Astronomy Common Knowledge Quiz.......
Quizzes & Puzzles2 mins ago
Panspermia And Directed Panspermia
You can use this thread instead, Naomi.
Panspermia is the theory that life is common throughout the Universe, found particularly in Asteroids and the like, so that planets with the right conditions can develop life when an asteroid carrying the raw materials crashes into it -- or in to a neighbouring planet. So far, so reasonable, although as yet there is no conclusive evidence. Still, it seems to make some sense if you believe that life on Earth was likely not a one-off event in the Universe.
Directed Panspermia is slightly different, that life on this planet is the deliberate consequence of some other intelligent being wanting to set it up. Alternatively it's the name for the process whereby Humans can spread life from this planet around the Universe before we eventually die off. The last is controversial on a sort of "Prime Directive" ground (what about life which may already be out there?); the first because it seemingly lacks evidence and anyway doesn't solve the problem of how [i]that[] intelligent life emerged. Just passes the buck, so to speak.
Francis Crick was an early advocate of this theory, although he has since apparently retracted it:
Crick, F. H.; Orgel, L. E. (1973). "Directed Panspermia". Icarus 19: 341–348;
http://
But when I noted this in another thread Naomi leapt to the defence of the theory, though "that was not the place".
Hence this thread, so that it can be more fully discussed.
Panspermia is the theory that life is common throughout the Universe, found particularly in Asteroids and the like, so that planets with the right conditions can develop life when an asteroid carrying the raw materials crashes into it -- or in to a neighbouring planet. So far, so reasonable, although as yet there is no conclusive evidence. Still, it seems to make some sense if you believe that life on Earth was likely not a one-off event in the Universe.
Directed Panspermia is slightly different, that life on this planet is the deliberate consequence of some other intelligent being wanting to set it up. Alternatively it's the name for the process whereby Humans can spread life from this planet around the Universe before we eventually die off. The last is controversial on a sort of "Prime Directive" ground (what about life which may already be out there?); the first because it seemingly lacks evidence and anyway doesn't solve the problem of how [i]that[] intelligent life emerged. Just passes the buck, so to speak.
Francis Crick was an early advocate of this theory, although he has since apparently retracted it:
Crick, F. H.; Orgel, L. E. (1973). "Directed Panspermia". Icarus 19: 341–348;
http://
But when I noted this in another thread Naomi leapt to the defence of the theory, though "that was not the place".
Hence this thread, so that it can be more fully discussed.
Answers
Naomi, I can see from your posts that you are predisposed to the idea of some earlier intelligence whether native or alien but as I said earlier there is no evidence to support these ideas. Most of the 'evidence' is just speculation. What may to us look like a rocket in a primitive drawing probably was intended to represent something entirely different. Other...
19:32 Wed 15th May 2013
@Jomifl @Jim - Thanks for the responses.
I am still not entirely sure I fully understand the time scale over which planets could have formed earlier than our own, because that planetary formation - at least for a planet like ours, requires the presence of very large quantities of those heavy elements, such as Iron and the like, that are present within the Earth and indeed within its core.
So - The Earth forms 4.5 billion years ago, give or take a decade or so :) Universe formed around 14 billion years. Thats a difference of 10 billion years - but of that 10 billion years - how long did it take for other star systems to accrete out, form a sun, for planets to form? How much of that 10 billion years would be needed to give time for sufficient supernovae to have happened in order to create the vast quantities of, say, elemental iron needed to form earths core?
As for life itself - well we often talk about the length of time it took for life to become established on earth itself - estimates being what? around 1 billion years or so for the conditions to become right - and then we have the actual timeline of development of life from single celled organisms to complex creatures like humans. And within that timeline, we see Extinction Level Events - such as the meteor strike at Chixalub - to which the demise of the dinosaur is attributed. Such Events are often seen as having a retardation effect on the development of complex life like humanity - but they could be seen as a catalysing event, short-circuiting the process.
So, is it feasible to argue that actually, humanity represents on of the potentially older intelligent complex species that I agree must undoubtedly exist within the Universe?
And as O_G rightly points out, we are very reliant on quite a wide range of fairly specific cosmological and planetary requirements in order to have evolved at all - so just how likely is life like ours?
After all, the only evidence of life we have anywhere in the whole universe is found on just one planet...
