ETs Within 1,000 Light Years?

[Airbrush]

What does your Drake Equation yield? I heard Michio Kaku interviewing a guy working at SETI a couple of weeks ago on his radio program "Explorations". Did anyone catch that? They discussed the likelihood of detecting intelligent signals from nearby stars. The SETI guy, sorry I missed his name, said he didn't know how common intelligent life was, but within the next few decades the SETI search will either find ET(s) or conclude that they are not out there, or at least not transmitting. He was critical of the Rare Earth hypothesis, among other things, explaining how even it Earth had no moon the loose rotational axis would move so slowly that it would hardly pose a threat to early man. He finally and reluctantly gave his current assessment of the Drake Equation and gave his number of ETs, at least as intelligent as we are, as about 10,000 in our galaxy, and probably one within 1,000 light years from us.

[SH3RL0CK]

Well, its all speculation. Depending on how you fill out the unknown variables in the Drake equation, you can pretty much get any answer you want.

 

Of course, the classical answer to the Drake equation is there isn't any other intelligent life - intelligent life is extremely rare. Because if there is intelligent life elsewhere in the universe, why aren't they here already? This is based upon the supposition that there has been more than plenty of time for intelligent life to develop elsewhere (anywhere) in the galaxy and colonize (even if only by generation ships) the entire galaxy, including our solar system.

 

My view on the matter is that there is intelligent life apart from the earth. But that this life is not being permitted (by whoever is in charge) to interfere with the affairs on earth, except in very specific, and non-intrusive ways.

[Moontanman]

If indeed there is one et with in 1000 lights years of us they would not know necessarily know of us yet since we have only been send radio for less than 100 years and detectable signals for even less. Unless they happen to be very close or have been sending a long time we would not know of them either.

[Martin]

...My view on the matter is that there is intelligent life apart from the earth. But that this life is not being permitted (by whoever is in charge) to interfere with the affairs on earth,...

 

These are all three thoughtful stimulating posts---thanks Airbrush, Sherlock, Moontanman. I can see a point to what S. says namely consciousness in its various forms is extremely interesting.

 

If future squirrels developed some mathematics I would be really interested in learning how it compared with human-invented mathematics. If super-evolved parrots happened to discover laws of physics, I would be extremely curious to know if they were the same as Newton's. Or Heisenberg's. But if we had interfered and taught the parrots ours before they discovered their own, then it wouldn't be as fun or valuable.

 

I don't mean just counting acorns, or skillful flying. I mean mathematics on par with ours, but presumably different. How different could it be? Are the laws of physics, the concepts like energy and angular momentum, unique. Does every ETI discover the same set of concepts and laws? Does every ETI have some analog of pythagoras, pi, sine and cosine, calculus? If not what range of variation is possible? I can see that every un-interfered-with consciousness is a uniquely valuable asset, if you desire understanding.

 

So I can see the point of not bothering your neighbors if they seem to be in the process of evolving consciousness---if it was a different kind of consciousness that you thought you could learn something from. Maybe learn something new about the universe by watching alien thought and understanding develop.

 

There would be a self-interest motive not to interfere. Because what does interfering get you? That is worth anything.

 

Goes along with Sherlock's idea.

===================

 

I can't contribute to the basic thread topic though. I have no idea how to estimate the number of ETI species in the galaxy. Or star systems inhabited by ETI critters.

 

Basically it is a Darwinian evolution problem. whatever else life does it evolves to fill niches. Most niches I can think of are suitable for selfreproducing robot life, rather than wet meat. And evo is always doing surprising stuff, and altering and creating new niches. So I don't even trust my intuition about the directions of future evo.

 

Whatever intelligent life evolves to (starting say in watery earthlike planets but then evolving more widely viable forms) it probably is life-forms that can live in vacuum and endure hard radiation and wide temperature range----because there are more environments to live in that are vacuum and exposed to radiation (the kind you have to shield astronauts from, solar flare stuff).

