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Author Topic: Kepler mission adds more weight to our solar system not being the norm.  (Read 22600 times)

dodgy geezer

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #100 on: February 11, 2011, 01:52:59 AM »


I find it disappointing that anyone wants to raise religion in this thread. IMHO, it has no place in this thread which was started as a purely 'astrological' one. I could well imagine someone starting a religious thread being, rightly, upset if they started such a thread and astronomy was introduced as an alternate view..........In both this thread and the 'There's no one out there!' thread, I hoped it would be as you say, in plain ordinary language that doesnt get bogged down in too technical explanations or demands. Unfortunately, again, IMHO, one or two notable posters seem to have gone out of their way to do just that ie technical terms and demands of scientific papers to support a number of posts or argue down an alternative view.


I have no problem with anyone who may want to talk about a religious sense of awe when considering the makeup of the universe. But I would disagree if, for instance, that person went on to say that, because of this religious dimension, exploration of the universe should be curtailed. I am thankful that this does not seem to be the case. Similarly, I have no difficulty with anyone who wants to avoid any discussion they consider technical, but I would not accept this being used as a justification to push theories which are technically inaccurate.  And I rather hope that this thread started as an 'astronomical' one....     


These comments are "On 2 February 2011, the Kepler team announced the results from the data of May to September 2009. They found 1235 planetary candidates circling 997 host stars, more than twice the number of currently known exoplanets. This haul included 68 planetary candidates of Earth-like size and 54 planetary candidates in the habitable zone of their star. They estimate that 6% of stars host Earth-size planets and 19% of all stars have multiple planets." ....................Im not going to do the maths but its reasonable to assume that not all those Earths are going to be in the habitable zone of their host star.


Astronomer Seth Shostak has done the maths for you. He estimates that "within a thousand light-years of Earth" there are "at least 30,000 of these habitable worlds." But these are still early days and there seems to be little point in guessing at numbers when we are quite close to getting concrete data.
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Bryan Young

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #101 on: February 11, 2011, 05:53:32 PM »

In truth, I've enjoyed this topic...insofar as I could understand it. Nothing wrong with that, never too late to learn.
The only reaso I brought the dreaded word "Religion" into the discussion was because ever since mankind became sentient he's looked at the skies and "wondered" what it was all about. Various bits of mystique was eventually attached to the heavens, and so all sorts of stuff came about that eventually coalesced into the word "Religion". I wish it had another word in this context! Nothing whatsoever to do with the pomp and ceremony of how "religion" is now practised.
Anyone who has been lucky enough to look up into a full starlit sky....even in this year of 2011...must have had a few moments of private cogitation. More or less on the lines of "What if"?
Theologians, Cosmologists, Physicists and Astronomers all seem to just carry on ploughing their own furrow disregarding other ideas. Perhaps with the exception of people like the late Fred Hoyle who appeared to embrace just about everything. And nothing wrong with that, either. Must have confused the hell out of him though. BY.
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justboatonic

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #102 on: February 11, 2011, 11:08:07 PM »

I have no problem with anyone who may want to talk about a religious sense of awe when considering the makeup of the universe. But I would disagree if, for instance, that person went on to say that, because of this religious dimension, exploration of the universe should be curtailed. I am thankful that this does not seem to be the case. Similarly, I have no difficulty with anyone who wants to avoid any discussion they consider technical, but I would not accept this being used as a justification to push theories which are technically inaccurate.  And I rather hope that this thread started as an 'astronomical' one....     

You once again labour under a misunderstanding. I find that unsurprising given your repeated attempts to hijack this and other threads. But you carry on if you must.


Quote
Astronomer Seth Shostak has done the maths for you. He estimates that "within a thousand light-years of Earth" there are "at least 30,000 of these habitable worlds." But these are still early days and there seems to be little point in guessing at numbers when we are quite close to getting concrete data.

