i read this at a site taht says these are what is need for life to exist. check it out

Parameter Probability that feature will fall in the required range

galaxy size .1

galaxy type .1

galaxy location .1

star location relative to galactic center .2

star distance from closest spiral arm .1

z-axis extremes of star's orbit .1

proximity of solar nebula to a supernova eruption .01

timing of solar nebula formation relative to supernova eruption .01

number of stars in system .2

star birth date .2

star age .4

star metallicity .05

star orbital eccentricity .1

star's distance from galactic plane .1

star mass .001

star luminosity relative to speciation .0001

star color .4

3H+ production .1

supernovae rates and locations .01

white dwarf binary types, rates, and locations .01

planetary distance from star .001

inclination of planetary orbit .5

planetary axis tilt .3

rate of change of axial tilt .01

planetary rotation period .1

rate of change in planetary rotation period .05

planetary orbit eccentricity .3

surface gravity (escape velocity) .001

tidal force .1

magnetic field .01

albedo .1

density .1

planetary crust thickness .01

oceans-to-continents ratio .2

rate of change in oceans-to-continents ratio .1

global distribution of continents .3

frequency and extent of ice ages .1

asteroid and comet collision rate .1

change in asteroid and comet collision rates .1

mass of body colliding with primordial Earth .002

timing of collision with primordial Earth .05

rate of change in asteroid/comet collision rate .1

proximity and mass of Jupiter .01

major planet eccentricities .1

major planet orbital instabilities .1

drift rate and rate change of major planets .1

atmospheric transparency .01

atmospheric pressure .1

atmospheric electric discharge rate .1

atmospheric temperature gradient .01

carbon dioxide level in atmosphere .01

oxygen level in atmosphere .01

chlorine level in atmosphere .1

iron quantity in oceans .1

tropospheric ozone quantity .01

stratospheric ozone quantity .01

mesospheric ozone quantity .01

water vapor level in atmosphere .01

oxygen-to-nitrogen ratio in atmosphere .1

quantity of greenhouse gases in atmosphere .01

frequency and extent of forest and grass fires .01

soil mineralization .1

quantity of sea-salt aerosols .1

quantity of decomposer bacteria in soil .01

quantity of mycorrhizal fungi in soil .01

quantity of nitrifying microbes in soil .01

quantity of sulfur in soil .1

quantity of sulfur in planet's core .1

tectonic activity .1

volcanic activity .1

decline in volcanic activity .1

viscosity of Earth's core at core boundaries .01

biomass to comet-infall ratio .01

regularity of cometary infall .1

dependency factors (estimate) 100,000,000,000

longevity requirements (estimate) .00001


Probability for combined occurrence of all 75 parameters = 10-99

if thats true, then thats really interesting
do u have a link to that site at all?

godandscience.com

sweet, thx

edit - although i think its '.org' at the end

waht does everyone else think about the data?

well i guess the criteria i provided kindas points toward we are alone.

When I first started reading this I thought it was like the Drake Equation. In case nobody heard of it...

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

Not true...

See we look at life as having to exist with a nitrogen/oxygen atmosphere as one of the points made above. The thing is though other life could be so different from us they may be incomprhensable to our current sciences. They m,ay not need air to breathe or eyes to see etc.

Just because our life evolved on earth doesn't mean that life will have to evolve on planets similar. Givin however it is the only life we know it is why we search for criterias that made life on earth possible. I think once we start exploring the galaxy life won't be abundant however i think has to exist elseware besides us. Earth should be viewed as proof of life elseware simply because we exist.

Some of those don't make sense...


The Sun is 1 solar mass.

Those numbers mean nothing...It's a good try, but some of them make no sense....

tidal force=.1 WTF?

The probability of there being life in the universe is nearly 100%. Dr. Amir D. Aczel author of Probability 1: Why there must be Intelligent Life in the Universe is Associate Professor of Mathematical Sciences at Bentley College. His work has been translated into French, German, Italian, Spanish, Dutch, Swedish, Finnish, Norwegian, Polish, Greek, Chinese and Japanese.

The Drake equation is obsolete in comparison with Dr. Amir D. Aczel's calculations.