I am still not entirely sure I fully understand the time scale over which planets could have formed earlier than our own, because that planetary formation - at least for a planet like ours, requires the presence of very large quantities of those heavy elements, such as Iron and the like, that are present within the Earth and indeed within its core.
So - The Earth forms 4.5 billion years ago, give or take a decade or so :) Universe formed around 14 billion years. Thats a difference of 10 billion years - but of that 10 billion years - how long did it take for other star systems to accrete out, form a sun, for planets to form? How much of that 10 billion years would be needed to give time for sufficient supernovae to have happened in order to create the vast quantities of, say, elemental iron needed to form earths core?
As for life itself - well we often talk about the length of time it took for life to become established on earth itself - estimates being what? around 1 billion years or so for the conditions to become right - and then we have the actual timeline of development of life from single celled organisms to complex creatures like humans. And within that timeline, we see Extinction Level Events - such as the meteor strike at Chixalub - to which the demise of the dinosaur is attributed. Such Events are often seen as having a retardation effect on the development of complex life like humanity - but they could be seen as a catalysing event, short-circuiting the process.
So, is it feasible to argue that actually, humanity represents on of the potentially older intelligent complex species that I agree must undoubtedly exist within the Universe?
And as O_G rightly points out, we are very reliant on quite a wide range of fairly specific cosmological and planetary requirements in order to have evolved at all - so just how likely is life like ours?
After all, the only evidence of life we have anywhere in the whole universe is found on just one planet...
Chaps, this from Stephen Hawking:
//The necessary planetary conditions for our form of life may therefore have existed from about four billion years after the Big Bang.//
… which is about 6 billion years before our solar system came into existence.
http://
//The necessary planetary conditions for our form of life may therefore have existed from about four billion years after the Big Bang.//
… which is about 6 billion years before our solar system came into existence.
http://
I thought you implied that humans were planted here:
" ‘Let us make man in our image’. Maybe they did, although not by supernatural means, but simply by populating the planet and procreating, even if that meant using a little genetic engineering – which would, of course, explain man’s as yet unexplained relatively sudden appearance."
It's not exactly planting, to be fair, but it does have the effect of elevating humanity from just another part of the chain of life on Earth to something that needed a kick from elsewhere. That does make humans "special", in some sense.
As to why is Earth so special, I'm satisfied that it was a premature question -- of course if you are looking for somewhere else to start life again, or similar, then you'd pick the most suitable nearby place, which just happened to be Earth, perhaps.
But why are these aliens not here any more? It seems somewhat odd that having survived long enough to develop the technology needed to up sticks and move to another planet that they would then have disappeared entirely within 2,000 years, say. Espeically if they did "create Man as servants" and wanted to be worshipped.
I thought Adam was the first man. Unless you are misinterpreting Genesis 1, but never mind about that. Any theory that aims to extract Scientific truths from a book written so long ago isn't particularly scientific. So what, beyond speculation, has this theory to go on?
The problem, too, with criticising my imagination is that it also warps the History of Science somewhat. There have been few times in the last few hundred years when Science -- or at least Physics -- has genuinely done an about-turn and completely disgarded all that came before it. Instead the story is one of refinement, to some extent. Sometimes drastic indeed -- the beginning of the twentieth century saw Classical Physics pushed aside as the theory of the small, and Galilean Relativity as the full description of the Universe -- but even then, the older theories retained some validity and are not "wrong".
So, now, we have a world of Science where for a century it has been seen that travel for a body at or near the speed of light and beyond is effectively impossible; that is unlikely to change, and imagining that it will is to pretend that the reasons we got to that conclusion don't matter.
I cannot imagine interstellar travel being feasible for some time yet -- too much would have to be wrong with what we have at the moment, or alternatively some entirely new method of propulsion needs to be discovered. The challenges, anyway, are not just technological.
Supposing, anyway, that they can be overcome, and were at some point. We still haven't really left the realm of speculation. Beyond some evidence in holy books that is open to much interpretations, is there anything more concrete on which this theory is based? Again, I am referring to directed panspermia rather than "natural" panspermia.
" ‘Let us make man in our image’. Maybe they did, although not by supernatural means, but simply by populating the planet and procreating, even if that meant using a little genetic engineering – which would, of course, explain man’s as yet unexplained relatively sudden appearance."
It's not exactly planting, to be fair, but it does have the effect of elevating humanity from just another part of the chain of life on Earth to something that needed a kick from elsewhere. That does make humans "special", in some sense.
