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Space Science

Interview With a SETI Astronomer 83

Siduri writes "We at Pigdog Journal conducted an interview with SETI astronomer Seth Shostak, and I think it's pretty interesting. He talks about the technical details behind what SETI and SETI@home do (the two programs are very different), and he speculates about the nature of alien intelligence. He's also quite funny."
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Interview With a SETI Astronomer

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  • ...we should first find intellgent life forms here on earth =]
  • See also... (Score:3, Informative)

    by igaborf ( 69869 ) on Saturday December 22, 2001 @10:11AM (#2741274)
    Tune in the Universe [arrl.org] -- Amateur Radio and the Search for Extraterrestrial Intelligence
  • Drake? (Score:5, Informative)

    by Wire Tap ( 61370 ) <frisina AT atlanticbb DOT net> on Saturday December 22, 2001 @10:17AM (#2741286)
    I read through (most) of the article (I just could not bear with all that "Well, you know..." so I didn't finish the whole thing, but I was suprised to not read about FRANK DRAKE and the DRAKE EQUATION. The Drake Equation is arguably the underlying force being the entire aim of SETI.

    And, nicely pasted from E2, here is a good idea of what it is:

    An equation used to estimate the number of technological civilizations that may exist in the galaxy. There is no exact answer to Frank Drake's famous equation, but it nonetheless a tool for the scientific community, and the force "behind every project at the SETI Institute."
    N = R* x fp x ne x fl x fi x fc x L

    Where:

    N = The number of civilizations in the Milky Way whose radio emissions are detectable.

    R* = The rate of formation of stars with a large enough "habitable zone" and long enough lifetime to be suitable for the development of intelligent life.

    fp = The fraction of Sun-like stars with planets is currently unknown, but evidence indicates that planetary systems may be common for stars like the Sun.

    ne = Number of earths per planetary system. All stars have a habitable zone where a planet would be able to maintain a temperature that would allow liquid water. A planet in the habitable zone could have the basic conditions for life as we know it.

    fl = The fraction of those planets where life develops. Although a planet orbits in the habitable zone of a suitable star, other factors are necessary for life to arise. Thus, only a fraction of suitable planets will actually develop life.

    fi = The fraction life sites where intelligence develops. Life on Earth began over 3.5 billion years ago. Intelligence took a long time to develop. On other life-bearing planets it may happen faster, it may take longer, or it may not develop at all.

    fc = The fraction of planets where technology develops. The fraction of planets with intelligent life that develop technological civilizations, i.e., technology that releases detectable signs of their existence into space.

    L = The length of time that communicative civilizations release detectable signals into space.
    • "I didn't finish the whole thing, but I was suprised to not read about FRANK DRAKE and the DRAKE EQUATION."

      Get your paws off me, you damn dirty karma whore :)

      Frank Drake actually shows up, but his last name isn't used. Seth couldn't be talking about anyone else; this would be Project Ozma:

      "When Frank did the first experiment in 1960, that's the way it was done. He just had a little motor that essentially turned the knob on the receiver and turned it up and down the dial, very slowly, you see, so the frequency was changing. And you could just look at the output. And he had a loudspeaker connected to it."

      • Yeah yeah, everyone needs a boost now and again.

        I had the opprotunity to do some research at the Green Bank Radio Observatory last December(woo! dish time!), and while I was there, I saw Drake's original receiver. It is just a monument now, on the right side of the entrance, but it is still inspirational. One could only imagine the ensuing watershed that would result in alien contact, and to think that it started with (in the modern sense of searching) that little array of antennas is simply awe-inspiring.
    • Re:Drake? (Score:2, Interesting)

      The equation makes alot of sence, but the only thing that Drake takes for granted is that all life is based on life here on Earth. Given that we dont have anything else to compare it to, but still. Don't you think thats a really basic generalization of how life works. I for one dont think we should be basing the creation of life everywhere in the galaxy with realtion to the way life was created here on earth. It would be pretty arrogant to think that way. For all we know, it could be the exact opposite everywhere else and we are the exception. But then again, I could be wrong.
      • If there are other ways that intelligent life can develop, that just means there would be more intelligent life in the universe than this equation predicts.
    • Whilst the Drake Equation is important, it's certainly not "the underlying force [behind] the entire aim of SETI", and not as important as Drake's other work, from Ozma onwards. [seti.org]

      The Drake Equation was simply an effort to provide a standard focus for discussion of the probabilities of receiving a signal from extraterrestrial civilisation.

