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Author Topic: There's no one out there!  (Read 57868 times)

justboatonic

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Re: There's no one out there! - why our solar system may be unique.
« Reply #300 on: April 01, 2010, 10:57:31 PM »

http://www.newscientist.com/article/dn18719-runaway-star-may-have-spawned-the-solar-system.html

The solar system may have been born inside the remains of a single star that ran away from its family, rather than from a tight-knit clan of stars. If so, it may be more unusual than previously thought.

Meteorites that contain bits of rock called calcium-aluminium-rich inclusions suggest that the solar system may have formed very quickly from the ashes of other stars. That's because the inclusions formed with the radioactive isotope aluminium-26, which is forged inside stars tens of times as massive as the sun and decays with a half-life of only 720,000 years.

Such massive stars tend to form in clusters, and they shed material in roiling winds that can cool down and seed planetary systems.
Too hot

But Vincent Tatischeff of the National Center for Scientific Research in Orsay, France, and colleagues suspect a massive star cluster would have been have been so hot that most of the Al-26 would have decayed before planets could congeal.

Instead, they suggest the solar system sprang from a solitary star's ashes, which could have cooled more quickly. To account for the amount of Al-26 observed in meteorites, the star would still have had to be massive, meaning it probably formed in a clutch of other stars.

At some point, it may have been flung out of its birth cluster by gravitational tussles with its siblings or the explosion of a companion. "The scenario may look complicated, but we think it is the most likely origin of the aluminium-26 in the solar system," Tatischeff says.
Ocean worlds

As it zipped through interstellar space, the star would have released Al-26 in winds, forming a shell of material around it. When the star later exploded, its remains would have slammed into this shell, creating a turbulent region with areas dense enough for the sun to form.

Tatischeff says most of the galaxy's planetary systems may not have formed as quickly as ours, since many probably arose from clusters. This makes them likely to have lower levels of Al-26, which generates heat as it decays. The cooler temperatures may have led rocky planets to take a different evolutionary path to Earth, perhaps becoming ocean worlds.

Eric Gaidos of the University of Hawaii at Manoa did preliminary work on the possibility of a runaway star parent last year, but says the single-star scenario still has trouble explaining how hot gas from the star could mix with surrounding material efficiently enough to form the solar system quickly. "We have yet to deal with the really tough nuts that have to be cracked," Gaidos says.
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justboatonic

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Re: There's no one out there!
« Reply #301 on: April 14, 2010, 08:52:10 PM »

More evidence our solar system may not be the 'model' for other systems.


http://www.timesonline.co.uk/tol/news/science/space/article7096677.ece


Distant planets that orbit the wrong way around their parent stars have been observed by astronomers, in a discovery that challenges prevailing theories of planetary formation.

All the planets in our solar system orbit in the same direction as the rotation of the Sun — anticlockwise — and standard explanations for their formation suggest that this model should apply whenever planets form from a disc of dust around a star.

Research presented yesterday at the Royal Astronomical Society’s annual meeting in Glasgow, however, has now indicated that this is not so.

A team led by Andrew Collier Cameron, of the University of St Andrews, has found six distant “exoplanets” that circle in the opposite direction to their host stars. “The new results really challenge the conventional wisdom that planets should always orbit in the same direction as their star’s spin,” Professor Cameron said.

“Our picture of planetary formation and migration may have been coloured by the simplicity of our own solar system.”

Amaury Triaud, a doctoral student at the Geneva Observatory who was a member of the research team, said: “This is a real bomb we are throwing into the field of exoplanets.”

Standard theories of solar system formation hold that planets coalesce out of protoplanetary discs of dust and gas that spin around a star’s equator. As these discs rotate in the same direction as the star spins on its axis, planetary orbits ought also to follow this pattern. This is what happens in the solar system, where all eight of the planets orbit in the same direction and in roughly the same plane.

The new observations, however, have shown that this model does not always apply, at least to solar systems that contain “hot Jupiters”, or gas giants that orbit very close to their central star.

