SETI, Drake's Equation, Alien life

[Robert TG]

This is a topic, in my opinion, where anyones guess is as good as anyone elses. I hope we can have some interesting input to this subject. There is no right and wrong answers in this as we all don't know what the truth is, but I'm interested in your thoughts on this subject.

To start, here is a link to the SETI institute site and an article from that site.
Have a look and tell us all what is your opinion on the subject?

http://www.seti.org/site/pp.asp?c=ktJ2J9MMIsE&b=178025

Here is a article from that site...

"When Does SETI Throw in the Towel?
by Seth Shostak, Senior Astronomer

“At what point would you abandon the search?”

That’s a question I get relatively frequently from folks who think that SETI may be a quixotic quest, as futile as searching for the Seven Cities of Gold. After all, modern efforts to find signals from extraterrestrial transmitters are now in their fifth decade. Could it be that those of us who still hope to tune in other worlds may be missing some writing on the wall? Some dead-obvious, chiseled text with a simple, if disappointing message: “There are no aliens”?

The question seems fair, since SETI’s obvious analogs–the historical voyages of discovery made in the centuries following the Renaissance–were completed in considerably less time than SETI has been beating the cosmic bushes. Columbus spent five weeks finding North America (and he wasn’t even looking). Captain Cook, a true paragon of explorers, and a man who mapped places that Europeans didn’t even know were places, never mounted an expedition that lasted more than three years.

But those analogs are false. The South Pacific, for all its watery wastes, is comprehensible in size. Even Cook’s unimpressive Whitby collier, powered by sailcloth, could cross the Pacific in a matter of months, come about, and cross again in a different direction. His quarry, the islands peppering the ocean like coins scattered onto a living room carpet, signaled their presence by clots of clouds even when the islands themselves were below the horizon.

The SETI wilderness is incomparably larger, obviously, and its quarry is cryptic. Even if there are ten thousand transmitting societies nestled in the arms of the Milky Way, we might need to search millions of star systems before we find one. The actual number of star systems that radio SETI experiments have carefully examined is fewer than a thousand.

It’s a simple truth, although one not universally acknowledged, that SETI is still in its early stages. Consequently, many of its practitioners will tell you that this is a multigenerational experiment, akin to building cathedrals in medieval Europe. In other words, a lot of SETI scientists will answer the question that began this article by saying “not in my lifetime, nor in that of my children or grandchildren.”

Fighting words, but could they be hyperbolic? To begin with, SETI experiments will have examined millions of star systems within a generation. And within two, we could carefully check every star in the Galaxy. The SETI ship has a lot of ocean to cover, but thanks to new technologies, it’s picking up speed. So clearly, if we haven’t found something by mid-century or so, it will be hard to argue that it’s still “early stages.”

And frankly, it’s conceivable that SETI’s basic assumptions might be proven wrong. Imagine that the new space-based telescopes (COROT and Kepler) currently being deployed to hunt for Earth-size planets around other stars come up empty. That would be a premium-grade bummer. But even if (as widely expected) they do discover rocky worlds, it’s possible that a decade or so down the line, their telescopic successors–atmosphere-sniffing instruments such as the Terrestrial Planet Finder–might fail to find any extrasolar worlds on which life has taken hold.

Spacecraft of the future might return to us the news that neither Mars, Europa, nor any of the other orbs of the solar system with liquid water have ever produced a microbe. If these are headlines of the future–if the local cosmic neighborhood turns out to be as sterile as prime-time television–then that would certainly put me on the defensive.

But the fact is that none of this incites me to break out the worry beads. Not yet. The various factors in the well-known Drake Equation, which is often used to estimate the chances of SETI success, have–at least until now–become more encouraging with time, not less. The more we learn about the universe, the more it seems disposed to house worlds with life. It didn’t have to be that way.

Somewhat more disquieting is the possibility that our approach is wrong. SETI today is overwhelmingly a search for narrow-band electromagnetic transmissions, or in fewer syllables, a hunt for beamed radio or light. We search with straightforward telescopic techniques, but it’s possible that alien broadcasts could be encoded in ways that we’re not set up to find. I’m not talking about how they construct their messages–or whether they’re broadcasting in Standard American English or a lilting Klingon dialect–but the technical scheme they use. For instance, Walt Simmons at the University of Hawaii has suggested that garrulous aliens might wield two widely separated transmitters and use quantum mechanical effects to encode their messages. The advantage would be that if we opened this type of alien mail, it would be impossible to tell from which direction it came, thereby protecting the anonymity of the sender. This sort of approach–still somewhat beyond our technical abilities–might make our present receiving schemes seem naïve.

