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Space Science

SETI@Home Publishes Skymap 317

Posted by michael
from the long-distance-call dept.
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."
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SETI@Home Publishes Skymap

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  • by bc90021 (43730) * <bc90021@NoSpam.bc90021.net> on Saturday July 26, 2003 @11:15PM (#6542908) Homepage
    ...that even alien signals so nicely fit a bell curve? Does this mean the search for extra-terrestrial intelligence will be largely disappointing? ;)
    • the signals are not sent that way, its a side effect of the scanning beam.
    • by Anonymous Coward on Saturday July 26, 2003 @11:35PM (#6542988)
      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.
    • by Anonymous Coward on Sunday July 27, 2003 @12:02AM (#6543084)
      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).
      • by ipsuid (568665) <ipsuid@yahoo.com> on Sunday July 27, 2003 @08:29AM (#6543966) Journal

        uhh... no.

        The Arecibo radio telescope is a fixed dish, which rotates along with the Earth. As the beam of the dish passes a constant power signal source in the sky, the power of the received signal will increase, peak, and decrease following a gaussian profile.

        You are correct in the limitations of the dish, however. By pointing the detectors at different places on the dish, the beam can be moved in relation to the plane of the Earth's rotation. The Seti@Home equipment at Arecibo is capable of tracking +1 to +35 degrees declination, and has a beam width of 0.1 degrees. Thus it is only able to see 28% of the sky.

        Seti@Home Whitepaper [berkeley.edu]

  • by AntiOrganic (650691) on Saturday July 26, 2003 @11:16PM (#6542913) Homepage
    Sounds more like it's involved with a new crap reality show than SETI@Home.
    • by mbadolato (105588) on Saturday July 26, 2003 @11:20PM (#6542929)
      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!!
      • Disaster Area? Hell no! They get Al Gore's Tony-nominated karaoke rendition of "Born to Run."
      • the newlywed alien couple will have Disaster Area play at their wedding

        It would probably be best if Disaster Area played on a neighboring planet to the wedding. Sure the grandmother of the bride can take out her hearing aids and not care but everyone else is probably going to find it hard to dance to.
  • by js7a (579872) * <james&bovik,org> on Saturday July 26, 2003 @11:26PM (#6542953) Homepage Journal
    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 [berkeley.edu]

    That seems horribly inefficient!

    Have the SETI people ever heard of cepstral [shef.ac.uk] techniques [libinst.com]?

    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!

    • by Anonymous Coward
      They refuse to make any optimization to the original program. Note the lack of even SSE support after all these years.
    • That seems horribly inefficient!

      I was under the impression that this had more to do with redundancy of complex data for purposes of security to ensure someone does not spoof data? If the analysis were to proceed by simply taking a derivative of the FFT and using that, the data would concievably be easier to forge? Perhaps this also is one of the reasons that the Seti@home crew is unwilling to make platform specific optimizations?

      • by js7a (579872) * <james&bovik,org> on Sunday July 27, 2003 @12:26AM (#6543158) Homepage Journal
        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.

    • by Skuld-Chan (302449) on Sunday July 27, 2003 @01:30AM (#6543309)
      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.
  • by Frank of Earth (126705) <frank AT fperkins DOT com> on Saturday July 26, 2003 @11:26PM (#6542957) Homepage Journal
    .. about 14000 hours for the past.. 6-7 years.

    And to think my computer use to just fly toasters when it was idle.
  • by civilengineer (669209) on Saturday July 26, 2003 @11:26PM (#6542958) Homepage Journal
    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?
    • by Black Parrot (19622) on Sunday July 27, 2003 @12:10AM (#6543110)


      > 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?

      • Aliens (Score:5, Funny)

        by TrollBridge (550878) on Sunday July 27, 2003 @07:00AM (#6543859) Homepage Journal
        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.

    • What about all the historical cases of UFO sightings?

      What about all the cases of people seeing images of Jesus in condensation on windows, or stuff like that? People will see what they want to believe.
  • by sllim (95682) <achance&earthlink,net> on Saturday July 26, 2003 @11:30PM (#6542972)
    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.
    • But there really isn't anything wrong with trying.

      Except that it'd be pointless, even if they did get a signal. It'd be a signal hundreds or thousands of years old.

      Besides, Seti@home really helped to bring about this idea of 'distributed computing' to the world.

      Pardon the pun, but what planet are you from? SETI was NOT the first, Distributed.net's RC5 challenge significantly predates the SETI@home client and was enormously popular. At least Distributed.net's ruler thing will be USEFUL.

