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SETI Finds Interesting Signal

Several readers sent in notes about an interesting signal discovered by SETI. No real evidence of Someone Out There, but not fully explainable either. Another reader submits a blurb suggesting that aliens should send spacemail, not signals: "Rutgers electrical engineering professor, Christopher Rose, has an article on Nature magazine's cover today describing the most efficient way for our civilization to be discovered by aliens. On this question of better to 'write or radiate', his conclusions: better not to send radio transmission, when physical media like DNA on an asteroid can declare a terrestrial presence. Similar to what motivated Voyager scientists to attach a plaque for the outbound trip. Rose has some great information payload sizes as examples (like the entire information equivalent for our global genome fitting on a 100 pound laptop!)."

24 of 816 comments (clear)

  1. Re:DNA Over Signal by mOoZik · · Score: 3, Insightful

    Because the laws of physics - most specifically the inverse square law - work against the transmission of electromagnetic energies over vast distances. Isn't efficiency the pinnacle of any advanced civilization?

  2. A minor issue is that by rasafras · · Score: 4, Insightful

    Physical objects are a tad harder to find. We would be happy to find a civilization like our own... however, we didn't notice a rather large until three days after it had almost hit our planet. The other real snag happens to be major as well - it doesn't travel at the speed of light. Puts things on a slightly larger timescale, doesn't it?

  3. Re:DNA Over Signal by FlipmodePlaya · · Score: 4, Insightful

    Indeed. There's an outside chance that in 40,000 years Voyager will enter another solar system with its record (the plaque was on the Pioneers). The chances that a civilization exists there, and that they will notice and intercept it are unbelievably small. Why bother?

  4. Re:and we wonder where DNA technology is going. by Repton · · Score: 4, Insightful
    The universe is WAY too fricken big for us to be alone.

    But it could also be WAY too fricken big for us to be detectable...

    (try crunching some numbers WRT the invention of radio transmitters, the speed of light, and the distance to nearby stars)

    --
    Repton.
    They say that only an experienced wizard can do the tengu shuffle.
  5. Umm... by r00k123 · · Score: 4, Insightful
    ...the entire informational equivalent for our global genome?

    I think I might rather hang onto this information until we're sure our new-found neighbors are friendly.

  6. Re:Sending DNA doesn't seem like a good idea... by NotQuiteReal · · Score: 4, Insightful
    Sorry to reply to myself, but I forgot to make a key point; Why do we want to be discovered?

    I mean, it would be cool to discover intelligent aliens and all, but why have them discover us?

    I like to surf the internet, but for crying out loud, I have a firewall. I see the Internet, the Internet doesn't see me.

    I'd say just be cosmic lurkers until we are damn sure it is safe to be sticking our nose into things.

    Of course the odds of anything on this topic happening (good or bad) are so poor that I don't think anyone has to worry.

    --
    This issue is a bit more complicated than you think.
  7. Re:DNA Over Signal by gregmac · · Score: 4, Insightful

    How about sending out an object that transmits a signal? You still have a limited range around the object, but at least it will broadcast farther than earth broadcasts. Sending out a signal also increases the chances that an object will be located .. if we were to start picking up some mysterious signal that was nearby, we'd sure try to locate it. It could run on solar power, and only wake up and start broadcasting when it's actually close enough to a sun (in a solar system) that it gets enough power. I'm not sure what it would broadcast - zipping it around our own planet and having SETI alarms going off would probably be a good test.

    The other problem with earth-based transmission is that we don't do it anymore. We'd need large antennas broadcasting "we're here" signals outwards, and considering SETI already has problems with credibility while looking for signals, I'd imagine getting funding to send out signals would be even harder.

    --
    Speak before you think
  8. Re:send engineered DNA by Kiryat+Malachi · · Score: 4, Insightful

    What if we deliver this encoded DNA to a species that uses, say, a silicon matrix encoding their genetics?

    Why would they even look at DNA, if they didn't realize it was a way to encode info as well as the foundation of life for us?

    --

    ---
    Mod me down, you fucking twits. Go ahead. I dare you.
    (I read with sigs off.)
  9. Several billions times the matter of earth by ArcticCelt · · Score: 3, Insightful
    "...better not to send radio transmission, when physical media like DNA on an asteroid can declare a terrestrial presence... ...like the entire information equivalent for our global genome fitting on a 100 pound laptop"

    They just forgot one little detail:

    If we want to cover as much space as with a radio signal we have to sent several billions times the amount of matter available on earth to multiple directions at the same time. Its similar as with radio signals. The farther you send, bigger is the amount of space to cover and bigger is the number of probes you have to send to cover it.