 

So when you go thru the logic steps of the Fermi Issue, you need to have a realistic picture of what widespread or galaxy dominant species are like and what their desiderata are. Which I don't expect they would be interested in watery earth-like planets, except to study. Because they don't need liquid water, or atmospheric pressure, or an ozone layer to block UV, or Kentucky Fried Chicken to eat, or someplace to go to the bathroom, probably. If there are any evolved species in the galaxy, I mean. There might not be any, of course. So but if there are some, Fermi asks "where are they?" and I go "why should they come? why would the earth be of interest except as something to study?"

Edited May 25, 2009 by Martin

[D H]

What does your Drake Equation yield?

My personal take: We are essentially alone. Not all alone; there are 100+ billion galaxies in the universe, after all. However, if our nearest neighbor is over 1000 galaxies away, or even 10 galaxies away, how does that differ in any significant way from being utterly alone in the universe?

 

The key argument against us being alone (or even essentially alone) is the mediocrity principle. My arguments against the mediocrity principle are three-fold:

1. What justifies that principle? It isn't scientific at all. IMHO, the mediocrity principle is yet another example of why the divorce between science and philosophy at the dawn of the scientific age was a very good thing.
   
2. What makes us special? Maybe nothing. What makes the winner of the $100 million lottery jackpot special? Nothing. He just got lucky.
   
3. What makes us special? A lot of things. Multiply a lot of small probabilities together and you get an exceedingly small probability. We got lucky and hit the jackpot.

 

He was critical of the Rare Earth hypothesis, among other things, explaining how even it Earth had no moon the loose rotational axis would move so slowly that it would hardly pose a threat to early man.

The Moon is one of those things that potentially make us special.

 

"... even if Earth had no moon the loose rotational axis would move so slowly that it would hardly pose a threat to early man" is an exceedingly fallacious argument, not one becoming a scientist. Early man would never have arisen if the conjectures about the Moon's role in stabilizing the Earth's rotation are correct. The Earth would instead have suffered the same fate as Venus: A very slow retrograde rotation. Venus didn't suddenly switch from rapid prograde rotation to slow retrograde rotation one million years ago. The transition occurred slowly and gradually over the last 4.5 billion years, with most of the damage done early on in Venus' history.

[CaptainPanic]

If ET has the same attitude as us, we'll never find them:

 

We have a project to search, but we're going to scrap it after less than 1 century.

 

What if ET is just taking a century-long lunch break? What if they only decide to broadcast some message to us once they received a signal from us? We only transmitted the first signal about 1 century ago! Our current signals are a lot of noise from many sources that broadcast on the same frequencies. Do we even know if ET will find us, if he/she/it receives the signals we're creating now?

 

Within the 1000 lightyear area around us, the majority of the civilizations (if there are any) don't even know that WE are intelligent enough for basic space flight and even radio.

[Moontanman]

Our own search efforts are pretty much based on ET trying to be found. We could listen in on leakage from say an earth like civilization only if it was very close.

 

This may be of interest here.

 

http://www.ufoblogger.blogspot.com/2009/05/astrophysicist-discovered-suspicious.html

[Airbrush]

To quote from the excellent story you attached:

 

"The belief that an alien civilisation might also be listening to our television and radio signals has also been dashed by the recent discovery that the signals don't, as once thought, reach into deep space: they eventually become so weak that they disappear in the roar of the electromagnetic noise."

 

Then how far into "deep space" do the SETI team hope to listen?

[Martin]

Sorry for butting in, I just saw something on Colbert Nation. I dont normally follow that but heard he had a guest on who is an author of a book about the ET hunt

 

http://www.colbertnation.com/the-colbert-report-videos/228301/may-20-2009/seth-shostak

 

The book's name is Confessions of an Alien Hunter and the author is S. Shostak.

 

From what the guy said, in the brief interview, especially at the end, it sounded like he didn't expect to find "squishy things" like us, as intelligent life. What he thought most likely he said was "artificial intelligence" in other words machine life.