That'll be the same Seth who claims seti will 'discover' the first ETI signal within the next 25 years?  :-))
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justboatonic

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #103 on: February 11, 2011, 11:12:47 PM »

In truth, I've enjoyed this topic...insofar as I could understand it. Nothing wrong with that, never too late to learn.
The only reaso I brought the dreaded word "Religion" into the discussion was because ever since mankind became sentient he's looked at the skies and "wondered" what it was all about. Various bits of mystique was eventually attached to the heavens, and so all sorts of stuff came about that eventually coalesced into the word "Religion". I wish it had another word in this context! Nothing whatsoever to do with the pomp and ceremony of how "religion" is now practised.
Anyone who has been lucky enough to look up into a full starlit sky....even in this year of 2011...must have had a few moments of private cogitation. More or less on the lines of "What if"?
Theologians, Cosmologists, Physicists and Astronomers all seem to just carry on ploughing their own furrow disregarding other ideas. Perhaps with the exception of people like the late Fred Hoyle who appeared to embrace just about everything. And nothing wrong with that, either. Must have confused the hell out of him though. BY.

Yep, me too. Apart from a couple of people spoiling the thread and using comments such as "I would not accept this being used as a justification to push theories which are technically inaccurate."

Methinks someone's brain is off with the fairies again dreaming up such falsehoods.
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Colin Bishop

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #104 on: February 11, 2011, 11:23:26 PM »

I suppose it might not be inaccurate to say 'God knows what the truth of all this is.'

Colin
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justboatonic

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #105 on: February 11, 2011, 11:36:41 PM »

I suppose it might not be inaccurate to say 'God knows what the truth of all this is.'

Colin

Probably. I guess it depends on one's outlook of subjects on message boards. Unfortunately some people want to turn them into a scientific master class or maybe just a vain attempt to prove their superiority rather than accept it for what it is ie a place for debate rather than proving one way or the other with the aid of complex technical argument.

If that's their opine, then perhaps they should stick to places where their technical argument is welcomed and not used as a tool to stifle debate?
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dodgy geezer

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #106 on: February 12, 2011, 01:11:27 AM »

Yep, me too. Apart from a couple of people spoiling the thread and using comments such as "I would not accept this being used as a justification to push theories which are technically inaccurate."

Methinks someone's brain is off with the fairies again dreaming up such falsehoods.

As I recall, this thread started with you claiming that Earth-type planets would be vanishingly rare for a technical reason - the migration of Hot Jupiters. Then you claimed that the early Kepler data showing short-period planets also indicated that Earth-types in the Habitable Zone were rare.

I, and others, pointed out the technical inaccuracies in these assertions. Your response seems to be that this is ruining the thread for you. I see it as preventing opinion and journalist's reports masquerading as proven data...
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justboatonic

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #107 on: February 22, 2011, 08:11:12 PM »

As I recall, this thread started with you claiming that Earth-type planets would be vanishingly rare for a technical reason - the migration of Hot Jupiters. Then you claimed that the early Kepler data showing short-period planets also indicated that Earth-types in the Habitable Zone were rare.

I, and others, pointed out the technical inaccuracies in these assertions. Your response seems to be that this is ruining the thread for you. I see it as preventing opinion and journalist's reports masquerading as proven data...

This is interesting considering the backstroking going on above. And I love the way you try and make out a post on a model boat forum is an attempt, in any way shape or form, definitive of the situation.

Yes, of course I posted below and included a point of reference for people to read. However, you seem to have appointed yourself forum policeman on the subject. Do that if it gives you a sense of purpose in some small way.

The fact of the matter, as I have pointed out numerous times, is, this is a forum for debate. Instead you attempt to turn it into a science lesson.

For reference this is my original post
   
Kepler mission adds more weight to our solar system not being the norm.
on: August 29, 2010, 10:36:56 AM
   Reply with quote
The much vaunted Kepler mission continues to provide evidence that our solar system is tending towards uniqueness rather than the norm.