The Drake equation states that: N = R* x fp x ne x fl x fi x fc x L

where:
N is the number of civilizations in our galaxy with which we might expect to be able to communicate at any given time
and

R* is the rate of star formation in our galaxy
fp is the fraction of those stars that have planets
ne is average number of planets that can potentially support life per star that has planets
fl is the fraction of the above that actually go on to develop life
fi is the fraction of the above that actually go on to develop intelligent life
fc is the fraction of the above that are willing and able to communicate
L is the expected lifetime of such a civilization

According to Drake's estimated calculations N=10,000. In other words there are 10,000 communicative civilizations in the Milky Way Galaxy.

Probability 1 goes far beyond what was explored with the Drake equation. Drake's equation refers only to our galaxy, whereas Dr. Amir Aczel's calculations refer to the universe as a whole.

P (life on at least one planet outside the earth) = 1 - (0.99999999999995) ^30,000,000,000,000,000,000,000,000 = a number indistinguishable from 1.

1=100% probability that advanced extraterrestrial civilizations exist elsewhere.

all these factors happening are remote. but most scientists believe life exists out there

Did you not read my post or am I just reading this wrong? The possibility of all the vital factors of planet formation and life coming together is by no means remote when taking into consideration the size of our galaxy let alone the universe.

With the age of our galaxy, the age of many of these civilizations is undoubtedly great. So, with that we can safely conclude, with a few billion years more knowledge than us, they would undoubtedly be capable of interstellar travel at the instantaneous level. If this is a capability of an extraterrestrial civilization in our galaxy then it wouldn't take very long to survey every star system in the entire galaxy. Of course, this would take a great deal of time but could be completed within a few thousand years at the most. Our galaxy is consideribly old in comparison with other galaxies in the universe so it is very likely that we are the new kids on the block available for study, surveillence, and guidance when needed. Our galaxy has nearly used up most of its available star dust as compared to other galaxies that appear to be very murky in appearence by the abundance of star dust present that has yet to condense to form habitable star systems. The average age of the stars within the galactic habitable zone of our galaxy, which the earth also resides, is about 10,000,000,000 years older than our sun! Suggesting the very high likelyhood of civilizations extremely advanced far beyond our own. Just imagine the possibilities of a civilization in which has had even a fraction of that time to evolve! The earth is extremely young by the galactic standards of our galaxy. Therfor, one cannot discount the very likely and probable possibility that earth is indeed being visited and studied by civilizations far in advance of our own.

Regardless of what you truly meant by this statement, here is an article you may find interesting, JBIS Article "Inflation-Theory Implications for Extraterrestrial Visitation": http://www.ufoskeptic.org/JBIS.pdf

Article regarding the JBIS article,

By Leonard David Senior Space Writer states,
”Decades ago, it was physicist Enrico Fermi who pondered the issue of extraterrestrial civilizations with fellow theorists over lunch, generating the famous quip: "Where are they?" Now a team of American scientists note that recent astrophysical discoveries suggest that we should find ourselves in the midst of one or more extraterrestrial civilizations. Moreover, they argue it is a mistake to reject all UFO reports since some evidence for the theoretically-predicted extraterrestrial visitors might just be found there. The researchers make their proposal in the January/February 2005 issue of the Journal of the British Interplanetary Society (JBIS).

Pick up any good science magazine and you’re sure to see the latest in head-scratching ideas about superstring theory, wormholes, or the stretching of spacetime itself. Meanwhile, extrasolar planetary detection is on the verge of becoming mundane. "We are in the curious situation today that our best modern physics and astrophysics theories predict that we should be experiencing extraterrestrial visitation, yet any possible evidence of such lurking in the UFO phenomenon is scoffed at within our scientific community," contends astrophysicist Bernard Haisch, along with physicists James Deardorff, Bruce Maccabee and Harold Puthoff make their case in the JBIS article: "Inflation-Theory Implications for Extraterrestrial Visitation".

The scientists point to two key discoveries made by Australian astronomers and reported last year that there is a "galactic habitable zone" in our Milky Way Galaxy. And more importantly that Earth’s own star, the Sun, is relatively young in comparison to the average star in this zone -- by as much as a billion years. Therefore, the researchers explain in their JBIS article that an average alien civilization would be far more advanced and have long since discovered Earth. Additionally, other research work on the supposition underlying the Big Bang -- known as the theory of inflation -- shores up the prospect, they advise, that our world is immersed in a much larger extraterrestrial civilization.