Of 27 hot Jupiters that were examined in close detail, more than half were found to have orbits that were misaligned with the rotation of their parent stars. Of these, six planets, of which two are newly discovered, orbit in the opposite direction to the star’s spin.

Hot Jupiters are known to form in the outer reaches of solar systems and then to migrate inwards. It had been thought that this was caused by the gravity of other parts of the planetary disc.

Professor Cameron said that the planets with a retrograde orbit must be explained by a different phenomenon: the influence of gravity from more distant objects, typically nearby companion stars.

These would throw gas giants into highly eccentric orbits, causing a gravitational tug of war between two stars that could flip their orbital alignment.

This model also suggests that no Earth-like planets could survive in solar systems of this type.

Didier Queloz, of the Geneva Observatory, another leader of the research team, said: “A dramatic sideeffect of this process is that it would wipe out any other smaller Earth-like planet in these systems.”
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dreadnought72

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Re: There's no one out there!
« Reply #302 on: April 30, 2010, 08:49:05 PM »

Bored and with an hour or so, I've brewed up the Drake equation as a Flash widget for those wanting to play the odds:

html page

direct swf page (may not work for some).

Drag the green buttons - and be alarmed at the results!

Note: 7 is the approximate rate of star production in the galaxy. It's the only fact known with any (i.e. not much) confidence.

Andy

edit: and if the average distance between civilisations is greater than the duration of those civilisations, then they're all dead.

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justboatonic

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Re: There's no one out there!
« Reply #303 on: October 21, 2010, 08:15:29 PM »

More eminent people starting to come to the same conclusion!

http://www.newscientist.com/article/dn18734-why-complex-life-probably-evolved-only-once.html

The universe may be teeming with simple cells like bacteria, but more complex life – including intelligent life – is probably very rare. That is the conclusion of a radical rethink of what it took for complex life to evolve here on Earth.

It suggests that complex alien life-forms could only evolve if an event that happened just once in Earth's history was repeated somewhere else.

All animals, plants and fungi evolved from one ancestor, the first ever complex, or "eukaryotic", cell. This common ancestor had itself evolved from simple bacteria, but it has long been a mystery why this seems to have happened only once: bacteria, after all, have been around for billions of years.

The answer, say Nick Lane of University College London and Bill Martin of the University of Dusseldorf in Germany, is that whenever simple cells start to become more complex, they run into problems generating enough energy.

"It required a kind of industrial revolution in terms of energy production," says Lane. "[Our hypothesis] overturns the traditional view that the jump to complex eukaryotic cells simply required the right kinds of mutations."

"It is very, very convincing, in my opinion," says biologist John Allen of Queen Mary, University of London, on whose work Lane and Martin have drawn.

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Lord Bungle

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Re: There's no one out there!
« Reply #304 on: October 22, 2010, 12:07:20 AM »

As Douglas Adams said the universe is infinite and there is only a finate amount of people on this planet, now if you divide a finate number by infinity the number is so near zero as not to matter, this means no one exists and anyone you do meet is a figment of your deranged mind. So that explains me  {-)
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Bowwave

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Re: There's no one out there!
« Reply #305 on: October 22, 2010, 03:31:25 PM »

All you need for life in another solar system  is a couple of gas giants, a goldilocks  planet , water , lightning and it worked for  earth .so there is no reason to assume the same or similar pathway to intelligent species  can not be replicated somewhere else.
Bowwave
 %)
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justboatonic

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Re: There's no one out there!
« Reply #306 on: October 22, 2010, 06:38:40 PM »

To be fair, I have to say I dont quite agree with the comments about intelligent life in the universe. The universe is so big that even I consider the chances of at least one other intelligent civilisation to be better than evens.

However, I do think we are probably the oldest, most advance intelligent civilisation in the Galaxy right now. Just thought I'd clarify that for you know who  :}
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dodgy geezer

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Re: There's no one out there!
« Reply #307 on: October 22, 2010, 06:54:38 PM »


More eminent people starting to come to the same conclusion... intelligent life – is probably very rare....


