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Why hasn't ET made contact yet?

Jonathan Amos | 17:53 UK time, Monday, 25 January 2010

He's absolutely convinced. Frank Drake has been scouring the sky for 50 years, looking for signs of extraterrestrial intelligence.

He's heard nothing... but he's in no doubt they're out there.

Drake was a founder-member of Seti, the Search for Extraterrestrial Intelligence.

Frank Drake and his famous equation.jpgSince 1960, this activity has been pointing radio telescopes at the stars hoping to receive some indication - perhaps even a message - that an advanced alien lifeform exists elsewhere in our galaxy.

Many of us have been involved directly in this search by allowing Seti to use downtime on our PCs to crunch the radio data for any interesting signals.

Frank Drake himself has been in London this week to attend the Royal Society's discussion meeting - The Detection of Extraterrestrial Life and the Consequences for Science and Society.

The scientist is most famous for the equation that bears his name.

Drake's Equation is an attempt to express the potential number of intelligent civilizations that might exist in the Milky Way.

The number is dependent on several factors, such as the scale of star formation, the presence of planets around those stars that might harbour life capable of sophisticated communication, and the length of time over which any evolved species would be able to get in touch.

Remember, although we've existed as a species for at least 200,000 years, it's only in the last 100 years that we've developed the technology necessary to send messages into space.

Seti Allen antenna.jpgThere are a lot of assumptions in this game but when Drake plugs numbers he describes as conservative into his own equation, he comes out with a figure of 10,000 civilizations.

It sounds a lot until you consider there are at least 200 billion stars in the Milky Way.

So, here's one reason why we've not heard a dickybird out of ET yet: our searches so far have been puny compared with the scale of effort that would be required to do a thorough audit of the Milky Way.

The search field is simply enormous and the distances over which signals have to travel are colossal - tens of thousands of light-years potentially.

Talking with Drake today, he also raises another complicating factor:

"In searching for extraterrestrial life, we are both guided and hindered by our own experience. We have to use ourselves as a model for what a technological civilisation must be, and this gives us guidance for what technologies might be present in the Universe.
 
"At the same time, this limits us because we are well aware that all the technologies that might be invented have not been invented; and in using ourselves as a model, we may not be paying attention to alternatives, as yet undiscovered and as yet unappreciated by us."

In other words, we've been listening for extraterrestrials' radio signals but this may not be how they're trying to announce their presence.

It's one of the reasons why Seti, in the last few years, has also started to look for the optical flashes that might originate from powerful alien lasers systems.

Alien landscape.jpgDrake highlights another fascinating issue - and that is that we ourselves are becoming invisible to the extraterrestrials searching for us.

The signals emanating from Earth most likely to reach distant civilisations are our TV broadcasts. But the switchover from analogue to digital television means "our voice" is being diminished.

Part of this is down to the TV satellites which deliver targeted beams to the Earth's surface; and also to cable TV which runs direct to the home underground. Both don't "bleed" as much into space as the old high-power analogue TV transmitters; and the digital signal itself requires a good deal more sophistication to interpret it.

Drake says this may mean in future we have to establish a dedicated system of beacons to broadcast our presence.

"There are people who're saying we should be running a beacon - a simple message that we send to one star after another, pointing out that we exist.
 
"When you think about that, you quickly reach the conclusion that there should be two beacons - one that's easy to detect and has only the information on it that tells you what radio frequency you should tune to to get the other beacon with a great deal more information.
 
"Right now, we don't have to do this because we're sending all this information through our television, but when the Earth goes quiet it makes much more sense."

I'm fascinated by people's reactions to this search - whether it has any point, and what we'd do if we got a contact.

Would we be filled with fear or excitement? How should we initiate a dialogue, knowing a reply might not come back for hundreds of years because of the light-travel time between our two locations?

Or would shocked and scared earthlings immediately want to "hang up" as if to say "sorry, wrong number"?

Comments

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  • 1. At 9:17pm on 25 Jan 2010, Paulo wrote:

    Scientists assume that civilizations would comunicate by radio waves. This is a childish assumption.

    Very advanced aliens could certainly communicate with much radical ways of communicating, like telepathy or who knows other faster than light ways. 500 years ago no one would believe that stuff like mobile phones would be really possible!

    During psycoactive experiences and even spontaneous out of body experiences people frequently report encounters with alien like entities. This would probably be a good starting point for open-minded scientists. Science frequently limits itself by its own (wrong) assumptions.

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  • 2. At 10:09pm on 25 Jan 2010, David wrote:

    Personally I don't think we should be advertising that we are here....

    There might be something out there that would view us as a food source, much as we view cows and sheep as a food source......

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  • 3. At 10:19pm on 25 Jan 2010, lsi-92 wrote:

    All this about Drake, but not a mention of the Fermi Paradox?

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

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  • 4. At 10:28pm on 25 Jan 2010, tacrepus wrote:

    I agree that we should not be advertising our presence. If we made contact with an alien life force tomorrow, how are we going to make them take us seriously as a species when the major events in the world are war, death and the slow desruction of our own environment. I can just imagine our politicans trying to lie their way through explaining it to a more intelligent life form. And before anyone mentions it, yes, I am aware that virtually anything that can walk and chew gum at the same time would be considered to be a more advanced form of life than most politicians.

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  • 5. At 11:03pm on 25 Jan 2010, beastless wrote:

    Paulo, how do you expect scientists to look for telepathic or out-of-body experiences when these haven't been discovered yet? Talk about childish assumtions!

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  • 6. At 01:08am on 26 Jan 2010, LA wrote:

    This comment was removed because the moderators found it broke the House Rules.

  • 7. At 03:08am on 26 Jan 2010, leoetal2000 wrote:

    I have been running Seti on my computer for at least two years even though I don't have a clue what the signals that are displayed mean. However, through several of my "sources" (some would say questionable internet sites and books, I admit) it has been reported that Seti has in fact been communicating with alien civilizations for years now, just not with the advertised radio telescopes (perhaps with lasers or using light beams or any number of alternative methods not known to the general public.) ET has known about us for eons. And, more to the point, there is no way so primitive a civilization would be missed just as soon as we started sending out radio and TV signals and detonating atomic weapons in our atmosphere. It seems to me that very advanced Type 2 or 3 civilizations would be monitoring the entire galaxy constantly looking for the type of danger Planet Earth could and does represent. The great mystery to me is that so many people on earth do not have the ability or the vision to realize that in a universe almost 14 billion years old and in a galaxy and solar system 5 or 6 billion years old with tens of billions of stars just in the Milky Way galaxy alone, that the chance of there Not being all sorts of civilizations both younger and much, much older is (in my considered opinion) exactly zero. This is the only logical conclusion. Either that or we are all living in some sort of a delusion that does not really exist...there are those who seem to think that is the case. Until we have proof positive, it's all just speculation in the end. But "The Truth is Out There"!

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  • 8. At 04:21am on 26 Jan 2010, Superdeedooper wrote:


    I very much agree with post number 7. It seems impossible that we are alone when all things are considered. I have been fascinated by all things space related and particularly the SETI since I was a boy. The implications for mankind of either finding life in our own solar system or INTELLIGENT life elsewhere are enormous. It would change everything I feel. However, like others, I dont think we should be advertising our presence. I dont want to wake up some day and find a city sized hostile UFO over my house !

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  • 9. At 06:30am on 26 Jan 2010, chris walker wrote:

    This comment has been referred for further consideration. Explain

  • 10. At 06:53am on 26 Jan 2010, Achiri wrote:

    Why do we always assume extra terrestrials would be more intelligent than us? May be the reason "they" can't contact is because they can't figure out what the hell radio signals are!! And ET life may have evolved in a complete different way from our perception. The idea that Mathematics is a universal language is a farce.

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  • 11. At 07:07am on 26 Jan 2010, Manoj wrote:

    It is so frustrating hearing that space agencies intend to send a probe to jupiter or revisit the moon by 2020. Although this will be fascinating no doubt, the thought that we are unlikely to visit another solar system outside ours within our life time is really frustrating. We just dont have the technology or know how to travel these distances at the speed of light and most probably wont know this for quite a long time!

