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SETI@Home Publishes Skymap

An anonymous reader writes "The skymap of where in the night sky to find the most promising SETI@Home signals is reported today, along with the research plan for the March Stellar Countdown project. The dedicated use of the Arecibo Telescope to revisit these spikes, pulses, and steady signals, focused on 166 star candidates. Those 166 were pruned from the five billion signals that have been found since 1999, depending on the signal's persistence, closeness to a known star, and frequency. The next step is particularly fascinating, if a signal appears to have increased since the first observation put that star on the checklist."

34 of 317 comments (clear)

  1. Should we be concerned... by bc90021 · · Score: 4, Interesting

    ...that even alien signals so nicely fit a bell curve? Does this mean the search for extra-terrestrial intelligence will be largely disappointing? ;)

    1. Re:Should we be concerned... by Anonymous Coward · · Score: 4, Informative

      I'd like to point out that it's the green/orange squares that are candidate systems. The blue bell curve is the Milky Way distorted because it's an inverse sphere laid onto a square.

    2. Re:Should we be concerned... by Anonymous Coward · · Score: 5, Informative

      actually the "bell curve" effect is the effect of the "plane" of the milky way intersecting with a cylinder (distorted on either end in this projection). The cylinder is "unwrapped" , thus the plane appears as a sinusoid due to the intersection angle of the galactic plane.

      It is also interesting that the radio telscope can only tract objects in a band across the sky, due to physical limitations of a ground based radio telescope. This "can" mean that there are as many as ~4 times as many potential signals out there (since they don't line up with the galactic plane we can assume they are nearby star systems which are scattered about the plane).

  2. Re:"Star candidates"? by mbadolato · · Score: 5, Funny

    Or combine them! Each week we get to vote a new race out of the universe, and at the end, the final two races get married.

    And here's the surprise: the newlywed alien couple will have Disaster Area play at their wedding, and be given their own Heart of Gold Spaceship as a wedding present!!

  3. Re:Proximity to a star? by anakin357 · · Score: 5, Insightful

    The likelyhood of aliens living near a star is probably based on the idea that most lifeforms are somewhat similar to ourselves, and need light/heat from a star to survive.

    --
    If we find aliens I hope they like beer.

    --
    http://www.fsckin.com/
  4. Doppler Drift Rate "chirping" seems way redundant by js7a · · Score: 5, Interesting
    the SETI@home screensaver analyzes the data many times over trying a great variety of possible doppler accelerations. Actually, the screensaver first takes the raw data and mathematically "undoes" a specific doppler acceleration or "chirp". It then feeds the resulting "de-accelerated" data to the FFT (Fast Fourier Transform) routines. This is called "De-chirping" the data. SETI@home tries to do this at many points between -50 Hz/sec to +50 Hz/sec. At the finest frequency resolution of 0.075 Hz we check for 5409 different chirp rates between -10 Hz/sec and +10 Hz/sec!

    -- "About the SETI@Home screensaver

    That seems horribly inefficient!

    Have the SETI people ever heard of cepstral techniques?

    There should be no need to iterate thousands of times over the pattern recognition algorithms when you can just take anouther FFT of the log magnitude spectrum to eliminate doppler shift (the same as what audio engineers would call 'pitch.') Cepstral analysis has been eliminating pitch in audio signal processing for decades. Too bad nobody told the astronomers.

    What a waste of all those CPU cycles!

  5. I have contributed.. by Frank+of+Earth · · Score: 4, Funny

    .. about 14000 hours for the past.. 6-7 years.

    And to think my computer use to just fly toasters when it was idle.

    1. Re:I have contributed.. by seinman · · Score: 4, Funny

      Oh yeah? Well i've done 32,885 hours. Who's on top now?

  6. Will governments allow news to come out? by civilengineer · · Score: 5, Interesting

    Supposing SETI finds something, will the government let out the news to the general public? What about all the historical cases of UFO sightings? Apart from constantly gazing at skies, should we also not try to demand opening up of all classified government documents about any possible UFO sighting?

