The statitistics
1) The number of galaxies. An estimated 50 billion galaxies are visible with modern telescopes and the total number in the universe must surely exceed this number by a huge factor, but we will be conservative and simply double it. That's 100,000,000,000 galaxies in the universe.
2) The number of stars in an average galaxy. As many as hundreds of billions in each galaxy.
Lets call it just 100 billion.
That's 100,000,000,000 stars per galaxy.
3)The number of stars in the universe.
So the total number of stars in the universe is roughly 100 billion x 100 billion.
That's 10,000,000,000,000,000,000,000 stars, 10 thousand, billion, billion. Properly known as 10 sextillion. And that's a very conservative estimate.
4) The number of stars that have planetary systems. The original extra-solar system planet hunting technology dictated that a star needed to be to close to us for a planet to be detected, usually by the stars 'wobble'. Better technology that allows us to measure the dimming of a stars brightness when a planet crosses its disk has now revolutionised planet hunting and new planets are being discovered at an ever increasing rate. So far (August 2003) around 100 have been discovered so we have very little data to work on for this estimate. Even so, most cosmologists believe that planetary formation around a star is quite common place. For the sake of argument let us say it's not and rate it at only one in a million and only one planet in each system, as we want a conservative estimate, not an exaggerated one. That calculation results in:
10,000,000,000,000,000 planets in the universe. Ten million, billion, as a conservative estimate.
5) The number planets capable of supporting life. Let's assume that this is very rare among planets and rate it at only one in a million. Simple division results in:
10,000,000,000 planets in the universe capable of producing life. Ten billion!
Simple division results in:
10,000,000,000 planets in the universe capable of producing life. Ten billion!
Ten billion worlds out there, billions of dollars being spent, Amount we have found 0 seems like a lot less then 10,000,000,00 seems more closer to 0 to me.
Until we find one, I think we might have just as much chance as finding a real live big-foot than life out there, the evidence for both is about the same
Simple division results in:
10,000,000,000 planets in the universe capable of producing life. Ten billion!
Ten billion worlds out there, billions of dollars being spent, Amount we have found 0 seems like a lot less then 10,000,000,00 seems more closer to 0 to me.
Until we find one, I think we might have just as much chance as finding a real live big-foot than life out there, the evidence for both is about the same
The statitistics
1) ... That's 100,000,000,000 galaxies in the universe ...
... 10,000,000,000 planets in the universe capable of producing life. Ten billion!
I am really enjoying this discussion
GREAT STATISTICS WELL SAID, I LOVE IT, course there's something out there, and if not just watch Stargate and dream.
I'm enjoying it too -- you have already arrived at a conclusion that is a more conservative estimate than my own -- by one or two orders of magnitude in fact. My estimate was between 1 and 10 civilisations in our Milky Way galaxy with one being more likely.
Your figures conclude
100 billion galaxies that include 10 billion civilisations ... that's one civilisation per ten galaxies -- or 0.1 civilisations per galaxy.
Very much in line with my conclusion thank you !
To take it further, if we read your words exactly your conclusion is: "10 billion with life", of which 1 in 10 would have multicellular life, of which maybe 1 in 100 would have plants and animals of which maybe 1 in 100,000 would develop intelligence, of which maybe 1/100 would become space-faring races.
This leaves us with one space faring race in the Universe. We are already a space faring race.
Nor is there enough data for some to say that life doesn't exist and that we are the only ones.
Yep .. I agree with that.
Quote:
Originally Posted by supernova
But statistical records show that if something has happened once it is more likely to happen again and that the more chances it has to happen again "ie" more stars and therefore more planets the more likely it is to happen.
Could you perhaps point me to where I might be able to find a peer-reviewed scientific paper which demonstrates the logic supporting this statement ?
Quote:
Originally Posted by supernova
I think that we consider that other planets must be like Earth to evolve life but NASA's announcement shows that the old thoughts on what is needed for life has to be changed and new possibilities considered.
Yep. New thoughts about where to look for our version of it .. nothing else.
Quote:
Originally Posted by supernova
The statistics ….
10,000,000,000 planets in the universe capable of producing life. Ten billion!
Yep .. amazing isn’t it ?
We might be the 1 in ten billion chance occurrence, too !
.. or, we might not be !
And until another instance is found, these are the only rational statements we can make. Any other 'statistical' ones, are purely conjecture.
Quote:
Originally Posted by Supernova
I am really enjoying this discussion
No worries Warren .. we both know no-one's going to get to be right here, eh ?
I am not sure what the purpose of the press release from NASA was intended to do. It's tantalising wording has caused speculation from discovery of microbes on Mars to an alien airport at Area 51 to invasion by a warlike extragalactic race.
The whole upshot is NASA rehashes some work done and published at least 2 years ago (obviously more work done since then, probably confirmation of results at teh very least). The hornets nest is stirred, and many people are putting forward their hard held beliefs as ultimate truths (pardon me while I go rustle up some stakes and matches). The scientist will say "It cannot be with out proof"... The Believer's gut feeling says "It must exist elsewhere". Without the scientific method we cannot advance because if we do not underpin our knowledge with proof and prediction we walk on thin ice and go crashing through.