I would refer you to Clarke's First Law..



..However, I do think we are probably the oldest, most advance intelligent civilisation in the Galaxy right now...


On current showing that would be very bad news for the Galaxy.... {:-{ {:-{
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malcolmfrary

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Re: There's no one out there!
« Reply #308 on: October 23, 2010, 09:25:12 AM »

With even the nearest vaguely possible contender (and the possibility factor needs to have its vagueness expressed in scientific notation) being as far away as it is (50 light years was it?), our earliest coherent transmissions have only been hitting it for a few years, and their instant reply might be part way back.  IF there is anybody there listening, and interested enough and equipped to do so.  IF they are within the same development/technology window as us.  If they haven't done what we are heading for, sending our radio signals down optical cables so that they revert to being a non-emissive planet, or have the bubble of their civilisation pop, and revert to a non-technical society.
The galaxy might be awash with spandex-clad lady spacefarers, about the same size as us, but the over-riding practicality remains that unless one of them (or us, for that matter) really has a viable means of travelling faster than light, with our life expectancy, meaningful contact is not a possibility, so for all practical purposes, they are not there.
Other life is very probable, though.  A planet in the "goldilocks" region, with liquid and weather will probably have lightning (recently spotted on Venus), and thats basically all that is needed to start the ball rolling.  Keeping it rolling and in the "right" direction is another set of coincidences altogether.  Its a long way from having caustic soda and salty water and a supply of electricity to having a Lego set, but that is a very short trip compared to evolving us.
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Bowwave

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Re: There's no one out there!
« Reply #309 on: October 23, 2010, 02:13:21 PM »

We as a species are rather arrogant  assuming that intelligent life forms are a rarity in our Milky Way.  But how many life forms have developed here on planet earth that either have gained a level of Intelligence or thought processes not so different to ours.    Nature works on random numbers and chaos is the driver; if an event takes place such as a mass extinction then nature will evolve to use this to its advantage. The single great leap that has marked species out as an advanced life form is the development of technology. Even the simple act of taking a bone fragment and being able to fashion that fragment into an implement with the thought process that that implement will do a job is probably a regular occurrence through out the cosmos. Self awareness  has  always been a marker to defining the development of  our species to that of others but there is even research to indicate that other species on our planet are self aware.    Given enough time almost any species with  a similar form to ourselves  can evolve.   It’s inconceivable that nature would develop only one intelligent species with the thought processes of humans . The big  question  and there is always a big  question ,  will any intelligent self aware species be around long enough to perfect the ability to communicate beyond its home world?   Equally our species has evolved rapidly on a cosmic scale so once again there is no reason to believe that this random occurrence is not universal.
Bowwave
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malcolmfrary

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Re: There's no one out there!
« Reply #310 on: October 25, 2010, 10:14:45 AM »

http://dingo.care2.com/cards/flash/5409/galaxy.swf
Says it all, but only if you have the sound turned on.
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Bowwave

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Re: There's no one out there!
« Reply #311 on: October 25, 2010, 11:49:06 AM »

http://dingo.care2.com/cards/flash/5409/galaxy.swf
Says it all, but only if you have the sound turned on.
It certainly does  %% :-))
Bowwave
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justboatonic

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Re: There's no one out there!
« Reply #312 on: October 25, 2010, 08:26:15 PM »

With even the nearest vaguely possible contender (and the possibility factor needs to have its vagueness expressed in scientific notation) being as far away as it is (50 light years was it?), our earliest coherent transmissions have only been hitting it for a few years, and their instant reply might be part way back.  IF there is anybody there listening, and interested enough and equipped to do so.  IF they are within the same development/technology window as us.  If they haven't done what we are heading for, sending our radio signals down optical cables so that they revert to being a non-emissive planet, or have the bubble of their civilisation pop, and revert to a non-technical society.

Not sure about the distance thing. But, if there was an intelligence 50 LY away capable of hearing or picking up our transmissions, we'd most likely have picked up theirs by now. Course the oft response is they are far too intelligent to bother about us or use a communications medium we havent discovered yet.

