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Looking For Aliens In All the Wrong Places

LtFiend writes "Evidently, some astronomers believe that SETI is searching the skies for the wrong type of signal. This new telescope built by Harvard will search for laser light and can detect pulses " as short as a billionth of a second." Looks like we'll need a new version of SETI at home so we can help with this one."

18 of 189 comments (clear)

  1. Extraterrestial Life and the Cosmic Time Scale by Masem · · Score: 4
    I rewatched 'Contact' this weekend, and it gets me to thinking on what chance we have as the human race (as in, over the next several millenia) will have in encountering a non-extinct, developed alien race. Humankind has only been around on the order of 10,000 years, and we'll probably have at least that coming in the future, but 20,000 years on the cosmic scale is a blink of the eye. Assuming that other races have similar 'lifespans', it may be easy enough to miss them because we started too late or too early. For example, we know that there's a narrow band where liquid water could exist on a planet based on our sun; what if earth's orbit was a few thousand kilometers closer: would life have developed a bit faster, and maybe humankind would have rose out 100,000 years earlier? Or mnay it would have been slower and we wouldn't be talking about this for yet another 100,000 years. And that's just earth we're talking about -- in any other solar system you'd have to worry about the same facts.

    I think the only thing we can safely say about extraterrestial life is that if we are going to find any with sufficient technological progress within the 'lifetime' of humankind, it will have to be from a very small cluster of stars near us, which might have been formed near the same time after the big bang, such that planets capable of supporting life would have all started the evolution timer at the same point. But again, that rate of evolution is so different that the chances of us seeing one another would be very very high.

    What I think we should focus on more (and it would be hard to say if we will be able to) is to look for the evidence of early life (single celled protozoa), or evidence of a race gone dorment, on other planets in the nearby cluster. Finding such would at least tell us that the development of life was not a chance happenstance on Earth.

    --
    "Pinky, you've left the lens cap of your mind on again." - P&TB
    "I can see my house from here!" - ST:
    1. Re:Extraterrestial Life and the Cosmic Time Scale by DickBreath · · Score: 3

      Interesting thought.

      But you raise a huge question. You suggest that we should start looking for something else. But you don't suggest how.

      Specifically, using current technology, how would you look for signs of early life or past life? What phenomena would we be trying to detect using what kind of instruments?

      Again, I don't think your idea is bad, I just don't see how it can translate into practical action.

      Any ideas?


      You can kill the revolutionaries, but you can't kill the revolution. Thus leaving a revolution that is carried out by non-revolutionaries. So why have a revolution?

      --

      I'll see your senator, and I'll raise you two judges.
  2. I have to disagree with the article by JetJaguar · · Score: 3

    While such a thing may be technically possible, these guys seem to be glossing over some very big problems.

    1. Optical communication across interstellar distances is going to suffer from severe extinction (signal absorption by intervening dust). Even if you can generate a laser pulse brighter than the sun, interstellar extinction is a big problem to overcome.

    2. A laser beam is very tightly confined, and would have to be aimed very precisely in order to "hit" it's target. The probabability that the Earth would just happen to cross one of these "lines of communication" is incredibly small.

    So it seems to me that while optical commmunications could work in principal, radio is going to be much easier to work with, since you don't have to worry about extinction or pointing problems as much.

    --

    Shop Smart, Shop S-mart!

    1. Re:I have to disagree with the article by DickBreath · · Score: 3

      Don't laser beams spread apart, just very slowly? Don't lasers have ratings of divergence that are measured in extremely small angles? I'm no expert on this. I just recall seeing HeNe lasers in Edmund Scientific that had a "divergence" or somesuch measured in some thousanths of a radian or something. Many years ago.

      --

      I'll see your senator, and I'll raise you two judges.
  3. Who to contact? by Black+Parrot · · Score: 3

    My assumption is that the intelligent species out there aren't advertising their presence. Anyone worth contacting is probably dangerous.

    --

    --
    Sheesh, evil *and* a jerk. -- Jade
  4. My Grade 12 Thesis Paper Was On This Very Topic by citizenc · · Score: 3

    For my grade 12 english thesis paper, I wrote said paper on this very subject. Feel free to read it: Get Probed.

    ------------
    CitizenC

  5. The real site for Optical Seti is by chriscappuccio · · Score: 4
    www.oseti.org

    This is the Harvard group's page.

  6. Now... by Raymond+Luxury+Yacht · · Score: 3

    ...doesn't this make sense? I mean, if they're far in advance of us, or even about par, who is to say that they did use or still use radio waves?

    We came up with radio for the transmission of sound (at least, if I am wrong about that, don't kill me :) ), and how do we know that every life form would use SOUND as communication?

    Also, I hate to say it, but I mean, look at our planet and our people. If YOU were out looking to meet someone, and the first person you ran into was a raving loonie, attacking various parts of his/her own body/pod/gelatinous mass and still mired in the belief in some mystical deities... wouldn't you KEEP looking? Personally, I'd be willing to bet that aliens are out there looking at us like we are the little "challenged" kid down the block, and they are coming up with secret code to keep us from finding them out. And sooner or later they'll be like "Oh shit... they saw us... pretend you didn't notice and run back into your backyard, man... I don't want to hang out with MANKIND. They'll break all our toys."