    • Actually, the Drake equation is useless to calculate how many civilizations are in the Galaxy, simply because many of its parameters are unknown.

      It's mainly intended as a framework for discussions about SETI topics.
    • There is no exact answer to Frank Drake's famous equation,

      That is somewhat of an understatement. For most of those numbers, we simply haven't the faintest clue. How many real experts, for instance, do you think we have on "The fraction of planets with intelligent life that develop technological civilizations"

      but it nonetheless a tool for the scientific community

      Not really, as it makes no predictions at all except "once you have studied and done statistical anysysis on a large number of solar systems, inhabited and not inhabited, you will be in a position to estimate how many of them are inhabited" Well, Duh!

      The Drake Equation's only use is to underscore just how ignorant we are of so many factors that might determine what's out there.

  • Seth Shostak:...turns out the Ringworld's a little unstable...

    Thanks for that. After all the rumors, I think we deserved to be told officially.

  • putting a chip in my brain would be like putting an engine in a horse

    "You might get a faster horse, but why bother with the horse part? Why not get rid of the horse altogether and replace it with a Ferrari? I mean, really?"

    I still want my brain chip!!!!
  • The Search for Extra-Terrestrial Intelligence (SETI) will most likely discover either biology-based intelligence like our own, or an advanced form of machine-based Artificial Intelligence. [sourceforge.net]

    Alien civilizations conducting a similar search in the near future are likewise likely to find either us humans or the AI mind-species that succeeds us in the onwards march of Technological Singularity. [caltech.edu]

    Along the lines of the SETI@home project. there is also a kind of AI@Home project to the extent that independent AI programmers have been creating Visual Basic Mind.VB [virtualentity.com] and Java-based Mind.JAVA AI. [angelfire.com]

    Whether we find Extra-Terrestrial Intelligence [msatech.com] or not has a bearing on the Theology [sourceforge.net] of Artificial Intelligence, [sourceforge.net] because if we find that we are not alone in the universe, we will have to re-think our ideas on our relationship to our Creator.



    • Why would we want to find alien life in the universe?

      Say we did find aliens. Then what? First no scientist would ever believe we actually found it. You'd have a situation where the world is flat instead of round because people see its flat.

      So say you did prove somehow (if thats possible) that theres alien life via some radio signal, then what?

      People never even stop to think what comes next if Seti ever did find alien life in the universe.

      However I dont think Seti ever will and think its a waste of money, and if they ever did i dont think people would believe it because theres no way to prove it really is from an alien source and not something else.
      • You seem to be confused about what a scientist is.

        If we found PROOF of aliens, all scientists would believe it. Now, getting an apparently intelligent radio signal may not be enough proof, but if we do get some good proof, of course, scientists will believe it. That's what it means to be a scientist - you look at the facts and not just your beliefs.

        Moving the Earth from the centre of the universe to a minor speck around a minor star has actually had an affect on certain mainstream religions, societies attitude towards science, and other 'minor' changes. I'm sure proving that there are aliens will have a similar affect.

        The idea that everything that doesn't make a profit is a waste of money will, I'm sure, be the United States downfall.


        • Just like they didnt believe the world was round in the past.

          You see, its very difficult to prove stuff like this, we've gotten rocks with bacteria in it from mars, we see proof of water on mars and other planets, how much more proof do we really need? WE even have people on earth claiming they see UFOs and Aliens, crop circles and so on and so forth.