But, Ocams razor prevails. There's unlikely to be another advanced civilisation in the Galaxy right now which is why we dont see them, dont hear them or find any of their artefacts.



Quote
The galaxy might be awash with spandex-clad lady spacefarers, about the same size as us, but the over-riding practicality remains that unless one of them (or us, for that matter) really has a viable means of travelling faster than light, with our life expectancy, meaningful contact is not a possibility, so for all practical purposes, they are not there.
Other life is very probable, though.  A planet in the "goldilocks" region, with liquid and weather will probably have lightning (recently spotted on Venus), and thats basically all that is needed to start the ball rolling.  Keeping it rolling and in the "right" direction is another set of coincidences altogether.  Its a long way from having caustic soda and salty water and a supply of electricity to having a Lego set, but that is a very short trip compared to evolving us.

I doubt it. Roughly 10% of stars in the galaxy are like our Sun, not too big  so as to have a short life, not too small so as to give out insufficient heat and light. Likely hardly any of those 10% of Sun like stars will have a solar system like ours and even if some did, its unlikely a terrestrial planet like earth would be in the habitable zone ad infinitum etc, etc. I dont have issues with microbial life eeking out an existence on Mars, Europa or some other place in the Galaxy. But I find nothing other than hope to suggest intelligent life is out there and certainly nothing in numerate quantities.
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justboatonic

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Re: There's no one out there!
« Reply #313 on: October 25, 2010, 09:02:21 PM »

We as a species are rather arrogant  assuming that intelligent life forms are a rarity in our Milky Way.  But how many life forms have developed here on planet earth that either have gained a level of Intelligence or thought processes not so different to ours. 

I dont know how you come to that conclusion. Too many people assume intelligent life is an end product of evolution. It isnt. For example, the planet has been here for roughly 4.5 billion years. Yet were it not for a chance happening 65 million years ago, it is unlikely mammals would have got the foothold they did. And even so, it is only in the last 5 million or less years that apes split into more than one group which saw one branch inexplicably go on to develop 'intelligence' while the other branches died out or did not gain an equal independant level of intelligence.

Now, Im not saying dolphins and some primates dont exhibit some signs of intelligence. They do but clearly it isnt a significant technological intelligence either.

But dont take my word for it, just ask Professor Paul Davies. His book 'An eerie silence' is an excellent read for anyone interested in the search for intelligent life in the galaxy. Microbial life could be common. But that doesnt mean intelligent will follow. Nor does it make anyone who believes intelligent is rare is arrogant.


 
Quote
  Nature works on random numbers and chaos is the driver; if an event takes place such as a mass extinction then nature will evolve to use this to its advantage. The single great leap that has marked species out as an advanced life form is the development of technology. Even the simple act of taking a bone fragment and being able to fashion that fragment into an implement with the thought process that that implement will do a job is probably a regular occurrence through out the cosmos. Self awareness  has  always been a marker to defining the development of  our species to that of others but there is even research to indicate that other species on our planet are self aware.    Given enough time almost any species with  a similar form to ourselves  can evolve.   It’s inconceivable that nature would develop only one intelligent species with the thought processes of humans . The big  question  and there is always a big  question ,  will any intelligent self aware species be around long enough to perfect the ability to communicate beyond its home world?   Equally our species has evolved rapidly on a cosmic scale so once again there is no reason to believe that this random occurrence is not universal.
Bowwave


Given the size of the universe, yes I'd agree that it is highly unlikely intelligence would not have developed at least once in another galaxy. However, given the size of our galaxy which is one of the largest in the local group, I consider it is unlikely multiple instances of intelligence will have developed at the same time here.

But, you allude to there being 'enough time.' And in a way that is why its unlikely multiple intelligences co exist simultaneously. A suitable star only has a finite timespan to provide the warmth and light to allow intelligence to develop and be sustained. Although our sun will likely shine for another 5billion years, it is reckoned only 500 million or so of that is available for intelligence to make use of on this planet before earth starts to become uninhabitable. Suitable stars dont all co exist at the same time therefore suitable planets dont all exist at the same time even if they were all in the habitable zone. And evidence to date still suggests there's no other similar credible example.

