http://www.completetranslations.com/...opic.php?t=296 (mirror)

Why We Are, For All Practical Purposes, Alone in the Universe:

1. It doesn't matter that there are billions of galaxies with billions of stars. The distance between galaxies is so staggering that any civilization in another galaxy would have changed or died during the time it would take to communicate to another galaxy.

2. Things are not as they appear. And reality is not as hopeful as scientists who are looking for ET suggest. Technology has given us the ability to look for extra-solar planets. But scientists fail to mention that they are focusing their attention on star systems that are not binary. You see, eventhough there are billions of stars in our galaxy, you can take more than 2/3rds of those stars and disgard them in a search for ET because they are binary stars. http://imagine.gsfc.nasa.gov/docs/as...s/980402c.html

3. Even if Life is abundant in the Galaxy, plant and animal life is rare. Take our planet as an example:
http://www.ucmp.berkeley.edu/alllife/threedomains.html
Plus, it took a long long long long long time for plant and animal life to come about:
http://ares.jsc.nasa.gov/astrobiolog.../timeline2.htm. Also notice that plant and animal life occurred after a series of unlikely events. And, on top of all this, human life and other intelligent life is even rarer. Even if you take Earth as a model of a planet that exists throughout the galaxy we are still most likely alone.

4. Liquid water is rarer than you might think. Scientists that are hopeful that we are not alone in the galaxy often mention that all is needed is the existance of liquid water. It is a very common mistake that temperature is the only factor in keeping water in a liquid state. This is not true. Liquid water is rare because it requires a combination of temperature and pressure. Liquid water "boils" at room temperature in a vaccume.

By the way, it is the lack of atmospheric pressure on Mars (1% of that on Earth) that is the reason why liquid water does not exist there today.

5. Geologists think that our sort of Earth/Moon arrangement is important for the existance of the kind of life we have: http://www.spacedaily.com/news/life-01x1.html. So the question arises, how probable is it that a small, rocky planet could have a planetoid moon of our size. According to the BBC special "The Planets" it is very improbable. Part of the mission of the Apollo project was to determine the origin of our moon. Because of the age and compisition of the rocks on the moon it was eventually determined that the moon was born from a collision of another smaller planet into the Earth. Somehow the Earth survived and the upheaval of debris formed the moon. It is not very likely that our Earth/Moon arrangement is common.

6. The fact that we are alone is proved by Enrico Fermi's paradox: http://zebu.uoregon.edu/~js/cosmo/lectures/lec28.html. Scientists whose employment at NASA and other simular organizations depend on their ability to find reasons to disagree with Fermi cannot say that somehow they know better: http://www.nobel.se/physics/laureate...fermi-bio.html.

http://www.ufoevidence.org/documents/doc92.htm

But what makes Fermi's paradox have even more weight is the fact of just how late a bloomer our solar system really is. According to the BBC's program "The Planets", the galaxy was around for tens of billions of years before ejected debris from an exploded star coalesced into what is now our solar system. If life had been and is a common thing, star systems would be thriving with life by now.

7. Evolution does not favor intelligence. Evolution favors power and stength over intelligence. Dolphins and The Great Apes are flukes that evolved their intelligence due to the fact Nature did not provide their bodies with the capacity to be natural killers. We don't have fangs or razor sharp claws and neither do dolphins. Intelligence had to evolve in these species because, with humans, they had to compete with 4 legged preditors and, with dolphins, they had to outwit sharks.

8. The life of a star is not long enough. Once again I site the BBC's program "The Planets" as a reference. The Earth has existed for about 4 billion years. Human beings have been around for probably less than one million years. But what makes the scenerio unpromising for ETI to evolve is the fact that today, right now, the Earth is middle aged. The Earth is middle aged because our sun is middle aged. We have passed the half-way point of the sun's life. By appearances, we are lucky to have popped into existance at all. I wonder how may star systems evolve life only to have it snuffed out while only the most primitive of mammals -- if that -- roam about.

Clearly the best evidence for other advanced life being too rare and/or too far away is the fact we haven't heard from them yet.

But, I hesitate to make all those other assumptions about no liquid water and this kind of solar system vs that kind of solar system because we have only seen a sample size of one solar system. Only recently have we started to obtain data on other solar systems.

And, the rate of advance of our scientific discoveries and technologies has been logarithmic. So who's to say in the future we won't find animals or at least evidence of animal life in nearby solar systems?

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Does it really matter? Face it, we are alone! I don't wonder why we can't lick our butt. Do you?

I think you've been up a bit too long dear. Perhaps you should get to bed. :-? :P

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Democracy Now! - The lost art of investigative news reporting.

Sorry. I just don't understand why "we" don't understand why "we" are alone in this big old universe. "We" are special! "We" are a freak of nature! There are no others out there, no matter what the woo woo's think. Why do "we" think there has to be just cause for existance? Best just to understand the now and live with it. Enjoy today! I do.