    --

    New year Resolution: Don't change sig this year
    1. Re: Will governments allow news to come out? by Black+Parrot · · Score: 4, Interesting


      > Supposing SETI finds something, will the government let out the news to the general public?

      Why would governments keep it secret when they could instead use it as a long-distance boogieman to justify increasing defense spending and cracking down on civil liberties?

      --
      Sheesh, evil *and* a jerk. -- Jade
  7. Re:Proximity to a star? by Ptahian · · Score: 5, Insightful

    Because it's more likely than aliens living in the nothingness between stars (a vacuum near absolute zero where atoms per square mile are counted on one hand). Just my guess.

    It's not impossible for something we're only guessing about in the first place, but unlikely given what we believe to be true.

    -ptah

  8. They won't find anything... by sllim · · Score: 4, Insightful

    But there really isn't anything wrong with trying.
    Besides, Seti@home really helped to bring about this idea of 'distributed computing' to the world. And for the science in that end of the project I would be hard pressed to say this project isn't already a success.

    But the more I think about it the more I think that radio signals are not the way we are going to find intelligent beings.
    For one I question if we are capable of picking up the radio signals we are sending out.
    If there was an earth, a duplicate of us, technologicaly, socialy and so forth, say 10 light years away, do we have the ability to pick up it's radio signals?

    And for that matter we have had radio for a very short time, just over 100 years. And our use of it is on the way out already. In another 100 years we will probably be producing a fraction of the radio waves we produce now.

    Any way you look at it the odds are stacked against Seti@home.

    But I still congratulate them on giving us geeks something to talk about.

  9. A little OT but by geeveees · · Score: 5, Interesting

    Why do we always assume that the aliens will be more advanced than us? How do we know we won't be visiting alien planets and abduct its inhabitants? Just a little something to think about...

    --
    I am a viral sig. Please help me spread.
    1. Re:A little OT but by Gorobei · · Score: 5, Interesting

      We assume aliens will do the same exponential technology advance that we are doing.

      If life is common, the vast bulk will be single-cell goop, lichen, etc. The ones that go multi-cellular have a shot at intelligent species. Get intelligent, and you have fire, the wheel, and radio in short order.

      The human race has had radio for 100 years or so: if we detect a signal from aliens, chances are that they have had radio for thousands or millions of years. We are almost certain to be the primitives in this case.

      Interestingly, the radio age is probably extremely short-lived: signal compression, etc, should make any advanced race's radio look like noise to observers.

    2. Re:A little OT but by Dag+Maggot · · Score: 4, Funny

      Well, I for one welcome our new human overlords..
      oh wait...

      --

      I have no pants and I must scream

  10. Re:Proximity to a star? by MuParadigm · · Score: 5, Interesting

    They're assuming that any species capable of producing a radio signal has evolved on in an environment capable of providing the tools to do so. That pretty much leaves: planets.

    Planets, as far our theories go, are generally formed during the creation of stars and seem to generally be captured in orbit around stars. (Of course, I doubt anyone has made a wide search for planets not close to stars.)

    Thus, to look for life, look near stars.

  11. Re:SETI is pointless(repost) by lord_dragonsfyre · · Score: 4, Insightful

    First off, even if we never find life out there, the mere existance of SETI@home helped get the idea of massively distributed computing out there as a viable option.

    Second, I don't think anyone is claiming that radio waves are a viable method of intersteller communication (frankly, all the options there suck, barring the discovery of handwavium or similar magic-tech).

    The point isn't to find a race out there to chat with. The point is to find evidence that, at some point in the past, *someone* out there emitted radio signals. Are they still around? Can we call them up and discuss deep, philosophical questions? Maybe, and probably not. But proving that intelligent life exists or existed off Earth, even if it went extinct long ago by our reckoning, is a worthy enough project, in my less-than-humble opinion.

    James.

