils advocate, I do believe in God) then there is no reason for anything. The Universe didn't create itself for any reason. It just developed. There is no meaning to life or reason for existance. Mankind and animals and plants and single celled amoeba are just a product of biology which just happens to be a way that physics works, and that physics just happens to be the way things work. Nature doesn't care a bit what happens. It's not anti-climatic for the simple reason that there is no climax, the Universe is created by a physical event, it exists for a few billion years and then falls apart. We may well be the only life in the galaxy. Just because we, within the whole reach of existance, can think and recognise our own existance doesn't mean there must be other life forms. That said though, I think that the multiverse is so large probability would seem to show that if it happened here it can happen elsewhere. People talk of finding planets capable of producing life, but usually they are stuck only thinking of life as we know it....jim http://forum.shrapnelgames.com/images/smilies/smirk.gif. if there is a 1 in a billion chance of earth like life than there is another 1 in a billion chance for each of the other 999,999,999 possible forms of life perhaps. The end result of which may be that every planet in the multiverse has a form of life that developed and is natural for that planet.

[Raging Deadstar]

Hehe, all valid points Randall.

Maybe i should use tags a lot more often http://forum.shrapnelgames.com/images/smilies/wink.gif

[jfp3]

What would you have thought about Galileo a few hundred years ago Atrocities? And (to the forum), didn't 'they' confirm some chunk of asteroid found in the Arctic had multicellular organisms fossilized within? Probably from an impact with Mars as I recall...

[Raging Deadstar]

jfp3 said:
What would you have thought about Galileo a few hundred years ago Atrocities? And (to the forum), didn't 'they' confirm some chunk of asteroid found in the Arctic had multicellular organisms fossilized within? Probably from an impact with Mars as I recall...



Antarctic it was. And yes that's true, Unfortuantely it isn't reliable evidence due to contamination through Earth's Atmosphere and landing.

I believe NASA's Project Stardust (http://stardust.jpl.nasa.gov/Home.html) is the next step towards proving this. Check out the FAQ section.

[Slick]

*Throws popcorn at RD. When RD spins around with death in his eye, Slick points at Fyron*

*Sits back in his lawn chair to watch the festivities heat up*

[Renegade 13]

Atrocities said:
All I am saying is there is NO PROOF that any other life exsits out there. None what so ever. Nothing, zip ziltch, nodda......We can speculate all we want, but until they toss a dead alien, a real one mind you, onto the slab in front of multiple news crews and the US Government says its the real McCoy, then I will be a believer. Until then, I choose not to be grouped with those that society has deemed crap pot nut jobs, and full blown weirdo's, not say that any of you are such, but lets face it, society takes a dim view toward those who report having seen UFO's.



That is very true, there's no real direct evidence of other life existing out there. But there is a host of indirect evidence. First, there's the sheer number of extrasolar planets out there. So far we've only had instruments capable of detecting (at the extreme range of the instruments) planets that are at the least 10 times more massive than Earth. When more advanced equipment comes online, for example the James Webb Space Telescope which should be launching somewhere around 2010 or 12, it should be able to directly detect Earth-sized planets. Now just because we can't, at this time, detect those Earth-sized plaents, does that mean they don't exist? We can't see them, but we can't see an electron either, can we? We say it exists, but who of you have seen an electron? And yet we all believe they exist, right?

I know it's a really big leap to go from Earth-sized extrasolar planets existing to life being abundant in the universe, but here's another point. Just look at the diversity of life that has developed (or been created) on this chunk of rock. There's organisms like us, oxygen breathing, likes temperatures around 20-25 degrees. Then you have single celled organisms called thermophiles which live at the bottom of the ocean around vents, who live off of hydrogen sulphide, oxygen is poisonous to them (I believe), and who live in temperatures over 100 degrees! A wide range of possibilities, no? Diversity indicates abundance.

The final point: We, as humans, find it difficult to conceive of life that is different from our own. Sure, we may say that it might exist, but do we really believe it? I think that most people think that intelligent life would be humanoid, and exist in the ranges of temperature, gravity, and atmospheric composition that we ourselves enjoy. That just simply isn't true. There's no reason that I can think of to say that life could not take any form. Why can't the super-hot, close-orbiting Jupiter-like planets that have been detected harbour life? It would not be life as we know it, but is there any reason to think that it could not exist there, and be just as much 'life' as we are?

By the way, everything said above is not intended to offend anyone, it's just me arguing for the "side" of the debate that I believe in. No offense intended in any way.