    Therefore it is essential we carry on with this programme of seeking signs or contacting 'aliens'. But i do agree that we must use other methods than primarily focusing on tv and radio signals. Just look at how reception on your tv or radio can easily be distorted or interupted by bad weather. and this is within the area of our tiny planet! imagine travelling a few light years.....

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  • 12. At 08:14am on 26 Jan 2010, Mike wrote:

    Perhaps in describing the dimming & obscuring of our signals due to the digital switchover, Drake has answered his own question of why we cannot detect ET radio broadcasts.

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  • 13. At 08:41am on 26 Jan 2010, Mental_Wanderer wrote:

    Our own radio signals cannot have reached more than about 80 or 90 light-years away. Since SETI has already surveyed the near-by candidates, it is unlikely that we have roused the curiosity of any sentient listeners within that relatively tiny sphere. The first really powerful signals we sent, however, will tell them our species is about to self-destruct. Think about it: images of Hitler are the first TV signals our planet ever broadcast, followed a few years later by scenes of war and the new-found atomic bomb. They will probably be utterly mystified by "I Love Lucy" and "Queen for a Day," and horrified at "The Camel Newsreel Theater" and "Meet The Press." If these reach a civilization that can travel through space at speeds that exceed the official speed limit, (the speed of light), they will likely swoop down on us with giant pest control ships to eradicate us before we escape to infest other worlds. On the flip-side, since the near-by stars do not seem to be sending any signals, the ones we eventually hear will represent broadcasts that were made thousands -- and perhaps millions -- of years ago. Unless they are very unlike us, they will have already destroyed themselves long before we finally receive their overtures.

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  • 14. At 08:44am on 26 Jan 2010, callisto wrote:

    As someone who works within the space industry, I am astounded at the delusions carried by the public. We (the scientific community) are clearly not doing a good job with explaining simple science and raising popular awareness above Star Trek status.
    Mankind MUST stake out our own back yard first. In doing so, we will learn to travel easier and develop hardware to travel further. But forget zooming around at light speed or transporter beams. Focus on the science.
    Chris Walker - don't confuse religion and science. You have your beliefs (that's fine), but when you learn to base belief on fact or scientific evidence rather than shallow supposition and reverse conspiracy, then true enlightenment will follow.
    If there is intelligent life out there - let it find us. The cat always gets the bird that sings loudest. In the meantime, get real people.

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  • 15. At 09:04am on 26 Jan 2010, dukeofearl wrote:

    Just reading "Quantum Evolution" by Johnjoe McFadden, which has an interesting take on this.

    To summarise, if we work back to when simple organic molecules had to grow to even a simple pre-cellular replicating form of life on Earth, then there are millions of times fewer carbon atoms in the known universe for it to have happened randomly - the old monkeys typing Shakespeare problem.

    That it did is somewhat obvious, so McFadden takes the view that at the quantum level, all the options were tried as a quantum superposition of the available carbon molecules. Using the multiverse quantum description, we are the universe where it worked - in trillions of other universes it did not.

    This then makes any other life in this universe impossible, because each form of life would only appear in its own version of the universe amongst the multiverses and would never be visible or contactable.

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  • 16. At 09:09am on 26 Jan 2010, The_Oncoming_Storm wrote:

    I certainly think life is quite widespread throughout space but intelligence is a different matter. The history of Planet Earth is full of events that either made the development of our civilisation more likely, such as the formation of the Moon from the Theia Impact Hypothesis which resulted in Earth having a stable rotation as a result of the Moon's presence, or mass extinction events that could have wiped out our ancestors, the Permian Event wiped out 95% of life had it been a bit more severe then our mammalian ancestors may well have perished also.

    Therefore I think intelligent life is a lot rarer than the Drake Equation suggests, if it exists then I believe it's in a remote part of the Milky Way, thousands of light years away from us and probably beyond any way of contact.

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  • 17. At 11:00am on 26 Jan 2010, Ed wrote:

    The earth has about 5 billion years, if life on another planet developed 10% faster than on earth it now may be 500 million years old. There are some questions, how long a civilisation (or better its scientific, technological and cultural knowledge) can survive? Is it ever possible for a civilisation to move to other stars (and of course this may increase its chance to survive)? Even at one thousandth of the speed of light it may take just 100 million year to cross the galaxy, and spread almost everywhere (even not far from our solar system, so we may be able to make a contact).

    By the way I think SETI is worth to be pursued, because when we don't know we must "measure". It is the only way science has advanced.

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  • 18. At 11:07am on 26 Jan 2010, chris walker wrote:

    This comment has been referred for further consideration. Explain

  • 19. At 11:14am on 26 Jan 2010, Steve Brayley wrote:

    Reading all comments posted on this there are alot of good/bad points. I believe the known universe is too big not house more than just us. Will we meet any of them in our life time very unlikely down to the fact that the major countries would rather spend billions on weapons development and in comparison peanuts in conquering space travel.

    If there are more advanced life forms out there who says they have to be carbon based oxygen breathers?? why not based on other key elements Hydrogen for instance. Also why would they want to contact a lesser lifeform? ok this is going to delve into trekky areas but the prime directive in star trek is not to interfere in life that has not evolved to a certain level. To me this would seem a fundemental rule. If some life form came here giving us some super reactor to allow us free energy that could also be harnesed as a weapon what would we do with it? answer that and you'll know why we've not been contacted seeing as even now war rages on this planet.

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  • 20. At 11:26am on 26 Jan 2010, Michael Lindman wrote:

    Even though we might find alien life on other plants and systems they won't nessecerlly be any more advanced then we are now, they may even be humanoids depending on the ecosystem and evolution of the planet they came from. Also communication with any other lifeforms would be almost impossible as I doute that any alien would be able to speak or understand the English language let alone the other languages on Earth.
    In conclusion we have no way of knowing how advanced aliens lifeforms would be and even if they did find information relayed from earth they may not know how to encode and retrive it let alone understand it.

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  • 21. At 11:26am on 26 Jan 2010, Gimlock wrote:

    Some of the nearest Exoplanets are 20 light years away so even using light such as powerful lasers would mean a very long and stilted conversation, so 40 years for something to say hello back to you. I think using radio waves it could be several hundreds of years for those early signals to find something and perhaps get a reply of some sort which our great great grand children would have to process.

    Our Galaxy alone is too vast, other civilizations would be no different to us in that propulsion beyond the speed of light is considerd impossible to achieve. Unless a way is found to manipulate Space and Time you can forget it, if Man is ever going to explore other star systems it will have to be generations living in vast starships or terraformed asteroids travelling space over thousands of years. Those people would no longer be Earthlings and for all we know there could be beings like this already out there who's home Planet ceased to exist a long time ago.

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  • 22. At 11:41am on 26 Jan 2010, Paul wrote:

    I think another consideration that should be taken into account is that if you where wandering along a new street and wanted to make friends with new neighbours, would you knock on the door of the house were the people always seem to be fighting and quarrelling. I don’t thing I would.

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  • 23. At 11:53am on 26 Jan 2010, Matthew King wrote:

    Without entering the debate as to whether it's possible that life could exists elsewhere in our universe, I would like to put forward the argument that wherever it does so, a tendency to increased intelligence is an inevitable consequence.

    Clause: this arguement is based on the assumption that primitive life would evolve elsewhere as it has done so on our planet - with the development of communities, an ability to transfer genetic material thereby leading to speciation and thus, eventually, the formation of complete ecosystems (which could even be argued as another consequence of life - niche filling).

    Logic: Any such system would be subject to Darwinian selection... in such a system, it is arguable that one of the most advantageous phenotypic traits, in addition to a high reproductive drive, is increased intelligence - only because it is able to substitute for a multitude of other deficiencies such as strength, camouflage / natural defences, unattractiveness (perhaps this explains humour ;)...

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  • 24. At 12:49pm on 26 Jan 2010, Graphis wrote:

    Evidence that there MUST be intelligent life out there resides in the simple fact that they HAVEN'T made themselves known to us. After all, looking at our planet, would you? Even assuming they could receive and understand our signals, they would have to be intelligent enough to know that we'd shoot them on sight first, and then debate whether we should have done afterwards.