          With the proof we have, scientists dont believe it. ITs going to take more than some sound waves from the sky to prove aliens exsist, they will have to land in front of the white house on multiple TV stations in front of millions of people, and people will have to go see it in person because they still wont believe it. (could be a hoax, people can manipulate the images, etc etc)

          Its going to take, ALOT of proof, not alittle, to convince scientists. And I think that proof will be actually seeing an alien in person and studying it.
  • I thought the point of writing up an interview was to isolate the interesting information from all the [sigh] and [mumbles] and "well..." and " I think [uhm] maybe - well, if you look at it like this, it might be.."

    Why was this terrible writeup ever posted? I couldn't bear to read more than half of it...
  • What is interesting is that we may be looking for the Wrong Stuff;

    if you look at the kind of signals that we're currently using, sort of spread-spectrum signals and things like that, they're very complicated, and they're completely unlike the kind of things we look for in SETI. The kind of things we look for in SETI are signals that are just what are called narrow-band signals, that are on one spot on the radio dial. [...] The advantage of that is that it makes it really easy to find the signal because all the energy is in a small band so it really stands out as a big spike of energy. Whereas if you spread it out over five megahertz, like a TV signal, then the energy's spread all over the band and it's very hard to find. But on the other hand, the actual signals that we use are spread out, more and more. And ET will be at least as advanced as we are, so you might say, "Well, why would they make those narrow-band signals?" And the answer is, probably: most of the time, they don't. [...] (but) there's lots of things that would have narrow-band components in the signal. So that's what we look for

    Let's face it, if EM transmission goes the way of the Napoleonic Semaphore system [deadmedia.org], then we will not have a chance to intercept the new technology.

    • Maybe ANY advanced civilisation uses quantum encryption / communication for everything. This means that any communication has one sender and only one reciever. Any "listening in" by a third party like SETI will only get White Noise.
    • I've been saying that for a while. [slashdot.org] Everything SETI@Home could find is legacy radio technology. The FCC wouldn't allow the startup of a new service with significant energy in the carrier today; it wastes spectrum space.

      Early radio was about 80% carrier and about 20% content. (Broadcast TV still is.) Any signal that doesn't look like noise at first glance is grossly inefficient. (Listen to modems to get this.) Modern radio signals, like spread-spectrum cell phones, digital radio, and broadcast HDTV, only have a few percent overhead. And so they look like noise.

      Nevertheless, almost all useful radio signals have some redundancy, for synchronization, framing, or error correction. There's stuff to look for.

      The problem is that you need a receivable signal, with a signal/noise ratio good enough that you could potentially extract the content, just to find a modern signal. It's possible to detect much weaker carriers than you can demodulate, by averaging over a large number of cycles. That's why SETI tends to look for carriers.

      Looking for carriers made sense at first, but now that the whole sky has been searched repeatedly for carriers with no finds, it's clear that nobody is blasting a carrier at us. So here's where SETI is today:

      An old joke had it that the drunk searched for his lost keys not where they were dropped, but rather in the yellow circle of a nearby lamppost. Upon being questioned about the logic, he offered the compelling response - he searched where the light was better.



    • And this is something we never even consider.

      Why the hell would they be using radio when they have nano technology, and mind to mind communication via some more efficient technology via lasers, or Electro magnetic type technology, really why would they be using radio if they've been around for millions of years before us when we are using radio after not even a million years of being around.


  • It would have been interesting get Seth's reaction to the growing rumors surrounding the discovery of a signal coming from EQ Pegasus a year or so ago.

    For those who don't know what i'm talking about, the scientific comunity has been argueing about the "discovery" of an extraterrestrial signal comming from EQ Pegasus, a small binary system situated about 27 lightyears from Earth.

    The signal capted by Paul Dore with a small radio-telescope was distributed to several observatories for analysis. Astronomers don't really know what to think about it. A press conference was scheduled, but it was cancelled due to threats from an unnamed source. There are rumors the Air Force was involved in silencing the guy who found it, starting some suspicion that it could have been a deep space probe, a CIA "Black" project, or similar. The signal would have been capted the October 22 & 23, which is some weeks after a powerfull Radio-Telescope from Arecibo would have picked a strange signal comming from EQ Pegasus in a project called Phoenix. Astronomers had concluded that it was just interference coming from a geosynchronous satellite.