As to why is Earth so special, I'm satisfied that it was a premature question -- of course if you are looking for somewhere else to start life again, or similar, then you'd pick the most suitable nearby place, which just happened to be Earth, perhaps.
But why are these aliens not here any more? It seems somewhat odd that having survived long enough to develop the technology needed to up sticks and move to another planet that they would then have disappeared entirely within 2,000 years, say. Espeically if they did "create Man as servants" and wanted to be worshipped.
I thought Adam was the first man. Unless you are misinterpreting Genesis 1, but never mind about that. Any theory that aims to extract Scientific truths from a book written so long ago isn't particularly scientific. So what, beyond speculation, has this theory to go on?
The problem, too, with criticising my imagination is that it also warps the History of Science somewhat. There have been few times in the last few hundred years when Science -- or at least Physics -- has genuinely done an about-turn and completely disgarded all that came before it. Instead the story is one of refinement, to some extent. Sometimes drastic indeed -- the beginning of the twentieth century saw Classical Physics pushed aside as the theory of the small, and Galilean Relativity as the full description of the Universe -- but even then, the older theories retained some validity and are not "wrong".
So, now, we have a world of Science where for a century it has been seen that travel for a body at or near the speed of light and beyond is effectively impossible; that is unlikely to change, and imagining that it will is to pretend that the reasons we got to that conclusion don't matter.
I cannot imagine interstellar travel being feasible for some time yet -- too much would have to be wrong with what we have at the moment, or alternatively some entirely new method of propulsion needs to be discovered. The challenges, anyway, are not just technological.
Supposing, anyway, that they can be overcome, and were at some point. We still haven't really left the realm of speculation. Beyond some evidence in holy books that is open to much interpretations, is there anything more concrete on which this theory is based? Again, I am referring to directed panspermia rather than "natural" panspermia.
Jim, //But why are these aliens not here any more?//
Who knows? Would we necessarily stick around on a planet we’d gone to mine, for example? Or perhaps we’re their descendants, and have lost the technology in the mists of time. It has been known. Think of some of the earth’s peoples who were far smarter in the past than they are now.
//Espeically if they did "create Man as servants" and wanted to be worshipped.//
Perhaps they didn’t want to be worshipped as such – just obeyed.
//I thought Adam was the first man. Unless you are misinterpreting Genesis 1,//
I’m not misinterpreting Genesis – but you are. Forget everything you’ve been taught and read it again.
//Any theory that aims to extract Scientific truths from a book written so long ago isn't particularly scientific.//
No, it isn’t – and I haven’t claimed it to be. Having said that, why does it have to be scientific? Learning from history works for me.
//So what, beyond speculation, has this theory to go on?//
I’ve told you. Ancient structures, writings, artwork, and legends – but having read the rest of your post it’s clear that you have no intention of giving it serious consideration because it doesn’t fit the status quo. The same old story. You are determined that our present view of the possibility inter-stellar space travel is “unlikely to change”, therefore, the theory doesn’t warrant further examination because it’s impossible. I really thought you were genuinely interested, but you’re not, so it’s a rather disappointing outcome. Thanks for the chat anyway.
LG, you're welcome. I like him!
Who knows? Would we necessarily stick around on a planet we’d gone to mine, for example? Or perhaps we’re their descendants, and have lost the technology in the mists of time. It has been known. Think of some of the earth’s peoples who were far smarter in the past than they are now.
//Espeically if they did "create Man as servants" and wanted to be worshipped.//
Perhaps they didn’t want to be worshipped as such – just obeyed.
//I thought Adam was the first man. Unless you are misinterpreting Genesis 1,//
I’m not misinterpreting Genesis – but you are. Forget everything you’ve been taught and read it again.
//Any theory that aims to extract Scientific truths from a book written so long ago isn't particularly scientific.//
No, it isn’t – and I haven’t claimed it to be. Having said that, why does it have to be scientific? Learning from history works for me.
//So what, beyond speculation, has this theory to go on?//
I’ve told you. Ancient structures, writings, artwork, and legends – but having read the rest of your post it’s clear that you have no intention of giving it serious consideration because it doesn’t fit the status quo. The same old story. You are determined that our present view of the possibility inter-stellar space travel is “unlikely to change”, therefore, the theory doesn’t warrant further examination because it’s impossible. I really thought you were genuinely interested, but you’re not, so it’s a rather disappointing outcome. Thanks for the chat anyway.