      Oh, and i

      • by JudgeFurious (455868) on Saturday July 26, 2003 @11:59PM (#6543078)
        Well, whether or not the signal was hundreds of thousands of years old or from 15 minutes ago I can hardly imagine it being described as pointless. Evidence of life somewhere other than here, get that through your head. It would be nice to know that something else is going on out there or at the very least has gone on out there.

        SETI might not be the first but it's without a doubt the most widely known. That's got to count for something doesn't it? It's advanced awareness of distributed computing far more than any other application so far (unless there's a distributed porn program running around I'm not aware of).

        The list of shit people have pulled "back when they first started up" is miles long. I wouldn't have done it (re-fed the clients the same data over and over again) but it pales in comparison to some of the things that people have pulled in order to keep interest alive in their projects while they get things running smoothly.
      • by deglr6328 (150198) on Sunday July 27, 2003 @12:14AM (#6543118)
        "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.
      • While Rc5 was very popular, it was only really amongst us geeks. Seti@home has attracted a LOT of attention over the years, and now A LOT of non-technical PC users know what it is and what distributed computing is.
      • "Except that it'd be pointless, even if they did get a signal. It'd be a signal hundreds or thousands of years old."

        That's right--a signal from an ALIEN INTELLIGENCE is only useful if it is up to date.

        Also, SETI isn't under any sort of compulsion to prove to the people who use its client whether the data is "fresh" or not. That's silly.
    • in another 100 years our production of radio waves will have increased by several orders. Your logic is flawed I think.

      how many countries produce a radio signal? All of them. How many countries produce as many radio signals as the US? not many. how many will in ten years? Many more.

      How do you think your cell phone works? Hyper beams? Wi-Fi? That must be some sort of new physics the kids are using.
      • True about the production of them (if you can really say that radio waves are produced.. but that is another thread entirely).
        But we are talking about radio waves that are powerful enough to be seen light years away.
        That I think we are going to be getting away from.

        I expect that in 10 years there probably will be more devices using them, but they will be using them in a smarter way, say spread spectrum and such.
        I think we are moving towards 'doing more with less' as an attitude.

        But I still ask you, in 100
    • 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.

      Yes, and in 500 years, maybe we have the resources to put up a huge radio beacon right outside Pluto's orbit to see if anybody would pick up our signal. We would do that, just as we do SETI today, if it's cheap enough. Similarly, a sufficiently prosperous alien civilization might be putting up all sorts o

    • I have an entirely different reason that we probably won't find anything. Imagine a fully fueled space shuttle moving at .3c. If it were to hit a planet, it would release some 15 million megatons of energy. That's roughly 10,000 times the world's nuclear arsenal (at least according to the numbers that I've seen) released in the same spot all in the space of a sneeze.

      I've seen a design for a ship called the Valkyrie with a cruising speed of .92c. It accelerates for 6 months to get there and when it is a
      • hmm (Score:3, Insightful)

        by Bombula (670389)
        Now I'm no physicist, and I don't know how potential energy is measured relative to a pair of celestial objects, but assuming the velocity of the spaceship relative to the target planet started at something FAR less than .3c, wouldn't that mean that the spaceship somehow had to acquire most of that 15 million megatons of energy itself? Where would that come from? From it's fuel, or fuel it gathered along the way (magentic fusion ramjet equivalent or something)?
  • by 1984 (56406) on Saturday July 26, 2003 @11:30PM (#6542973)
    But, from the article:

    "Following up on what is an equivalent of a million years of computation..."

    When the RIAA talks about the "equivalent number of CD burners", it's a meaningless inflation. Here's another example. It would have served better to mention the number of SETI@Home clients. A true and meaningful figure which would still have conveyed the scale and a sense of awe.

    God, how pedantic and picky of me.

  • Cool! Now I'll finally be able to find my way home...
  • A little OT but (Score:5, Interesting)

    by geeveees (690232) on Saturday July 26, 2003 @11:38PM (#6542999) Homepage Journal
    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...
    • Re:A little OT but (Score:5, Interesting)

      by Gorobei (127755) on Sunday July 27, 2003 @12:23AM (#6543149)
      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.
    • 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...

      This is actually an interesting thought. Maybe we go hunting in the jungles of an alien world using our personal cloaking devices. Maybe we mass an armada to go from planet to planet sucking up their resources (hell, we did it on this planet why not when we go interstellar?). Maybe I take my giant robot to their cap
    • by Dag Maggot (139855) on Sunday July 27, 2003 @01:05AM (#6543256) Homepage
      Well, I for one welcome our new human overlords..
      oh wait...