[Fyron]

*erects a sign with a finger pointing at Slick*

[DeadZone]

Lets see

There are billions of species on Earth alone
And thousands of years ago, we thought the world was small and flat, the stars were gods, comets and lightning were signs from said gods, so on and so forth

Our understanding of the universe is far too limited, science is just a theory until proven right or wrong

But personally, I'd prefer us to try and save what we have here before trying to find out whats out there

[NullAshton]

I believe that Earth is the only planet with sentient life in the universe. I don't think that we're going to find any sentient life anywhere else in the universe. Now, other non-sentient life could exist elsewhere...

[Alneyan]

Well, the answer to whether alien life exists or not is quite obvious: just look at Fyron and Narf! Fyron is a proven Vorlon, and have you ever seen sapient mice wielding six-foot tall hammers? Of course not; besides, mice are the true rulers of the universe, and do not hail from Earth.

(What I am really wondering about is how those other lifeforms would think, but that would be another matter, and a bigger can of worms so I will stay quiet. See, you aren't even reading this message!)

[Aiken]

From the point of view of anthropomorphic cosmology, universe was created (and this process is going on) by the collective mind of humanity. Hence the more we argue the nessesarity of extraterrestrial life - the more chances it exists.

In the light of this ...hmm... theory, your, Slick and others, attempts to stand aside of discussion are revolting, since they decrease chance for Small Green Aliens to appear. So give me, please, your popcorn and chair and join this creative (literary!) debate.

ps: they do exist. (+0,0000000000000000000000000000000000001% chance for SGAs)

[Renegade 13]

Alneyan said:
See, you aren't even reading this message!



Really? I don't believe you!

[kerensky]

/me joins party and brings protable popcorn machine. ******* (this is the emoticon for popcorn according to this site (http://www.dwarfnet.com/chat/smileyfaces4.shtml). Here is another smiley site (http://www.computeruser.com/resources/dictionary/emoticons.html). http://forum.shrapnelgames.com/images/smilies/biggrin.gif http://forum.shrapnelgames.com/images/smilies/biggrin.gif/

[Alneyan]

Renegade 13 said:
Really? I don't believe you!



Of course not! Only the Illuminati, and anyone whose initials are WS, would get the true meaning behind my message; for you, they must be mere words of little consequence.

*Smites the closest person watching the spectacle, with a replica of "Narf's Hammer of Smiting +5", and drops the Hammer next to Narf*

[DeadZone]

Alneyan said:See, you aren't even reading this message!



Huh, you said something? http://forum.shrapnelgames.com/images/smilies/tongue.gif

[Randallw]

I once read a short story about Sherlock Holmes. In this story the radio was invented but mankind could not hear any alien messages and there was concern why. It transpired as part of the story that the quantum uncertainty field covering the earth, due to the fact that it was not known if Sherlock Holmes indeed died falling from Niagara falls, meant that no alien messages could get through. Another story was written with proof that he survived. At this the quantum uncertainty field was removed and suddenly we were inundated with alien radio traffic. very wierd book.

[Ron_Lugge]

This looks like a grenade to me...

http://redwing.hutman.net/~mreed/warriorshtm/grenade.htm

[narf poit chez BOOM]

Oh, don't worry. We've had religious discussions and we still like each other.

* PS: Fyron, that package you are holding isn't a bomb. Please shake it a few times for me, please. http://forum.shrapnelgames.com/images/smilies/laugh.gif

[Strategia_In_Ultima]

I sincerely believe in extrasolar intelligent life. There MUST be life out there. I'm not saying that little green (and tall gray) men are here abducting humans (and cows) for medical experiments because I think that is pure male cow excrement, but I am convinced extraterrestrial intelligent life does exist, if not in humanoid form then in silicon-based crystalline form or even energy-based gaseious form or whatever, but there IS intelligent life out there people!

[Raging Deadstar]

Ron_Lugge said:
This looks like a grenade to me...

http://redwing.hutman.net/~mreed/warriorshtm/grenade.htm



Funny Site, thanks.

Nah, I would say it's a bit extreme to call this thread a Grenade. What kind of peaceful utopia forum do you come from? http://forum.shrapnelgames.com/images/smilies/wink.gif Shrapnel here is usually great for mature posters and not the typical internet crowd (As Narf said, the Political and Religious threads do get slightly toasty at times though.) http://forum.shrapnelgames.com/images/smilies/biggrin.gif We have these conversations safe in the knowledge that it won't explode.

