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have they found anything?

we should be/are aiming the signals at these, i.e. to one side of the star, hoping that we would hit something within planetary orbits and repeating this after a certain period, in case one potential planet was behind its corresponding star, at the time of the first signal.

It's called Active SETI.
 
Supposing our radio transmission is picked up by an alien intelligence say, one hundred light years away. We would say, ''hello we are here'' or whatever it is we are transmitting. A reply would take a hundred years to get here and say ''so are we'' Not exactly a conversation starter is it? But at least we would find out we are not alone and perhaps kill off religion once and for all.
 
Supposing our radio transmission is picked up by an alien intelligence say, one hundred light years away. We would say, ''hello we are here'' or whatever it is we are transmitting. A reply would take a hundred years to get here and say ''so are we'' Not exactly a conversation starter is it? But at least we would find out we are not alone and perhaps kill off religion once and for all.

Yup--on the Active SETI Wiki page I just cited, we've yet to reach the arrival date of any of our messages. (So far, the ones aimed at the Super-Earth sized planet Gliese 581 will arrive first--in 2029-2030.)

Plus, as I said, we only sent these directed signals for a matter of minutes each, I believe. So the recipient would have to have their gigantic radio telescope pointed at us and listening or recording our signal at exactly the right moment. Given the huge distances and long times involved, this is about like randomly plucking out a piece of straw from a super-gigantic haystack. We're not likely to find a needle that way.

So, not finding a needle that way doesn't argue that no needles are in the haystack.

And who knows? We might just get fabulously lucky some day.
 
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I doubt that ET will ever communicate with us in our and or our grandchildren's lives.But having said that, who knows what the future holds. If they exist, and a technological civilization has not a limited life span as Earth seems to have what, with overcoming global warming, overpopulation, and hostilities between religions and race, The universe is the limit.
 
Finally, a post that actually makes sense! :D Those limitiations you list are probably an indication that we can't be counted as an intelligent species yet. ;)
 
What's the point of living at all if not to explore?

Do we just be born, make babies, and die, ad infinitum until some cosmic catastrophe wipes us out permanently?

We're doing what we can with the exploration of local planets, and it is a worthwhile endeavor, but SETI is the only program we have which is even capable of saying "Yes, there is intelligent life in this Universe besides us." The dizzying prospect of answering this question at all makes SETI one of the most important exploration programs run today, in my opinion.

Personally, I think we're not doing enough and should be devoting more energy and resources to broadcasting directed, long-term, repeating messages toward high-probability target systems. Maybe everyone out there is listening and no one is broadcasting. Our omnidirectional radio broadcasts are diminishing greatly after only a few decades of having the technology. Let's take the initiative and let the Universe know that we're here in no uncertain terms. Consider the few messages that have been sent so far. If those messages were detected by SETI, would they even qualify as a hit? Would those messages be interpreted as just another "Wow!" ? (edit: It appears Active SETI has done just this a couple times -- though with few repetitions. Hopefully that's enough!)

Amb makes a good point about when the detection may happen. Unless there are projects in other systems to send out a continuous pulse saying "we're here," then we're unlikely to hear anything but a reply, which will take many years to arrive. A more likely scenario than picking up a stray, repeating radio signal is that other civilizations are listening, just like us, and when they detect a faint signal from some direction, they shoot a focused "we hear you" right back.

I also think we have an obligation to reply with a clear message of "we hear you" should we ever detect a stray signal.

Apologies if this has been covered already, I didn't have the time at the moment to go over 24 pages of posts. =) I just wanted to throw out my position (and creep a little closer to 50 posts ;)).

edit- I just noticed the discussion of Active SETI. Fantastic. =)
 
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Seti is not the only way of exploration of a home for life as we know it. In March the Kepler spacecraft was launched. This is the most sophisticated effort yet to look beyond our own solar system for planets orbiting other suns. If the telescope can spot a rock similar to our own, it could be a strong indication that life is possible on another planet.
From Science illustrated magazine
 
But this rock needs to be in the habitable zone with liquid water among other essentials for life to evolve to at least animal intelligence.
 
But this rock needs to be in the habitable zone with liquid water among other essentials for life to evolve to at least animal intelligence.