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  • 25. At 1:11pm on 26 Jan 2010, Paul wrote:

    callisto...

    "when you learn to base belief on fact or scientific evidence rather than shallow supposition and reverse conspiracy, then true enlightenment will follow."

    What do you do when you realise that every supposed "fact" or piece of "scientific evidence" is all based on just as much assumption as religion? You can't irrefutably prove that anything outside of your own consciousness is real.

    Maybe aliens exist, maybe they don't, maybe they're already amongst us, maybe they're the ones that created us or our universe. Who knows, we can't prove any of it anyway.

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  • 26. At 1:42pm on 26 Jan 2010, KPB wrote:

    I can't even pick up digital TV on the Norfolk coast, so what hope is there that aliens are tuning in?

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  • 27. At 2:45pm on 26 Jan 2010, istuart12 wrote:

    Following on from the comment by JPSLotus70, you might want to read a very good book on this subject, "Rare Earth" by Peter Ward and Donald Brownlee. They suggest that life itself is quite common, in the form of bugs, but that intelligent life is probably very rare.

    Simple life can form quickly, but for intelligent life, you need a fairly stable planet, with just the right conditions for an extended period. Apart from a stabilising moon, for example you would also need plate tectonics, and just the right amount of water on the surface.

    We definitely do not live in a Star Trek galaxy: Its lonely out there, a point well made in Carl Sagan's "Contact".

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  • 28. At 3:39pm on 26 Jan 2010, Manoj wrote:

    I truely do not understand why we have different space programmes for different countries and why we have China, Russia and USA competing against each other about who will be the first to the moon, or to mars or where ever.

    The sooner we realise that we are all humans here, part of planet earth, the sooner we are going to make strides in exploring our galaxy and universe. If all countries had worked together since space exploration was first thought up we would probably have already had a man on mars by now. Instead we choose to compete against each other rather than pulling all our resources together and becoming more efficient.

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  • 29. At 4:13pm on 26 Jan 2010, The_Oncoming_Storm wrote:

    #28 Manoj. it's politics simple as!

    However that is a two edged sword as it's likely that without the Cold War and the need for the US and the USSR to try and demonstrate that it's system was superior no one would probably have set foot on the Moon by now!

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  • 30. At 4:34pm on 26 Jan 2010, InjunTrouble wrote:

    Actually the ETs have already made contact long ago with the US as well as other western governments. This contact has been kept hidden by these governments (mainly the US) for the purpose of its own capitalistic, imperialistic agenda. They are fearful that they will loose control of the political, economic world order if the truth about the ETs is known.

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  • 31. At 5:54pm on 26 Jan 2010, James wrote:

    Aliens are almost certain to have a similar mindset to us. The only way to accumulate the kind of knowledge needed to reach a 'high' state of civilisation is by passing on data to our children and we only do this because we care for our children. This is not the only successful strategy for ensuring the survival of our genes but it is the only one that allows us to look beyond life on earth and the same would apply to any other life form on other planets.

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  • 32. At 6:44pm on 26 Jan 2010, modernJan wrote:

    "3. At 10:19pm on 25 Jan 2010, lsi-92 wrote:
    All this about Drake, but not a mention of the Fermi Paradox?

    http://en.wikipedia.org/wiki/Fermi_paradox "

    1) There are a lot of gas clouds in our galaxy that block signals like radio and lasers.

    2) EM-signals (radio, lasers, microwaves, etc...) attenuate with distance, so they may be too faint for us to detect.

    3) The aliens could have switched to other forms of communication or gone "silent" long ago, so that their EM-signals already passed Earth before humans could receive these signals.

    4) If a handful of probes or ships ever visited Earth before written history, or in remote parts of he world with tribal societies all we would have to go on would be legends of "gods" from the skies (those are in fact plentiful), so long as they didn't influence large empires like the Roman Empire or current Western civilization we would never know about it, even if a probe crashed/landed very recently it might have gotten buried under the sands of the Sahara or the icecaps of Antarctica and even now they might be here without us even knowing about it (advanced stealth technology).

    5) Lastly there is the possibility that some people already know they were here (artifacts were found) but keep this information hidden from the general public.

    So there are plenty of ways to escape Fermi's paradox.

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  • 33. At 6:52pm on 26 Jan 2010, modernJan wrote:

    "Even though we might find alien life on other plants and systems they won't nessecerlly be any more advanced then we are now, they may even be humanoids depending on the ecosystem and evolution of the planet they came from. Also communication with any other lifeforms would be almost impossible as I doute that any alien would be able to speak or understand the English language let alone the other languages on Earth.
    In conclusion we have no way of knowing how advanced aliens lifeforms would be and even if they did find information relayed from earth they may not know how to encode and retrive it let alone understand it."

    There are certain patterns of signals that do not occur in nature, so even if aliens cannot decipher our language they will know it came from an intelligent source and could send a reply (for example returning the message with a slight, unnatural variation so that when we receive it we will know it came from an alien civilization).

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  • 34. At 7:50pm on 26 Jan 2010, Benefactor wrote:

    I think some posters assumptions that aliens wouldn't be interested in us or would want to wipe us out is certainly valid, although not because of the war, famine and environmental destruction but for the massive self-depreciating emo outlook of the Human race.

    "boooo we suck!" "why are we always warring?!" "I hate the human race!"

    Christ, what a bunch of whiners.

    Well, that and if they exist they are probably either cave men or some godlike alien equivalent of transhuman.

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  • 35. At 8:04pm on 26 Jan 2010, Darren Stephens wrote:

    @Mental_Wanderer: all true but only one half of the equation.

    For a signal to have reached us now, any other possible civilisation must either have started transmitting thousands of years ago to reach us now, or be close by. We can't make assumptions about the distribution of potential intelligent life.

    Perhaps the signals are on their way now, but have yet to reach us. Who knows, but it seems weird that we'd be all alone in a universe this size...

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  • 36. At 8:10pm on 26 Jan 2010, U14314645 wrote:

    One point everybody seems to miss is this. It isn't altogether safe to make assumptions about life in general from just one example - the Earth - but it's almost certainly the case that if life exists elsewhere, it's at least roughly similar to what we know, for the simple reason that carbon is overwhelmingly better suited to form the complex molecules needed for life to exist in any form than any other element; and for this to take place on a grand scale, conditions can't be too dissimilar to those on Earth, especially temperature. Liquid water is also so very useful to carbon-based life-forms that we can pretty much take its presence for granted on any world bearing life, intelligent or not. Obviously in a Universe this size there may be a few exotics, but the vast majority of living things have to be carbon-based like us (silicon has some potential to form complex molecules, but only at very low temperatures, therefore those silicon-based critters beloved of bad sci-fi will be forced to live in extreme slow motion, meaning that they'll evolve at the same rate).

    So as planets harbouring intelligent life go, this one is probably a pretty fair example. But how smart do animals ever get? Clearly, having a brain of some sort as opposed to none at all is helpful if you don't want to randomly bumble around trying to eat rocks (or indeed mate with them), but equally clearly, in order to be a successful animal, you don't have to be quite as smart as us. Dolphins, apes, and some birds (parrots are smarter than you think!) are very bright indeed, but they're the exceptions. Dinosaurs lasted much longer than us, and almost certainly died out due to a cosmic event that evolution couldn't possibly have prepared them for, but they never bothered to get any smarter than wolves. Why not? Because that's as clever as you need to be to be an enormously successful animal. And that's what evolution is all about. Humanity is, as far as we can tell, a freakishly over-bright mutant species descended from one woman (I'm not sure how they know she was a woman, but feminists everywhere no doubt take great pride in this fact) who just happened to grow such a big brain that our skull-size still causes problems when we give birth.