To believe without proof and use the obvious "facts" as basis of world/universal view leads to the perception that any disagreement is heretical (I've got the matches here if you need them).
Personally I have trouble believing that the universe conspired to create one oand only one cradle of life, but that is a gut belief on my part. I have no evidence of this as I have only a sample of one, but I look in the sky (well not lately with La Nina), it seems that the odds are too small for no other life. However the scientist cannot say that it doesn't/cannot exist... no data.
I'm not sure that we will ever know, but this discussion was about the NASA press release. The question remains: Why announce old news in this manner? It can only harm their reputation and creditability, IMHO.
So... to recap, I am with Warren in that it "seems to be an awful waste of space" (thanks Eric), but I can see where Craig is coming from and the scientific method. Hows that for fence sitting?
PS thare has been some creative maths in this thread
I am not sure what the purpose of the press release from NASA was intended to do. It's tantalising wording has caused speculation from discovery of microbes on Mars to an alien airport at Area 51 to invasion by a warlike extragalactic race.
The whole upshot is NASA rehashes some work done and published at least 2 years ago (obviously more work done since then, probably confirmation of results at teh very least). The hornets nest is stirred, and many people are putting forward their hard held beliefs as ultimate truths (pardon me while I go rustle up some stakes and matches). The scientist will say "It cannot be with out proof"... The Believer's gut feeling says "It must exist elsewhere". Without the scientific method we cannot advance because if we do not underpin our knowledge with proof and prediction we walk on thin ice and go crashing through.
To believe without proof and use the obvious "facts" as basis of world/universal view leads to the perception that any disagreement is heretical (I've got the matches here if you need them).
Personally I have trouble believing that the universe conspired to create one oand only one cradle of life, but that is a gut belief on my part. I have no evidence of this as I have only a sample of one, but I look in the sky (well not lately with La Nina), it seems that the odds are too small for no other life. However the scientist cannot say that it doesn't/cannot exist... no data.
I'm not sure that we will ever know, but this discussion was about the NASA press release. The question remains: Why announce old news in this manner? It can only harm their reputation and creditability, IMHO.
So... to recap, I am with Warren in that it "seems to be an awful waste of space" (thanks Eric), but I can see where Craig is coming from and the scientific method. Hows that for fence sitting?
PS thare has been some creative maths in this thread
On Exo-life possibilities:
Yeah Tony .. cool words .. good onya .
Its Ok to have an opinion …. mine is that I wouldn't have the foggiest … and neither does anyone else .. so don't go using statistics or science as a 'front' for what is purely a belief (or gut-feel).
On the press release:
IMHO its done to guide researchers and give them some support in their next bid for funding. Ie: its a hint of 'Strategic Guidelines' for justifying future bid proposals and to give some foundations for where to go looking for exo-life, in future space exploration … nothing more.
One thing extra one can say .. if we don't go looking for exo-life .. we won't find it and thus, this gives credence to the 'it doesn't exist' argument.
To take it further, if we read your words exactly your conclusion is: "10 billion with life", of which 1 in 10 would have multicellular life, of which maybe 1 in 100 would have plants and animals of which maybe 1 in 100,000 would develop intelligence, of which maybe 1/100 would become space-faring races.
This leaves us with one space faring race in the Universe. We are already a space faring race.
Natural conclusion is ...
It's worse than that, as from actual experience here on Earth, the ratio of human-level intelligent species to the rest of the plants and animals is at best around 1 in 10,000,000 = 100 times fewer than 1 in 100,000.
I am not sure what the purpose of the press release from NASA was intended to do. It's tantalising wording has caused speculation from discovery of microbes on Mars to an alien airport at Area 51to invasion by a warlike extragalactic race.
Well to divert back somewhat to topic, the answer I think is reasonably obvious. NASA and all their programmes are almost entirely dependent upon the public purse. In order to gain public support for all the programmes they run (remembering it's the public who vote) they have to gain popular media exposure.
Now if NASA puts out a bland press release to the effect that they'd discovered some microbe that thrives in an arsenic laden environment, that story will promptly end up on the spike and in all likelyhood few (if any) popular media reps will attend a press-conference and it will all pass under the radar. Most of us here appreciate that this finding is a moderately interesting if not moderately important story. The popular media and the public at large won't or don't -- so it won't be reported. The extent of science literacy in the mainstream media is appalling.
However, NASA know as well as anyone that over the last 70-odd years, nearly all of us have become conditioned to believe that E.T is out there, E.T is good, we must make contact with E.T etc etc. Not for one single solitary moment am I accusing anyone of being in an unlawful or immoral conspiracy -- it is just a natural result of the media and entertainment industry and the ideal being sold to us. They're (the media and enterntainment industry) not doing an evil thing in doing this -- all they are setting out to do is make a buck (Star Trek, E.T, X-Files, Area 51 etc etc). Its a good story, its a popular story, there's a buck to be made out of it -- push it while it's turning over a dollar.