But dam, Do you come from the Heaven of Forums? The uBB Of Eden?
Imagines a utopian paradise, long sprawling forests, hills, rivers and lakes. A beautiful almost clear sky, animals graze peacefully. Then the Phong's Head Bar and Grill lot charge through...

[narf poit chez BOOM]

Actually, I think these arguements draw us together.

/me throws some popcorn. 'Boo! Hiss! I want more arguements! What is this, a sewing convention?'

[Renegade 13]

It's kinda hard to have an arguement when, since Atrocities dropped out of the conversation, all the opinions expressed have been agreeing with each other!

[narf poit chez BOOM]

Oh well. It was fun while it lasted. http://forum.shrapnelgames.com/images/smilies/laugh.gif

[Hunpecked]

Certain considerations suggest that the odds of finding a contemporary alien technological civilization in our galaxy are less than we might think. Far from being typical, our solar system may be a very special place:

Only a fraction of star systems are "friendly" to life as we know it. Blue/white giants burn out much too quickly for life to become established on any orbiting planets. Altair, for example, would be a poor prospect, despite its being the (fictional) home of the Krell in the film "Forbidden Planet." Red dwarfs, which I understand are much more abundant than Sol-like stars, have such a narrow "habitable zone" that planets are unlikely to remain within it year-round. Most stars are part of multiple-star systems, most of which will have no habitable zone whatsoever. Planets orbiting single stars that are more variable than our sun may suffer extreme climate variations that make even primitive life unsustainable.

It's been suggested in recent years that Jupiter and Saturn are exactly the right size in exactly the right orbits to sweep up space debris that would otherwise cause much more frequent mass extinctions on Earth.

Planets with more axial tilt than the Earth may suffer yearly climate variations too extreme for "higher" life forms to develop. Supposedly our unusually large (relative to its primary) moon helps stabilize the Earth's axis.

Speaking of the moon, I recall a Larry Niven story based on the premise that the moon facilitated life on Earth by sucking off some of our dense early atmosphere, which otherwise would have made the planet a "greenhouse" similar to Venus. I can't vouch for the scientific validity of this concept. I also recall an article by (I believe) Isaac Asimov in which he suggested that tide pools (the moon again) may have acted as a crucial transition zone in the evolution of air-breathing animals.

Our galaxy may have a "habitable zone" analogous to the zone around a star. Too close to the galactic center, and an otherwise habitable planet may be periodically sterilized by supernovas, radiation bursts, etc. from the relatively dense population of nearby stars or the black hole at galactic center. Too far from the center, and the abundance of "metals" (elements with atomic number above 2) may be too low to produce stellar systems with such life-essential elements as carbon, nitrogen, and oxygen. Depending on the width of this zone, the vast majority of our galaxy's stellar systems may be unsuitable for life on this basis alone.

Life apparently developed on Earth as early as 3.5 to 4 billion years ago, but remained "primitive" until about half a billion years ago. This suggests that under the right conditions the odds of developing life are high, but development of "higher" life forms is much less likely. This idea was used in the film "Mission to Mars", which explained the so-called "Cambrian explosion" of complex life forms as alien seeding.

Some of these ideas (and others) are discussed at

http://www.spacedaily.com/news/life-00z1.html

[Slick]

Don't give up just yet.

[Renegade 13]

Do you know something we don't...?? http://forum.shrapnelgames.com/images/smilies/wink.gif http://forum.shrapnelgames.com/images/smilies/tongue.gif

[Atrocities]

Hunpecked said:
Certain considerations suggest that the odds of finding a contemporary alien technological civilization in our galaxy are less than we might think. Far from being typical, our solar system may be a very special place:

Only a fraction of star systems are "friendly" to life as we know it. Blue/white giants burn out much too quickly for life to become established on any orbiting planets. Altair, for example, would be a poor prospect, despite its being the (fictional) home of the Krell in the film "Forbidden Planet." Red dwarfs, which I understand are much more abundant than Sol-like stars, have such a narrow "habitable zone" that planets are unlikely to remain within it year-round. Most stars are part of multiple-star systems, most of which will have no habitable zone whatsoever. Planets orbiting single stars that are more variable than our sun may suffer extreme climate variations that make even primitive life unsustainable.

It's been suggested in recent years that Jupiter and Saturn are exactly the right size in exactly the right orbits to sweep up space debris that would otherwise cause much more frequent mass extinctions on Earth.