Point-to-point distances

Given billion-year advanced physics, might not buzzing around the galaxy be possible? Even today superstring theory hypothesizes other dimensions... which could be habitable Universes adjacent to our own, the researchers speculate. It might even be possible to get around the speed of light limit by moving in and out of these dimensions. "What we have done is somewhat of a breakthrough," Haisch told SPACE.com. "We have pulled together various recent discoveries and theoretical issues that collectively point to the strong probability that we should be in the midst of one or more huge extraterrestrial civilizations," he said. Haisch said that superstring dimensions and wormhole and spacetime stretching possibilities address the "can’t get here from there" objection often argued in view of the interstellar, point-to-point distances involved. Also, diffusion models predict that even a single civilization could spread across the Galaxy in a tiny fraction of the age of the Galaxy - even at sub-light speeds, he said.

ET signature in the data

Can the scientific community bring itself to consider any evidence coming from mysterious sightings of strange things by the public? In large measure, the scientific community seemingly has eyed ET visitation as far from being serious stuff to cogitate over. Why so? "The dismissal has several causes, all reinforcing each other," Haisch responded. "Most of the observations are probably misinterpretations, delusions and hoaxes. I have seen people get confused by Venus or even Sirius when it is flashing colors low in the sky under the right conditions. Having been turned off by this, most scientists never bother to look any further, and so are simply blissfully ignorant that there may be more to it," he said. Deardorff, the lead author of the JBIS article, points out in a press statement: "It would take some humility for the scientific community to suspend its judgment and take at least some of the high quality reports seriously enough to investigate…but I hope we can bring ourselves to do that."

According to Haisch, there is a motivation not just for scientific tolerance of the UFO issue, but a strong scientific prediction that there ought to be some genuine ET signature in the data. "This potentially changes the relationship of the UFO phenomenon to science in a significant way. It takes away the ‘not invented here’ prejudice, pointing out that a ‘yes’ to ET visitation is exactly what side our current physics and astrophysics theories would come down on as the most likely situation," Haisch concluded. Thanks to Harold Puthoff and Leonard David Senior Space Writer.

the universe is a very big place, but some of it is unhabitable, sorry to say. only 10 percent of stars in the galaxy are habitable.

Even with this estimation, there are somewhere between 200 and 600 BILLION stars in the Milky Way. We will estimate the total to be around 400 billion.

You said that only 10% of stars in the galaxy are habitable. Well, 10% of 400,000,000,000 is 40,000,000,000 stars in the galaxy capable of harboring life, according to your estimations that is. So where is this doubt coming from? You obviously haven't thought this though very thoroughly.

In 1999 the Hubble Space Telescope estimated that there were 125,000,000,000 galaxies in the universe. So from what you are saying 40,000,000,000 per galaxy multiplied by 125,000,000,000 galaxies equals 5,000,000,000,000,000,000,000 stars in the universe capable of harboring life and each and every one of these stars is capable of harboring life on multiple planets within its solar system.

Your own estimations contradict your opinion.

The Hubble telescope cannot estimate Nasa can

I've done an exercise using such numbers, and it is not hard to see that statistically, things can look fairly impressive. And, I lean in that direction.

One thing I have noticed is the compostition of these "murky" galaxies is still not clear.
Even the best ideas are challenged by newer ones, and familiar ideas are replaced by others and the whole business continues pushing the limits with today's telescopes, etc.

Bottom line, some ideas sound great, like A+B=~ C, and I greatly hold that we are not special, but I also recognize that it takes some imagination to consider the possibilities.

Good posts in this topic.

Oh, one last thing. What if some species made the leap, to advanced travel in spacetime.
And what if the "medium is the message"? That is, if the medium is a passage to other dimensions (yes, I know...), and if that is a passage to other worlds, beyond- what's to keep them here? Maybe that is why we don't "get the message". They guard the passage as if they owned it!

Maybe it is what heaven is- some place where advanced races end up.