In addition, there’s always the chance that the discovery of new physics will reveal some communication mode that’s either faster than light and radio, or requires less energy to use. This doesn’t seem likely, but science is all about surprises.

Indeed, my personal feeling is that if SETI hasn’t turned up something by the second half of this century, we should reconsider our search strategy, rather than assume that we’ve failed because there is nothing–or no one–to find. Would I ever conclude that we’ve searched enough? Would I ever truly give up on SETI’s bedrock premise, and tell myself that the extraterrestrials simply aren’t out there? Not likely. That would be to assume that we’ve learned all there is to know about our universe, a stance that is contrary to the spirit of explorers and scientists alike. We might yearn, or even need to believe that we are special, but to conclude that Homo sapiens is the best the cosmos has to offer is egregious self-adulation."

[Robert TG]

Here is a copy of Drakes equation.

N = R* • fp • ne • fl • fi • fc • L

Where,

N = The number of civilizations in The Milky Way Galaxy whose electromagnetic emissions are detectable.

R* =The rate of formation of stars suitable for the development of intelligent life.

fp = The fraction of those stars with planetary systems.

ne = The number of planets, per solar system, with an environment suitable for life.

fl = The fraction of suitable planets on which life actually appears.

fi = The fraction of life bearing planets on which intelligent life emerges.

fc = The fraction of civilizations that develop a technology that releases detectable signs of their existence into space.

L = The length of time such civilizations release detectable signals into space.

[Robert TG]

SETI has been searching for over 40 years and has found nothing. While it may be very early days of the search, I think we can already conclude that the Galaxy is not teeming with advanced aliens trying to make contact with us.

How life came to be is a mystery, and life may be abundant in the universe. But, I believe that Intelligence Life may be the rarest of all things in the universe. There have been billions of species on this planet most of them extinct and only one species has attained to a radio technology level, and that is a very recent event. Radio technology is what SETI is looking for as intelligent life.

To solve Drakes equation, you have to guess the seven unknowns in the formula and therefore any result is almost certain to be wrong.

When I plug in numbers into the Drake equation, I find I put the smallest fraction in the “Fraction of life bearing planet where intelligent life emerges”.
I guess 1 in 1 billion.

What are your thoughts about the different unknowns in the formula?

[Robert TG]

Finding a planet that is just right for life is looking for a goldielocks planet.
One that is not too hot or too cold or too small or too big but Just Right.

Our Earth is very special indeed. Not a common planet and life makes it unique in our solar system. When I look at the factors that make our planet special, I find that Earth is very special.

The distance from the Sun is important, not too hot but not too cold. But have a good look at the Moon, that shares the same orbit with us around the Sun. It's dead as. We tell ourselves that it's too small to hold an atmosphere or retain water and that is critical. While Venus is nearly the twin size of earth and is described like hell. So distance and size is critical.

What is the Minimum size a planet can be to support intelligent life?
What is the Maximum size a planet can be to support intelligent life?
If we were alive on the planet Juipter, the gravity would be so strong as to crush metal and technolgy would not develope.

What is the nearest to a star that a planet can be to support intelligent life?
What is the futherest from a star that a planet can be to support intelligent life?

Jupiter has protected earth from a lot of comet bombardment and helped create a stable enviroment for life. If a system does not has a Jupiter type planet would life develope beyond the primitive stage?

Earth has a moltant iron core that produces a protective magnetic field around the planet that defects the solar wind and harmful radiation. We would be doomed without it.

The list goes on. To me the universe is not made for life. To our knowledge it is a very deadly place just about everywhere... except Earth.

How Abundant do you think intelligent life is in the universe?

[Radar]

Hey Robert, good thread mate. I love this topic.

I think the Drake equation is flawed badly. It doesn't take into account the kinds of signals and technology that a civilisation millions of years ahead of us would be using. It also seems to lean toward the fact that intelligent life needs an Earth like planet.

I would like to see the following variables (and many others) in the equation.

TA = Chances that a civilisation millions of years ahead of us communicates with technology other than radio?

EO = The chance that any intelligent civilisation millions of years ahead of us has an ethic not to interfere with an emerging species or planet (in the same way we try not to interfere with wild life).

These are all factors that should be covered, they are all possibilities. There are many more I can think of. So in my opinion, the Drake Equation does not tackle enough angles to be accurate.