Prior to Kepler's launch, virtually every exoplanetary system and exoplanets, were hot jupiters. That is, massive planets the size of jupiter or larger and, orbiting their parent star in a matter of days since they were so close to it.

Simulations have shown that where a hot jupiter planet exists very close to its parent star, it must have migrated in from further out. Hot jupiters cannot form close in to a star as there just isnt enough material for them to form. Instead, they must form further out in a system where there is more gas, elements and material required to form planets of their size.

The simulations show where hot jupiters migrate inwards, smaller terrestrial sized planets, if they existed in the system, would be ejected from that solar system.


http://www.telegraph.co.uk/science/space/7966992/Three-vast-planets-found-orbiting-distant-star.html

Now, we have this

http://www.telegraph.co.uk/science/space/8336500/Alien-life-boost-after-Nasa-finds-one-in-two-Suns-has-Earth-like-planets.html

The news came from NASA scientists studying the results from the Kepler telescope which in its first two years in space has found evidence of more than 1,200 planets in orbit around far distant stars.

The early findings suggests that there are triple the number of known planets outside our own solar system - 54 of them are Earth size and in the habitable zones from their suns.

Only two potentially habitable planets have previously been found outside earth's solar system, so Kepler scientists are very excited at finding so many possible candidate planets.


Speaking at the American Association for the Advancement of Science, Kepler chief scientist William Borucki said: "I am really delighted that we are seeing so many candidate planets and that means there is a rich ocean of planets out there to explore.

"For every two stars we are seeing a candidate planet."

The next step is to send out new telescopes to see if the atmospheres of the planets, that are between 30 and 100 light years away, have friendly atmospheres on which life could survive.

It is another big step to prove that a confirmed planet has some of the basic conditions needed to support life, such as the proper size, composition, temperature and distance from its star.

More advanced aspects of habitability such as specific atmospheric conditions and the presence of water and carbon require telescopes that are not built yet.
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Jimmy James

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #108 on: February 23, 2011, 01:18:36 AM »

Kepler was a dunce. every one knows that the Klingon's exist and that the Mars men tried to invade earth but were defeated by earth bound bacteria...I mean Holly Wood cant be wrong !!! Can it??? ... O0 {-) %% ... Seareously ...Do you honestly beleave that We are the only intelagent life form in the whole unaverse.... I think not... the odds are much to long ... How can anyone say there is no life out there when we can't even count the sun's out there let alone the number of planets... This is  the flat earth socitey all over again
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Jimmy James

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #109 on: February 23, 2011, 01:21:40 AM »

Sorry chaps wrong button should have been the spell check
 :D  :embarrassed:  :embarrassed:
Jimmy
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dodgy geezer

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #110 on: February 23, 2011, 11:04:45 AM »


...The fact of the matter, as I have pointed out numerous times, is, this is a forum for debate. Instead you attempt to turn it into a science lesson...



I see no debate on this thread. What I see is a succession of press reports culled mainly from the Telegraph science pages. And a running disagreement about the interpretation of early Kepler data which did not show planets at Earth-like orbits. Your view was that this showed that our system was abnormal and rare - others pointed out that Kepler needed time to find planets in wider orbits. I'm not sure why you think that constitutes a 'science lesson' which ought to be avoided... 

Given that Jupiter takes 12 years to orbit once we will have to wait around 30 years to detect planets like this in Kepler data. The probe is unlikely to last that long. Nevertheless, the data coming in so far suggests that planets  are quite common at all orbits, and I see nothing in the current data to suggest that Earth-like planets in the habitable zone will not be found when enough data has been collected.