LG, you're welcome. I like him!
I'm well aware of the "two creation myths" aspect of Genesis, and expect that's what you mean. Either way, Adam is almost certainly meant to be the first man. The fact that Chapter one comes before Chapter 2 doesn't mean that they are in chronological order.
I think a theory that is proposing origins like that has to be Scientific. I think you're doing me somewhat of a disservice. I'm sceptical because I don't see that the evidence is anything more than a possible interpretation of history -- not necessarily more or less reliable than any other, I woldn't be able to say that, but an interpretation nonetheless. There are parts of it which are convenient as any other religion, in that essentially the founding culture seems to have "vanished" recently, without any concrete traces (albeit possible cultural ones).
I'm not sure why Scientific evidence shouldn't come into it at all. Allowing for the fact that Scientific laws are the best model of truth we have, then all origin theories should be measured against it. I say, on present theory there is little reason to believe that this is possible -- at least, not with the directing aliens actually coming with their "life seed". That may change in future, but again it seems unlikely.
It is, at least, rational scepticism, which is hardly a bad thing to have. With practice you can read anything you want into cultural evidence (hence the "Da Vinci Code" rubbish) -- that is a lot harder to do with experimental evidence.
I think a theory that is proposing origins like that has to be Scientific. I think you're doing me somewhat of a disservice. I'm sceptical because I don't see that the evidence is anything more than a possible interpretation of history -- not necessarily more or less reliable than any other, I woldn't be able to say that, but an interpretation nonetheless. There are parts of it which are convenient as any other religion, in that essentially the founding culture seems to have "vanished" recently, without any concrete traces (albeit possible cultural ones).
I'm not sure why Scientific evidence shouldn't come into it at all. Allowing for the fact that Scientific laws are the best model of truth we have, then all origin theories should be measured against it. I say, on present theory there is little reason to believe that this is possible -- at least, not with the directing aliens actually coming with their "life seed". That may change in future, but again it seems unlikely.
It is, at least, rational scepticism, which is hardly a bad thing to have. With practice you can read anything you want into cultural evidence (hence the "Da Vinci Code" rubbish) -- that is a lot harder to do with experimental evidence.
This is a very interesting post, (hope you don't mind the mad section joining you.) I have long held the opinion that our planet was seeded way way back,but what if it was done when early man existed & experimented to alter the gene pool to create more advanced creatures (us). I notice that some places of worship throughout the world look remarkably like rockets & space vehicles ( some even having '' booster rockets'' at 4 corners) these being of course the '' houses of the Gods'' who were visiting & have been replicated since.
(I must stop now a van has just drawn up outside containing men in white coats)
WR.
(I must stop now a van has just drawn up outside containing men in white coats)
WR.
Alternatively, if you are meaning where did the women who were Cain and Enoch's etc., wives - the Bible does not say where they came from, but "there was no one to work the ground" (Gen. 2:5) before "God formed a man from the dust of the ground and breathed into his nostrils the breath of life, and the man became a living being." (Gen 2:7).
I think it's safe to assume that the intention was to clarify that Adam was the first man; other woman then being his daughters, not mentioned. At any rate, it would only be speculation to suggest that the Bible implies other people existing beside, and before, Adam and Eve.
I think it's safe to assume that the intention was to clarify that Adam was the first man; other woman then being his daughters, not mentioned. At any rate, it would only be speculation to suggest that the Bible implies other people existing beside, and before, Adam and Eve.
Most of the Von Daaniken-esque 'evidence' is just as easily interpreted in other ways and there isn't any hard evidence that suggest that any life form with an intelligence and/or technical achievement similar to our own, native or alien,has ever existed on earth. The only contenders were possibly the bipedal dinosaurs that had spare 'hands' and room in their skulls for a large brain, but so far no evidence.
another supernova link;
http://
http://
"I really thought you were genuinely interested, but you’re not, so it’s a rather disappointing outcome."
Out of interest, does "being interested" meaning agreeing with you? I've read your replies, hopefully as carefully as I think I have, and wrote detailed and long responses to them. So far, that to me is interest. That I then disagree with the scheme doesn't mean I don't take it seriously -- far from it; that I've bothered to spend so much time debating it shows quite the reverse. Not all engagement should mean acceptance.