Planets with more axial tilt than the Earth may suffer yearly climate variations too extreme for "higher" life forms to develop. Supposedly our unusually large (relative to its primary) moon helps stabilize the Earth's axis.

Speaking of the moon, I recall a Larry Niven story based on the premise that the moon facilitated life on Earth by sucking off some of our dense early atmosphere, which otherwise would have made the planet a "greenhouse" similar to Venus. I can't vouch for the scientific validity of this concept. I also recall an article by (I believe) Isaac Asimov in which he suggested that tide pools (the moon again) may have acted as a crucial transition zone in the evolution of air-breathing animals.

Our galaxy may have a "habitable zone" analogous to the zone around a star. Too close to the galactic center, and an otherwise habitable planet may be periodically sterilized by supernovas, radiation bursts, etc. from the relatively dense population of nearby stars or the black hole at galactic center. Too far from the center, and the abundance of "metals" (elements with atomic number above 2) may be too low to produce stellar systems with such life-essential elements as carbon, nitrogen, and oxygen. Depending on the width of this zone, the vast majority of our galaxy's stellar systems may be unsuitable for life on this basis alone.

Life apparently developed on Earth as early as 3.5 to 4 billion years ago, but remained "primitive" until about half a billion years ago. This suggests that under the right conditions the odds of developing life are high, but development of "higher" life forms is much less likely. This idea was used in the film "Mission to Mars", which explained the so-called "Cambrian explosion" of complex life forms as alien seeding.

Some of these ideas (and others) are discussed at

http://www.spacedaily.com/news/life-00z1.html



Thank you. You put into word the many things that I have seen that had conviced me that we are a rare accident out side the normal plan of the universe. Thank you. http://forum.shrapnelgames.com/images/smilies/happy.gif

[Atrocities]

I should also point out that we have no direct proof that there isn't life out there, but the evidence at hand makes the likelyhood that there is that much less likely. Also, who is to that the universe itself is not, or is a life form?

Granted we know so very little about the subject that for all intents and purposes we are but single celled ameba's compared to the human body.

[Strategia_In_Ultima]

Hunpecked, you are right about the fact that most planets cannot support human life..... but who says that all life has to be carbon-based and has to exist in an Earth-like environment to survive? I believe that silicon-based life - even intelligent life - will not be very rare, since silicon is IIRC relatively abundant. Also, if these (possibly crystalline) life forms exist, it will be likely that because of their tough physique, they will be able to survive in climates instantly lethal to a human being. For all we know, crystalline life forms exist on Venus. Why shouldn't it exist? What proof is there that silicon-based or crystalline life is impossible on our sister planet? For all we know, we might be in a Galaxy, even a SYSTEM, abundant with life of innumerable sorts! Give me proof that it is impossible for life forms to exist on Jupiter? Gaseous masses perhaps, or even solid life forms in the methane oceans? And to those who say that the pressure there would be too high and the radiation lethal, I say: look at the animals who live at the bottom of oceanic trenches. They survive at extreme pressures, if you take them to the surface they will actually explode. Also, there are microbes known to be able to resist radiation lethal to a human. So IMO there is no good reason why it would be impossible for life to exist even in this very system. It would be life of a kind as of yet unknown to us, but it WOULD be life.

[Renegade 13]

It's all a matter of life as we know it.

[Strategia_In_Ultima]

And then why should we be ignoring life as we do NOT know it? IM(NSH)O this is a VERY bad thing.....

[Renegade 13]

We should not ignore it. But it is difficult to predict the incidence of life in the universe when we do not even know all the viable forms it could take.

[Hunpecked]

Strategia and Renegade make the point that "life" in our galaxy need not be of a sort familiar to us, i.e. carbon-based. This is certainly valid (within the limits of our knowledge), and makes irrelevant any probability calculations requiring Earth-like conditions. Of course it's only natural to look for more-or-less familiar life forms first: we already have one example of a carbon-based ecosystem, but exactly zero examples of any other type.

What forms could "unconventional" life take? I vaguely recall a juvenile science fiction novel which featured Mercurian creatures that resembled ball lightning. Arthur C. Clarke wrote a short story ("Out of the Sun" ???) in which an electromagnetic entity of some sort was ejected from the sun in a solar flare. Silicon seems to be a popular basis for sci fi life forms, probably because of its position just below carbon in the Periodic Table. If I recall correctly the "Horta" of Star Trek fame (episode "Devil in the Dark") was silicon-based.