Mr James' view that life is likely must wait on more data, of course. Nevertheless, none of the data gathered so far contradicts this possibility, and I anticipate that equipment capable of studying the atmospheres of close Earth-type planets should be available within 10 years...
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Jimmy James

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #111 on: February 24, 2011, 11:26:24 PM »

Thanks D.G.
Jimmy
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dreadnought72

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #112 on: March 10, 2011, 10:47:44 AM »

At last. Some science arrives:

http://xxx.lanl.gov/ftp/arxiv/papers/1103/1103.1443.pdf

The digested results:

For F, G and K-type stars (i.e. those without excessive flares and old enough for life to develop), an Earth-analogue planet (0.8 to 2.0 times the size of the Earth) exists in the habitable zone (defined as 0.95 to 1.37 AU for a solar-luminosity star) ...

... 2.5% of the time.

This number may be revised up or down a little as Kepler works away for the next few years.

But it currently suggests that one in forty stars similar to the Sun have an Earth-analogue.

Over a billion in this galaxy.  %%

Andy

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dodgy geezer

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #113 on: March 10, 2011, 02:00:25 PM »

At last. Some science arrives:

http://xxx.lanl.gov/ftp/arxiv/papers/1103/1103.1443.pdf

The digested results:

For F, G and K-type stars (i.e. those without excessive flares and old enough for life to develop), an Earth-analogue planet (0.8 to 2.0 times the size of the Earth) exists in the habitable zone (defined as 0.95 to 1.37 AU for a solar-luminosity star) ...

... 2.5% of the time.

This number may be revised up or down a little as Kepler works away for the next few years.

But it currently suggests that one in forty stars similar to the Sun have an Earth-analogue.

Over a billion in this galaxy.  %%

Andy




Interesting. Still early days, and I suspect that this was put out fast to gain publicity... but if the figures hold up it suggests that there could be a couple of 'Earths' within 50 LY of us. Lots more 'other' planets, of course, and this calculation does not take satellites of gas giants into account.

Of course, to have a proper discussion here we need to wait until this is reported in the Telegraph....  %)

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dreadnought72

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #114 on: March 10, 2011, 02:08:06 PM »

A couple of Earths within 50ly would be more than I would have hazarded a guess at, myself - but any idea of uniqueness is certainly blown away. Meanwhile this paper's restrictions on the Earth-analogues are quite tight. As you say, they exclude gas giant satellites, and other scientists would certainly include a wider zone for habitability.

Maybe the Torygraph will catch up in a fortnight or so?  ;)

Andy

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dodgy geezer

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #115 on: March 10, 2011, 03:25:07 PM »


A couple of Earths within 50ly would be more than I would have hazarded a guess at, myself...


Based on this atlas http://www.atlasoftheuniverse.com/50lys.html giving 133 visible stars within 50LY - the vast majority F/G/K. That suggests 3 Earths for 120 stars - I knocked one off to give a more conservative estimate. There are lots more low magnitudes, of course, but those are outside the definition...

If we go into more guesswork (rather than calculating probabilities based on volumes!) I might hazard that the nearest one will be about 30LY away. That figure tells us what size of detection apparatus needs to be created to examine an atmosphere at that distance, and hence what budget will be required...


This number may be revised up or down a little as Kepler works away for the next few years.

I suggest it is more likely to be revised up. The paper assumes that Kepler has found all planets that it is capable of so far - if for some reason or another this is not true, then the figure goes up. And it is only calculating for earth-type planets round an earth-type star - practical habitable planets may be found in other configurations. This figure represents a lower bound...
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justboatonic

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Well sorry not to have posted in here for a little while but I thought I'd let someone take a rest  :}

The first of two posts, the second one is far shorter but just as enlightening.

Anyway, remember I said evidence is growing that our solar system is tending to uniqueness? No!? Then where have you been?

Ever heard of David Latham? No, neither had I! But, it turns out he has been asking the very same question. Well maybe not the very same question but unless you're a pedant, it amounts to the same thing.

"Two decades of searching have failed to turn up another planetary system like ours. Should we be worried?