Enough sci-fi for tonight.

even though i wanna believe in other life, the factors point towards that the earth is special. sorry to admit it

There is life elsewhere and that's a fact. Even if only 1% of stars in the universe were capable of harboring life this would mean that 4,000,000,000 stars in our galaxy are capable of harboring life and an estimated 500,000,000,000,000,000,000 stars in the universe capable of harboring life. And remember each of these stars is capable of harboring life on more than one planet. Sorry, but the facts are heavily against you.

the 75 factors that u need for complex life are unlikely to happen again. so we may be alone. i would want to be proved wrong

The information you provided is both misleading and inaccurate -- and that's a fact. They are based soley on conjecture. The information provided is hardly scientific. It is but one scientists opinion on what circumstances are manditory for intelligent life to exist and prosper. It's funny that you believe this isolated opinion over all the scientific data and sources that I have provided you with to the contrary. This was actually a common concensus belief a few years ago in the scientific community. However, as you can see the consensus has now changed entirely. Almost all scientists are now at a consensus that life definatly exists elsewhere and is fairly abundant throughout the universe.

i feel scared after i learned that earth is a cosmic fluke. i think its discouraging. dont get me wrong, i believe life exists, but site after site, i read the possibility of life arising twice is liek 1 in 10 to the 282 power

Well then you should check your sources because they obviously don't know what they are talking about. They are referring to arguments made and agreed upon years ago before intelligent life or any kind of life for that matter was believed to be possible. In recent years science has proven otherwise.

"It has recently been argued that anthropic reasoning applied to inflation theory reinforces the prediction that we should find ourselves part of a large, galaxy sized civilisation, thus strengthening Fermi's paradox concerning "where are they?" Furthermore, superstring and M-brane theory allow for the possibility of parrallel universes, some of which in principle could be habitable. In addition, discussion of such exotic transport concepts as "traversible wormholes" now appears in the rigorous physics literature. As a result, the "We are alone" solution to Fermi's paradox, based on the constraints of earlier 20th century viewpoints, appears today to be inconsistent with new developments in our best current physics and astrophysics theories. Therefore we reexamine and reevaluate the present assumption that extraterrestrials or their probes are not in the vicinity of Earth, and argue instead that some evidence of their presence might be found in certain high quality UFO reports. This study follows up on previous arguments that (1) interstellar travel for advanced civilizations is not a priori ruled out by physical principles and therefore may be practicable, and (2) such advanced civilisations may value the search for knowledge from uncontaminated species more than direct, interspecies communication, thereby accounting for aparent covertness regarding their presence."

Source of quote: http://www.ufoskeptic.org/JBIS.pdf

"This question is no longer a matter of idle speculation."

"Although it is impossible to predict the precise features of such advanced civilizations, their broad outlines can be analyzed using the laws of physics. No matter how many millions of years separate us from them, they still must obey the iron laws of physics, which are now advanced enough to explain everything from sub-atomic particles to the large-scale structure of the universe, through a staggering 43 orders of magnitude."

Source of quotes: http://www.mkaku.org/article_physicsofextra.htm

We still cant say what real aliens are like, of course, but science can provide some useful insights. After all, any biology out there will exist in a landscape of finite resources.

So how can we judge whether life is a likely evolutionary development or not? We do the obvious, and look for hints in Earths history. Earth is, after all, the only example we have. Since high IQ critters appeared here, theres a tendency to assume that our planet is just another typical, run-of-the-mill rocky world, and what happened on our planet might happen on their planet, too. Sooner or later, intelligence will arise.

But there are flies in this ointment. Sixty-five million years ago, a rock the size of Brooklyn slammed into the Earth, wiping out three-fourths of all species, including the dinosaurs. If this hadnt happened, the rat-like mammals that eventually evolved into Homo sapiens wouldnt have inherited the world. And 245 million years ago, another catastrophe (known in polite society as the Permian extinction) wrote finis to an even larger percentage of species. These cosmic accidents were all forks in the long road that eventually led to us. Maybe on other worlds, the road never gets that far.

Extremophiles are the exception, rather than the rule. And yet when we search the solar system for biology, we expect that if there are alien life-forms nearby, they will most likely be analogs to Earth’s extremophiles. This is simply because, whether you’re talking about aquifers beneath the cold, ultraviolet-stung sands of Mars, or the deep, salty seas of Europa, you’re describing environments as brutal as Green Bay’s defensive line. Most of your local flora and fauna would perish straight-away in these nasty niches. But Earth’s extremophiles – some of them – could be transplanted to such otherworldly habitats and never look back.

but the factors must be met at 1 time and 1 place. go ahead, tell me some of the factors u dont need for life that i listed

Makaya, the factos you posted make no sense...The Sun breaks many of those 'rules for life'.

these factors do oppose the possibility of life existing. no one has told me factors that i listed that u dont need for life. so as of now, odds of life is remote