Nevertheless, silicon is not carbon. As I recall from my prehistoric chemistry classes, silicon's 4 valence electrons are one electron shell "out" from carbon's, giving the elements roughly similar but far from identical chemical properties. For example, silicon does form polymer chains (as the bosoms of countless Hollywood starlets attest), but I've read (I'm no chemist) that these chains don't approach the length and complexity of carbon polymers (DNA, anyone?). Recall also that silicon dioxide is a solid at temperatures that vaporize carbon dioxide. Now some earth organisms (e.g. diatoms, sponges) take advantage of that and use silicon dioxide STRUCTURALLY, but on Earth at least evolution has favored carbon chemistry for life's vital functions, despite the greater abundance of silicon.

Incidentally, as a naive layman I wonder if a detailed study of the ways these creatures build their silica frameworks might suggest how a hypothetical silicon-based life form could "work".

A couple of places on the web with some tidbits about silicon:

http://en.wikipedia.org/wiki/Silicon_dioxide

http://www.webelements.com/index.html (click on the elements)

[Fyron]

There are silicon-based lifeforms on the Earth right now... They are all monerans, nothing complex, but they are out there.

[Hunpecked]

Interesting. I wasn't aware that any Monerans formed silicaceous structures. Protistans, yes. Any references on the web?

[Fyron]

Dunno. It was in a scientific journal of some sort I read several years ago. A quick google turned up this mention to an upcoming book. No idea if this is a reputable site or not, but there it is:

http://www.gsreport.com/articles/art000035.html

[Baron Munchausen]

Whoa... Using silicon in part of their metabolism does not make them 'silicon based' life. Don't monerans have ordinary DNA like every other form of life on earth? Something analagous to DNA but using silicon that forms the core of their entire suite of biochemical processes would be 'silicon based' life. I don't think there is any such thing known.

[Renegade 13]

Hunpecked you make good points. The only problem with imagining the different forms that silicon based life (or, to be honest, life based on anything other than carbon) is that the imagination of humanity is actually limited to a certain extent to what we are already familiar with. We can not imagine what form a silicon based life form would take since we are not familiar to any great extent with silicon-based life-forms. We say life "would/could not exist" in certain situations, but do we really know?

Also, just because life on Earth favored the development of carbon-based life-forms does not mean that another planet, with similar metallic ratios would not favor another, totally different approach to forming life.

And all of this leaves out the idea of a supreme being (God). If, as some believe, the universe was created, then God could have created whatever forms of life based on whatever elements he wanted to. But I think that's all I'll bring religion into this thread, as we all know that religious discussions can quickly degenerate.

[narf poit chez BOOM]

We would simply have to try to construct a silicon-based ecosystem, down to the molecular level.

It would simply take a while. http://forum.shrapnelgames.com/images/smilies/laugh.gif

[DeadZone]

We've already discovered organisms that live and breed in acid pools (something like that anyway)

So the theory that all life must be Earth life (ie. oxygen & water) has already been proved false
Oh and too the fact that planet life consumed Carbon Dioxide, means that a Carbon Dioxide planet could easily support some form of life

There is no doubt in my mind that life can exist out there, its just a case of whether sentient life has yet to develop out there that I wont make up my mind until its proven either way

[Strategia_In_Ultima]

Perhaps silicon beings don't have such complex and long polymer chains and therefore are simpler, but this does not mean that they cannot be alive. Perhaps their "DNA" length is as long as a human's, but simply cut up into much more small pieces - chromosomes, anyone?

And silicon isn't the only element in the periodic table next to carbon. I'm utterly terrible at chemistry (or science in general), but I think that to support life the building blocks don't need to posess similar properties as carbon. For all we know, there might be iron-based life forms out there debating whether or not carbon-based life is possible.

And if carbon-based life does exist, why does it have to be Earthlike carbon life? Diamonds are carbon, why couldn't there be diamond-like beings out there? Carbon-based yet totally different from Terran life. And even if it looks like Terran life, what criteria are there save for oxygen-breathing, water-needing creatures? Plants breathe carbon dioxide, yet are still considered Terran life. And if we compare Terran life forms, are they so alike? What are the similarities between, say, a stag deer and a clump of moss? An elephant and an oak tree? A Bengal tiger and an amoeba?

[DeadZone]

Typical, my email server has just gone down, meaning if its not back up and I do get in, the email will bounce, and I will most likely loose my spot

Why do computers have to stop working when you want them the most

[Strategia_In_Ultima]

HUH what are you talking about? This is a discussion about extrasolar life forms.....

oh but if your e-mail server is giving you problems you can open a Hotmail account temporarily and change your email adress in your profile to that adress until your original email account is back. That is, if you're talking about your account here..... otherwise, you could also open the hotmail account anyway and forward all the mails you want to keep, contacts etc. there.