IT WAS David Latham's misfortune that his email was time-stamped 1 April 1988. An astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, he was engaged in the then faintly disreputable task of searching for planets orbiting other stars. As he excitedly wrote to a colleague, he had found something: a body orbiting an ordinary yellow star, known only by its catalogue designation HD 114762, some 130 light years from Earth.

For Latham's peers, this was nothing more than an April Fool. If the object had been a planet, it would have gone against all we thought we knew about how planets - and indeed solar systems - could look.

Two decades on, planet-hunting is high fashion, and Latham has been vindicated. With hundreds of worlds known and more being discovered every week, planets and solar systems that break the rules are commonplace. In fact, they could well be the rule. It's time to ask the question: is our solar system actually the odd one out?"

and

"In 1995, Michel Mayor and Didier Queloz of the Geneva Observatory in Switzerland discovered a gas-giant planet with a mass similar to Jupiter's in a scorching four-day orbit around the sun-like star 51 Pegasi (Nature, vol 378, p 355). Within a year, Marcy and his colleague Paul Butler, both then at San Francisco State University in California, had confirmed that discovery, and also found two more "hot Jupiters". Later that year, they confirmed Latham's discovery as a planet.

It was clear we had ignored a fundamental rule of science. "We had been judging the cosmic diversity of planetary systems based on a sample size of one," says Marcy."

and there's more!

"If these were the first hints that our solar system was not normal, they were not the last. Other planets were soon caught breaking all sorts of rules: orbiting in the opposite direction to their star's spin, coming packed in close orbits like sardines in a can, or revolving on wildly tilted orbits far away from their star's equator"

"All this makes the status of our solar system increasingly clear. "Our system is a rarity, there's no longer a question about that," says Marcy. "The only question that remains is, just how rare is it?""

Rest of the article http://www.newscientist.com/article/mg21028122.700-no-place-like-home-our-lonesome-solar-system.html? but you'll have to register to read it in full.

Goodness me, what a pleasant surprise to the usual dross of 'we havent search long \ hard \ far enough' of the galaxy yet. But, in a topic some people want to use 'sampling' to both support their argument and knock other down when it suits, it is a valid question. Not only that, but the evidence is imo, pointing towards uniqueness.
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dodgy geezer

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Well sorry not to have posted in here for a little while but I thought I'd let someone take a rest  :}

We're all very thankful for that....


"All this makes the status of our solar system increasingly clear. "Our system is a rarity, there's no longer a question about that," says Marcy. "The only question that remains is, just how rare is it?""

Rest of the article http://www.newscientist.com/article/mg21028122.700-no-place-like-home-our-lonesome-solar-system.html? but you'll have to register to read it in full.

Goodness me, what a pleasant surprise to the usual dross of 'we havent search long \ hard \ far enough' of the galaxy yet. But, in a topic some people want to use 'sampling' to both support their argument and knock other down when it suits, it is a valid question. Not only that, but the evidence is imo, pointing towards uniqueness.



Your original argument was that the Solar System was rare or unique - in particular that Earth-like planets (essentially small, rocky, with liquid water and an atmosphere) would be very rare and hence there was unlikely to be much (or any) possibility of extra-terrestrial life. 

The article you cite certainly includes the words 'our system is a rarity', but goes on to make the following point:
 
"The diversity of these planetary systems tells us that our own is but one example in a very wide range," says Andrew Howard, a planet-hunter at the University of California, Berkeley. But it is not quite time to give up on another solar system that looks like ours, he adds. For Kepler to "find" a planet, that planet must transit across its star three times. Given a planned mission lifetime of three and a half years, Earth would have made the cut - just. But it would take 36 years for Jupiter to make the grade, 90 for Saturn, and even longer for Uranus and Neptune. "If we were looking from outside we still wouldn't have detected most of our solar system," says Howard.

The search for a second Earth

While astronomers seek a planetary system that mimics the architecture of our own, the number of Earth-like worlds is another open question.