Anything that is a possibility in why we have not yet heard from E.T needs to be in the equation.

As far as life goes, it is the same physics and chemistry everywhere. As we look across the sky with our telescopes we are seeing the same objects such as stars, nebulae, galaxies everywhere. If life evolved here, and nature is any guide, it would have to have formed elsewhere to (in my opinion).

I think Seti is a good idea, but I can't see a radio signal travelling 20 light years unless the transmitter is putting out billions of watts of energy for that signal. Eavesdropping on radio signals that are not intended for inter stellar travel is going to be hard.

[Robert TG]

Radar, you’ve made some excellent points. I hope a few others will jump in to this discussion.

Life on Earth is everywhere on the planet. Microbes are found in the frozen snow of the Himalayas to volcanic vents deep under the sea. Microbes have even been found inside the cooling systems of nuclear reactors. Absolutely amazing.

And yet once we look off this planet we find a sterile Moon. Mars has had a few exciting news items about life, having a huge canal system being my favourite, but no solid proof has yet been found.

For me Mars is the key to our understanding of the amount of life in the universe.
If life is abundant in the universe we should find Life on Mars. Conditions are pretty good on Mars compared to the rest of the planets, moons, asteroids, comets etc, in our solar system. There has been water on the planet and it once had a large atmosphere making it even more favourable to foster life than it is now.

If life is found on Mars we can assume that life will somehow start when conditions are within certain limitations and that life will be found all over the universe where these conditions exist.

What would it tell us if we don’t find Microbes on Mars? I think it would basically be saying that we live in a very sterile universe. Earth is the special exception to the rule and how life started here is even a greater mystery.


With SETI, 40 years ago we had the technology to hear an Earth type radio broadcast from 100 light years away. I'm not sure how sensitive the equipment is now.

[Astro Dave]

Keep in mind guys, lack of evidence is not evidence of lack. Just means we aren't looking in the right direction, OR not using the right gear.

Imagine this: We receive a signal from another civilization. The message has travelled a thousand light years and taken as long to get here. It says, 'Hi, we're an advanced race. We know you are there and we can tell you how to cure all diseases, all wars, solve your money problems and live to be hundreds of years old. Do you want the information?"

We've waited an eternity for something like this and it has finally arrived. Excitedly we send a reply. "Yes, please send as much information you can. We are technically competent and have a fledgling space-faring capability. We even have astronomy forums!" That'll impress 'em.

Off goes the message on its thousand year journey. Our descendents eagerly await the information. One day, after another thousand years, the reply comes in and we decipher it.

You wouldn't believe it! The message reads, "What did you say?"

[Robert TG]

The message reads, "What did you say?"
LOL that's funny.
We would have to send immediately the important part of our message back to them again... "We even have astronomy forums!"




I think we all get a warm fuzzy feeling when we think of another advanced civilization in a far away place. It's a pleasant thought that, once we make contact, our small world would change dramatically. At the moment it is little more than wishful thinking.

We do have an abundance of "lack of evidence" to work with at the moment.

That is one reason why SETI is so important, if we don’t look we will never know.

Another thought is that if you were to visit a friend or relative a thousand miles away, you’d telephone ahead and let them know that you are coming for a visit. I think any ET would do the same and try and communicate with us before making the trip to visit. Any advanced civilization would know that dropping in unannounced could be considered rude. And perhaps they would also think that sending an unwanted message would be unwelcomed, and they are waiting on us to call out and ask for communication. LOL

Actually, I think SETI is looking for any radio frequencies around stars that disappear and reappear regularly indicating a revolving or orbiting planet. This is the type of transmission our Earth has been transmitting for around 100 years. It would make an interesting “Beacon” of civilization.

Of course in another 100 years we may be using some sort of laser to satellite transmission system that doesn’t use powerful radio waves and would be a cheaper and easier system with less health risks… and our Beacon would stop.

What other way is there to look at such a distance and find evidence?

Our Planet has more than it’s fair share of oxygen and that is due to plant life on the planet. We have a way to go before we can even detect an Earth size planet, but soon after that we’d be looking for the spectre of its atmosphere. Not that they would necessarily need oxygen or give it off as a by-product but because we are clueless at the moment.

[Robert TG]

I found some information on how sensitive the equipment is for searching for SETI.

"From 1995 through March 2004, Phoenix conducted observing campaigns at the 64-meter Parkes radio telescope in Australia, the 140 Foot Telescope of the National Radio Astronomy Observatory in West Virginia, USA, and the Arecibo Observatory in Puerto Rico. The project observed the equivalent of 800 stars over the available channels in the frequency range from 1200 to 3000 MHz. The search was sensitive enough to pick up transmitters with power output equivalent to airport radars to a distance of about 200 light years."