Really? Why? Just because that's the way it happened to have worked here, doesn't mean that it's universal. I know you kept going on about the "rare earth" conditions in all your posts, but did you get a chance to watch the "Becoming Human" series on Nova? Basically our evolution had stagnated for several million years, UNTIL drastic changes to the environment and the like happened. Maybe this planet is too stable and nice to really help intelligence evolve, and you need more chaos (Man, I feel like I am channeling a "shadow" from Babylon 5!).

You cannot, and should now, make those assertions. We have one datapoint, and that's it. Evolution is much more cunning than any of use dumb apes could ever imagine being.

OH CRAP, HERE WE GO AGAIN!
 
Yet, the universe is around 15 billion years old, and Fermi's Paradox still stands like a beacon in the night.

We still have the very same bacteria that evolved on Earth 4 billion years ago.
 
Yet, the universe is around 15 billion years old, and Fermi's Paradox still stands like a beacon in the night.

OH CRAP, HERE WE GO AGAIN!


You said it.

Amb, please see my numbered list on Fermi's Paradox. Any one of those points pokes a hole in the idea that Fermi's Paradox means intelligent life is rare (the way you mean rare).

And the universe is around 15 billion years old everywhere. No more time has passed in one place than in another place.

By your thinking, the fact that there is not ubiquitous evidence throughout the galaxy of our own existence argues that we don't exist.
 
Seti is not the only way of exploration of a home for life as we know it. In March the Kepler spacecraft was launched. This is the most sophisticated effort yet to look beyond our own solar system for planets orbiting other suns. If the telescope can spot a rock similar to our own, it could be a strong indication that life is possible on another planet.

Kepler is not looking for life. "Looking for a home for life" is not the same as looking for evidence of life.

By the way, I think this post was an improperly credited quote again.
 
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Yet, the universe is around 15 billion years old, and Fermi's Paradox still stands like a beacon in the night.
Rather than repeat this over and over again, why don't you first address the arguments made against it?
 
No we don't.

The point I was making is that some bacteria has not over millions of years built a civilization. A marine animal like a shark has been a shark for millions of years with no change in it's physical appearance, or very little. Out of the billions of life forms on this planet, only homo has been able to build a civilization.
What if other worlds, Earth like planets, the same thing happens? The asteroid that collided with the Earth and almost caused a complete extinction 65 million years ago is not a given on each and every planet in the cosmos. It was this event that started the evolution of homo erectus and finally us.
Do we know how many stars are as stable for billions of years as our own sun?
Do other planets also evolve an ozone layer to protect any life forms from the deadly ultra violet light? Mankind needs a life support system if he is to go to any other planet or moon in our solar system. Yes, I acknowledge that life evolves according to the conditions, that's why I insist that microbial life is probably even found in our own solar system. I also acknowledge that because of the sheer numbers involved, there has to be other Earth Like civilizations out there somewhere. But what I think is that intelligent life is out there, but not on a scale most people think. The coincidences that allowed us to evolve to what we are today are too great for it to be otherwise.
 
The point I was making is that some bacteria has not over millions of years built a civilization.
And in what way do you think that's meaningful?

What if other worlds, Earth like planets, the same thing happens? The asteroid that collided with the Earth and almost caused a complete extinction 65 million years ago is not a given on each and every planet in the cosmos. It was this event that started the evolution of homo erectus and finally us.
But the dinosaurs were still evolving. They weren't just unchanging for millions of years. There's nothing that would have prevented some species from becoming intelligent, and technological.
Which of course doesn't mean it would be inevitable, but neither of us knows the probabilities.

Do we know how many stars are as stable for billions of years as our own sun?
I'm pretty sure we have a good idea, as the lifetime of a star can be deduced from it's mass, colour, etc.

Do other planets also evolve an ozone layer to protect any life forms from the deadly ultra violet light?
Is ultraviolet light necessarily deadly? Life on earth existed for a long time before we had an ozone layer. There's no reason to believe that ozone layers are necessary for technological civilizations.

The truth is, we don't know what's necessary.

Mankind needs a life support system if he is to go to any other planet or moon in our solar system. Yes, I acknowledge that life evolves according to the conditions, that's why I insist that microbial life is probably even found in our own solar system. I also acknowledge that because of the sheer numbers involved, there has to be other Earth Like civilizations out there somewhere. But what I think is that intelligent life is out there, but not on a scale most people think.
What is the "scale most people think"? How rare do you think ET civilizations are?

The coincidences that allowed us to evolve to what we are today are too great for it to be otherwise.
Unsubstantiated assertion. Again.
 