Most people, purely as a result of popular culture (and without any empirical evidence) want to believe. They are eager for news that science fiction in this regard is become science fact.
The practical upshot of this is that NASA can gain exposure and wide public support by being seen to pursue the quest for finding E.T -- because everyone wants that question answered and a large majority want it answered in the affirmative (rightly or wrongly).
To then do it the way they do it gains them media attention, which in turn enhances public support (people now know NASA is actively pursuing the E.T question), which ensures the money (from government) keeps flowing into all their programmes.
In the end it's just sensible P.R. I reckon.
The popular media (by and large) loves it too. For two days speculation has run rife all over the world. Speculation about exceptional news makes headlines that sells copy and boosts circulation/ratings. Hot copy generates advertising revenue. Advertising revenue boosts the bottom line -- get it!
If instead NASA had gone the conservative route, the story would probably have been immediately spiked in favour of a "Man bites dog" expose or a story about how some revolutionary new herbal tea makes your bottom look smaller or what Paris Hilton is up to with that fellow in the dark glasses. NASA gets no exposure. Their public profile drops, their relevance to the voter drops and then ultimately, their budget drops when the time comes to slice-up the pie. Feed that on ... what then happens to the grants that several members of this forum (Anthony & Trevor + ors) are in receipt of to carry on important work when NASA's budget is cut ??
Some people I think may be a bit arrogant to think that intelligent life is unique in this galaxy let alone in the universe, personally I think life it's rampant throughout but maybe not life as we know it Jimmy
Some people I think may be a bit arrogant to think that intelligent life is unique in this galaxy let alone in the universe, personally I think life it's rampant throughout but maybe not life as we know it Jimmy
But where is the proof that there is all this extra life? the proof so far is nil all we have is a maths equation that points to the probability of it being a fact, not proof it is a fact. You could probably have a probability equation to say anything is probable, even walking through a wall. just because there is life here doesn't prove there is life anywhere else, Just because there is a elephant in the zoo doesn't prove there is one is my house, there probably may be one there or probably not, but not the proof.
The NASA announcement is good because its making people think outside the standard world view of what we think life might be like. Just like the TED video I put up, It points to new views on how we view life, not just with a earth only view of universe,
Last edited by joe_smith; 04-12-2010 at 01:08 AM.
Reason: spelling - hard night a work lol
Hmm .. the recent Cassini discovery of free oxygen in the atmosphere of Rhea would add a data point of disproof to this one, it being thought to have been created by radiolysis.
Cheers
PS: Remote observations of Europa and Ganymede also show atmospheric oxygen.
I think you missed his point Craig. He wasn't making a statement as to the origins of Oxygen, just it's use by lifeforms
Could you perhaps point me to where I might be able to find a peer-reviewed scientific paper which demonstrates the logic supporting this statement ?
This is basic statistics/logic, it doesn't require a peer reviewed scientific paper! If humans commit murder, the more humans there are the more murders are committed. Yes there are other factors than just numbers of humans but statistics/observation shows this logic to be true. Is there any reason such logic cannot be applied here?
But where is the proof that there is all this extra life? the proof so far is nil all we have is a maths equation that points to the probability of it being a fact, not proof it is a fact. You could probably have a probability equation to say anything is probable, even walking through a wall. just because there is life here doesn't prove there is life anywhere else, Just because there is a elephant in the zoo doesn't prove there is one is my house, there probably may be one there or probably not, but not the proof.
The NASA announcement is good because its making people think outside the standard world view of what we think life might be like. Just like the TED video I put up, It points to new views on how we view life, not just with a earth only view of universe,
I am sorry but I have to answer your question with another one where is your proof that it doesn't exist at least there is a scientific mathematical equation that points to the probability of it being a fact. I have yet to see any shred of evidence mathematical or another type (correct me if I am wrong by providing such) but sofar in this discussion I have seen pleanty of circumstantial evidence for life existing out there but absolutely none to show that it doesn't exist. A maths equation is not nil it is scientific and has been used to prove countless things in the past all of the things we take for granted like the computers and internet we are having this discussion on are the result of mathematics.
There may not be an Elephant in your house have you checked your fridge lately I have heard that they tend to be where the Peanut Butter is check it for footprints it doesn't mean that there are none it just means they are not in your house but they are in India and Africa.
To digress a little. Seems that NASA shot itself in the foot again. Big hoo-hah, little result - for a SPACE agency. Its a huge deal for biologists, probably worth some kind of prize, but NASA claiming credit when all they did was pony-up the readies sort of back-fires. I suspect JQ Public was expecting something on the order of "ET is a virus!" or "Bugs on Mars!", and what we got was old news about another extremeophile.
NASA really needs to re-think its PR.
To digress a little. Seems that NASA shot itself in the foot again. Big hoo-hah, little result NASA really needs to re-think its PR.
too right, its dullsville, NASA = Space to nearly everyone on the planet, all that fuss for nothing space related.... they should be feeling very emabarrassed
seems like a lot less then 10,000,000,00 seems more closer to 0 to me.
now find real life out there and win a Nobel prize