[Astro Dave]

Hmmm, before we go collectively backslapping all past endeavours think about this; Only a few years ago a Russian satellite was placed into orbit for testing before being deployed to Mars to look for evidence of past life. It had sophisticated equipment on board ready to pick up any detectable signal of life. They pointed the gizmo at Earth to calibrate the gear and guess what? The thing indicated no presence of life on this planet!!! And they were going to send this all the way to Mars to look for life? Whoa, back the truck up.

The point? Weeeel, just because the label says "made in japan" don't mean its gonna work.

Good deliberations though Robert TG and young Radar - Rob, just one point, the type of signal astronomers are waiting for is a narrowcast signal. Its a mechanical signal. Only a mechanically contrived instrument (ie/ radio station) can produce this, so when THAT happens ... open the bottle buddy.

Eeek, what if they're invaders... what then? John Wayne's dead and Big Arnie's already got a job. That leaves just ...us! Arrgh, Arr No!! Just think about that Radar, the fate of the whole world (and the forum community) would rest with us.

[CanisMajorTom]

I think SETI is a worth while cause. Exploration has always been part of human existance. For one thing, finding a SETI signal will be the biggest thing that has ever happened to humans since this site was built.

Good clip this -

http://www.myastrospace.com/vidclip29.htm

[Astro Dave]

In the clip where they are discussing the source of the signal I like the line, "...whatever it is, it ain't local!" Love it!

[Robert TG]

An excellent movie and an exciting clip. "only" 26 light years away!

It's interesting that the Alien has sent a multi level message, complete within itself and repeated the message over and over. Smart.

I still haven't been able to figure out the plaque we put on our Voyager spacecraft and I wonder if another civilization would work it out.

In the early 1970's we transmitted a message into space that should arrive in 24,000 years. Should be expect an answer from ET in 52,000 years? The message itself was cryptic having to make a 2 dimensional graph for interpretation. The message also didn't help them by supplying any information of new advanced technology, more of a hello. Then not followed up. Well, I guess it was just a stunt anyway, so not to be taken seriously.

Humans have not been able to communicate with the many other intelligent creatures on our planet, the Apes, Whales etc. The exception, we have managed to teach a few Gorillas and Chimps our language with the use of picture cards and them pointing to the pictures on a computer screen. This goes to prove these amazing animals are intelligent. Since the animals learnt our language, and we did not learn theirs, what does this say about our ability to communicate with ET? I can communicate with my dog to SIT, but not in his language.

Humans could not even figure out the ancient writings of other human beings separated by a few thousand years, until they found the Rosetta Stone that had the same message in three different languages.

Perhaps mankind will be lucky and find that all aliens actually do talk American accented English as in star trek. It sure would make our job a lot easier to understand what they are saying.

[Radar]

That is funny that the Russians could not detect life on Earth. They should focus on trying to find intellignet life in their own country first. :Chessy_Smile:

Great movie that. It was written by Carl Sagan.

[Astro Dave]

As an adjunct to that Radar... Sagan was writing the book and he came up aainst a brick wall, a sort of writers block you know.

As I recall it, in the storyline,he wanted his traveller to encounter a black hole... or reasonable facsimile thereof. He contacted his friend, Kip Thorne of Caltech, a black hole expert, and asked him what would be the outcome of someone going through a black hole. Thorne put the problem to his students and they gave Sagan a way finish the story.

[Radar]

As an adjunct to that Radar... Sagan was writing the book and he came up aainst a brick wall, a sort of writers block you know.

As I recall it, in the storyline,he wanted his traveller to encounter a black hole... or reasonable facsimile thereof. He contacted his friend, Kip Thorne of Caltech, a black hole expert, and asked him what would be the outcome of someone going through a black hole. Thorne put the problem to his students and they gave Sagan a way finish the story.

That is awesome Dave. Great story line in that movie.

[Robert TG]

There is a big flaw in the movie as far as science goes, but it added to the mystery and drama of the film. The repeated signal was sent from 25 years away and repeated itself until the scientists tested some equipment and then the signals suddenly stopped. The aliens would have had to stop transmitting the signal 25 years before to have it stop at that point. It added drama the way it was portrayed in the film.