Some people use the example of 'insufficient time' as a reason for not finding the elusive SETI signal. But again Prof Davies is not taken in by this. Paul Davies suggests that after 50 years searching, it isnt that no signal has been found due to lack of time rather that it is the methodology employed that is flawed. Or that there really is no one out there!  ;)

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Bowwave

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Re: There's no one out there!
« Reply #314 on: October 25, 2010, 10:41:41 PM »

I recommend you read this it is a sound hypothesis to the idea that intelligent life is universal  and   not at all confined to our planet.
http://www.msnbc.msn.com/id/32403430/
Bowwave
 :-))
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dodgy geezer

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Re: There's no one out there!
« Reply #315 on: October 26, 2010, 09:36:47 AM »


I doubt it. Roughly 10% of stars in the galaxy are like our Sun, not too big  so as to have a short life, not too small so as to give out insufficient heat and light. Likely hardly any of those 10% of Sun like stars will have a solar system like ours and even if some did, its unlikely a terrestrial planet like earth would be in the habitable zone ad infinitum etc, etc....



David Kipping reckons 22.7% F, G and K-types. Here is his estimation which suggests 75m habitable environments (planets or moons in a habitable zone) in the galaxy. You keep saying that something does not exist, but this does not make it so.... http://www.homepages.ucl.ac.uk/~ucapdki/numberofhabs.html



"...But dont take my word for it, just ask Professor Paul Davies.....  Paul Davies suggests that .... there really is no one out there.."


Thanks, I will. It is very odd to see it being suggested that Paul Davis supports the concept that there is 'nobody out there'. He is the chair of the "SETI: Post-Detection Science and Technology Taskgroup" of the International Academy of Astronautics. He suggests that SETI technology should be developed, not stopped. Here is an interview with him last December: http://www.astronomynow.com/mag/1001/PaulDaviesInterview.html


I draw your attention to the following quotes:

" I don’t think we have the sensitivity yet to pick out random radio traffic buzzing between civilisations. What I think is a big lacuna in the search so far is that beacons have not been actively searched for. It is much more probable that we would pick up a multidirectional beacon than random messages between civilisations or domestic radio traffic or anything deliberately directed at us. All those scenarios don’t stack up, but beacons do. We can imagine a long vanished civilisation that has left a beacon, and this could go on for millions of millions of years. There really has been no systematic search for them, and yet we have the technology to do that."


"..I don’t think there is any problem in pursuing radio and optical, but my theme in The Eerie Silence is that we should continue searching for messages because we are set up to do that, but that we should also be looking for the most general signatures of technology right across the board..."

This does not sound like a person who believes that 'we are alone', that the SETI search has been comprehensive and that it is no longer worth looking for evidence of other intelligent civilisations, as you imply....





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justboatonic

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Re: There's no one out there!
« Reply #316 on: October 26, 2010, 11:02:46 PM »


David Kipping reckons 22.7% F, G and K-types. Here is his estimation which suggests 75m habitable environments (planets or moons in a habitable zone) in the galaxy. You keep saying that something does not exist, but this does not make it so.... http://www.homepages.ucl.ac.uk/~ucapdki/numberofhabs.html

That's 3 types of star. Last time I checked, the Sun was only one type. Yet another example of how you attempt to twist a debate.


Quote
Thanks, I will. It is very odd to see it being suggested that Paul Davis supports the concept that there is 'nobody out there'. He is the chair of the "SETI: Post-Detection Science and Technology Taskgroup" of the International Academy of Astronautics. He suggests that SETI technology should be developed, not stopped. Here is an interview with him last December: http://www.astronomynow.com/mag/1001/PaulDaviesInterview.html

Yes. I watched the full recording of his presentation sometime ago. He suggests the methodology SETI is following is flawed. Where have I said davies claims SETI should be stopped? Check out the eerie silence. It may enlighten you ( but probably not!) since in that book he suggests alternate ways to look for SETI! You're absolutely incredible, you know that?