    The SETI program tried in vain to pick up the signal, and they said that this was either a big joke, or interference.

    Makes you wonder.

    Cheers,
  • by Anonymous Coward
    This interview, brilliantly transcribed as it is, hardly does Seth Shostak justice. The man, quite frankly, is freaking hilarious.

    And you, too, can see him, without annoying pigdog interviewers, at the 55th annual Conference on World Affairs, held in Boulder, CO, April 8-12, 2002.

    Watching this guy tear into the hardcore UFO nuts here in Boulder is highly entertaining...
  • seti is bunk (Score:1, Interesting)

    by yulek ( 202118 )
    seti is bunk [epinions.com] (article i posted on epinions a year ago)
    • I agree with much of your analysis about the psychological reasons for the popularity of SETI@Home. A lot of people probably run the program because they've read a lot of sci-fi, or watched the X-Files. Some of your criticisms of the likelihood of discovering other intelligent life are also valid, and discussing the relative merits of SETI@Home vs weather modeling and protein folding is a tarpit I'm not willing to climb into today.

      But in the end, your review relies heavily on claims that you cannot possibly know to be true.

      "seti@home makes a lot of assumptions in order to make it's goals seems plausible. . ."


      No. SETI researchers make no such assumptions. They certainly don't make many of the assumptions you've claimed they make. For example, you say that one of SETI's assumptions is that every planet that develops life will eventually develop an intelligent civilization. I know of no serious researchers who assume such a thing. In fact, the URL you listed to demonstrate this assumption says precisely the opposite.

      You correctly claim that our own evolutionary history would indicate that intelligence such as ours is probably an unlikely development. But you incorrectly claim that "intelligence itself is not evolutionarily stable." We only have a very few examples of intelligence, and not enough to make such a statement. Sure, brains are expensive, but judging from the success of mammals, they're a valuable investment. The only way to know for sure would be to look at the evolutionary paths of thousands of worlds, and compare them.

      The rest of your review is based on several other unprovable assumptions:

      - That the civilization will not invest the time or resources in contacting other worlds.

      - That the energy requirements of a long-term project would be prohibitive.

      - That most civilizations will self-destruct within a few centuries.

      As to the first two, we don't know what energy technologies will be developed in the future, how committed a civilization might be to finding others, or how good a very advanced civilization would be at picking candidate planets to beam signals at.

      For the third, I would dispute your claim that "We have come close to wiping ourselves out several times already." Even in the event of a full nuclear exchange, the extinction of the human race would not be guaranteed (please see the scientific simulation, Fallout [interplay.com] for further information). We could certainly survive if a major city was nuked every decade or so. In short, I think the long term survivability of the human race is higher than you claim. More importantly, since we have no prior data, you have a rather flimsy basis for making these claims.

      This is part of what makes SETI research so valuable. Finding out how common other intelligence in the universe is tells us a lot about our own situation. Even if we did a complete, thorough search of the entire EM spectrum for ten thousand years and came up with nothing, we'd still have learned something valuable. We'd have learned that successful, intelligent species are very few and far between, and that it was even more important that we not screw things up.
      • "seti@home makes a lot of assumptions in order to make it's goals seems plausible. . ."

        No. SETI researchers make no such assumptions. They certainly don't make many of the assumptions you've claimed they make. For example, you say that one of SETI's assumptions is that every planet that develops life will eventually develop an intelligent civilization. I know of no serious researchers who assume such a thing. In fact, the URL you listed to demonstrate this assumption says precisely the opposite.

        no, i really think you need to reread this [berkeley.edu]. they specifically say that a planet that spawns life will evolve intelligence 100% of the time. to me that's utter bunk. they plug rediculous values in drake's equation's variables.

        You correctly claim that our own evolutionary history would indicate that intelligence such as ours is probably an unlikely development. But you incorrectly claim that "intelligence itself is not evolutionarily stable." We only have a very few examples of intelligence, and not enough to make such a statement. Sure, brains are expensive, but judging from the success of mammals, they're a valuable investment. The only way to know for sure would be to look at the evolutionary paths of thousands of worlds, and compare them.

        this is what i meant by a some very well timed random events. without them, mammals would not have been given the opportunity to evolve. mammals didn't evolve brains because they could, they did it because they had to due to the particular ecological pressures present. had those ecological pressures NOT been present, there were much better mechanisms to spend "energy" on.