What I dislike about 'we are alone in the universe' arguments is that they usually have some motive behind them.
Arguments like this have emotional undertones; one hopes there is life- the other fears this is true.

I am of course biased because I hope to find life out there. I think the fundies fear the discovery of life, or an ETI if we are lucky, could cause a major re-thinking of the Abrahamic religions among followers (And possibly some others)

We all have some personal vision of the universe as we would like it, and the question of ET life hasn't been settled, allowing us to speculate on our 'ideal universe' in that sense.

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Happiness is the Earth in your rear view mirror.

I don't understand how enormous distances in space as well as time, and thus the likelihood that we will never make contact means we are "alone in the universe." ("Alone" as in the only life forms in the universe.) We just don't know.

I also note that some of the writers make the old fashioned differentiation between intelligent life (including animal life,) as opposed to life in general, such as microbial life or even plants. In reality, we don't really know what intelligent life is, including us. We just have a general notion based on ourselves.

I think our search for life mirrors our own technology: Early 20th century searches (for life on Mars) searched for shortwave radio signals, post WWII searches mirror the rise of radio astronomy, newly proposed searches visualize possible alien optical laser signals, and (as in Carl Sagan's book "Contact,") a signal that is basically a sent website with instructions. Others have proposed an interactive program sent as a signal, or aliens simply not signaling intentionally, but just putting out coherent signals as part of the activities of their "civilization." None of these speculations take into account what the alien life forms actually do or think if they exist. All these ideas mirror us, not extraterrestrials.

Fermi was brilliant, but his paradox question mirrors our concept of how an extraterrestrial advanced civilization should act. If we ever know of an actual extraterrestrial life form, I suspect we'll discover that it doesn't act or live the way we thought it should.

One exciting prospect is that as we learn more about the relationship between life on Earth and the chemistry of our planet and nearby worlds, we may have more tools with which to interpret the likelihood of life (like ours) elsewhere. I don't think we have enough tools to make sweeping statements yet.

For thousands of years man looked to the sky and wished he could fly, he never thought that wish would come true.

For thousands of years man looked to space and wished he could travel to it, he never thought that wish would come true.

For thousands of years man has looked to other stars and wished he could go to them. Be patient.

If liquid water is a pre-requisite and pressure is important then I don't see why life outside our planet should not only be possible by highly probable.
If you place enough pressure on water it will not freeze, also it will not boil until a high temperature is reached. So life can exist in a variety of environments.
Taking a look at this planet we have the smokers on the sea-bed (total absence of light) and bacteria that appear at hot spring vents that appear to have come from inside the earth. So why can't this exist in other planets?
I believe that there is a frozen lake in the South Pole area that will have some liquid water below a very thick crust of ice. If life is found here it proves that life can exist in these environments (this will have been isolated from the rest of the world) so why can it not evolve?
As for saying that our evolution would be very rare by probability is not a fair appraisal. What are your benchmarks?
Does life exist on earth by chance or is it the only possible outcome? And does the diversity of life represent the colossal number of different outcomes available?
Intelligent life as in building spaceships would be a different hypothesis I agree as there are many other factors outside nature to consider.

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"The most compelling evidence supporting the existence of other forms of intelligent life is the single fact that they haven't come to visit us" - Douglas Adams

Somewhere out there, there is a Battlestar leading a rag-tag group of civilian spacecraft on a search for our planet. Be patient - they will find us. Unless the Cylons get them first.

Aporetic

I hope that we are not alone. But it seems pretty likely.

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If ignorance is bliss, why is the world so full of misery?

Deep breath....relax....Deep breath....relax :wink: :wink: :wink:

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Democracy Now! - The lost art of investigative news reporting.

Most of you seem to be ignoring this phrase: for all practical purposes

8)

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"The oxen are slow, but the earth is patient."

I must agree, at this point in time we must function as if we are alone. Be it vast distances or an evolutionary fluke, right now we're the only game in town.

However, I can't help but muse regarding how quickly this could change (or may never change). It's certainly the prime question and I have no particular "intuition" either way.

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An open mind is like an open window...without a good screen you'll get all sorts of weird bugs!

In cases such as this where something must be true simply due to the sheere vastness of the equation then as responsible thinkers we do not infer that it is True. But we must insist that it may not be False.

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"Patriotism is supporting your country all of the time... and your government when it deserves it." - Mark Twain

What the hey. I've been avoiding ATM for a while now. This seems like a reasonable place to spray my personal brand of apathy around...

I have to side with the "What's it matter?" crowd. Even if there were ETs walking around Earth as we speak, who cares? Are they doing anything to us? Not likely. If they could get here, and mix in with us, then there's no reason to think they're plotting anything diabolical. They could just as easily whipe us out in the blink of an eye. At the very least, there'd be no path of causation for anything. Something would just happen, and no one would be able to trace it back to its source. If they're doing things FOR us, again, what do we care? Obviously, they don't want to be noticed.