    • Re:A little OT but (Score:2, Interesting)

      by cgenman (325138)
      I doubt we would abduct the inhabitants. History would show that's unlikely. How many Native Americans do you see wandering around the UK, or Aztecs in Barcelona? And now that we have become more advanced than our savage, killing predescessors, likely we will just put them up in tin shacks, make them ashamed of their nakedness, and force them to "work" for "money" to buy food while not actually providing jobs.

      Yes, our enlightened species would bring great things to these indiginous aliens. Wonders such
  • by JessLeah (625838) on Saturday July 26, 2003 @11:39PM (#6543006)
    OK... the article notes:

    "The next step is particularly fascinating, if a signal appears to have increased since the first observation put that star on the checklist."

    How could it have increased?

    These signals are coming from light-years away.

    Even if the aliens learned, somehow (say, a year ago) that we were listening for them, finding this out instantly via some sort of "subspace radio" or the like, the signals we have received since then were ALREADY IN TRANSIT when the SETI@home program began.

    Besides, there'd be no way for them to know we're listening, let alone to find that out within the last year.

    Or maybe I just grossly misread the poster's meaning?
    • Imagine the signal strength of Earth TV signals from 1945 through to when cable/dish TV started to cut into it.

      Also, they could have noticed us a while ago from radio signals, and we're only now getting the signal after they swung the antenna around to point at us.

    • How could it have increased?

      Perhaps the signal is from an object like a pulsar that is increasing in mass near its center and increasing its rate of spin a'la conservation of angular momentum? After all the first time a pulsar was discovered, it was thought to be "little green men".

    • How could it have increased?

      Perhaps it's the Vogon spaceship on its way to Earth, broadcasting the "you are about to be paved for an interstellar highway" message. It increased because the ship's getting closer...

    • by RestiffBard (110729) on Sunday July 27, 2003 @12:57AM (#6543242) Homepage
      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.
  • The WOW signal (Score:4, Interesting)

    by 198348726583297634 (14535) on Sunday July 27, 2003 @12:24AM (#6543153) Journal
    I'm surprised nobody has mentioned the WOW signal [bigear.org]. read the link..it'll send chills down yer spine!
  • So all the civilizations, capable of building radio beakons and moving them away from the star for clearer transmittion will be excluded, as every megawatt transmittion with goal of reaching other civilizations should originate by the planet!

    Hm. Strange ideas.

    "The next message will be sent by us in 0.00063 of galactic second".
  • As we are quickly discovering, RF isn't the ideal way to shuffle information around. As a result, Earth will soon (within decades) abandon RF in favor of pure optical communications. Assuming most intelligence follows a similar path, we can expect they will emit detectable RF for perhaps a century. On a geologic timescale, this is much less than the blink of an eye. Therefore the odds of us catching another intelligence when it is at the RF stage of tech evolution is vanishingly small. So fugeddaboudit
  • Greater Importance (Score:3, Insightful)

    by cliffy2000 (185461) on Sunday July 27, 2003 @02:53AM (#6543472) Journal
    It brought distributed computing to the forefront of media attention and to many user's desktops. For that, I give it credit.
  • Up in the air (Score:5, Interesting)

    by nimblebrain (683478) on Sunday July 27, 2003 @02:59AM (#6543483) Homepage Journal

    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 [planetary.org]

    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 [berkeley.edu] 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?

  • by p3d0 (42270) on Sunday July 27, 2003 @06:37AM (#6543830)
    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 [astrobio.net] today presents the skymap [astrobio.net] of where in the night sky to find the most promising [t-online.de] SETI@Home signals, along with the research plan for the March Stellar Countdown project [planetary.org] that produced it. The dedicated use of the Arecibo Telescope [slashdot.org] 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."
  • by The Lynxpro (657990) <`lynxpro' `at' `gmail.com'> on Sunday July 27, 2003 @08:36AM (#6543977)
    I was just thinking about this based upon a comment posted arguing that if life evolved on another planet similar to Earth and they developed fire, the wheel, etc. millions of years before us then they'd most likely have the radio as well. But if that's the case, then they would have had a Bill Gates figure exploiting their own ancient tech boom. So they too would have progressed to digital radio transmission, and their own music distribution industry would have insisted on protecting the content and then their Mr. Gates would've pioneered the march to encrypting their radio transmissions. So in all likelihood, what are the chances that a lot of those radio signals we are picking up that do not make any sense are encrypted signals being distorted to protect content? Or, what if their computer systems evolved off their own native versions of the Atari ST and Commodore Amigas versus Windows? (we'd be screwed!) And, if there are multiple spacefaring species out there, they too probably have defense strategies and they would definitely encrypt their broadcast transmissions. Just some points to ponder duing the wee hours here in Pacific Standard Time today...

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