[Renegade 13]

I believe he's talking about a beta test spot, if he gets one. The email notification would bounce.

[Hunpecked]

Fyron,

Thanks for the link. I thought your post was about silica structures secreted by certain prokaryote cells, but I see that the link actually refers to Dr. Tom Gold's (so far unconfirmed) speculations on the existence of true silicon-based organisms on Earth. Dr. Gold's book was indeed published in 1999; I found a review here:

http://www.findarticles.com/p/articles/mi_m2120/is_6_80/ai_56022636

Unfortunately, none of the reviews I read mentions any discussion of silicon-based life. The focus of the book is Dr. Gold's theory of a deep underground biosphere supported by an abundance of hydrocarbons (oil and gas) left over from the formation of the Earth (i.e. of non-biological origin). Of relevance to our forum discussion is his suggestion to look for extraterrestrial life BELOW the surface of such bodies as the moon, Mars, and Saturn's moon Titan.

[Hunpecked]

We've already discovered organisms that live and breed in acid pools (something like that anyway)

So the theory that all life must be Earth life (ie. oxygen & water) has already been proved false




Well, even the creatures that exist under (for us) extreme conditions on Earth are still based on carbon, water, nucleic acids, etc. In other words, they're variations on a theme, but not a new theme.


There is no doubt in my mind that life can exist out there, its just a case of whether sentient life has yet to develop out there that I wont make up my mind until its proven either way



As long as even a little corner of the universe remains unexplored, the existence of alien life/sentience can't be disproven. So despite the skepticism of some, an enthusiast for ET's can only be proven right, never wrong. http://forum.shrapnelgames.com/images/smilies/wink.gif

[Hunpecked]

Also, who is to that the universe itself is not, or is a life form?




I recall a line from Carl Sagan's "Cosmos" series on PBS many years ago: "We are a way for the universe to know itself." Since we (and possibly other intelligent species) are part of the universe, then in a sense the universe itself is alive and sentient.

Or maybe just alive... http://forum.shrapnelgames.com/images/smilies/biggrin.gif

[DeadZone]

Renegade 13 said:
I believe he's talking about a beta test spot, if he gets one. The email notification would bounce.



Yea, it posted into the wrong bloody thread, forum plays up for me sometimes

[Hunpecked]

Perhaps silicon beings don't have such complex and long polymer chains and therefore are simpler, but this does not mean that they cannot be alive.



Well, "simpler" is a complex concept when it comes to alien life. If silicon-based life is unable to mimic carbon's complicated polymers, the required chemical "workarounds" might be extraordinarily complex. As a layman I can't even begin to think about the chemical gymnastics required...I think I'm getting a headache. http://forum.shrapnelgames.com/images/smilies/Sick.gif


but I think that to support life the building blocks don't need to posess similar properties as carbon.



Which would render useless just about all of our current knowledge of life. To imagine non-carbon life we'd have to start from first principles, e.g. what chemical structures could/would our chosen element(s) form to reproduce, react to stimuli, evolve...? (My head hurts more.)


For all we know, there might be iron-based life forms out there debating whether or not carbon-based life is possible.




See below.


Plants breathe carbon dioxide, yet are still considered Terran life.



Green plants also consume oxygen, just like we do, though they're net oxygen producers. BTW, one gets a real sense of our place in the universe by remembering that we survive only by breathing plant excrement. http://forum.shrapnelgames.com/images/smilies/eek.gif


What are the similarities between, say, a stag deer and a clump of moss?



Strangely enough, I understand that the genetic differences are smaller than one might think. Note also that they're similar enough chemically that they both survive in the same overall environment (a North American woodland, say) and the deer can even eat the moss.

Returning to iron and silicon as building blocks of alien life, I'm actually kicking myself here for overlooking popular scifi "silicon-based" lifeforms that actually seem quite plausible: mechanoids (droids, robots, automata...). So far our own efforts in the areas of AI and self-directing automata are fairly primitive, but we're far enough along to envision far more sophisticated forms worthy of the adjective "alive". Although it's hard to imagine how mechanical "life" could develop on its own, we already know of one carbon-based lifeform that may some day give rise to such "iron-based" life. http://forum.shrapnelgames.com/images/smilies/biggrin.gif