    --
    "I have spread my dreams under your feet, Tread softly, because you tread on my dreams." - W. B. Yeats.
  12. Re:SETI is a crock- here's why by gaijin99 · · Score: 4, Insightful
    You know what? These people are a disgrace. They're little more than cultists, and to quote Contact, "Yep, looking for little green men".

    Er, um, you are aware that "Contact" is a work of fiction, right?

    More seriously your post seems ill thought out. Yes, the odds of finding anyting are rather slim, especially considering that our only sensors are inside the sun's area of interference. However you seem to be underestimating the importance of finding evidence of non-human sentience. Carrying on a conversation is nice, don't misunderstand me, but I'd be happy just knowing for sure that we aren't the only ones out here. Sure, the odds are that there's other people in the universe, but I'd like to know for sure.

    The cost is quite low, really, and its spin off effects are already prooving to be of benefit in the short run. The truth is that "pointless" research has paid off time and again. Maybe SETI won't pay off, but the fact is that it might.

    Oddly enough, you didn't mention the single biggest problem facing the SETI program: the likelyhood that use of omnidirectional radio is not long lived. Here on Earth we're already tending to move away from powerful omnidirectional signals. Increasing use of laser, microwave, fiberoptic, etc is slowly killing off true broadcast radio. Some people suspect that within another thrity years or so the only omnidirecitonal broadcasts will be quite weak and short ranged (equivalant to cordless phones).

    Still, even given that, I'd say that the potential benefit of SETI vastly outweighs its miniscule cost. You've got to take chances sometimes...

    --
    "Mission Accomplished" -- George W. Bush May 1, 2003
  13. Re:Proximity to a star? by AceCaseOR · · Score: 5, Insightful

    Well... we're far more likely to find an extra-terrestrial settlement on a planet where it'll still be there (in theory) each time we check, then trying to look for the Battlestar Galactica or the Katana Fleet or whatever.

    --
    Zagreus sits inside your head, Zagreus lives among the dead, Zagreus sees you in your bed and eats you in your sleep.
  14. Re:SETI was not the first distributed project by deglr6328 · · Score: 4, Insightful

    "Oh, and interesting to note that when SETI@home first started up, they ran out of data to process. So you know what they did? They just fed the same data back to clients, over and over and over again, without telling people- acting like they still had new data to process."

    Hello? SETI@home is a scientific endeavour. Accuracy of results matters, and as long as hacking the client to produce false results is possible(always will be), rechecking work units for authenticity by sending them out to more than one client is necessary, duh.

    --
    - "Hear that?! The percolations are imminent! Cease your ingress!"
  15. Re:SETI is pointless(repost) by Monkelectric · · Score: 4, Insightful

    You're mostly right, but you're completley wrong. The fact of the matter is, SETI probably won't find anything like you say, and it will take too long to talk to anyone we do find, but SETI isn't hurting anybody, and it might help. End of story man. I don't see you doing anything to answer the mysteries of the universe.

    --

    Religion is a gateway psychosis. -- Dave Foley

  16. The WOW signal by 198348726583297634 · · Score: 4, Interesting

    I'm surprised nobody has mentioned the WOW signal. read the link..it'll send chills down yer spine!

  17. Re:Doppler Drift Rate "chirping" seems way redunda by js7a · · Score: 4, Insightful
    The way to handle spoofs is to redo the raw data on someone else's (or a lab) machine if it ever looks promising.

    I'm pretty damn sure they could be getting a many thousand times speedup.

    The process is to take a FFT of the log magnitude spectrum, and look for peaks in the cepstral domain instead of periodicities and triplets in the spectral domain. Maybe there is some reason you can't look for gausians that way. Maybe I ought to take this to email and see what the SETI@Home people say.

  18. Other ways by nhavar · · Score: 4, Insightful

    The point is first to get the proof. If we have proof that there's anyone out there and we know where they are (or did) transmit from then we can start looking for more information and in different formats.