 

This agrees with what I had suspected from a simple Darwinian evo perspective. Conscious squishy life is like the larval or caterpillar stage and it matures into an adult phase which is conscious machine life. Colbert suggested "robots?" and Shostak said that gave the wrong picture---machine life doesn't have to have arms and legs that look like like anthropomorphic robots. It doesn't have to be made after our vertebrate image.

 

I was surprised to find someone whose career is SETI and is promoting a SETI book who is thinking along those lines. It is the same old technology. He described the big dish antennas, and the kind of artificial signal (not natural noises) they are looking for. Mentioned the movie "Contact" with Jodie Foster, to help the audience picture the kind of work he's involved in.

 

What I wonder is how do people like that get money if they are honest and say they want to eavesdrop on communications between advanced conscious computers. It doesn't sound sexy or appealing or even scary. No Klingons. No blue-skinned babes with nice boobs. How long will the public put up with it on such sterile terms?

Edited May 27, 2009 by Martin

[MM6]

The Drake equation is worthless for making calculations. It's filled with guesses. A hundred different scientists can get 100 different answers. "An equation that means anything means nothing." I think Crichton said that. Or I did. Whatever. I think it's worth is in telling us what we don't know but need to know. Which is actually very useful.

 

As far as SETI, I wouldn't classify it as science. I have a soft spot for their motivation, but it borders on pseudoscience. Why not have a search for Santa Claus or a search for Zeus? The hypothesis is supported by a single data point (life on Earth). More importantly it's not falsifiable.

 

I'm much more confident of bacterial life in our galaxy.

 

Another thought. Why would we want to broadcast ourselves to some spacefaring civilization? Compared to them we're weaklings and sitting ducks. It's too narcisistic for my tastes to think any ETs would be interested in our civilization. Moreover, the mere sight of our puny, discordant "society" would only encourage an enemy to attack.

 

Well it's late and I've probably offended many people. Some here may even work on SETI!

[Martin]

I'm much more confident of bacterial life in our galaxy.

 

Certainly. Extraterrestrial microscopic stuff seems much more likely than spacefaring high tech life. Seems like a no brainer.

.... I've probably offended many people.

 

I doubt you offended anyone here. You didn't say anything very original,

or that I haven't heard often enough, but that's fine. (I don't excel at originality either.)

[MM6]

I doubt you offended anyone here. You didn't say anything very original, or that I haven't heard often enough, but that's fine. (I don't excel at originality either.)

 

It was original for me, it was the first time I've said it or read it! (most of it) So you're involved in the project?

[Airbrush]

As far as SETI, I wouldn't classify it as science. I have a soft spot for their motivation, but it borders on pseudoscience. Why not have a search for Santa Claus or a search for Zeus? The hypothesis is supported by a single data point (life on Earth). More importantly it's not falsifiable.

 

I'm much more confident of bacterial life in our galaxy.

 

Another thought. Why would we want to broadcast ourselves to some spacefaring civilization? Compared to them we're weaklings and sitting ducks. It's too narcisistic for my tastes to think any ETs would be interested in our civilization.

 

I agree that the basic assumption of SETI is that ETIs would have any reason to broadcast their position in space. What would any ETI have to gain by letting the galaxy know "Here we are! Come and do with us what you will."

[Martin]

I agree that the basic assumption of SETI is that ETIs would have any reason to broadcast their position in space...

 

Airbrush, I have to disagree. Isn't SETI simply the search for artificial radio signals (coming from off-world)?

 

In what sense does it "assume" anything?

 

To me checking for artificial signals seems like an obvious commonsense thing to do. Even more basic than scientific research. It is a useful, possibly important, piece of information either way. Are there artificial radio signals from outside solar system? Or are there not? I would like to know. Would not you?

 

I don't think of this as primarily science, although their could be science implications, connections to various sciences, science methods used, as with any technological project. Rather than science (discovering and testing laws of nature) I think of it as simply intelligent behavior. Don't you.

=========================

 

1. I think you and others are confused if you assume fearfulness or paranoia on the part of some ETI. I don't think there is a foregone conclusion. There may be no ETI but if there are they may not consider that they have anything to fear from each other. No scarce resources to compete for, etc.