        The rest of your review is based on several other unprovable assumptions:

        - That the civilization will not invest the time or resources in contacting other worlds.

        SETI always uses us (earth) as an example. so i'm doing the same. how much have we done to contact other worlds? what if all the other intelligences are ALSO just listening?

        - That the energy requirements of a long-term project would be prohibitive.

        how is that unprovable? we're looking for radio signals. we know what energy costs it takes to send multidirectional radio signals for huge distances (astronomical).

        As to the first two, we don't know what energy technologies will be developed in the future, how committed a civilization might be to finding others, or how good a very advanced civilization would be at picking candidate planets to beam signals at.

        yeah but come on, radio communications is a PRIMITIVE and energy INEFFICIENT technology. by the time future energy technologies are developed radio waves might not even be used.

        - That most civilizations will self-destruct within a few centuries.

        For the third, I would dispute your claim that "We have come close to wiping ourselves out several times already." [discussion of nuclear war's effect on our survival]

        i admit my statement is a cynical one, however we have to admit things look pretty bleak! and self-destruction doesn't have to mean nuclear war! there's plague, nano-technology, chemical weapons, ecological disasters, and a score of destructive ways we'll develop in the next 50 years.

        This is part of what makes SETI research so valuable. Finding out how common other intelligence in the universe is tells us a lot about our own situation. Even if we did a complete, thorough search of the entire EM spectrum for ten thousand years and came up with nothing, we'd still have learned something valuable. We'd have learned that successful, intelligent species are very few and far between, and that it was even more important that we not screw things up.

        i suppose. or that they are not willing to talk to us. or that we missed a critical segment of the sky. or that our algorithm had a bug in it (remember when SETI was sending the same block to every computer for a few weeks?). or that we're the only ones stupid enough to use EM in the first place (what if all the other intelligent beings use ESP?)...

    • goddamit, why the hell did someone metamod this to "overrated". did you even bother following the link i posted?

      i swear to god, slashdot is becoming impossible to post to, there's a small community of posters who automatically get a 2, and hardly anyone else can get a friggin voice.

      i think the article i link to is very interesting and worthy of discussion...
  • by Freshman ( 9729 )

    Here's an another online chat/interview from 2 years ago conducted by ABCNews.com with the same guy.

    A Chat with Seth Shostak: Listening for E.T. [go.com]


  • We all know Seti is a complete waste of resources, why not have an article talking about how to cure aids or cancer with distributed computing?
  • Seth has a very important point.

    "...they look for Dyson spheres by looking for stars that have a lot of infrared. But you know, they've only looked a couple hundred stars."

    "..So that was 1959 and by 1960 people were already looking for the signals."

    "...So if you want to send a bit of information from here to Alpha Centauri it's cheaper, in terms of the energy, to do that with radio than to do it with light."

    "So, you know, that's been the argument for many years. Now that argument isn't very solid anymore. "

    That's a very insightful statement. Perhaps we are yet to discover yet another means of efficient mode of communication. Now suppose Earth were to try and make contact with another civilization, would we use smoke signals or radio?

    Just imagine what would have happened if someone had transmitted a radio message just about 200 years ago? We do not even know if someone did.

    Perhaps it is possible that some alien civilization has a much more efficient and better means of communication, and they are trying very hard to tell us something, but hey, would we know it even if we saw it?

    Perhaps they should try blowing up stars next or something ;-)


    • Or Aliens could figure we arent worth the time in paying attention to. Kinda like we dont pay attention to ants.
    • Perhaps they should try blowing up stars next or something ;-)


      That might be a rather extreme way to go about it. :) Besides, what would they assume was being communicated? I don't think there's any natural way for a star to blow up in the middle of it's life cycle. But if they know something we don't, they may just assume something perfectly natural happened. 'Twould be a waste of a good sun in any case.