I was thinking about how huge a problem it would be to understand the communications from an alien. As I said my dog understands the word “Sit”, but when he examines anything he uses the sense of smell. Suppose an alien has a keen sense of smell and communicated between themselves with odours from a special gland. They would have worked out electronic transmission of messages to produce not sound or pictures but various odours that they use for their language. So we intercept the message, and try and analyse it but it doesn’t make a picture or a sound, because it is meant to make an odour to communicate.

I think that it probably would be harder than this simple example to actually understand what the message from an alien is trying to communicate. If we ever received a message, I doubt we will know what it means and have very little hope of working out the meaning. They may have a totally different set of sensors and way of communicating. Still the message would be clear “We are not alone”.

[Astro Dave]

I think we're all missing the point. It really matters not what, in essence, a message from another civilization means. Its the fact that we got a message in the first place!

You see, the whole premise of SETI is that 'someone else' may be out there and that that 'someone else' might just be sending a signal in our direction.

The premise pre-supposes that we are not alone, and that is the question we want answered. Evidence that we're not the only ants in this nest.

Picking up a signal - of any type - as long as it was intentional and mechanical is all that's needed. What's in the signal isn't so much. Good if you got a decipherable message but, as I said, not entirely necessary for the exercise.

[Robert TG]

Still the message would be clear “We are not alone”.

What else would we know if SETI is sucessful?
We could work out the direction and distance of the signal and therefore the time it was sent. We could also work out the power output the transmitter was that was used by ET. We probably could work out if the signal was sent intentionally. If so, it would indicate a desire to communicate. If not, perhaps they think they are alone.

Would our world start to transmit a message back and what would it say? Whatever the message says, ET would probably have as hard a time understanding what we sent. But they would know that we have transmitted a message to them and want to communicate and they are not alone. I suppose that our politicians would send a message stateing that we want PEACE. A sure indication that we don't have that here on our own planet.

That is nice if ET is 25 light years away, but if ET was 26,000 light years away... would there be much point in responding? Certainly not in a rush.

[Robert TG]

"For if advanced civilizations are going to communicate with one another, it is no good sending words in any particular language: instead something in the form of a message that a computer can decode will be most likely to have success.
Of course we do not know what form of computers another technological civilazation might have developed, but we can be reasonably certain that they will not only possess such a devices, but also that they will use some form of on-off, or binary, switching. Binary coding is not difficult to understand."

A series of binary signals can be sent to paint a picture. If these ET can see then they might like a pretty picture.

"So we could send picture messages to other civilizations using a binary code which we would expect any technically advanced civilization to understand."

"The message sent in 1974 contained 1,679 consecutive on-offs arranged in groups, gave a picture of a DNA helix, a human being, the Arecbo telescope as well as some atomic details and a map of the solar system. It will take 24,000 years to reach the globular cluster M13 in Hercules."

"The cluster has some 300,000 stars."

I have seen the picture that this 1,679 on-offs signal would produce. I would wear out a bald spot scratching my head trying to work out what the on-off dots represent. And I know what a human looks like! Imagine poor ET getting that signal and then waiting for something more from us as the years go by.

Well, at least, we can say... we tried. LOL

What message could we hope for that ET would send us?

[Tenacious Del]

There are so many angles to this discussion. It is interesting to think about how ET would communicate. Like Robert says they may communicate with smell. Dolphins see with Sonar, so it is not unrealistic that ET may use something like this. But what if we were never born with a sense of smell? Then we would have no concept of odours. Which means there may be sensors that ET has and communicates with that we have no concept of.

[Robert TG]

"So, where is everybody?" Nobel laureate Enrico Fermi reportedly quipped to fellow physicists in 1950, when discussing why we haven't seen any signs of alien civilisations if, as many believe, our galaxy is teeming with life. Now, a maths model may have an answer to Fermi's paradox.

Rasmus Bjork of the Niels Bohr Institute in Copenhagen, Denmark, has calculated that eight probes - travelling at a tenth of the speed of light and each capable of launching up to eight sub-probes - would take about 100,000 years to explore a region of space containing 40,000 stars. When Bjork scaled up the search to include 260,000 such systems in our galaxy's habitable zone, the probes took almost 10 billion years - three-quarters the age of the universe - to explore just 0.4 per cent of the stars (http://arxiv.org/abs/astro-ph?papernum=0701238).
So, Bjork's answer to the Fermi paradox: aliens haven't contacted us because they haven't had the time to find us yet.
He adds that the search could be optimised by visiting only those stars that harbour habitable planets, which could be identified by planet-finding missions such as NASA's Terrestrial Planet Finder. Bjork is also "cautiously optimistic" about listening out for aliens with radio telescopes."