    So basically, unless you believe in some religious or quasi-mystical quantum hypothesis that states that the Universe actively wants intelligent life to exist (which it doesn't - it's just there, OK?), life may very well be quite common, but only a tiny proportion of biospheres will ever evolve a beastie capable of building a radio. And incidentally, radio is undoubtedly the way that ETs who are not able to somehow exceed the speed of light (trust me on this - if you can do that, your science is basically magic, and you can do anything whatsoever, up to and including being God) would attempt to contact other equally intelligent species. Lasers may be more efficient, but they're directional. Radio goes in all directions - which is why everybody within 74 light-years has now received pictures of Hitler opening the Munich Olympics - oops! Klaatu barada nikto!

    So... Religious considerations aside, they're almost certainly out there; but there aren't very many of them, and we'd be bloody lucky (or possibly unlucky) to have another another intelligent species within hand-shaking distance. Alien probes haven't gotten here for the simple reason that objects traveling at close to the speed of light experience major problems with radiation and space-dust impact (a consequence of the laws of physics - check it out if you don't believe me) and a sparsely-populated galaxy this size would take a while to explore in this fashion, no matter how determined you were to do it. The only sensible way to make contact, assuming that you want to, and assuming that you aren't gifted with magical pretend space-hippy Star Trek powers of telepathy that exist because I say so, is radio. So let's listen up! It doesn't matter who they are or how far away they are - the likelihood of physical contact in the foreseeable future is basically zero, and that includes city-sized flying saucers destroying your neighbourhood for no reason at all (hey, if they were going to do that, would they bother to ask?).

    But wouldn't it be something if we got a reply?

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  • 37. At 9:34pm on 26 Jan 2010, Lem wrote:

    We are just now finding out that some animals on this planet are more intelligent than we thought. How are we going to know who's out there until we know more about what intelligence is? Not only that, but we can't even communicate with elephants yet, and how long have we lived on the same planet? The point is, we are just now (in the last few years) been willing to admit that other creatures can and do communicate, make tools and play games. Even if ET can hear us, they may not recognize our attempts. ET may not be interested in the existence of other intelligence in the universe. ET, if it exists, will be so different, that we won’t be able to tell it from a rock.

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  • 38. At 06:21am on 27 Jan 2010, Michael wrote:

    We must get in touch with aliens! maybe with their gigantic intellects they'll be able to tell us if Brad with get back with Jen!

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  • 39. At 10:22am on 27 Jan 2010, Andy Little UKIP wrote:

    In sending analogue or digital TV, laser modulation, or wide band light spectrum emissions, only one thing is true. We are here we can be seen.
    Now as we know they visit us, not all stories are cranks, a second fact is also true. If they have the technology and ability for space travel they must also have the abilty to decode out TV/Radio/Light signals and they see us, War mongering, Greedy, virus like, Carniverous, untrust worthy humans. If you were them would you WANT to make first contact?
    They might be killed by panicky public, eaten by politicians, or stuffed into jars in a lab... and they could be alliens no bigger than an ant!

    Human kind is not ready for first contact, to many governments hiding things, to much horror and suffering. Peace and Truth is not our planets way is it...

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  • 40. At 12:19pm on 27 Jan 2010, Benefactor wrote:

    Even if hypothetical aliens are all 'peace and love' that still doesn't mean they would hate us. They must have agressive and competitive instincts to get to the top of the food chain and out into space, most likely they would look at us and think "Oh, reminds me of when we where young"

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  • 41. At 12:38pm on 27 Jan 2010, Steve B wrote:

    A point not considered so far is that we may simply be among the first technological civilizations to exist in this Universe.

    Our universe is about 13.7 billion years old. At 4.5 billion years old, the Earth is about a third as old as the Universe it is in.

    In order for rocky planets like Earth to form, the hydrogen and helium formed in the Big Bang has to be fused into elements with larger nuclei and hence higher atomic numbers, notably carbon, oxygen, nitrogen, silicon (for rocks) and indeed iron (for a core with a magnetic field to protect from cosmic rays etc).

    For this to happen, stars brighter and more massive than our Sun have to be born, grow old, and die in supernova explosions, progressively enriching the interstellar dust - from which new stars and planetary systems form - in heavier elements. It's true that smaller, Sun-size, stars spew out into space elements with lower atomic numbers than iron such as carbon and oxygen when in their old, red giant, phase, but it takes 5 billion years for a sunlike star to do this, and even longer for the much more common orange and red dwarf stars to do so (the universe isn't old enough yet for even the first stars much smaller than the Sun, which 90% are, to reach that stage). But any elements with atomic numbers equal to or more than that of iron only get into the pot to make new stars and planets if they are made in a star massive enough to blow up. It's a thought to ponder that to make the iron that makes our blood red, and the gold in a wedding ring, a star died before our world was born...

    Studies of stars suggest that most stars much older than our sun have far lower proprtions of elements heavier than helium (lower "metallicity" in astronomer-speak) than the Sun and younger stars. Which suggests that our Solar System is one of the older planetary systems with rocky Earthlike planets to have formed in the Universe. The first generations of stars bigger than our Sun had to be born, grow old and die to make us even possible.

    Add to that the fact that it took half the age of the Earth to evolve anything more complex than a prokaryotic "germ" type cell, and three-quarters of the Earth's age to evolve creatures with more than one cell, and indeed almost 90% of the Earth's age to date to get beyond worms and jellyfish to the sort of creatures that you'd find in a rock pool. At each stage - as has been pointed out by other posters - we don't know how likely the next stage was to arise. So it looks like it takes a long time for suitable planets to grow complex life. Indeed the Earth was 94% of its present age before life had spread to colonise most suitable land, sea and air environments (about 270 million years ago). Finally, and after at least 2 mass extinctions that devastated life on Earth, modern humans only arose about 50,000 years ago (when the Earth was about 99.999% of its present age), recorded history goes back only 5000 years (the last one-millionth of the Earth's existence) and we've only had the technology to receive or transmit any sort of signal over interstellar distances for about 50 years. And we don't know how long we'll survive at that or higher level of technology, or at all...

    My guess is that advanced communicating civilizations, even if potentially they are a likely thing for Earthlike planets to grow after a few billion years, have only started sprouting in our Universe for maybe the latest 5-10% of its lifetime. We may well not be the first, but so far we are one of the first, the others are a very long way away, and signals from them will not reach us for a LONG time.

    When the Universe is twice its present age, I'd expect intelligent life in it to be obvious to other intelligent life, and Fermi's Paradox to be a thing of the past. We came too soon to the party, before the other guests turned up...

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  • 42. At 2:30pm on 27 Jan 2010, Alex wrote:

    Aliens probably are already here! Most of the comments here do not address the UFO factor. This is something which cannot be ignored. I believe that some sort of intelligence which is not from this world has been visiting us for quite some time. I understand that current science finds it hard to accept that space travel from one star to another is impossible for us with our current technology. However the history of Unidentified Flying Objects goes back to the days of World War II if not farther back. During the war these objects (Foo Fighters) were seen by both Axis and Allied pilots. They performed maneuvers no aircraft had in those days. After the war incidents such as the Mt Rainer sightings in 1947 gave way to the term flying saucers because the pilot (Kenneth Arnold) who saw them described them like saucers skipping through the air. The Roswell incident came next. There the Army Air Force first came out and said they recovered a disk. Later they withdrew the statement and reduced the find to a weather balloon. Somewhere in this confusion the truth became buried. However the sightings continued over the decades. Some of the more famous and unexplained ones are for example the 1986 Japanese Air Lines cargo freighter incident over Alaska. The pilot reported a gigantic UFO following his 747. It was confirmed by FAA ground Radar. The story later disappeared and became forgotten. Then you had the Belgium 1989 triangle sightings. The Belgium Air Force's F-16's couldn't keep up with them but did manage radar locks. The triangles were also seen by police and civilians on the ground. In 1997 the Phoenix incident was seen by thousands of people when a large V shaped craft flew silently overhead. People including then Governor Symington saw this craft and said it was huge. The biggest craft to fly made by humans was the German Zeppelin Hindenberg. She was about 800 ft long. This V shaped craft was much bigger! In fall 2006 the Chicago O'Hare airport had a UFO incident. The object was over a runway for a number of minutes and seen by ground crew, pilots, mechanics, passengers and even the control tower confirmed something over the runway. The witness who saw it said it was not weather related such as clouds or fog but some sort of craft. This UFO incident also was forgotten. The most recent incident is the Stephenville Texas sighting. Many witnesses described a large object that made no sound flying overhead. The airforce claims it was their F-16's perfoming training exercises...What to believe! While I enjoyed reading the BBC news article about possible life elsewhere on maybe planet Mars or the moon Enceladus or some planet orbiting a distant star. I feel that somewhere science is missing the boat here. There just may be alien life here on Earth and it's much larger than microbes. UFO's need to be seriously studied. The sightings have gone on for over 70 or more years.I don't think they are secret aircraft since from the earliest sightings they have superior flight capabilities. The British, French and some other countries are starting to come out with their own UFO incidents and some have no rational explanation other than they are some sort of intelligent controlled vehicle. When former astronaunts, pilots, retired military officials and civilians come forward to say they have seen things which exhibit technology which we don't have it's time to rethink the whole UFO phenomneon. While a many of the sightings are natural phenomneon or hoaxes enough remain that can't be explained away. I think the SETI termed ( Wow) factor in which they described a peaked radio signal is already in our own backyard. The UFO incidents still continue. We just need to investigate what it is!