You also have to allow for the fact that I know my Science quite well, so that if someone suggests something that appears to me not to fit into that scheme then you shouldn't be surprised if I'm sceptical.
I don't know enough about your cultural evidence one way or the other but it seems on the surface that it's another attempt to explain where religion comes from. One that has to overcome severe practical difficulties, without just dismissing them out of hand -- that's what religious arguments tend to do: "Oh God can do anything" -- but is otherwise not impossible given the time spans involved.
Where ultimately the theory falls down for me is that it cannot really be proven one way or the other. That means that while it is interesting, it will surely only ever be speculative. Is that such a bad thing to note?
Out of interest, does "being interested" meaning agreeing with you? I've read your replies, hopefully as carefully as I think I have, and wrote detailed and long responses to them. So far, that to me is interest. That I then disagree with the scheme doesn't mean I don't take it seriously -- far from it; that I've bothered to spend so much time debating it shows quite the reverse. Not all engagement should mean acceptance.
You also have to allow for the fact that I know my Science quite well, so that if someone suggests something that appears to me not to fit into that scheme then you shouldn't be surprised if I'm sceptical.
I don't know enough about your cultural evidence one way or the other but it seems on the surface that it's another attempt to explain where religion comes from. One that has to overcome severe practical difficulties, without just dismissing them out of hand -- that's what religious arguments tend to do: "Oh God can do anything" -- but is otherwise not impossible given the time spans involved.
Where ultimately the theory falls down for me is that it cannot really be proven one way or the other. That means that while it is interesting, it will surely only ever be speculative. Is that such a bad thing to note?
I don't want to dwell too much on the Bibical part of this discussion, but:
http://
http://
Opinion is anyway divided, though even the second source ends "pre-Adamic society can indeed fit into the Biblical scheme" which is not definitive. Better analysis is out there... but why take the Bible so seriously anyway? This was meant to be a Science question, not an arts one.
http://
http://
Opinion is anyway divided, though even the second source ends "pre-Adamic society can indeed fit into the Biblical scheme" which is not definitive. Better analysis is out there... but why take the Bible so seriously anyway? This was meant to be a Science question, not an arts one.
Jim. //I'm well aware of the "two creation myths" aspect of Genesis, and expect that's what you mean.//
No, that is not what I mean.
//Either way, Adam is almost certainly meant to be the first man. //
According to what you’ve been taught.
I’m not doing you a disservice. You speak of rational scepticism, but *rational* scepticism comes from examining the subject matter thoroughly in order to make an informed decision - which is something you haven’t taken the trouble to do before making your mind up.
Incidentally, the Bible does tell us where Cain’s wife came from – the Land of Nod – so speculation regarding the earth being rather more populated at the time than we’re led to believe isn’t necessary. The answer is there. It was.
//Out of interest, does "being interested" meaning agreeing with you?//
No, it doesn’t, but since I’m an astute kind of girl who’s been studying this subject for years, I tend to recognise genuine interest – or otherwise.
//That means that while it is interesting, it will surely only ever be speculative.//
Will it? Are you sure?
Jom, //there isn't any hard evidence that suggest that any life form with an intelligence and/or technical achievement similar to our own, native or alien,has ever existed on earth.//
Not ‘hard’ evidence perhaps – but there’s plenty to give food for thought. Problem is most people think they know the answers already, so they don’t even bother to look before dismissing it, which I find very sad.
No, that is not what I mean.
//Either way, Adam is almost certainly meant to be the first man. //
According to what you’ve been taught.
I’m not doing you a disservice. You speak of rational scepticism, but *rational* scepticism comes from examining the subject matter thoroughly in order to make an informed decision - which is something you haven’t taken the trouble to do before making your mind up.
Incidentally, the Bible does tell us where Cain’s wife came from – the Land of Nod – so speculation regarding the earth being rather more populated at the time than we’re led to believe isn’t necessary. The answer is there. It was.
//Out of interest, does "being interested" meaning agreeing with you?//
No, it doesn’t, but since I’m an astute kind of girl who’s been studying this subject for years, I tend to recognise genuine interest – or otherwise.
//That means that while it is interesting, it will surely only ever be speculative.//
Will it? Are you sure?
Jom, //there isn't any hard evidence that suggest that any life form with an intelligence and/or technical achievement similar to our own, native or alien,has ever existed on earth.//
Not ‘hard’ evidence perhaps – but there’s plenty to give food for thought. Problem is most people think they know the answers already, so they don’t even bother to look before dismissing it, which I find very sad.