      Now, in a similar vein, I once heard an interesting concept in interstellar communication: Just dump a few tons of tritium (or some other artificial isotope) into the sun's atmosphere. The emission spectrum given off by the material would show up on any spectrography equipment they might have pointed our way.
      • Actually, you do not even have to go that far. It is more than enough if you can direct a few hundred kgs of any isotope with a small half-life to the sun, when you have solar storms.

        This would automatically cause wierd spectra. But the sad thing is that Chandra (the telescope) recently spotted real astronomical bodies which give out such spectra. So, even this maynot be a sure fire way of letting them ppl know our presence.
  • As Seth points out in the interview, an alien civilization may be using spread spectrum radio broadcasts instead of the relatively easier to detect narrowband transmissions, they may well be using non-radio EM or even a kind of communication outside of our current knowledge of physics - an Einstein-Rosen bridge or something even more exotic.

    But as he says, we can't wait for some new kind of physics. What we have NOW for picking up signals from other starsystems is a bunch of radio telescopes and as far as we know the most likely kind of signal to look for is either a deliberate "here we are" kind of message or "leaked" stuff like our TV broadcasts that have strong carrier signals. Sure that leaves out a hell of a lot of potential signals to look for but SETI has a very limited budget - Colgate probably spends more a week marketing toothbrushes than SETI uses in a year - so they have to look for the most likely candidate with the resources they have.

    As new tech become available to then such as the 1hT array in a few years they can widen the search from hundreds of stars to millions. If there is only one civilization in that search group that was broadcasting back when the light we see left their sun then there's a good chance we'll hear them.

    What gets me though is that given the lifespan of the galaxy there's time enough for millions of technological civilizations to arise - but *not all at the same time*. It could be that there's only ever one or two radio capable species alive in the whole galaxy at any given time. Even if there are hundreds or thousands of civizations active right now each is trapped at the bottom of a relativistic-well: there could be a bunch of guys with tentacles a hundred lightyears away sending us a "hullloooo? HELLoooooo??" message *right now* but it'll be a hundred years before we get it. Shit, Alpha Centuri could have been beaming out "pings" for fifty years but gave up 4.35 years and one day before Marconi built the first radio. But coinidences do happen, and they are more likely when playing the odds so I am still caustiously optimistic.

    Given all of this, as is pointed out in the interview, maybe what we should be looking for is not something transient like a radio broadcast or a laser pulse - but examples of stellar engineering that would be evident for millions or billions of years, Dyson Spheres or something. Though to my mind any civilization that can build a Dyson Sphere has probably discovered an energy source a lot better than solar - zero point energy or something, so there may not be a hell of a lot of Dyson Spehere out there.

  • I think I've posted this before, but I'll post it again.

    I've long believed there are ETs out there for us to meet, but the truth is, if they're out there, I doubt highly that they're in our galaxy, which pretty much puts them entirely out of reach for any sort of contact, communication or otherwise.

    I'm not going to post the link again 'cause I'm tired of posting it, but Scientific American ran a great article about 2 years ago about the chances for intelligent (and exploring) life in our galaxy, and the result is, if they existed, they would have colonized the entire galaxy by now. At least, statistics agree with that, and I believe in statistics.

    At only a bit ahead of our current technology, it would only take 5 million years to colonize the entire galaxy, a blink of the eye in astronomical terms. Therefore, we're here, and nobody else has colonized. If they had, their fingerprints would be everywhere.

    Nobody is more disappointed than I by this. I want to meet the ETs, but frankly, I just can't reasonably believe that they're there anymore (at least not in our galaxy).

    There are also compelling arguments about the series of events that led to multi-cellular life and later intelligence on our own planet. Many of these were "accidents" or "luck".

    You add to all this that the fact that every extrasolar system (save one), where we have found planets, they have gas giants in the "habitable zone", or between the "habitable zone" and the star ,which means that no liveable planets could survive (the gas giants would toss them into the star, or more likely, out of the system).

    Hate to be the bearer of bad news, but I think we're alone in this galaxy (with the exception of life that either has no interest in exploring, or a lesser intelligence than us).

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