Again, you deliberately misconstrue one of my statements to try and prove your point. Sorry but I cannot help it if you deliberately continue to do this. Read the eerie silence. Davies states that intelligence isnt the natural end product of or goes hand in hand with evolution.

Where have I  "suggested that Paul Davis supports the concept that there is 'nobody out there'."? Answer nowhere. I used Davies in connection with his book where he writes about intelligence and evolution. And no, Im not going to give you direct quotes. But you carry on making stuff up and looking foolish.

Davies suggests in his opinion in the eerie silence that any likely ETI will \ probably be machine based. Now no doubt you'll want to argue what is a machine and what isnt. Go right ahead.

Quote
I draw your attention to the following quotes:

" I don’t think we have the sensitivity yet to pick out random radio traffic buzzing between civilisations. What I think is a big lacuna in the search so far is that beacons have not been actively searched for. It is much more probable that we would pick up a multidirectional beacon than random messages between civilisations or domestic radio traffic or anything deliberately directed at us. All those scenarios don’t stack up, but beacons do. We can imagine a long vanished civilisation that has left a beacon, and this could go on for millions of millions of years. There really has been no systematic search for them, and yet we have the technology to do that."


"..I don’t think there is any problem in pursuing radio and optical, but my theme in The Eerie Silence is that we should continue searching for messages because we are set up to do that, but that we should also be looking for the most general signatures of technology right across the board..."

Where have I said the following of Davies?

Your quote "This does not sound like a person who believes that 'we are alone', that the SETI search has been comprehensive and that it is no longer worth looking for evidence of other intelligent civilisations, as you imply...."

I find it faintly amusing you have to doctor a couple of sentences to try and support your stance. Tell me, do you always twist what people say or write in some vain attempt to prove you are correct? Instead of taking selective parts of sentences then joining them together to make something read differently to how it was originally constructed I suggest you are instead giving your position no credibility whatsoever.

I suppose I could dig out a quote or two from Davies' The Eerie Silence where he says SETI is flawed or that there may be the possibility that we are the only intelligent civilisation in our galaxy right now but no doubt you'd try and spin that he didnt really mean it!
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dodgy geezer

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Re: There's no one out there!
« Reply #317 on: October 27, 2010, 01:40:31 AM »


That's 3 types of star. Last time I checked, the Sun was only one type.


There are lots of ways of classifying stars. Kipping has picked these three divisions (which are next to each other on the Main Sequence) as star classes perfectly capable of supporting planets with liquid water. I assume that is the purpose of this discussion?
 

"..Where have I  "suggested that Paul Davis supports the concept that there is 'nobody out there'."?.."


Your proposition was originally that Earth-like planets are rare or non-existent, and now seems to be that intelligent life is rare or non-existent elsewhere (a proposition which is unlikely to be proven either way in our lifetimes). You cited Davis' book in support of this.

Do I take it that you now believe we haven't looked hard enough or in the right way, and that we should increase or improve our efforts? This is what Davis is saying, which suggests he believes that intelligent life is out there to be found.

My own position is that earth-like planets are relatively common in the Galaxy, and I suspect that where the conditions are appropriate life will develop quite rapidly. We know too little about the development of intelligence to be able to hazard a defensible guess at how common that is, but I would be surprised if it turns out to be a very unusual evolutionary path....



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justboatonic

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Re: There's no one out there!
« Reply #318 on: October 27, 2010, 10:38:07 PM »

There are lots of ways of classifying stars. Kipping has picked these three divisions (which are next to each other on the Main Sequence) as star classes perfectly capable of supporting planets with liquid water. I assume that is the purpose of this discussion?
 
Your proposition was originally that Earth-like planets are rare or non-existent, and now seems to be that intelligent life is rare or non-existent elsewhere (a proposition which is unlikely to be proven either way in our lifetimes). You cited Davis' book in support of this.