    There are a lot of "pointless" projects out there, cold fusion, AI, room temperature superconduction, teleportation, time travel, an end to world hunger, "peace keeping", Battlestar Galactica as visioned by Richard Hatch. Luckily there are still dreamers out there wasting their time and money trying the impossible. Who know's maybe they'll succeed.

    --
    "Do not be swept up in the momentum of mediocrity." - anon
  19. point vs counterpoint by gad_zuki! · · Score: 4, Insightful

    I think you make excellent points, but the other side also has some good points to make too. Me? I'm just glad someone is doing something. Its hardly resource intensive (theyre not tying up aricebo for months and people leave their PCs on anyway) and in many ways it can be seen as baby steps towards *some* understanding of potential alien contact.

    >They don't get much radio time, and they can't cover much of the sky.

    Granted, but that could change tomorrow with funding.

    >Now chances of actually recognizing the signal as intelligent life are unknown

    I wouldn't say that. Primes in binary would be pretty obvious. Even a something trivial that isn't a pulsar but repeats could be seen as meaningful communication i.e. someone is saying "I exist!"

    >Ok, maybe you see it and you recognize it. Can you decode it?

    Even if they cant or if its just numbers, the proof that life exists off our sphere is revolutionary and will change humanity forever. That's something to take seriously even if we don't know what we're being told.

    > Great, someone's actually listening and gets the signal. You've just had the century-long equivalent of the 20 second bar conversation

    I don't think the consensus at SETI or SETI-like projects is to build a conversation. Its about discovery. The proof that intelligent life is abound in the universe, like I mentioned above, is more than justification for the projects.

    I think people with your kinds of criticisms have a very high expectation of a very limited project. That doesn't mean that the project isn't worthwhile or can't deliver goods. It just wont deliver the goods you seem to want - a "telephone" like conversation with aliens. A verified signal is more than enough to bowl the world over. Who knows how it will affect us. Will space exploration get a second boom? Will people take global disarmament more seriously? Will the religious scream bloody murder?

    Who knows. Like I wrote above, its not an expensive project and I hope to see more SETI stuff in the future, especially powerful wholesale transmissions to likely candidates.

  20. cepstral terms by js7a · · Score: 4, Informative
    John W. Tukey ... is of course best known for his (re)invention, with IBM's Jim Cooley, of the fast Fourier transform, (FFT) which changed the topography of digital signal processing (never mind that Gauss had the FFT 150 years earlier). Tukey was also a great wordsmith: he coined the terms bit, byte, software and cepstrum, (the Fourier transform of the logarithm of the Fourier transform). But some of his cookier coinages, like quefrency (for cepstral frequency) and saphe (for cepstral phase) didn't catch on.

    I first heard about the cepstrum from John, which he had invented to distinguish underground nuclear explosions from earth quakes in connection with the US-Soviet test ban negotiations. It became immediately clear to me that the cepstrum was ideally suited for extracting the fundamental frequency (the pitch) from speech signals -- a difficult task for distorted telephone signals. The cepstrum was an ingenious idea and today, 40 years later, it remains the best method for separating long delays (travel times of seismic waves in the earth's mantle or times intervals between the puffs of the human vocal cords) from short-delay and resonance effects (of the human vocal tract).

    -- Memories of John Tukey

    The seminal work coining the terms is:

    B.P. Bogert, M.J. R. Healy and J.W. Tukey, "The Quefrency Alanysis of Time Series for Echoes: Cepstrum, Psuedo-Autocovariance, Cross-cepstrum and Saphe Cracking", in Proceedings of the Symposium on Time Series Analysis, edited by M. Rosenblat, 1963 (New York: Wiley), pp. 209-243.

  21. Re:If the signal has INCREASED? by pizen · · Score: 5, Funny

    Could you imagine if we managed to discover, decode and re-transmist some alien television or radio signal?

    We could all watch Omicron Persei 8's version of Single Female Lawyer.