Jim, You are surely having a ‘larf’ with those links!!! Good grief! That says it all!!
There’s little point in continuing this with you – belief in the supernatural is far more plausible. ;o)
Anyway, I’ll be off now and leave you and the others to it. You did say on the other thread that Francis Crick supported this theory, which was what grabbed my interest initially, so I didn’t realise I wasn’t supposed to be discussing it. My apologies.
Sorry, Ron. Perhaps we can continue in R&S sometime.
There’s little point in continuing this with you – belief in the supernatural is far more plausible. ;o)
Anyway, I’ll be off now and leave you and the others to it. You did say on the other thread that Francis Crick supported this theory, which was what grabbed my interest initially, so I didn’t realise I wasn’t supposed to be discussing it. My apologies.
Sorry, Ron. Perhaps we can continue in R&S sometime.
Naomi, I can see from your posts that you are predisposed to the idea of some earlier intelligence whether native or alien but as I said earlier there is no evidence to support these ideas. Most of the 'evidence' is just speculation. What may to us look like a rocket in a primitive drawing probably was intended to represent something entirely different. Other cultures see things differently, kalahari bushmen find the concept of straight lines difficult and don't draw them. I have read the Von Daaniken books but their 'evidence' was hardly compelling. Following his reasoning Earth was visited by several kinds of aliens. To be practical, why is there no more 'evidence' than a few rock carvings or lines in the desert (long since explained by archaelogist) No major technological changes appeared around the time of these 'visits'. If gene pools were manipulated it was done too subtley to be detected. We could speculate endlessly about what could or might have happened but unless there is some hard evidence it is ultimately pointless.
Food for thought, perhaps. But, again,no hard evidence. Just speculation. Until that changes, and I don't expect it to in my lifetime, it's just speculation.
Another point, which is worth considering. At what time were these visitors supposed to have visited?
1. If 6,000 years ago, say, at the dawn of Abrahamic religions, then that's a bit late for them to have had any impact on the biological development of man, at least, which is what I was ultimately asking about.
2. If 6 million years ago, which is around about the time of the earliest supposed human ancestors, then that seems far too early, instead, to influence the cultural development of man.
In either case, on the surface neither theory is particularly appealing. It then comes down to well, is it even worth my while exploring the theory any deeper? To convince me of that you would need more than just some vauge reference to artistic and cultural considerations.
You spend an awful lot of time, it has to be said, in the R&S board rubbishing religions, and oddly, my attempts to take a middle ground on those too. Here I am instead, against one of your own ideas because it doesn't convince me, and suddenly I am guilty of being closed-minded?
I've tried to explain why I don't particularly like this theory, and I hope I've been fair. Earlier I made a point about "why this planet?" which you countered pretty well, and I accepted as much, so it's not like I've been ignoring you. No, you are doing me a disservice and being very patronising.
Another point, which is worth considering. At what time were these visitors supposed to have visited?
1. If 6,000 years ago, say, at the dawn of Abrahamic religions, then that's a bit late for them to have had any impact on the biological development of man, at least, which is what I was ultimately asking about.
2. If 6 million years ago, which is around about the time of the earliest supposed human ancestors, then that seems far too early, instead, to influence the cultural development of man.
In either case, on the surface neither theory is particularly appealing. It then comes down to well, is it even worth my while exploring the theory any deeper? To convince me of that you would need more than just some vauge reference to artistic and cultural considerations.
You spend an awful lot of time, it has to be said, in the R&S board rubbishing religions, and oddly, my attempts to take a middle ground on those too. Here I am instead, against one of your own ideas because it doesn't convince me, and suddenly I am guilty of being closed-minded?
I've tried to explain why I don't particularly like this theory, and I hope I've been fair. Earlier I made a point about "why this planet?" which you countered pretty well, and I accepted as much, so it's not like I've been ignoring you. No, you are doing me a disservice and being very patronising.
Pan-spermia is pretty much impossible the way it's mostly thought of
There's an important distinction between life and complex life.
Life started on Earth pretty much as soon as the heavy bombardment stopped - as soon as it was possible about 4 Billion years ago
Complex life started only about a billion years ago - mitochondria invaded the cell and the resulting union made life forms bigger than amoeba possible.