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  • 43. At 3:01pm on 27 Jan 2010, Stephen Ashworth wrote:

    Steve B, I agree with you. The Universe may seem shockingly old to us, but on its own terms it's still only young.

    I'd like to point out that the radio search for signals from other stars is very unlikely to turn up anything. The reason is that we are clearly unable to detect even a twin of our own civilisation in the Alpha Centauri system (the nearest extrasolar system with a sunlike star), if we look for radio spillage alone. But I gather that we could exchange signals with such a civilisation if we both knew of each other's existence. In other words, the SETI project depends upon signals being deliberately sent to our planetary system by the aliens.

    Why would they do this? There is no economic sense in their signalling vast numbers of stars for millions of years at a time, hoping that a radio-enabled civilisation may meanwhile evolve in one of those target systems. They will be pumping out radio energy for a purely hypothetical return which may never come. Far more likely they will send interstellar robot probes to nearby planetary systems. The crossing times are only on the order of a few centuries, and the payoff will be precise close-up observations of the planets at the target star, regardless of whether or not high-tech life is present.

    Therefore the aliens will only signal us if they already have a robotic probe in our system, in which case they will know of our existence through that probe's observations. Presumably they will get in touch, if they decided to do so, through the probe.

    If we do not detect an alien probe in our planetary system, then any aliens that exist out there will not know of our existence and will have no reason to signal us.

    I think we're more likely to detect alien civilisations through the appearance of Dyson spheres around other stars. But, as I said, the universe is probably still too young for this to have happened yet.

    Stephen
    Oxford, UK

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  • 44. At 5:39pm on 27 Jan 2010, andy765gtr wrote:

    lets hope there is some extra terrestrial intelligence, cos, what with half of humans being creationists and the other half being AGW deniers, not to mention all the eternal economic growth/population growth believers, there is bugger all intelligence here on earth!

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  • 45. At 7:28pm on 27 Jan 2010, Rico wrote:

    In response to Paulo's comment, if scientists didn't make some assumptions, science wouldn't get anywhere. And scientists do not assume that extra terrestial signals would be transmitted using the same technology as us, its just that this is all they have to go on because this is all we know of (it actually says this in the article). And you say that scientists' assumptions are wrong, but how can you know whether or not they are wrong. You yourself are making an assumption here, one which is based on no logic as far as I can tell.

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  • 46. At 10:31pm on 27 Jan 2010, Giles wrote:

    Lots of interesting ideas here. There is one thought that seems to elude this forum, though. How does life appear in the first place?
    Did a meteorite or comet plant the ancient seeds of life on our planet? Some seem to think that it was ET himself who put us here (not the most outrageous theory, considering how an egg needs to be fertilized in order to spring to life). What about string theory? Or the elusive multiverse? The most common assumption (besides creation theory) seems to be the belief that life can just materialize under the right conditions, presumably from a well-placed lightning bolt in a cesspool of 'primordial soup', thus breathing the spark of life into one lucky little prokaryote that would embark, albeit unwittingly, on a harrowing quest to evolve into an intelligent life form (Note to self: potential Disney pitch).
    Even in this naive, rosy context, it's easy to look past the elephant in the room: life, even in its simplest form, is the most baffling, weirdest, awe-inspiring, irrational, unexplainable, and (as far as we can tell) the rarest phenomenon in the universe.
    This is the source of my doubts about E.T. What Drake's Equation doesn't seem to acknowledge is the extensive, seemingly impossible checklist of prerequisites for a life-sustaining planet. Let's take a look at ourselves, shall we... Our planet is conveniently situated in the 'green zone' where we aren't too close to or too far from the sun, keeping us nice and cozy. A molten iron core (complete with fully functional plate tectonics!) is quite useful as well, shielding us from pesky cosmic rays and keeping our planet from freezing up from the inside-out, thus becoming a dead planet (think Mars). The Moon is perfectly situated to promote life, and the same goes for our super-massive big brother (Jupiter) who's kind enough to absorb all of the big cosmic collisions that would happily sterilize our planet in an unceremonious bang. Add to that the impeccable timing of our existence as a species (thank God we weren't around at the end of the Permean) which has allowed us to grow big juicy brains that are capable of taking a step back and asking that highly pretentious question, "why?"
    Getting to the point - evolution isn't quick enough to out-flank chaos, and any given lifeform on any conceivable planet in any galaxy, foreign or domestic, is subject to a strict timeframe as far as developing the intelligence necessary to sever dependence from its respective mortal celestial bodies (yes, the sun and Earth will someday cease to exist) and become the transient, intergalactic masters of the universe that we imagine when we think of ET. The universe just doesn't allow that much time for biological development.
    Have you ever, when feeling especially introspective and philosophical, caught a fleeting glimpse of the strange and terrifying nature of our conscious existence on this inanimate rock? Thus begins religion, or some other such bumbling vanity used to justify our existence and make us feel safer and in control.
    There's only one fact I've acknowledged in the search for my own bumbling vanity: All religion aside, existence (life included) is an awesome miracle which we will never be able to fully comprehend. Like moderation, agnosticism in all things. No harm in trying, though. Go science!


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  • 47. At 09:47am on 28 Jan 2010, BSmith wrote:

    Have you heard of Dr. Claudio Maccone's Statistical Drake Equation? He uses statistical methods to produce a probability density function for extraterrestrial life, and has some interesting results!

    You can read more here: http://www.tauzero.aero/site/html/on_edge.html#ETI

    Since his work suggests that the nearest ET civilization is most likely to be about 2000 ly away, it's unsurprising that we haven't heard anything yet!

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  • 48. At 10:07am on 28 Jan 2010, shirley frost wrote:

    Its ridiculous to say that we have not heard from ET. Firstly, they are flying their amazing space craft in our air space on a daily basis to let us know they are there. ~Secondly, they are channelling information and advice telepathically through selected named channellers who can be freely accessed on the internet. Thirdly, certain races have been running this planet for thousands of years and have deliberately kept us darkness for their own convenience; one (negative)race in particular have been living here underground since 1953 by agreement with the US government and have secretly passed on certain technological innovations.
    Fourthly, we are all ETs cos we all came here from different parts of the universe to have a unique experience on planet earth. They desperately want to come here and be re-unite us back into the Galactic Family but they are stalled by the warlike demeanour which prevails here and that when they show up they are attacked by our military. Also because we are so backward and we are stuck in a 3rd dimensional conciousness whilst they are in 5th dimension and above.
    We are moving in their direction but slowly and if there are not massive changes very soon in our lifestyle and demeanour(and I mean months) we will forfeit the opportunity to transcend the third dimension and live in a virtul paradise. Nuff said I think. Actually a few years ago the Galactic Federation did actually manage to take over ITV for a few minutes and put out such a message. I witnessed it myself. The reason that we are moving upwards so slowly is because we have been duped into believing that what we experiencing is all there is and we are alone. Once we are able to drop those beliefs and create peace around the world we we will have visitors from beyond. This was the norm at an earlier stage in earth history.