 

The reality might be violent predatory domineering paranoid battle prone romantic swashbuckly and all that. Stealing watery planets from each other and all that. Or it might not be. In any case, what one wants is to know the social reality of the Milkyway, whatever it turns out to be.

 

Some ETI may have discovered that it is perfectly safe to communicate between parts of their community. That's possible. And they may use radio, if they haven't discovered something superior.

 

2. I think you and others are confused if you think that sending a radio message on a beam from City A to City B automatically gives away the position. Suppose there are ETI in various locations and they are just carrying on their business and they want to beam some data.

 

Maybe they aren't afraid of revealing position but even were they the risk is not prohibitive. When you intercept a beam all that tells you is the direction it is coming from.

 

As an instance, if someday we point an antenna at the Andromeda galaxy (a small fuzz-blob) and happen to receive an artificial signal, all that means is it is coming from somewhere in Andromeda (hundreds of billions of stars).

Probably all it means is that a computer somewhere in Andromeda wanted to talk to a computer somewhere in Milky. And that the first computer didn't reckon it was risky for it to go ahead and talk.

 

You can think of other instances on a more nearby scale involving communication from smaller structures, like the Clouds of Magellan, or within our own spiral arm of Milky.

 

If anybody thinks that life (machine and squishy) could never evolve the ability to communicate by radio beam over a larger distance than 1000 lightyears, then please just scale down my examples to something you find more credible. It's easier to talk in terms of known features like Andromeda.

Edited May 27, 2009 by Martin

[Airbrush]

Consider that SETI is searching for something that may be only accidentally broadcasted into space. Like the example in the movie "Contact" when we decoded a transmission from space and it turned out to be them bouncing back something from Earth a very early TV broadcast of Hitler giving a speech. Once an ETI achieves the ability to send radio or TV signals into space, they soon realize that they have nothing to gain by broadcasting themselves to outer space.

 

I would like SETI to keep looking just in case. I may have the wrong impression of what they are capable of, and what is possible.

[Martin]

I would like SETI to keep looking just in case. I may have the wrong impression of what they are capable of, and what is possible.

 

Me too, on both counts! I think continuing support for listening for artificial signals is a voter issue. Not a science issue.

 

Currently my vote is for continuing to scan the radio spectrum.

 

I have no fixed preconception that I assume about what might produce artificial signal, for what purpose. I don't assume anything remotely like "Contact" scenario or any other scenario. I don't assume alien ETI would want to say "Hello". that is a novelistic plot device. Signal could be sent for reasons we cant imagine or would be a waste of time to speculate about.

The question for now is, are there artificial signals in the radio spectrum or not.

 

We have to have a plan with an "exit strategy". If we build sensitive receivers and make an honest try and don't get anything, then I would hope we figure out some other signal mode and wavelength band to try.

 

I don't think it is science, it is just a commonsense Intelligence operation. It is about being well-informed about one's surroundings.

 

Consider that SETI is searching for something that may be only accidentally broadcasted into space.

 

Really? That is not the impression I got from listening to this guy being interviewed. I got the impression that he was looking for any kind of artificial signal broadcast for any reason.

 

Anything coming down that was not the usual bleep and crackle that quasars and pulsars etc put out by known natural processes. Anything you could identify as not natural. And he stressed repeatability. Somebody else has to be able to look at the same spot and get the same result.

 

Once an ETI achieves the ability to send radio or TV signals into space, they soon realize that they have nothing to gain by broadcasting themselves to outer space.

 

This is a good point! I tend to accept it even though I have no confidence in my ability to "think like an alien".

 

It seems to me, without my being at all knowledgeable, that the most likely thing if we get anything at all is to intercept a message from Party A to Party B.

 

If we listen for a while and don't intercept, the that tells us something. Like maybe they don't use radio. Maybe they use lasers. Or there are no ETI. Or they don't communicate over long distance. Lots of possibilities.

 

I wonder if the SETI people have a list of other communication channels besides radio that they think are possible. Might be interesting to see what theyve thought of.