Civilization= cities, technology, communication over thousands of miles, the mapping of the human genome, a heart transplant, jets able to fly faster than the speed of sound, nuclear bombs able to destroy every living thing on this planet except perhaps cockroaches, and most of all, intelligence enough to ask these questions.
 
That seems a very anthropocentric definition, regardless. It seems you're defining civilisation as "everything we've done".
 
What other species on this planet has done any better? Someone has said that perhaps if the dinosaurs weren't made extinct when they did, they perhaps may have started a civilization. Well, they were here for much longer than homo sapiens who has only been here for around 200.000 years compared to over one hundred million years for Dino.
 
What other species on this planet has done any better?

And of course that's not the question SETI seeks to answer.

I've pointed out several times that if you prefer to count the Earth as 1 for a trillion (ratio of species to develop an intelligent civilization--for a given definition--to the total number of species ever to have existed), it doesn't help the Rare Earth case any compared to treating the Earth as 1 for 1 (one intelligent civilization per habitable planet).

If you change the definition of that ratio here, you simply have to use it consistently throughout the galaxy.

Why not make the following observation? The total number of intelligent species on Earth to attain radio technology and endure with at least that technological level for 1000 years is zero. Does that mean we're not an intelligent civilization?

After all, your argument based on the Fermi Paradox uses the lack of ubiquitous evidence of an extremely long-lived intelligent civilization as evidence that they don't exist. So do you conclude that we don't count as an intelligent civilization? It's the same logical approach.
 
What other species on this planet has done any better?
I beleive that he was asking better at what? You can't say, "civilization is what we have done." and then to back up that definition say, "no other life on earth has done better at it."

So, no other life on earth has done better at doing what we've done. Um, that's completely tautological.

Someone has said that perhaps if the dinosaurs weren't made extinct when they did, they perhaps may have started a civilization. Well, they were here for much longer than homo sapiens who has only been here for around 200.000 years compared to over one hundred million years for Dino.

"Dinosaurs" are not a species, homo sapiens are. You're not comparing like with like.
Mammals, on the other hand, have been around for a very long time. But it was only very recently that they started a civilization. If we'd looked at mammalian life on earth ten million years ago, you could have said much the thing about it that you just said about dinosaurs.

None of that suggests that it would have been impossible for some dinosaur to evolve intelligence similar to what we have today. Hell, some of them have evolved toward much greater intelligence. See crows, for instance.
 
I prefer the term METI = Messaging to Extraterrestrial Intelligence:

Quote from my paper "Messaging to Extraterrestrial Intelligence:"
The science known as SETI deals with searching for messages from aliens. METI science deals with the creation of messages to aliens. Thus, SETI and METI proponents have quite different perspectives. SETI scientists are in a position to address only the local question “does Active SETI make sense?” In other words, would it be reasonable, for SETI success, to transmit with the object of attracting ETI’s attention? In contrast to Active SETI, METI pursues not a local and lucrative impulse, but a more global and unselfish one – to overcome the Great Silence in the Universe, bringing to our extraterrestrial neighbors the long-expected annunciation “You are not alone!”

Alexander Zaitsev.
(Unfortunately I can not give the link to my paper, because I am a newbie).
 
We aren't going to know until the Kepler telescope picks up an image of a rocky planet orbiting some other star at or near the Goldilocks position for mankind to be sure he's not alone, at least in this part of the galaxy. The next few years will either confirm it or not.
If rocky planets are rare, or not too close to it's star, then the chances are good.
Of course we are talking of life as we know it based on carbon.
 
I prefer the term METI = Messaging to Extraterrestrial Intelligence:

Quote from my paper "Messaging to Extraterrestrial Intelligence:"

Alexander Zaitsev.
(Unfortunately I can not give the link to my paper, because I am a newbie).
You can post a pseudo-link (you won't get in trouble) just inserting a space or spelling out the "dot" or something like that.

ETA: I didn't find the paper you mentioned, but I found the Wiki article on CETI and on yourself. Also of note: there's an entry on you in David Darling's encyclopedia. (Darling's Life Everywhere came up on this thread a while ago--particularly his chapter debunking the Rare Earth book. Great to have your expertise here! </ETA>

Maybe you know more about these projects. Do you know how long a duration any of the focused signals we have sent out have been? Also, have you done any calculations on the economic feasibility of sending a long-term focused signal? My own suspicion is that it will probably never be economically feasible. Our demand for energy is still increasing, so I doubt such massive non-stop consumption of kilowatt hours will ever be feasible.