Outside of bacteria and the like pretty much everything we think of a living comes from that symbiotic relationship.
So If life came from space it was simple - we know that because that's all there was for 3 billion years.
That symbiotic union was terrestrial - it happened here and it lit the touchpaper for the Cambrian explosion and everything that followed.
If life came from outer space it was simple slime - and remained like that for billions of years.
You could just feasibly explain life by panspermia but not complex life
We don't know how common life is but the fact that it started here so easily whether natively or transferred suggests it is very common.
We cannot say the same for complex life - it could easilly be that complex multi-cellular organisms are an extreme rarity, a very very exclusive club of which we a club by sheer chance.
It could be that the Galaxy is swarming with life and we are the only complex self-aware examples in it.
Unless we find another example we have no way of knowing
There's an important distinction between life and complex life.
Life started on Earth pretty much as soon as the heavy bombardment stopped - as soon as it was possible about 4 Billion years ago
Complex life started only about a billion years ago - mitochondria invaded the cell and the resulting union made life forms bigger than amoeba possible.
Outside of bacteria and the like pretty much everything we think of a living comes from that symbiotic relationship.
So If life came from space it was simple - we know that because that's all there was for 3 billion years.
That symbiotic union was terrestrial - it happened here and it lit the touchpaper for the Cambrian explosion and everything that followed.
If life came from outer space it was simple slime - and remained like that for billions of years.
You could just feasibly explain life by panspermia but not complex life
We don't know how common life is but the fact that it started here so easily whether natively or transferred suggests it is very common.
We cannot say the same for complex life - it could easilly be that complex multi-cellular organisms are an extreme rarity, a very very exclusive club of which we a club by sheer chance.
It could be that the Galaxy is swarming with life and we are the only complex self-aware examples in it.
Unless we find another example we have no way of knowing
Jim, this is what you said on the other thread.
//Nobel Laureates sometimes get over-respected and, therefore, can get away with such crackpot ideas as Francis Crick's theory that Earth was "seeded [by aliens] with life". It's difficult for most to criticise someone like him so overtly as he has perhaps earned a right to speak such rubbish and be listened to respectfully.//
//That our planet was [i]deliberately] seeded is just barmy.//
Therefore, before we began this discussion here, you considered the ideas to be ‘crackpot’ and ‘barmy’.
//I hope I've been fair.//
You haven’t - but silly me for not taking your earlier statements more seriously. I have, until now, enjoyed our conversations and apart from the ludicrous links you posted – which for a serious student of religious history fully deserve to be rubbished - I have never ‘rubbished’ your posts. In fact earlier today I defended you against someone else’s unwarranted rudeness – resulting in an apology to you - but it won’t happen again. I wouldn’t dream of patronising you. Additionally, I haven’t accused you of being closed-minded – simply disinterested – but in that I was also mistaken. In posting this thread, supposedly to elicit my opinions, which you claimed ‘intrigued’ you, you have been insincere. Not to worry – my lesson is learned.
//Nobel Laureates sometimes get over-respected and, therefore, can get away with such crackpot ideas as Francis Crick's theory that Earth was "seeded [by aliens] with life". It's difficult for most to criticise someone like him so overtly as he has perhaps earned a right to speak such rubbish and be listened to respectfully.//
//That our planet was [i]deliberately] seeded is just barmy.//
Therefore, before we began this discussion here, you considered the ideas to be ‘crackpot’ and ‘barmy’.
//I hope I've been fair.//
You haven’t - but silly me for not taking your earlier statements more seriously. I have, until now, enjoyed our conversations and apart from the ludicrous links you posted – which for a serious student of religious history fully deserve to be rubbished - I have never ‘rubbished’ your posts. In fact earlier today I defended you against someone else’s unwarranted rudeness – resulting in an apology to you - but it won’t happen again. I wouldn’t dream of patronising you. Additionally, I haven’t accused you of being closed-minded – simply disinterested – but in that I was also mistaken. In posting this thread, supposedly to elicit my opinions, which you claimed ‘intrigued’ you, you have been insincere. Not to worry – my lesson is learned.
Latest Posts
News11 mins ago
News14 mins ago
And Even More Good News From Labour.
News20 mins ago
Brexit Hit To Uk Trade Less Than...
News21 mins ago
Related Questions
Sorry, we can't find any related questions. Try using the search bar at the top of the page to search for some keywords, or choose a topic and submit your own question.