  22. Re:If the signal has INCREASED? by RestiffBard · · Score: 4, Insightful

    er, if the signal has increased in a year that would tend to show growth. Say when we were listening to them a year ago the only people with cell phones on their planet were rich doctors. A year later the price of alien cell phones has gone down. now more aliens have cell phones. Hence an increase in traffic across the airwaves.

    And an opportunity for T-Mobile to make a killing.

    --
    - /* dead coders leave no comments */
  23. Re:SETI is pointless(repost) by KoalaBear33 · · Score: 4, Insightful

    * Chance of physically intercepting the signal is next to nothing. They don't get much radio time, and they can't cover much of the sky.

    Agreed... but it doesn't hurt to try. Also, don't forget that to develop advanced techniques or better alternatives, one needs to start with the basics. You don't start riding a bicycle without learning how to balance or how to walk. Same thing here. What they are doing may be "primitive" and next to useless but I'm sure some good will come out of it--if not now, in 50 or 100 years ago.

    * Now chances of actually recognizing the signal as intelligent life are unknown. They've got some great theories. Who knows if they're right?

    Intelligence is an overrated word that is used to oppress lower classes. There is no such thing as intelligene--at least when you look at things from a macroscopic scale. The point wouldn't be to find intelligent lifeform--rather it is to find ANY lifeform. Whatever you find may or may not be "intelligent" (for example, if you find aliens that have mastered electromagnetic waves but haven't even figured out how to build a 10 story building, are they "intelligent"?).

    * Ok, maybe you see it and you recognize it. Can you decode it?

    This will be the tough part IMO. Even if you find something, it could take hundreads of years to decode the message. Stanislaw Lem, a Polish sci-fi author who has written many sci-fi novesl (including Solaris), postulates that it will take 100+ years to communicate with an alien (even if the alien made physical contact). Humans can understand each other's language because we made it all up; and we can understand animals because we are animals. The same cannot be said of foreign aliens.

    * Alright, so who cares if you decode it, you FOUND INTELLIGENT LIFE that existed at least several hundred of years ago

    I can't believe you are dismissing this. If contact is made (or evidence is found), it will be the MOST IMPORTANT human event in the last 500 years. It will be bigger than theory of gravity, theory of relativity, development of transistors,computers,electricity, World War II, rise of Communism, Nazism, etc. Discovery of aliens will likely result in elimination of religions (or religious wars), massive scientific "push", etc. It will alter our understanding of the universe. We will know that we are not "alone". In addition, this can provide more answers to the meaning to life and further philosophy...

    * Ok, so you send a reply. You figure out where that source planet will be when the signal finally reaches it. * "The aliens get it" requires the same hurdles. Mainly, they have a SETI program, they've got their ears pointed in the right direction, they identify the reply as intelligent life, etc. Hell, it assumes they haven't nuked themselves into extinction like we're on the steady path towards.

    They may or may not have technology dealing with electromagnetic/radio waves. But the hope is that they will. For all we know, they may be far more advanced in that area... As far as aliens nuking themselves, it is a possibility. However, I don't think it will be the case. Humans are very violent (we kill each other, destroy nature, etc). I think the probability of finding more peaceful beings are higher than finding ones that are more violent than us.

    * Now, lets say they decide to reply(ie, they're not xenophobic, they don't think it's pointless, etc). It takes another couple hundred years to get back to earth, assuming they aim right etc.

    This argument is moot. There will be a massive lag so people can't communicate. However, we (and them) can sort of figure out that something is out there. Also one should keep in mind that this will be a long term action, done to benefit humanity as opposed to the individual. For instance, if you send a signal now, someone 200 years from now may get back the response from the alien. It does not benefit you

    --
    ......The worst thing in my life happened when the stock market started mattering more than the economy
  24. Re:Doppler Drift Rate "chirping" seems way redunda by Skuld-Chan · · Score: 5, Insightful

    What a waste of all those CPU cycles!

    Ahh the very nature of Seti@home.

    After I quit using it my power bill went down over 20$ a month and I'm not kidding in the slightest.