If they're not here, then there're nowhere near here. In that case, we can't talk to them, and their discovery becomes a matter of trivial excitement and interest. Sure, it'd be cool, and would probably have some sort of deep spiritual impact on some (call it validation, if you will), and create a whole new breed of HBs (bitter, "my world view's been torn to shreds" types), but ultimately it would have no direct or immediate impact on our everyday lives. It would just be another cool discovery in our vast search for cool things in the universe. More knowledge for the history and science texts.

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"I'm making wheatloaf. It's like meatloaf, only with wheat"
"Isn't that just...bread?"

The opposite is true. I would love it if it were true that ET was out there. Nothing would be cooler.

In fact, it is a sad and lonely and dark thing to consider that we are alone. We are a social species. Being alone is psychologically hurting.

I wish ET was out there. But the stats don't support it.

I think it is the scientist who believe that ETI is out there are the ones that are wishful thinking. THey are often hypocrites since they often critisize other people for believing thing based on emotion and what they want to believe.

Thanks.

You saved me from having to write the same.

I don't believe that statement is correct at all. Sheer odds would point to there being ETI's out there. It's just the odds of us meeting them that are low.

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People who think they know everything are a great annoyance to those of us who do.

We could listen-in for a while. Our desire to find a means of communication will be highly strengthened by finding intelligent life. String theory with 10 (or 11 with M-theory) may allow some form of communication in the future, worm holes (possibly, but not likely), particle entanglements which occur instantly across the universe, etc. These are hints of things to come.


You are being a little generous still. GRB's may have sterlized large regions in the early days. Large stars don't last long. Small stars have problems, too. Of course, that still leaves billions of potential regions for life. 8)


Still too early to draw any solid conclusion. Mars may still have living organisms under the surface.

Good point. No doubt there really is a "sweet spot" (habitable zone) for these conditions which varys with star types. Spitzer's discovery of a planet forming within the star's accretion disk should make the subject less dry. :-? (sorry)

I wonder what the water looks like under the surface. #-o

For advanced forms of life, this appears to be a big issue.


Nice links. Sometimes it's just hard to know what we don't know. [hopefully, I am quoting someone intelligent. ]

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Lighten up! This is a stellar board!

ETI is a special case - some say there is no life at all, except on Earth. They rule out any chance of life of any kind forming anywhere else in 14+ billion lightyears of space.

I like Timothy Ferris's anaology of the search for ETI with having lobster for dinner. He sets the table, unlocks the front door and waits for a lobster to show up. The analogy reveals a failure to take into account what a lobster is actually doing.

Interesting thread you created here.

Being that I'm a woo-woo who believes not only that aliens exist, but that we've seen them visiting us forever. We've recorded drawings, pictures and stories of even ancient people seeing them in the sky. No I don't believe EVERY story is fake, mistaken or dillusional. If one of them is correct then we are NOT ALONE.

No I cannot provide hard proof of such a thing. As some scientists have said before the study of UFO's or alien vehicles is not a science at all and to study it would not prove anything. This is why were currently drooling over Mar's images being provided by the rover's up there. Either one could provide the PROOF that alien life exists, be it intelligent or not.

This question comes down a lot to peoples faith or ability to make leaps of faith. I believe in God. I also believe in the possibility that God allowed the existance of life on other planets. So for me, believing in God is not a limiting factor. For some it is.

As someone who is French, I find your slogan at the bottom of your post inappropriate to an astronomy board as well as irrational.

It's merely a joke, sorry if it offends.

No life in the universe except for us. I think that lies around in the same boat as the world is flat group. I cannot comprehend a universe without life of some type existing somewhere other then here. After all what then would be the point in the GREAT ADVENTURE we call existance.

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Just because something is improbable Doesnt mean its impossible.

That is exactly what I meant.

Meeting ET and the idea of ET being there to meet is a lot like the old saying of a tree falling in the woods without anyone being there to hear it.

If ETI is there but we wil never find it. It is, for all practicle purposes, not there at all.

Thanks for the information!

Sure there are regions for potential life. In fact, there is intelligent life in space and I can prove it:

1. The planet Earth is in space.

2. Intelligent life (sort of) lives on Earth.

To say there are no regions in space for life is going to far simply because we are here. I am just saying that for all practical purposes, we are alone because the other guys are just too far away.

That is simply not true.

Water can boil at room temperature.

I have seen this happen in High School Physics class. Put a glass dome over a cup of water and pump the air out of the enclosre. Water will boil at cold temperatures.

Sorry the education system in GB might not be up to par.

I saw this program too. He is trying to discredit the Fermi Paradox but it does not work. It is wishful thinking.

It does not apply because a lobster is not an intelligent species that would colonize the galaxy.

If we find a space lobster somewhere most people would not consider that as being ETI.

This line of thought is what causes people to become Raelians.