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  • 49. At 3:13pm on 28 Jan 2010, Ed wrote:

    I have found several articles published from the 70's on the fermi paradox and the possible expansion of a galactic civilization: E.Jones,"Discrete Calculations of Interstellar Migration and Settlement", ICARUS 46, 328-336 (1981), or "Galactic Civilizations: Population Dynamics and Interstellar Diffusion",W.I. NEWMAN, ICARUS 46, 293-327 (1981), "Temporal Aspects of the Interaction among the First Galactic Civilizations: The 'Interdict Hypothesis'", M.J.FOGG ,ICARUS 69, 370--384 (1987), and others.
    Almost all assume a possible travel speed for interstellar spaceship of the order of 0.1 c (one tenth of the speed of light). There are even some articles which describe a conceptual designs for accelerating a spacecraft to that speed, for example: "Use of Mini-Mag Orion and superconducting coils for near-term interstellar transportation", R.X.LENARD, Acta Astronautica 61 (1-6), pp. 450-458. Of course this is not present day technology.

    The main solutions to the Fermi Paradox on the articles, are generally that or we are alone, or that an insterstellar civilisation is spreading slowly, or they are someway hiding themselves, and others. By the way ,it seems likely that there are not many alien civilisations in our galaxy.

    Many of this articles need a insitutional access in order to be read, but some of them (or similar one) can be found as preprints on arxiv.

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  • 50. At 6:42pm on 28 Jan 2010, Stephen Ashworth wrote:

    Can I please ask Alex (post 42) what reason he has to link UFOs with possible extraterrestrial civilisations? Apart, that is, from the popular science-fictional link?

    I have read a bit about UFO sightings and encounters with supposed aliens. The UFOs don't seem to be coming from anywhere particular or going anywhere particular. The encounters are dreamlike, and the humanoid aliens and their supposed activities are to me unconvincing. There is certainly a very strange phenomenon going on here, but what is there to link it to interstellar travel?

    Stephen
    Oxford


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  • 51. At 01:58am on 29 Jan 2010, Alex wrote:

    Hello Mr Ashworth,

    First of all I want to thank you for taking the time to read my comments on the subject of possible intelligence in the universe. The UFO topic is one which I believe needs serious scientfic study. While I agree with you that UFO's might not come from some distant star then the alternatives from where they come from are few. Maybe they are interdimensional vehicles or possibly something that has come through some sort of time warp! Yes many UFO's are either natural phenomenon or just outright hoaxes or maybe experimental military aircraft. However there are enough unexplained incidents in which credible people have come forward and stated that what they saw could not have been manufactured here on earth. These sightings go back to before World War II. There is a book which I would like to suggest to you. It is entitled Above Top Secret The Worldwide UFO Cover-up. It's written by British author Timothy Good. It has a foreword written by the former British Chief of Defense Staff Lord Hill-Norton,G.C.B.

    This book was quite enlightening to me. It doesn't talk about little green or gray men. It does go over the history of this subject which even today is still perplexing. In the end we both agree that this is a very strange phenomenon. What they are, who they are and where do they come from is the big question. I don't think its science fiction. There are former NASA astronauts who have come forward claiming there is truth to this topic. We have former military personnel who have come forward saying these things knocked out power to a nuclear missile site. Then you have pilots, both commercial and airforce who have had encounters with UFO's. Bottom line is these things exist. They exhibit intelligent control. The media usually sweeps the stories under the carpet or files them into the nonsense section. I think maybe we should spend some of the funds we allocate to SETI to research this (UFO) phenomenon which is right here within our grasp. I am not talking about another project bluebook or condon report. A new research study conducted by civilian scientists from around the world. Some countries are looking into this already as I said in my previous post. The French released an interesting document called the COMETA report in July 1999. It does suggest that there is an extraterrestrial hypothesis to this subject.



    Alex
    Redmond,WA
    USA

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  • 52. At 09:43am on 29 Jan 2010, Jonathan Amos wrote:

    If we were to discover microbial life - on Mars or Enceladus, say - how would that change our thinking about the prospects for intelligent life elsewhere in the Milky Way and beyond? Maybe it wouldn't change anything: perhaps life is abundant in the Universe, just not intelligent life. But then me thinks evolution would inevitably experiment until it found the complexity of intelligence... somewhere, sometime.

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  • 53. At 4:33pm on 29 Jan 2010, wrongstuff wrote:

    Reading comments like 'what would aliens think if they see the early TV broadcasts about wars etc' and 'would they come kill us so that we don't infect other worlds' makes one think:

    1. Why would the aliens be any different than us? The images they see may look normal, like they are on this planet.
    2. Why would they care to intervene?
    3. What makes you think that if they intervene they'll treat us any better than humanity treated the new-found lands in the 15th-16th century. And hey, we're the same species...
    4. Maybe they will feel threatened (what makes you think they would understand that we are fighting each other, and not threatening the universe?)

    Another thought is what makes people think that civilizations last for too long and evolve to an extend to be able to travel the universe like startrek? The fact that the human history is ~3000 years, doesn't necessarily mean there will be "year 5010"..

    If you hope that some ET super civilization will solve our problems down here, I think you'll wait for a loooong time..

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  • 54. At 10:52pm on 30 Jan 2010, Mark Iliff wrote:

    It amazes me how many of these posts exude absolute certainty about the unknowable...

    Suppose one of the following were true:
    1) We are the first of what will become many civilisations (well *somebody* has to be)
    2) Drake's 10,000 civilisations all evolved in exact synch, and none of the others is closer than 100 light years
    3) There is another civilisation about 100 light years away, and its reply has just been sent.
    Would there be any evidence we could observe right here right now? Obviously, no.

    I interpret that as a strong case for continuing to be inquisitive.

    µ

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  • 55. At 9:14pm on 31 Jan 2010, Ed wrote:

    I think is quite likely that, unless life is really very common in the universe, other civilizations (if they exist and are not too far, but what is "far" depends on their technology) may have already spotted Earth as an interesting place (as life may be present). They may not know that a technological civilization is present (but this depends also on their technology and how far they are). We, at the beginning of our space era, are planning space probes (kepler probe and other planned mission) to discover exoplanet similar to earth, and use spectroscopic measurements in order to understand if life is present. And we are just at the beginning!

    I still think that making a better telescope may be easier and cheaper than building a interstellar spacecraft. Nobody will send spaceships to other stars without knowing what they are going to find (they may not know every single detail of the target system, but they will know the main planets, etc.).

    With a simple back on the envelope calculation you can find that an interferometer with a baseline of a few AU you can spot details of the order of a few meters at 100 light year of distance (yes, there is the problem of the light from the main star, and a lot of other problems, so I may be wrong of some order of magnitude, but we are speaking of a very old civilization that at least has spent a lot of its time to understand the universe).

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  • 56. At 6:03pm on 02 Feb 2010, Stephen Ashworth wrote:

    Jonathan, to suggest an answer to your post 52: I don't see that the discovery of microbial life elsewhere in our Solar System would in itself imply that alien intelligent life was common. As I said above in post 43, on its own terms, the universe is still young. Microbial life could be widespread throughout many galaxies, yet intelligent life may only have so far evolved on one planet every few galaxies.

    Just as there is a huge gulf between no life and microbial life, so there is another huge gulf of complexity between single-celled and multi-cellular life and intelligence. This gulf can only be crossed by haphazard, random evolutionary development -- the dinosaurs had hundreds of millions of years to develop intelligence but failed to do so. Early Homo (and also Paranthropus) just got lucky because of the way species behaviour, combined with geography and climate change, happened to conspire to put a premium on brain growth.

    Prof Barrie Jones, author of a recent book on the subject, recently gave a talk in Oxford. He thinks that there has been plenty of time for earthlike planets to form and beings like us to evolve. I disagreed with him then, and still do so now.