In October last year, Andrew Howard and Geoff Marcy of the University of California, Berkeley, released a census of planets orbiting within a quarter of the Earth-sun distance of 150 nearby sun-like stars. A few per cent have close-in planets Jupiter's size or greater, about twice as many have Neptune-mass planets, and at least 12 per cent harbour planets three times Earth's mass, the smallest in the sample. This trend would suggest that one in four sun-like stars have close-in planets Earth's size (Science, vol 330, p 653).

"It tells us that nature makes small planets," says Howard. And while life as we know it would be burned out on these planets, if there are that many planets close in, there are presumably quite a few further out at Earth-like distances.


So it is not the case that the vast majority of all the other systems are definitely 'dead' and ours is likely to be the only one with life. The article makes the point that there is a very wide range of system types (which we didn't expect) and many of them may be capable of supporting life. The Solar System is only 'rare' in the sense that there appear to be many different possible system configurations, of which ours is only one. And the article also points out that the 'sampling' issue is a real and valid reason why "the number of Earth-like worlds is another open question.".

Not only that, but the article also says: "... But it is not quite time to give up on another solar system that looks like ours, he adds. For Kepler to "find" a planet, that planet must transit across its star three times. Given a planned mission lifetime of three and a half years, Earth would have made the cut - just. But it would take 36 years for Jupiter to make the grade..."  That seems to me to be a classic example of "the usual dross of 'we havent search long \ hard \ far enough' of the galaxy yet.", which you seem to think is absent from this paper. I find that when I read your cites they frequently contain statements which say the opposite of what you are suggesting. Don't you read right down to the bottom of them?
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dodgy geezer

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I seem to remember some earlier discussion about tidally-locked planets in the Gleise system, and an assertion made that tidal locking would create extreme variations of climate which would suppress the development of life....

This piece of work may be interesting in that context: http://www2.cnrs.fr/en/1862.htm

It reports a physical model of the expected features of tidally-locked Gleise 581D, which shows "that with a dense carbon dioxide atmosphere - a likely scenario on such a large planet - the climate of Gliese 581d is not only stable against collapse, but warm enough to have oceans, clouds and rainfall.."

The planet is considerably bigger that the Earth, and gets only about 1/7 the sunlight that Earth does, so it would not normally be considered as an Earth-type candidate. But the model suggests that Earth-like temperatures and humidity may still be available. So you do NOT necessarily need an Earth-type planet to harbour Earth-like life conditions. As the conclusion says:

"But the diversity of planetary climates in the galaxy is likely to be far wider than the few examples we are used to from the Solar System. In the long run, the most important implication of these results may be the idea that life-supporting planets do not in fact need to be particularly like the Earth at all. "

So a 'unique Earth' does not necessarily mean a lifeless Galaxy. We are beginning to learn that there are many possibilities out there...  
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justboatonic

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Yes and I seem to remember earlier discussions saying its just a question of time in proving our solar system was the norm. Now, some astronomers are starting to realise that may not be the case.

Pretty much a theoretical paper about Gliese, that one. So, in theory yes, it could be. Likelihood of it being the case, improbable.



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dodgy geezer

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... I seem to remember earlier discussions saying its just a question of time in proving our solar system was the norm. Now, some astronomers are starting to realise that may not be the case...



Looked - couldn't find anywhere that was said. The nearest I could get was this:

Quote
Reply 10

The paper you have cited is in agreement with  Mandell, Raymond and Sigurdsson (2007) ( http://iopscience.iop.org/0004-637X/660/1/823/70644.text.html ) which says:

"If planetary systems that suffer the migration of a gas giant to small distances can eventually form terrestrial planets similar to those in our own system, and the migration of young giant planets is a common result of interactions with the gaseous disk, then it is appropriate to consider the possibility that our own planetary system could have formed earlier generations of giant planets prior to those in the outer solar system.