 

Anyway I don't have a scenario in mind. I just want to know are there artifical signals.

[Moontanman]

Lasers are being looked for

[Martin]

Lasers are being looked for

 

Good! Then I vote for continuing that too for the time being.

We need to do a reasonably thorough job.

 

BTW my basic political premise here is what I'd call "astrodemocrat".

I aspire that humanity should voluntarily cooperate to establish squishy life on a few earth-like planets.

 

Some political slogan like "extend evolution to the stars by democratic means"

 

That means that even though I consider finding terrestrial planets and planting our kind of life on them to be maybe the greatest goal or purpose of our species, still I would not support a dictatorial government that compelled humans to pursue this goal.

 

So in a sense I don't care whether artificial radio/laser signals are there or not. We should know whether or not they are, so we should check. But regardless of what we find or don't find, we should work democratically and cooperatively to plant life on some earth-like planets.

 

That is what I mean by "astrodemocrat premise". It is a basic value stance that goes beyond science.

 

One has to distinguish clearly. SETI-business already goes beyond science. It involves political will, decisions, values. And likewise an astrodemocrat orientation does too.

For example I would favor a nonviolent campaign to reduce world population because I think that woud increase our chances of achieving the goal of spreading our kind of life. Also I would favor developing intelligent machines able to do the planting and nurturing of whatever pioneer organisms. I don't expect the remote work to be done directly by humans because they don't live long enough and have very complicated lifesupport. More efficient to send machines to plant the seeds and hatch the eggs etc. Population reduction and developing intelligent pioneer machines are not scientific goals. They are political/ethical goals.

 

To me this is a lot more interesting than SETI. And it puts SETI in perspective. but I don't knock SETI because it seems simple obvious common sense that you need to check what else is there.

Edited May 28, 2009 by Martin

[Arch2008]

This should clarify some questions that have been posted.

http://www.seti.org/Page.aspx?pid=558#a1

Ragbir Bhathal is looking for possible ET signals from lasers as part of the Australian search effort, but the SETI in the U.S. is not yet. The original effort was formed on the premise that an ETI would want to be heard. Hopefully, their engineers would know as we do that the EM spectrum is quite noisy and they would also know that the band around the range 1,000 MHz to 3,000 MHz, with a frequency resolution of 1 Hz is relatively quiet and would be the best candidate for sending a signal. Any accidental signals from their entertainment/information industry would be too weak for most receivers, as would our own. Only after the intended signal was discovered, could funding for an antenna array to actually receive intelligible discourse be constructed. So right now we would only be able to receive a “Wow” type repeating beep, not an actual message.

Intelligent observation is what science is all about. NASA is looking for signs of life on Mars and SETI is looking for signs of technological life somewhere else in our galaxy. Just as there were parameters set on what NASA would look for on Mars, so the Drake equation sets parameters on what might be pertinent to SETI’s search.

That said, our species has been around for about two hundred millennia and two hundred millennia from now we could easily have colonized the entire galaxy. The Milky Way formed billions of years ago, and yet there is not one single pan-galactic ETI, because their Dyson Sphere would be right here.

“Wow”

My Drake equation still yields one.

[Airbrush]

To paraphrase an earlier quote: "TV and radio signals don't reach very deep space, but at a distance they become so weak that they disappear in the roar of the electromagnetic noise."

 

My question still stands. How far into space does SETI hope to be able to detect a narrow-band signal? Of course, laser detection would catch more distant signals.

 

My other questions: Does SETI send a signal outward, so ETI can know about us? How far out do OUR unintentional radio and TV signals reach into space for ETI's to hear us?

 

Are 100% of all UFOs simply mistake, delusion, or fraud?

Edited May 28, 2009 by Airbrush

[Martin]

If by SETI you mean just the activities of the SETI institute then I haven't understood the question. What I mean by SETI is collectively the whole effort of listening for artificial signals (evidence of ETI).

 

Arch has a source from the SETI institute that covers some other activities besides their own, and mentions a 1974 instance of transmission

==quote==

Who else is carrying out searches?