I wonder how Rasmus Bjork got the idea that Aliens would send only eight probes?

What would happen to his calculations if they sent out 8 probes each year, or sent out 8 million probes every year?

What would aliens have done if they came across our planet 10,000 years ago? Or even if they scanned us from afar, for radio signals 150 years ago?

How much effort would an advanced civilization put into finding another advanced civilization?

If our civilization is anything to go by, and it is the only civilization to go by, the answer is the bare minimum of searching. Of course we have only recently been advanced enough to search so this is early days. Mankind’s curiosity will drive it to keep searching. I suspect that curiosity has to be a trait of all intelligent beings otherwise the advanced technology would never be found.

If our galaxy is teeming with intelligent life the question really is...
"So, where is everybody?"

After 40 years of SETI, I conclude that our galaxy is Not Teeming with intelligent life.

[Robert TG]

I have celebrated Australia Day by re-watching the movie "Contact". It is an inspiring movie with many well thought out ideas.

[Robert TG]

http://www.seti.org/site/pp.asp?c=ktJ2J9MMIsE&b=179070

[Radar]

I think this galaxy could be teaming with life and I think SETI may not yet have what it takes to find life.

The chances of an alien civilisation being at exactly the same point in technology as we are would be infinitessimal.

So Aliens are either really really primitive or millions of years ahead of us.

If they are primitive life forms (bacteria), we won't hear their signals because they don't transmit any.

If they are the other option, then they are so advanded, that our technology would be a ridiculousy primitive to them and something they probably stopped using millions of years ago.

And when it comes to Aliens that are millions of years ahead of us, they would be not only more advanced than we assume, they would be more advanced than we can assume. Trying to tackle what techologies and sciences will be available to humans in a million years is impossible.

Also, like Humans, Aliens may have an ethic of not interferring with Nature (in this case, emerging civilisations). And may want to stay unseen until a more appropriate time.

Glad you watched contact again Robert. I own a copy of that and get my fix about twice a year.

Now, on that note (Contact), the Einstein Rosen Bridge is a theory that allows extremely fast travel (worm holes). So Rasmus Bjork to suggest that aliens would send probes that take thousands of years to establish contact is an old fashioned way of looking at things. Especially when you take into account that any civilisation that is ahead of us, will be millions of years ahead of us.

Rasmus Bjork (when thinking of Aliens) automatically assumes that they would be at the same level as us when it comes to technology. Not so, they would be millions of years ahead of us.

So what is more likely, probes being sent from a civilisation that is millions of years ahead of us? Or something along the lines of the Einstien Rosen Bridge?

:crazy:

P.S Great topic this, who started it?

[Astro Dave]

Robert started it, I think. Robert, where do you get the time to write all this and still manage to interact socially with other human beings.

? SETi et al - Cool stuff. Check out the WOW signal for a nifty look at what could have been.

http://www.bigear.org/wowmenu.htm
'

[Robert TG]

Dave, ? "still manage to interact socially with other human beings"? LOL

Some good articles there on the WOW! signal. I like this quote...

"So was the Wow signal our first detection of extraterrestrials? It might have been, but no scientist would make such a claim. Scientific experiment is inherently, and rightly, skeptical. This isn't just a sour attitude; it's the only way to avoid routinely fooling yourself. So until and unless the cosmic beep measured in Ohio is found again, the Wow signal will remain a What signal."

What the signal was, or could have been is interesting as almost all other explanations were ruled out.

[Robert TG]

All the planets in our solar system have been hit by meteors large enough to blast bits of that planet into space. It is thought there are bits of Mercury, Venus, Mars and the Moon, to be found on Earth. Likewise bits of Earth should have made their way to these other planets. Could Earth life survive the journey to Mars? Conditions on Mars are friendly enough for some forms of earth’s life to live there. So there is a real possibility that we have cross-pollinated Mars with life that started on Earth.

Mars is the key and exploring Mars will help unlock the mystery.
Earth is saturated with life and it would seem that once life started here, it adapted and covered the planet.

If we explore Mars and find that “No Life” has ever existed there, then conditions for life to spring up on it’s own in other locations in the galaxy is severely limited and reduces the possibility of abundant life being found everywhere.