It is early days yet, as I have often said, but it looks to me as if the migrating hot jupiter theory provides a good explanation of how inner habitable planets can be formed, and may well be the norm for our kind of system....



and I am happy to stand by that suggestion.

We have sent up a probe intended to find planets orbiting nearby stars which are similar to our own. We always knew that we would detect the planets with short orbits first, and we have not yet had the time to detect planets as far out as ours is, so none of the findings will be exactly Earth-like.

What has surprised us is that quite a lot of systems have large planets close to their suns - these seem to have migrated inwards. After a period of consideration, it now seems plausible that this is a common stage in planetary development, and may indeed have happened to our own system in the distant past, as suggested in the paper referenced above. So the systems we have found so far may be well be similar to ours, but at a different stage of development....

We have also found other systems which could have Earth-like planets in them orbiting suns which are not Sun-like. I don't think that anyone has claimed that the Solar System is 'the norm' for systems in the galaxy - for one thing 90% of the stars in the Milky Way are dwarf stars smaller than ours, but the aim of the Kepler probe was to advance our knowledge about Earth-like planets, and it seems to be finding likely candidates quite rapidly, suggesting that there may be quite a few out there...
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justboatonic

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #121 on: June 14, 2011, 08:48:02 PM »

Now the corot missions finds 10 new planets.

But "the latest list of 10 exoplanet finds, seven are so-called "hot Jupiters", gas giant planets similar to our own Jupiter but far closer to their host star - completing their orbits in just days.

Two more orbit the star Corot-24, with diameters equal to and about 1.4 times that of Neptune, completing their orbits in five and 12 days, respectively."

Yet more evidence that our solar system is tending to uniqueness.  >>:-(

oops! Forgot the linky!

http://www.bbc.co.uk/news/science-environment-13761405
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dodgy geezer

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Re: Kepler mission adds more weight to our solar system not being the norm.
« Reply #122 on: June 15, 2011, 12:08:12 AM »


But "the latest list of 10 exoplanet finds, seven are so-called "hot Jupiters", gas giant planets similar to our own Jupiter but far closer to their host star - completing their orbits in just days.

Yet more evidence that our solar system is tending to uniqueness.  >>:-(



Yaaawn! How many times do we have to tell you that these probes will ALWAYS find the large close planets FIRST? The fact that they are finding them proves nothing about other systems which may be similar to ours, and so do not have large planets close to their sun, which will therefore not be so easily detected.

Incidentally, we only seem to hear from you when the mass media put out a story. There is a lot of extra-solar planetary work going on at the moment, much of it tending to show that non-terrestrial life is quite likely to be found. And yet we do not hear anything from you about this. You seem to be only choosing papers which fit your (mistaken) world view.

For example, take the classic belief that having a large close-coupled Moon is essential for the development of life on this planet. It tends to protect us from meteorite bombardment, and gives us the tides, which are often seen as critically important in bio-development. It also holds us level in the axial plane and minimises gravitational disturbance from other planets. The Earth-Moon system is almost a double planet, and the only other comparable pair in the Solar System is Pluto/Charon, so getting one in the habitable zone was thought to be quite rare, and often cited by rare-earth enthusiasts as another reason for believing that our system 'tended to uniqueness', and was the only one where life had developed as a result.

Here are two papers released over the last month, both addressing the 'rare moon' issue. One suggests that 'double-planet' moon systems may actually be ten times as common as was thought, while the other suggests that it may not matter anyway, as the stability influence that a big Moon provides is less important than was thought.

http://www.slideshare.net/sacani/how-common-are-earth-moon-planetary-systems

http://news.sciencemag.org/sciencenow/2011/05/who-needs-a-moon.html?ref=hp

If I wanted to it would be easy to inundate this thread with examples of research tending to show that Earth-like systems are likely to be quite common in the Galaxy, and that the conditions for life that we would recognise are likely to occur on many of these, as well as many other system which are not like ours, but could still harbour life. I can't see why I should, particularly on a model boat board....



 
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