Astronomers from the University of California, Berkeley, are carrying out a search called SERENDIP IV at the Arecibo Observatory in Puerto Rico. About 3% of these data are made available for processing by the popular SETI@home screen saver software. The Planetary Society, an independent, privately funded organization, operated Project BETA at Harvard University (this search was stopped in 1999 due to damage to the telescope in a wind storm) and in Argentina. Ohio State University conducted a full-time search with a large volunteer effort for 24 years; however, this search ended in 1997 when the university shut down the radio telescope they used.

New optical SETI programs are being conducted at the Univ. of California Berkeley's Leuschner Observatory and at Harvard University.

Other radio searches are underway in Australia (see links to the SETI Australia Centre) and Italy. Additional SETI experiments, on a smaller scale, have been, and continue to be, conducted by individual scientists and radio amateurs in the United States and other countries.

==endquote==

I don't know what the Berkeley/Harvard "optical programs" are. They might be looking for laser signals, which would be interesting to hear about.

 

Does SETI send a signal outward, so ETI can know about us? How far out do OUR unintentional radio and TV signals reach into space for ETI's to hear us?

 

Are we also sending any signals?

 

...SETI researchers have not been very interested in broadcasting... Nonetheless, a few, mostly symbolic, intentional messages have been sent. One message, transmitted in 1974 from the Arecibo Observatory, was a simple picture describing our solar system, the compounds important for life, the structure of the DNA molecule, and the form of a human being. The message was transmitted in the direction of the globular star cluster M13, about 25,000 light years away.

 

Personally I have no interest in transmission, but if a political decision were made to transmit then the kind of thing they did is technically smart. Focus on a small target containing a lot of stars, like a globular cluster. That way you can focus a tight beam and put a lot of energy in, and still have a lot of potential listeners. this is not science, it is politics, and of course there is a risk (which I reckon is very slight) of hostile reception. Transmission ought to be a collective political decision, if it is ever done again.

 

 

My question still stands. How far into space does SETI hope to be able to detect a narrow-band signal? Of course, laser detection would catch more distant signals.

 

The question is not well-posed. Who "hopes"? If you mean SETI the institute? They probably have official policy statements that give estimates of that sort. But what I mean by SETI is the whole collective activity of listening for signals, and an activity does not "hope".

 

One can make a rough estimate of a plausible figure. Presumably the folks at Areicibo did their calculations and could reasonably expect that if they used a transmitter antenna the size of the Areicibo dish and aimed a tight beam at M13 then the folks in M13, 25,000 lightyears away, any who were listening with decent gear, would get it.

 

There is no clear answer to such a vague question since it depends so much on how the listener is equipped. There are a lot of stars in M13 though. And it is a tiny tiny blob, so you can focus tight and bear down. It may have been dumb to transmit in the first place, but they did it technically smart IMHO.

 

Are 100% of all UFOs simply mistake, delusion, or fraud?

 

I'm not an expert on UFOs. As far as I know there have never been any convincing reports of ETI "Visitors" and no substantiated material evidence of past "Visits" has ever been found. What there is is silly books of garbage put out for the popular media. But I love Men in Black. I identify with Tommy Lee Jones and Will Smith, the good guys, not with that Evil Cockroach, although his character is kind of cool too. Rip Torn isn't bad either.

 

Here's stuff on M13. http://en.wikipedia.org/wiki/Messier_13

It has hundreds of thousands of stars in a cluster only 145 lightyears wide, and is at a distance of 25,000 lightyears, so the angle is real small.

 

Here's a good technical paper on optical SETI

http://seti.harvard.edu/oseti/oseti_apj_preprint.pdf'>http://seti.harvard.edu/oseti/oseti_apj_preprint.pdf

one of the links in this list:

http://seti.harvard.edu/oseti/

 

Both Harvard and Princeton have optical SETI programs. Maybe it is time to wind down the radio search and get into optical. In the article they give the arguements and trade-offs.

Edited May 29, 2009 by Martin