    I find it fascinating that this debate is closely linked to a person's views on our own human future. If you are, like me, optimistic about technology and expansion into space, then your view of the human future is one of interplanetary colonisation over the next few centuries, and ultimately interstellar colonisation, which could take our (post-human) descendants all around the Galaxy in perhaps 50 million years of growth -- a long time to us, but a short time on the evolutionary timescale. One would then expect alien civilisations to do the same. Therefore the fact that they are not here yet, combined with the low likelihood of two civilisations appearing within the same 50 million year period in one galaxy, indicates that we are very probably the first civilisation to appear (or that earlier ones failed to make the evolutionary leap to spacefaring cultures, and fell into decline and extinction as a consequence).

    If, on the other hand, you believe that we should renounce further technological and economic growth, or that the limits to growth on Earth will soon force us to do so, and that we should live peacefully in harmonious balance with nature in a zero-growth, one-planet, society, as many people do, then one would expect alien civilisations to have done the same. One then comes up with the prospect of maybe thousands of civilisations in our Galaxy, able to contact each other by radio or laser, but forever barred from actual physical contact by the enormous barrier of interstellar space.

    Two different ways of explaining the lack of any tangible evidence of alien macro-engineering projects in our Solar System or in any neighbouring planetary systems!

    If we do discover microbial life under the surface of Mars, Europa, Enceladus or anywhere else, I shall therefore go on believing that advanced, multi-cellular, intelligent life is rare in the universe, and others will go on believing that it is common.

    Stephen
    Oxford.

    P.S. Alex, thank you for your reply and book recommendation.

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  • 57. At 8:26pm on 05 Feb 2010, phil the fish wrote:

    But ET has made contact, well that is according to this month’s bulletin from ‘The Disclosure Project’, the bulletin says “…in fact, SETI has actually detected signals from other civilizations and has covered up the data! A SETI insider revealed this fact to Dr. Steven Greer and Dr. Greer broke that news in an interview with Art Bell on ‘Coast to Coast AM a few years ago, though he came under heavy criticism because he refused to identify his reliable source, to whom he promised anonymity”.

    The Bulletin also says that the project has already made contact with ET using a number of advanced protocols.

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  • 58. At 10:02am on 06 Feb 2010, feenicks wrote:

    In answer to Giles in post 46 regarding the question 'How does life appear in the first place?'
    I believe that if a question or mystery can be solved or explained using scientific principles then there is no need to invoke spiritual solutions.
    The 1978 Nobel Prize winner Peter Mitchell proposed that life may have developed from the chemical conditions in certain environments.
    On early Earth these conditions were present in the structures built by particular types of undersea vents called alkaline vents.
    The rock that was formed by these vents had temperature gradients, a source of raw material in the water emanating from the vent and very small channels and micrometre sized pores that combine to form the perfect conditions (including the very molecules necessary for life) for life to emerge.
    Although it may be impossible to be sure of the exact processes that produced the first life forms (though even that isn't a given), if there is at least one pathway that can be demonstrated then that is enough to reasonably assume that life is a natural chemical process that arose from the conditions on early Earth.
    Oh yes, as far as your assertion 'evolution isn't quick enough to out-flank chaos'?; the ability of evolution to effect change at a speed that can explain the development of biological features e.g. eyes, ears, brains etc. and species is actually well documented. The scientific community accepts biological evolution as a fact and the only theories are the ones that attempt to describe different elements in the evolutionary march of life on our planet.

    As far as ET is concerned?
    Since the advent of the Big Bang 13.7 billion years ago:-

    1) It took several generations of star formation and destruction to produce the concentrations of elements necessary for rocky planets to be able to form.

    2) It also took as much as 3.8 or more billion years for intelligent life to form here and it is by no means certain that the intelligence is all that easy to achieve, even from a highly complex central nervous system and may not hit the right genetic formula for many more billions of years, if ever.

    3) And now that we are here finally and looking for our fellow thinkers out there we have to wait on that pesky limit of the the speed of light to extend our search in an ever increasing bubble.

    Well we may get VERY lucky and get an indication tomorrow but the simple fact is there is such a large volume out there to hide in, we may be beaten by the sheer distance to another intelligence. Any signal we could reasonably send or receive may be attenuated and interfered withso badly that we miss it.

    So even though I think the chances of a positive result are very low, the value is in the search in that simply imagining the possibility of beings able to communicate with us is healthy as it draws our minds to expand into the space we create and ask the questions our curiosity demands.

    The only way to be sure is to go out there as quickly as our technology will allow. Now THAT's an adventure.

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  • 59. At 10:09am on 06 Feb 2010, feenicks wrote:

    To 'phil the fish' in post 57, I run SETI on my computer and have for many years now. I know what an artificial signal would look like if it appeared in the graphics of the screen saver.
    They must be talking when I'm not looking.

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  • 60. At 1:31pm on 06 Feb 2010, phil the fish wrote:

    To ‘feenicks’ in post 59.
    Doesn’t the SETI scheme run over tens of thousands of computers world wide and not just yours? Even if you were lucky enough to own the computer that processed the signal, you still might not see it unless you were watching your screen saver the whole time. If you went out to make a cup of tea for instance you would miss it and never know. So in the end, it might well have been your computer but who can tell?

    I relayed what Dr. Greer has reported in the latest ‘Disclosure Bulletin’, the same Dr’ Greer who briefs heads of security as well as the presidents in the US.

    President Obama knows of the state of play as did Clinton and Bush according to Dr. Greer. If you like to know more then I suggest you watch the talk that he gave at a conference in Barcelona last summer and study the presidential briefing document.

    YouTube usually only allows 10 minute clips on their site but occasionally lets a longer uninterrupted length of program-
    http://www.youtube.com/watch?v=f0oLJNfs_rM&NR=1
    1hour10mins

    The Presidential letter with links to their PDF downloadable Obama Briefing Document-
    http://www.disclosureproject.org/EmailUpdateOctober242009.htm

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  • 61. At 10:58pm on 11 Feb 2010, James wrote:

    59. At 10:09am on 06 Feb 2010, feenicks wrote:

    To 'phil the fish' in post 57, I run SETI on my computer and have for many years now. I know what an artificial signal would look like if it appeared in the graphics of the screen saver.
    They must be talking when I'm not looking.
    ------------------------------------------------------------------------

    You run SETI @ Home. This data that you get on your pc's sort through isn't gathered live! It's already been recorded on tapes in Puerto Rico, then sent to Berkeley (in the USA) via courier. The data is uploaded to the net & then distributed to pc's all around the world for 'processing'.

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  • 62. At 12:45pm on 14 Dec 2010, Arnie_Aardvark wrote:

    Actually Humans were genetically engineered by aliens to provide a slave workforce to mine for gold. Contact has been mad just not on a worldwide scale, that will happen after certain events have occurred on Earth in the near future.

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  • 63. At 1:37pm on 14 Dec 2010, pov wrote:

    I agree with Paulo. IMO This is one area in which the arrogant and parochial approach of much mainstream science is glaring.

    The idea that ETs would be life-forms that match what humans currently know as life seems to be something that had its' origin in Judeo-Christianity.

    Whatever the basis, the idea is inane.

    It's quite possible that humans have encountered ETs and been unaware of it because those forms lie outside the current "normal" range of sensory perception.

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  • 64. At 1:40pm on 14 Dec 2010, pov wrote:

    beastless,
    I think you're missing the point. However telepathy and OBEs were discovered and verified long ago.

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  • 65. At 2:28pm on 14 Dec 2010, Eric_M_Jones wrote:

    Here's one possible answer to "Where are the Aliens?":

    There are about 4 x 10^22 stars in the universe. On average there are 2 x 10^11 galaxies, each containing 2 x 10^11 stars. Let's assume there are 20,000,000,000 intelligent, technological, communicative, scientific, cultured civilizations distributed across the universe.
    This would mean, on average, there would not be another alien civilization in this galaxy, nor in the next closest galaxies surrounding ours.

    The universe is a very big place.

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  • 66. At 6:14pm on 14 Dec 2010, RevJohn wrote:

    @1. At 9:17pm on 25 Jan 2010, Paulo wrote:

    "Scientists assume that civilizations would comunicate by radio waves. This is a childish assumption.

    Very advanced aliens could certainly communicate with much radical ways of communicating, like telepathy or who knows other faster than light ways."