If we do find life on Mars had existed at some point, it will need to be examined carefully to see if it’s origin is from “Mother Earth”. If it’s proves to be truly extraterrestrial then we should expect life springing up where ever conditions are right. (What ever they may be)

The Universe is not a friendly place for life to exist. The cold vacuum of space, radiation and cataclysms exist everywhere. If you look at the universe as a whole, with all the material spread out among all of space, it would best be described as empty. A more perfect vacuum than what we can produce here on Earth. It’s just lucky we have the clumps to live on within a whole lot of nothing.

We still do not know how life started on Earth so it is equally possible that life is common or unique. Still, it goes against our logic for anything in this Universe to be completely unique, yet the technical level of human intelligence is unique on this planet.

[Robert TG]

[QUOTE=Robert TG;1005]Here is a copy of Drakes equation.

N = R* • fp • ne • fl • fi • fc • L

QUOTE]
Just plugging in some numbers into drakes equation

R* =The rate of formation of stars suitable for the development of intelligent life. I'd guess about 200 per year

fp, I'd guess 50% would have planets

Ne, I'd guess 1 planet in each system on average would be like earth

fl, I'd guess .001 (one in a thousand) might produce life

fi, I'd guess .001 (one in a thousand) might have intelligence

fc, I'd guess .001 (one in a thousand) might develop technology

L, I'd guess 10,000,000 (ten million years) the civilization will last

N= 200 x .5 x 1 x .001 x .001 x .001 x 10,000,000 = 1 (that is Earth)


As you can see the numbers are just simple guesses and I did fiddle with my guesses to make the equation equal "one".

Change a few numbers and you get millions of civilizations or the steep odds against our very own existence. LOL

I'm interested to know ...What numbers would YOU put into this formula and WHY?

[Radar]

I'm a lot more optimistic.

fp, I'd guess 50% would have planets

Ne, I'd guess 1 planet in each system on average would be like earth

fl, I'd guess 50% might produce life

fi, I'd guess 10% might have intelligence

fc, I'd guess 100% might develop technology (after time)

L, I'd guess (I'm not sure what this part means Robert) the civilization will last

N= And I have no idea how the answer works :duh:

I don't think SETI is using technology that is setup to eavesdrop properly on ET's radio traffic that is millions of years more advanced than ours. So I'm optimistic.

[Robert TG]

Yes, on second thought, I'll correct my post above to reflect the nature of the formula.
R* =The rate of formation of stars suitable for the development of intelligent life.
L = The length of time such civilizations release detectable signals into space.

But as you say they would advance away from Radio signals...so perhaps we should say they use the signals for just 1000 years, that would mean we should still detect 5,000 civilzations using Radio.

On your figures the formula and 1,000 years ...

N = R* • fp • ne • fl • fi • fc • L
N= 200 x .5 x 1 x .5 x .1 x 1 x 1,000= 5,000 Civilizations

[Robert TG]

What do you think of how Hollywood has portrayed their ideas of Aliens?

Some old movies...

3 killer Aliens
The Thing from other space:
A very old movie where one alien arrives on earth. Looks like a large man but is a vegetable and starts to multiply by spores killing people because it lives on blood. (vampire movies where popular at the time)

Alien:
A creature that just loves the horror of killing

Predator:
A creature comes to earth for the sport of hunting humans

3 Alien Machines
Forbidden Planet:
Another old movie where the aliens have died off leaving a fantastic machine that increases brainpower.

Contact:
Another unknown alien civilization leaves a machine that another alien civilization uses and tells us how to build.

Stargate:
Yet another Alien leaves behind a fantastic machine to travel through space.


4 other Alien films
The Mysterians:
Men from the PLANET MYSTROID come to earth and want to mate with our women.

ET:
An Alien hides out with a couple children in the USA, and goes trick and treating.

The day the Earth stood still:
Earth is shocked when an alien man lands in a flying saucer in Washington DC

Star Trek the movie:
Voyager returns to earth as a new machine. Not really an alien…but met up with Alien machines from an unknown source.

[Radar]

Whilst Alien movies are merely science fiction, nothing can be ruled out in my opinion.

The aggression and killing ability of the Alien in the movie Aliens is quite feasible, when you look at some of mother natures Dinosaurs. Triceratops with it's three horns, Stegosaurus with it's tail of one metre spikes and blades on it's back, Velociraptor with it's retractable claws or even Astro Dave. Nature can sure make up some nasty creatures. I for one would not like to meet these creatures in a dark ally. :Chessy_Smile:

Humans hunt Lions in Africa for sport, so why not Predator hunting humans that to them, would appear as primitive life forms.

I think what makes Alien movies so intriguing is that the possibilities are endless.