Do I take it that you now believe we haven't looked hard enough or in the right way, and that we should increase or improve our efforts? This is what Davis is saying, which suggests he believes that intelligent life is out there to be found.

My own position is that earth-like planets are relatively common in the Galaxy, and I suspect that where the conditions are appropriate life will develop quite rapidly. We know too little about the development of intelligence to be able to hazard a defensible guess at how common that is, but I would be surprised if it turns out to be a very unusual evolutionary path....





Sorry old chap but that doesnt wash. Wriggle on the hook all you want by claiming my proposition was....................

The plain fact of the matter is you cannot produce a scrap of proof to support what you claimed I said about Davies. Once again you clumsily use separate statements to try and make a half baked proposition (which, I may add, is totally incorrect).

My position is clear despite your repeated attempts to spin it other ways. Its just your inability to read English properly (perhaps it is not your first language?).

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dodgy geezer

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Re: There's no one out there!
« Reply #319 on: October 28, 2010, 11:59:25 AM »


My position is clear despite your repeated attempts to spin it other ways....


..then it's a shame you have problems enunciating it.  I really cannot tell from your posts whether you believe that we should increase and improve our search for extraterrestrial intelligence (as Paul Davies argues), or whether you believe that this is doomed to failure and we ought to give up.
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justboatonic

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Re: There's no one out there!
« Reply #320 on: October 28, 2010, 07:30:43 PM »

..then it's a shame you have problems enunciating it.  I really cannot tell from your posts whether you believe that we should increase and improve our search for extraterrestrial intelligence (as Paul Davies argues), or whether you believe that this is doomed to failure and we ought to give up.

Look. I've humoured your pathetic attempts to re write what I have stated in previous posts long enough. You have taken selective parts from different sentences and strung them together to make them read as something else then posed the question 'what do you mean?' or tried to present it as evidence of an about turn on my part.

You seemed a reasonably intelligent person who has an abstract opinion on astronomy and or astrobiology. But Im no longer prepared to play your game. Perhaps you have some hang up after spending almost the equivalent of 200 years computing time trying to find evidence you so desire to prove ETI that, you've lost sight of other people's opinion.

From now on, I'll ignore your rather borish attempts to prove yourself superior and shout down any and every opinion that does not meet yours.
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chingdevil

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Re: There's no one out there!
« Reply #321 on: October 28, 2010, 07:53:26 PM »

Calm down guys lets not allow this to become personal, everyone is entitled to their opinion.


Brian
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justboatonic

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Re: There's no one out there!
« Reply #322 on: October 28, 2010, 07:58:05 PM »

Well, never let it be said I dont recognise the other side of the argument unlike one poster here!

http://www.bbc.co.uk/news/science-environment-11647089

Nearly one in four stars like the Sun could have Earth-sized planets, according to a new estimate published in the journal Science.

A US team has found that on average small, so-called rocky planets are much more common in orbit close to their star than giant planets planets similar in size to Jupiter.

This estimate is based on observations from nearby stars taken by the the twin 10-metre Keck telescopes in Hawaii. These show that 22 of the stars had detectable planets.

The researchers estimated that about 1.6% of the Sun-like stars in their sample had Jupiter-size planets and 12% had so-called "super-Earths", which are between three and 10 times the mass of the Earth.

However, its not all sweetness and light. The proposition is based on extrapolation so the calculation could be wildly out of kilter with fact.

"This extrapolation is the least certain part of our analysis. The true answer might be one in eight or one in two - but we know that it isn't one in 100,"

But according to Dr Robert Massey of the Royal Astronomical Society, most of the worlds they predict exist would be too close to be habitable. Ergo, no ETI on those worlds.
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Colin Bishop

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Re: There's no one out there!
« Reply #323 on: October 28, 2010, 08:00:06 PM »

I wonder if this topic is still being followed by any form of intelligent life.....?
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justboatonic

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Re: There's no one out there!
« Reply #324 on: October 28, 2010, 08:17:18 PM »

Well you dropped by, Colin.  :-))
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