    Telepathy is easy. It is just a modem and a phone inserted into the ample free space in the skull and connected to the brain. True, we probably can't do it well enough for it to be commercial today, but - assuming technological change continues for a while - we should be able to in another decade or so. Possibly sooner.
    Once we can "voice-link" and "text" from skull to skull, this planet will become a very much quieter place.
    Well, slightly quieter. There will still be the radars.

    The cosmos is a huge place and it is very old and the jump from single-celled goo to Voyager and "Star Trek" takes only such a short time, so where are all the aliens?
    Short answer? Here.
    And you just know that means there now follows a *long* answer:

    Recipe for velociraptor curry: first, evolve a velociraptor. Second, evolve some spices. Next, evolve a cook.
    For the first few million years of the cosmos, there were no tiny, stable stars like ours, only massive, muckle great things that lived for weeks and blew up. These Population III stars were incapable of having planets, not only didn't they last long enough, they also were made only of hydrogen, helium and a very, very tiny smattering of the other hundred elements. The primordial makings of the "Big Bang". Had these stars been followed by worlds, they would have been Jupiters, only bigger.
    When the giants of the breaking dawn of the cosmos blew up, they created all the other elements and spread them into the gases that made up the next generation of stars. These were "dirtier", they condensed out of clouds containing carbon and iron and all that good stuff.
    Eventually, these, too, died. Some of them. The largest, hottest and shortest-lived. They polluted the star clouds with even more calcium and thalium and copper.
    Many generations of supergiant stars later, the dusty clouds were polluted enough to allow stars like Sol to form attended by rocky worlds, tiny dust motes of worlds with silicon and aluminium and oxygen.
    That takes a while. Rocks like Earth were probably not even possible until quite recently.
    Relatively speaking.
    When the Earth condensed, it took a while, a million years or so, for life to evolve. It took another thousand million years or more for life to jump from single-celled goop to multi-cellular things like velociraptors, spices and cooks.
    Life on Earth was *happy* as goop. It was happy as goop for a very, very long time. Then, just recently (a few hundred million years ago), life experimented with the ideas of sex, death, organs, recipes for curry and all the other goodies we recognise as essential for parties. (We're still not sure if any of those innovations were "good ideas" or not.)
    There arises out of this rambling two points: it takes a while to evolve dirt, to collect enough dirt to make worlds and to then evolve spices, and life is generally quite happy to live as bacteria and viral spirals. Cooks are a very late specialism, an experiment that could well prove to be detrimental to the long-term survival of life as a whole.
    So, where are the aliens? Here. We are them. Earth just happens to be the first planet in the entire universe to be able to, and to eventaully evolve life. More, it it also the only planet in all of those galaxies full of stars to harbour what we think of as intelligent, multi-cellular life. (The multi-cellular is pretty much a given, the jury is still out on the "intelligent".)
    Why? Why not? Some planet had to be first. It happened to be this one.
    There are no great huge fleets of reptilians on the way to steal our water (and that always bugged me, if they need water, what's wrong with Mimas? Or Enceladus? Enceladus? Hmmm). There are no Rama style probes floating through the galaxies. There are no machine-worlds, Cylons or Martians. Not until humans get out there and become them.
    We are the first. We are The Ancients. We are the builders of stars and makers of worlds. The Children of Earth will be the inheritors of the universe.
    Scary thought, isn't it?
    The idea that, once we kill life on this one tiny little rock, there will never again be any anywhere in all the universe? The antithesis of that would be the Seed of Earth blowing in the currents of space to fill all the worlds with our song.
    There are no aliens until we go out there and become them.
    {Shrug} It's one explanation.
    The universe is a very big place, but it is so very young, and its Dawn is still barely beginning.
    We should go and greet it.

    Oh, and : Doris and David Jonas. "Other Senses, Other Worlds." Briarcliff Manor, NY: Stein & Day, 1976. 240p. $25.00 cloth; $3.95 paper.
    A truly lovely book. It should be required reading for anyone writing SF.


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  • 67. At 6:54pm on 14 Dec 2010, OETKB wrote:

    There was an interesting paper posted on the Carnegie Mellon exoplanet directory a cule of years ago entitled 'correlation between stellar metalicity and planet formation.' (I may have spelt metalicity wrong!) Basically the claim was that only stars with heavier metallic elements present appeared to be capable of forming solar systems. This was based on results form the exoplanet search, so seemed to deserve a degree of credence.
    The threshold seemed to be iron, only stars with an iron line in their spectra could make planets. It's a fairly straightforward conclusion, planets are formed by residue from the stars primordial nebula coalescing and the material needs to be sufficiently dense to do this. All well and good so far.
    But it's only this current generation of stars that have that predominance of iron, previous generations had burned by fusing lighter elements; the progression towards burning heavier ones is known to be a natural part of stellar evolution. Tentative conclusion 1: - only the current generation of stars are capable of producing planets and therefore life.
    Looking at Fermi's paradox; Enrico Fermi did a back of an envelope calculation that suggested that for a space-faring species to travel length and breadth of the milky way would take 50 - 100 million years (sub-light, in a kind of rise and fall of the Roman empire series of diasporas). So we as a species heave only been around a few hundred thousand years - and we're still stuck on a four billion year old planet. The implication of that might just be - life is only currently emergent in the universe.
    Tentative conclusion 2: Watch the skies! ET might only just be getting his act together! ;)

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  • 68. At 7:00pm on 14 Dec 2010, justin de shed wrote:

    1.) They are far less advanced than we are.

    2.) They are far more advanced than we are, know where we are and sensibly decide to let sleeping dogs lie.

    3.) Their science and technology has branched out explored and developed in entirely different directions to our own. Which could also apply to 1. and 2. This I think is very likely.

    Personally I have to laugh my socks off at the sheer arrogance and ignorance of people calling themselves scientists on this planet earth. Using so called 'facts' to back up what are no more than facile suppositions.
    We have (presumably well respected) high profile lecturers now regularly quoting theory as if it were fact, getting angry and annoyed if anyone should question one word they utter.
    A sad state of affairs for progress and as good a reason as any for 2 and 3, to stay well clear of this hopeless case.


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  • 69. At 7:42pm on 14 Dec 2010, Alan wrote:

    If there are Aliens out there that are 1000 times older than us humans, 1000 times more intelligent and a 1000 times more curious. They still cannot reach us because of the distant they are from us and the speed of light, which cannot be reached or passed. So surely E= MC2 means that we will never meet. Shame, but there it is.

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  • 70. At 9:04pm on 14 Dec 2010, Ron C wrote:

    Frank Drake can convince himself all he likes about there being extraterrestrial life outside of this planets orbit. Does he mean, of the Starship Enterprise kind, the down your throat and through the Sternum "Alien" sort, or of a silicon based new kind of life we can`t imagine exists, exactly imagination. Is he suggesting there are thousands, maybe millions of planets out there, that are of an ideal kind that can sustain and have breeding on it with just a few intelligent building spore types of extraterrestrial life-probable, but not exactly the ideal chess playing partner with. As for full blown up and running civilations well he can believe all he likes, he has`nt me on board on that one. There is nothing to suggest nothing that we are other than alone. I think when we are talking about 100,000 light years across and this is just our Milky Way. What or who would be interested in our bit of dust and if they were would they not have been before this, as for ah! they have been here and we do`nt know about it which means they hav`nt, or they are here and keeping mum about it. What logical resaon could the theorists please explain to me why they shoukld do this. Not a footprint, not a single piece of debris, or communication exists to prove otherwise, what a waste of time Frank is having with his life, better still does he have one?

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  • 71. At 4:32pm on 16 Dec 2010, marcos anthony toledo wrote:

    Extraterreatrials would not use radio signals because it's to slow it's a not in a bottle and they have been here for a long time most likely below the sea monitoring are behaveuor and have their human agents handing them all the information they desire plus what ever human lab rats they need and enjoying the show we unknowingly put on for them. They could also be controlling us thru reglions to keep under control and prevent us from leaving the solar system and competting with them for the resoures of the galaxy.

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