[Robert TG]

We marvel at our own technology and human intelligence. The fact is that few if any human could develop a radio if left to his own devises. There have been a few remarkable humans who have invented different technologies and they learnt the basics from the great men who went before them. "Standing on the shoulders of giants".

So human technological intelligence is a group effort.

The Human creature itself has not grown more intelligent as a singularity, but lives in a society that teaches each generation the technology of the past on which to build upon.

With this in mind I would say that ET would have to be a social creature and not a lone creature.

Creatures that live a solitary life (say for example a polar bear) would have little chance of developing technology. While creatures that live in a herd, pack or other social group stand a much better chance.

Ants are a good example of a different civilization to ours. They are not an advanced civilization but a very old one. Proving that just having a long lasting civilization does not necessarily mean great advancements in technology.



Please post what you think would be a trait any ET would have.

[Robert TG]

R = the number of suitable stars — stars like the sun — that form in our galaxy per year

Note: Astronomers estimate that this number is about 1.




Fp = the fraction of these stars that have planets

Note: Probably at least half of all sun-like stars have planets. Most stars are too small to gravitationally support a planetary system, while some stars have too short of a life span.




Ne = the number of Earth-like planets — meaning planets that have liquid water — within each planetary system

Note: For the Solar System, this number is at least 1 — the Earth, and perhaps more, if Europa or other moons turn out to have oceans



Fl = the fraction of Earth-like planets where life develops

Note: For example, if you think all Earth-like planets produce life, your estimate would be 1. If you think only one in ten such planets produce life, your estimate would be 0.1.



Fi = the fraction of life sites where intelligent life develops

Note: For these purposes, we define intelligence as having a symbolic language — like mathematics, or English or Japanese — since language is required for communication. If you think every planet with life produces intellegent beings sooner or later, your estimate would be 1. If you think only one percent do, your estimate would be 0.01.




Fc = the fraction of intelligent life sites where communication develops

Note: There could be intelligent beings who haven't yet invented radio telescopes (We humans belonged to this category until the 20th century). Or there could be others who have the means to communicate but don't — perhaps because they are not interested or fear that they might endanger themselves by advertising where they live.



L = the "lifetime" (in years) of a communicative civilization

Note: Humans have been communicative for less than 100 years. Do you think we, or the average intelligent species remains willing and able to communicate with other star systems for only a century? A thousand years? A million? Your guess is as good as the experts'



N = The number of communicative civilizations within the Milky Way today.



N = R* x fp x ne x fl x fi x fc x L

My guesses
N= 1 x .5 x 1 x .01 x .000000001 x 1 x 10,000,000 = .00005 as my estimate of how many communicative civilizations exist in the Milky Way. Since we exist, I'm already out by a large factor.

[Robert TG]

Frank Drakes origional estimates

N = R* x fp x ne x fl x fi x fc x L

10,000 = 5 x .5 x 2 x 1 x .2 x 10,000


While some of these factors can be estimated by scientists there are other factors that your guess is as good as theirs.


.

[Robert TG]

It is interesting to note that Intelligent life arose on the Earth about 4.55 billion years after it formed.

If that is unusually long, or unusually short, or quite typical is unknown.

[Robert TG]

Another trait that ET would have to have is a manipulative ability which makes possible the use of tools.

We have hands, an intelligent ET would need to have some way of manipulating his enviroment. In other words, a Dolphin would never develope radio.

[Astro Dave]

That's quite a number of posts there Robert old chap... you wouldn't be trying to usurp my ranking by loading the bases at all? Tsk Tsk.

By the way Robert, I'm now "Jupiter Crew" Howzat!!

It's all thanks to good 'ol Radar ... number one genuine good guy AND he's just been made my 'first best friend.'

[Radar]

It's all thanks to good 'ol Radar

How could I refuse that monetary offer you made Dave?:Chessy_Smile:

[Robert TG]

That's quite a number of posts there Robert old chap... you wouldn't be trying to usurp my ranking by loading the bases at all?


No I wasn't thinking about the number of posts, I was just trying to get some other members thoughts on the subject. Turned into a monolog with not many others with input or interest in this subject.

Congratulation on your Jupiter status. How’s the little Red, the other Red Spot on Jupiter doing?

[Astro Dave]

Hi Robert - All spots doing quite well, thank you all the same.
I think we should reward Robert with a prize ... recognition for being our 'deep thinker of the year'

By the way Radar ...Shhhhh. (Stay cool about the payola, OK?)