I can still hear my Dad harping at us to turn the lights off when you leave a room. A long term message would be the ultimate in leaving a lightbulb burning!

We aren't going to know until the Kepler telescope picks up an image of a rocky planet orbiting some other star at or near the Goldilocks position for mankind to be sure he's not alone, at least in this part of the galaxy. The next few years will either confirm it or not.
Well, Kepler might give us a better estimate for one more factor in the Drake Equation. I don't think we'll know anything more than a better estimate of the number of Earth-like planets there are. And since the section of the sky Kepler will look at might not be typical, that estimate may or may not be accurate anyway. (Kepler is going to be a sampling and not a whole-sky survey. Its planet-detecting technique requires looking at the same group of stars for a couple of years.)

amb said:
If rocky planets are rare, or not too close to it's [sic] star, then the chances are good.
I don't think you mean this the way it's written. If rocky planets are rare, chances are good, for what?
 
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Dr. Zaitsev, I would be very interested in hearing more from you about some of the major "bones of contention" in this debate. :) I am not actually an authority in this field, so I am going by what I have educated myself on, logic, and the attempt at removing as much human bias as possible.
 
I meant if rocky planets are the norm. [sorry]
Ever think that we may be the first intelligent beings in the cosmos? It's not hard to imagine.
The universe is 12-15 billion years old right? The first generation of stars had to have lived then some gone supernova so as to spew the carbon, iron, and all the other elements manufactured in the stars core into space. How many billions of years would that take before planets and finally life is formed? Some gigantic stars would have a short lived life, but produce very little carbon and the other elements.
Our sun is at least a third generation star. But not all stars like our sun live up to 10 billion years, some are known to be older than sol.
 
I've just read your paper, and I have a question and a comment.

First, in Table 2, on the number of sessions and duration of the signal in minutes, is that time a total duration of all sessions or is that the length of time for each session? (In other words, are we talking about 5 sessions of 900 minutes each, or 5 sessions that total 900 minutes?)

My comment is related to the above question and your question/dimension number 2, "When to send IRMs to the selected star?" While I like the idea of timing a signal to coincide with some large event (like an extra galactic nova that's more or less in-line with us and the recipient start) to draw attention to our part of the sky, but I still think it's a needle in the haystack. Are the costs of setting up a "permanent" sort of beacon aimed at the same star indefinitely prohibitive to such a project? (I guess my comment is a question after all.)

OK--I've got another question for anyone with the technical knowledge: is there anything in between omnidirectional broadcasting and this sort of message targeted at a single star? Could we send a signal with enough power (or whatever) to be detectable at some distance (say a few hundred light years) that would target a larger cone before it gets too diffuse for anyone to receive? Could we feasibly target a larger group of stars?
 
To: JoeTheJuggler
The symbols T and E here represent the total transmit duration in minutes, and radiated energy in Mega Joules, of each of the four METI projects conducted to date.
So,the total duration of all 1+4+6+5=16 transmissions is about 37 hours, only.

We use Evpatoria Planetary radar very rare, when we have money for leasing 70-m dish and power, water cooling, transmitter.

More info about all transmitted IRMs you can find at Wiki category "Interstellar Messages":

h_t_t_p://en(dot)wikipedia(dot)org/wiki/Category:Interstellar_messages
 
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To: LarianLeQuella

Please visit Wiki category "Interstellar Messages":

h_t_t_p://en(dot)wikipedia(dot)org/wiki/Category:Interstellar_messages
 
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To: JoeTheJuggler So,the total duration of all 1+4+6+5=16 transmissions is about 37 hours, only.

We use Evpatoria Planetary radar very rare, when we have money for leasing 70-m dish and power, water cooling, transmitter.

Yup--still a infinitesimally tiny needle in a humongous haystack.

And again, I suspect the reason we haven't detected messages directed at us yet is the cost/motivation issue. For someone to send a focussed signal at us for a substantial time period (say 10 years or 100 years continuously), would undoubtedly be a huge economic strain--perhaps prohibitively so.

And on the scale of the galaxy, even 100 years is an eyeblink.

While I applaud the work you're doing, I still disagree with amb that the lack of evidence for an ETI to date means that they don't exist or that they are particularly "rare" (in the sense he means "rare"--which is no more than a few in the entire galaxy).