    Just a little detail. :)

    --

    Yahh, hiii haaaaa! -Major Kong, from Dr. Strangelove
  10. Power supply by spineboy · · Score: 3, Insightful
    I imagine that the opwer requirements for a probe to broadcast anything that could outshine earths would be formidable and probably not feasable. The Voyager(or Pioneer?) probe that recently escaped our solar system (past pluto) after 15-20 years was undetectable.

    We'd need something with a renewable energy source, like a bussard ramjet, to be able to broadcast a decent signal strength.

    --
    ..........FULL STOP.
  11. AIEEEE! DON'T TELL THEM WHERE WE ARE! by qengho · · Score: 3, Insightful

    Hasn't anyone at SETI read The Forge of God? We need to just STFU and listen, not broadcast where we are so the Destroyers can find us! (In a nutshell: a highly paranoid alien race listens for broadcasts from nascent technological civilizations and eradicates them before they can become a threat.)

    Seriously, we have no idea of the mindset and capabilities of alien civilizations. The novel's viewpoint is arguable, but caution dictates that we determine the intentions of outsiders before we announce our presence (cf. American Indians vs. Europeans).

  12. Some things are universal, not cultural by AHumbleOpinion · · Score: 4, Insightful

    ... Therefore they are mathematicians and scientists. They use radio waves and other technologies that we use ...

    You do realize that in the SETI context "advanced civilization" means "technologically advanced civilization"? If they are an advanced civilization they will have a basic understanding of science, of how the universe works. Electromagnetism is an elementary part of that understanding. Our methods for establishing communication do not have a western or human bias. Counting off prime numbers is pretty neutral, an advanced civilization should recognize that this would be a quite improbable natural phenomena. Similarly the frequencies we would use for such signals would be pretty neutral, a multiple of a universal constant, another improbable natural phenomena. Some things are universal, not products of human or western culture.

  13. Re:DNA Over Signal by shawnce · · Score: 4, Insightful

    Actually the inverse square law holds for any thing with a initial fixed density that propagates from a point source.

    So say you throw 100 rocks (each with a placard saying "Eat at Joes") out in an even distribution across the night sky then the density of those rocks in a shell centered on and growing out from the earth will reduce in accordance with the inverse square law. The farther you get from the earth the bigger this shell gets and the farther the distance between the rocks in the shell.

    This increase in distance between the rocks means we have to get luckier and luckier that someone will actually see one or more of rocks and the little placard on it.

    So your statement is non sensical since the inverse square can affect a bunch of rocks or photons.

    Of course if we get lucky and someone happens to be inline with a rock they could get the message much better then a weak electromagnetic signal. Of course for every rock we send out we can send out trillions and trillions of photons in focused beams that can get their attention with enough signal strength to be useful. The beam can cover vastly larger areas then a rock ever could (now a rock with a say radio source could be interesting) and they travel just a wee bit faster ;-) then a rock.

    (I can see it now we launch a rock at a considerable fraction of light speed to get it out to a candidate world in a timely fashion only to get lucky and have a direct hit on their world... booom! Yeah they got the message alright.)

  14. Re:DNA Over Signal by Dashing+Leech · · Score: 5, Insightful
    So if you look at a given photon traveling through space its "signal" will not weaken with the square of the distance

    This is probably the key point. Yes, the energy density decreases with square of distance, but that just means you have to stare longer to see the signal. This is how telescopes can measure faint stars. If they look longer, more photons arrive. So if we sent a modulated signal (e.g., amplitude, frequency, phase) it would still reach other planets in a readible form. The modulation would just have to be very slow so they don't integrate the whole modulation over the "staring" period.

  15. Re:DNA Over Signal by Jim+Starx · · Score: 3, Insightful

    Yes, but where to point it? Lasers are only good if you know what you're aiming at.

    --
    The darkness... controls the music. The music... controls the soul.
  16. Re:we are looking for math. by JDevers · · Score: 3, Insightful

    Well, I would say that to produce a transmitter powerful enough to reach other star systems (and hence be of immediate interest to us) the civilization would have to understand at least the basic math of constructing that antenna. Of course you could say that an organic tech could evolve that, but in all honesty a civ advanced enough to genetically alter it's planet-mates to make transmitters would almost certainly have to understand the basic math THAT entailed.

    Color is an arbitrary thing, integer math is not arbitrary nor perceptual. Name me a method of perception that would change the number of continents on Earth or planets in our solar system. Even if they used reflected gamma radiation as a primary sense, there would still be the same number of rocks...

    A higher culture will understand math, maybe not the same formulas we do etc, but to say they don't have math is like saying they don't have chemistry. They may not have discovered it, but it still works there. As far as that is concerned, if they don't understand fundamental mathematical concepts, they aren't intelligent on a galactic scale and we will never find them anyway. Cuttlefish may generate EM, but they don't on a galactic scale. There is no immediate evolutionary advantage of being able to do that...