    Before that it struck me - what's the actual probability of finding intelligent life? I work in tech support 90% of all the people I talk to each day are complete morons.

  25. Up in the air by nimblebrain · · Score: 5, Interesting

    I used to think we were simply looking into outer space with the SETI project and hearing complete silence. Well, that doesn't seem to be the case. Even in the 'relatively quiet' radio bands, there's still a whole lot of signal going on, and by and large we can't tell it from noise.

    The article mentioned is a bit humble when saying 'oh yes, there were more than 166 candidates'. Yes, there were a 'few' more, and it was pretty tough to pare the list down to something the Arecibo could be solidly used for, according to the Planetary Society

    Nor is the search in the radio band the be-all end-all to all the observation techniques; to that effect, there are a number of other observations and techniques underway.

    I suppose the "saddest" thing at the moment is that we honestly cannot currently tell the difference between "nobody's out there" and "ten billion civilizations are out there", due to our narrow and infrequent observation bands, our simplifying assumptions, and our limited processing power (think of the difference another 50... or even 10 years will make to that).

    I suppose an additional question we might have to face if we hear an ET signal: how many people will play it backwards and hear Elvis or the Devil?

    --
    Binary geeks can count to 1,023 on their fingers :)
  26. Re:Proximity to a star? by UnknowingFool · · Score: 4, Informative
    The Drake equation computes the number of theoretical civilizations we can possibly contact. The first two factors are heavily dependent on proximity to stars.

    R* is the rate of formation of stars suitable for the development of intelligent life. These stars are neither too hot (too close) nor too cold (too far) for life to form. This happy middle ground is also known as the Goldilocks zone.

    Fp is the fraction of those stars with planets. Planets normally form only around stars. Some solar system have no planets and hence very little chance of having life as we know it.

    All life is dependent on energy is some form or another. For most life on this planet, that energy is the sun in the forms of light and heat. While other forms of energy have been found to sustain life like chemosynthesis in the deep ocean trenches, this phenomenom will be nearly impossible to detect from earth. It is far easier to detect stars, but that doesn't mean locating a signal will be a breeze.

    --
    Well, there's spam egg sausage and spam, that's not got much spam in it.
  27. Link text: my pet peeve by p3d0 · · Score: 5, Informative
    Please don't get too creative with what text you put in your hyperlinks. It makes it hard to tell where the links go. Hint: look at the Related Links box, and if it's totally nonsensical, your links need work.

    Let's look at the links in this article:

    • "skymap" points to the astrobio article
    • "most promising" points to the skymap
    • "project" points to a past slashdot article about SETI@home
    • "these" points to a description of the signals SETI@home looks for
    Here's my suggestion:
    "An Astrobiology Magazine article today presents the skymap of where in the night sky to find the most promising SETI@Home signals, along with the research plan for the March Stellar Countdown project that produced it. The dedicated use of the Arecibo Telescope to revisit the most promising spikes, pulses, and steady signals, focused on 166 star candidates. Those 166 were pruned from the five billion signals that have been found since 1999, depending on the signal's persistence, closeness to a known star, and frequency. The next step is particularly fascinating, if a signal appears to have increased since the first observation put that star on the checklist."
    --
    Patrick Doyle
    I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
  28. Aliens by TrollBridge · · Score: 5, Funny
    Would interstellar aliens be treated the same as illegal aliens? Unless of course they had passports or green cards, the interstellar aliens I mean. And would illegal aliens be jealous of interstellar aliens? And if they (the interstellar aliens) became citizens, they'd no longer still be interstellar OR aliens, right? Would they (illegal aliens) still receive free healthcare and education? Would the interstellar aliens (who became citizens and are no longer interstellar or aliens) have to pay taxes? Wouldn't the until-recently-interstellar-aliens then be upset that illegal aliens don't?

    These are some serious questions that need to be addressed before we invite more aliens into the country, I think.

    --
    There's a Mercedes gap too. I want one and can't afford one, but it's not government's job to do anything about it.