More info about all transmitted IRMs you can find at Wiki category "Interstellar Messages":

http://en.wikipedia.org/wiki/Category:Interstellar_messages
Not really more information. All this information is either on or linked to the Active Seti Wiki article I linked to at the beginning of top of this page of the thread.
 
...I still disagree with amb that the lack of evidence for an ETI to date means that they don't exist or that they are particularly "rare" (in the sense he means "rare"--which is no more than a few in the entire galaxy)...
In order to overcome huge interstellar distances, Planetary Radar's beam was made very, very narrow -- it occupy 1/10,000,000 (one / ten millions !!!) part of celestial sphere.

Similarly to transmission, when we make SETI, we also use very large antennas with very, very narrow beam, also, about 1/10,000,000 (one / ten millions !!!) part of celestial sphere.

So, you can estimate the probability of the event when transmitting and receiving antennas directed accurately to each other as as production 10**(-7) x 10**(-7) = 10**(-14) !!! only

You see, in order to be justified to say the ETIs are not exist, we must have very powerful SETI multi-beam antennas around all globe, which make SETI during long time interval, I guess...

:)
 
In order to overcome huge interstellar distances, Planetary Radar's beam was made very, very narrow -- it occupy 1/10,000,000 (one / ten millions !!!) part of celestial sphere.

Similarly to transmission, when we make SETI, we also use very large antennas with very, very narrow beam, also, about 1/10,000,000 (one / ten millions !!!) part of celestial sphere.

So, you can estimate the probability of the event when transmitting and receiving antennas directed accurately to each other as as production 10**(-7) x 10**(-7) = 10**(-14) !!! only

And that doesn't even take into account time. Most times even when you line up a receiver with a transmitter, the signal won't be there since the signal only lasted a matter of minutes or hours.
 
We are still assuming that ET is around our age, perhaps a little older or younger.
But what if ET is a billion years older? No matter where in the galaxy he may hail from, his technology would seem like magic to us, surely able to pick up our feeble attempts at sending out any signal. He could be watching re-runs of Hogan's Hero's right at this very second. This kind of ET would want to colonize the galaxy if it hasn't already done so.
 
And that doesn't even take into account time. Most times even when you line up a receiver with a transmitter, the signal won't be there since the signal only lasted a matter of minutes or hours.
Yes, you are right about time! Even more, I would like to say about frequency band -- our receiver and ETI's transmitter may have not frequency match...
 
We are still assuming that ET is around our age, perhaps a little older or younger.
But what if ET is a billion years older? No matter where in the galaxy he may hail from, his technology would seem like magic to us, surely able to pick up our feeble attempts at sending out any signal. He could be watching re-runs of Hogan's Hero's right at this very second.

No he couldn't, and we covered this long ago. Even with a radio telescope 100 times more sensitive than Arecibo, ET wouldn't be able to detect our own radio and TV broadcasts beyond our solar system.

For your argument based on the lack of evidence, you have to assume magic technology. There's no reason to assume it. (ETA: And, as has been explained, the issue is the signal/noise ratio. Once the signal is gone, there's no technology that can "enhance" the noise to bring back the signal--contrary to what you see on TV cop shows that enhance security camera video like this.)

And again, your argument on the timing doesn't help. We are a civilization that hasn't existed for millions of years, and we ourselves haven't made evidence of our existence ubiquitous in the universe. So if you're using the lack of evidence of ETIs to argue that they don't exist, you would also be arguing that we don't exist.

This kind of ET would want to colonize the galaxy if it hasn't already done so.
That doesn't follow at all. And please read again the numbered points I made against your Fermi's Paradox argument. The same stuff applies.
 
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Yes, you are right about time! Even more, I would like to say about frequency band -- our receiver and ETI's transmitter may have not frequency match...

Isn't there an assumption that using the hydrogen line frequency might be a reasonable universal freq that an intelligent, radio-technology-using civilization might use? But yeah--it's another dimension to the astronomical haystack.

Can you answer my other question--is there anything in between broadcast (weak dispersed signals) and the high energy, narrow focus signals you're involved with? Like some medium strength signal that could be aimed at a larger section of the sky (but not omnidirectional)?

I wonder if there might not be a benefit to trying some kind of shotgun approach (rather than using either a hand grenade or a squirrel rifle, by analogy).
 

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