  17. Re:My God, it's full of primes! Seriously! by bhny · · Score: 3, Insightful

    new scientist is down.
    can you post that text file?

  18. It doesn't matter. by inertia187 · · Score: 4, Insightful

    As Carl Sagan's pointed out in is book, Contact, no matter how complex or compelling the message from beyond, there will be people who will think it's a hoax.

    Or to put it another way, even if God himself this very day with his own hand placed a crucifix in orbit around the earth replacing the moon, science would explain it.

    --
    A programmer is a machine for converting coffee into code.
  19. Re:Waste of time by merdark · · Score: 3, Insightful

    Sooo, do you think you have enough information to make a logical decision to use your emotions? If you don't have enough infomration to make semi-logical choices for the majority of common situtaion, then perhaps you haven't thought about those situations enough.

    Emotions were usefull in primitive society. Now, they often get you in trouble more than anything. Take anger. People following this emotion has led to road rage, killings, beatings, many firings, bad customer service, etc etc etc. Take love, people do SO many stupid things because of love. You think people would learn from these stupid things, but no. They do not. Or take greed.

    If there is a lack of information avaliable, the logical thing to do is to try to FIND information. Not fall back on primitive emotions.

    Perhaps what you are referring to are situations involving ethics. Where logic is perhaps too *harsh* to be applied. In these situations it is indeed wiser to follow one's emotions. But not because of a lack of information. Rather, because we are still quite primitive as a species. Regardless of what we think of ourselves, many of our actions are not at all logical, nor are the smart, or wise, or anything of the like. As a result, being logical in ALL situations will quickly get you branded a lunatic, heritic, insenstive, immoral, or any number of other derogatory terms.

    Humans still incredibly stupid. We all simply have a HUGE ego problem.

  20. Re:My God, it's full of primes! Seriously! by tobias.sargeant · · Score: 5, Insightful

    ncevysbby is aprilfool rot13'ed

  21. It definitely comes from earth by dustpuppy_de · · Score: 5, Insightful
    And, most probably, ist is nothing more than an artifact from the telescope.
    Nobody seems to have noticed this paragraph of the Article:
    What is more, if telescopes are observing a signal that is drifting in frequency, then each time they look for it they should most likely encounter it at a slightly different frequency. But in the case of SHGb02+14a, every observation has first been made at 1420 megahertz, before it starts drifting. "It just boggles my mind," Korpela says
    So, everytime they detected it it started at 1420 MHz and then started shifting? How could asignal from 1000 Lightyears away react in such a way? Do you think the aliens restart the signal every time we are looking?

    No, sorry, everyone. This looks pretty much. like a malfunction of the telescope in Arecibo.
  22. Re:Waste of time by JohnFluxx · · Score: 3, Insightful

    Applying logic to maximise your own gains would be very bad - that's why we have emotions, so that we try to maximise the gains for everyone. (Consider the prisoners' dilema)

  23. I see you've read by wiredog · · Score: 3, Insightful

    Uller Uprising by H Beam Piper.

  24. Re:Waste of time by Geoff-with-a-G · · Score: 4, Insightful

    If you want to be analytical, tell me where emotions come from.

    My thinking is that your brain is aggregating and analyzing data in quantities too large for your conscious thought (ration/logic/analysis/thought, whatever you want to call it) to keep up with. Take someone throwing a ball at you. To plot coordinates and calculate trajectory with your conscious mind would take far too long for you to catch it in real time. But you've got "lower" brain functions that can handle those calculations fast enough to be useful.

    I think of it like ASICs (Application Specifc Integrated Circuits - think graphics cards and network switches) vs. CPUs. Your "higher brain" can think up new stuff and analyze situations that your instincts don't recognize. But your "higher brain" is goddamn slow by comparison. So netiher one is "better" or "more correct", they're just suited for different situations.

    As for "If there is a lack of information avaliable, the logical thing to do is to try to FIND information", that doesn't work. For last resorts, go back to DesCartes - you can't prove anything 100%, because you can't even trust your own senses 100%.

    If you don't like my extreme example, I'll pick something more moderate. Watch Law and Order. When you look at a real life (yes, I know it's a fictional show, but it's a good model) you get the impression that it's almost impossible to prove something 100%, especially when you're being opposed. "Go get more proof" is not a valid approach, because there is a limit to the amount of information you can actually get. To get anything done, you eventually have to make a decision based on the information you have, and those decisions are often messy.

    In addition to those theoretical limits, there's a time factor. To steal a quote from the military mindset: "It's better to make a good decision now than the best decision later." Real life happens in real time, and delays cost you. Emotions analyze available input way faster than logic does, and most things operate on time constraints. So emotions will often serve you better than analysis, especially in situations where time is short and information is limited.

    To call emotions "primitive" is, I belive, a primitive characterization of important workings of the human mind.