    --

    Ceci n'est pas une sig.
  7. great... by .c · · Score: 5

    'Zeelub, stop pointing your laser-pointer at Earth -- you're making the mammals excited.'

  8. Not Wrong by bluelip · · Score: 4

    Room for all scans. We have an over-abundance of computing power to process these signals as is evident with sei@home. Why is searching using radio signals wrong? Once the sensors are built, there are millions of people willing to spend their cycles analyzing your data. I believe there is room for both projects, and many more.

    Also, won't most stellar bodies block laser light , whereas Radio signals will tend to 'bend' around them?

    --

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    More incorrect spellings can be found he
  9. Ouch! by istartedi · · Score: 5

    Harvard University, said: "Using only Earth 2001 technology, we could now generate a beamed laser pulse that appears 5,000 times brighter than our sun, as seen by a distant civilisation in the direction of its slender beam.

    What will it say? Make Money Fast? Send back a green flash if you want to be removed from our beam-list?

    --
    For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
  10. OT? You decide. by IronChef · · Score: 5

    [by Terry Bisson; originally appearing in OMNI Magazine]

    Imagine if you will... the leader of the fifth invader force speaking to
    the commander in chief...

    "They're made out of meat."
    "Meat?"
    "Meat. They're made out of meat."
    "Meat?"
    "There's no doubt about it. We picked several from different parts of
    the planet, took them aboard our recon vessels, probed them all the way
    through. They're completely meat."
    "That's impossible. What about the radio signals? The messages to the
    stars."
    "They use the radio waves to talk, but the signals don't come from them.
    The signals come from machines."
    "So who made the machines? That's who we want to contact."
    "They made the machines. That's what I'm trying to tell you. Meat made
    the machines."
    "That's ridiculous. How can meat make a machine? You're asking me to
    believe in sentient meat."
    "I'm not asking you, I'm telling you. These creatures are the only
    sentient race in the sector and they're made out of meat."
    "Maybe they're like the Orfolei. You know, a carbon-based intelligence
    that goes through a meat stage."
    "Nope. They're born meat and they die meat. We studied them for several
    of their life spans, which didn't take too long. Do you have any idea
    the life span of meat?"
    "Spare me. Okay, maybe they're only part meat. You know, like the
    Weddilei. A meat head with an electron plasma brain inside."
    "Nope. We thought of that, since they do have meat heads like the
    Weddilei. But I told you, we probed them. They're meat all the way
    through."
    "No brain?"
    "Oh, there is a brain all right. It's just that the brain is made out of
    meat!"
    "So... what does the thinking?"
    "You're not understanding, are you? The brain does the thinking. The
    meat."
    "Thinking meat! You're asking me to believe in thinking meat!"
    "Yes, thinking meat! Conscious meat! Loving meat. Dreaming meat. The
    meat is the whole deal! Are you getting the picture?"
    "Omigod. You're serious then. They're made out of meat."
    "Finally, Yes. They are indeed made out meat. And they've been trying to
    get in touch with us for almost a hundred of their years."
    "So what does the meat have in mind?"
    "First it wants to talk to us. Then I imagine it wants to explore the
    universe, contact other sentients, swap ideas and information. The
    usual."
    "We're supposed to talk to meat?"
    "That's the idea. That's the message they're sending out by radio.
    'Hello. Anyone out there? Anyone home?' That sort of thing."
    "They actually do talk, then. They use words, ideas, concepts?"
    "Oh, yes. Except they do it with meat."
    "I thought you just told me they used radio."
    "They do, but what do you think is on the radio? Meat sounds. You know
    how when you slap or flap meat it makes a noise? They talk by flapping
    their meat at each other. They can even sing by squirting air through
    their meat."
    "Omigod. Singing meat. This is altogether too much. So what do you
    advise?"
    "Officially or unofficially?"
    "Both."
    "Officially, we are required to contact, welcome, and log in any and all
    sentient races or multibeings in the quadrant, without prejudice, fear,
    or favor. Unofficially, I advise that we erase the records and forget
    the whole thing."
    "I was hoping you would say that."
    "It seems harsh, but there is a limit. Do we really want to make contact
    with meat?"
    "I agree one hundred percent. What's there to say?" `Hello, meat. How's
    it going?' But will this work? How many planets are we dealing with
    here?"
    "Just one. They can travel to other planets in special meat containers,
    but they can't live on them. And being meat, they only travel through C
    space. Which limits them to the speed of light and makes the possibility
    of their ever making contact pretty slim. Infinitesimal, in fact."
    "So we just pretend there's no one home in the universe."
    "That's it."
    "Cruel. But you said it yourself, who wants to meet meat? And the ones
    who have been aboard our vessels, the ones you have probed? You're sure
    they won't remember?"
    "They'll be considered crackpots if they do. We went into their heads
    and smoothed out their meat so that we're just a dream to them."
    "A dream to meat! How strangely appropriate, that we should be meat's
    dream."
    "And we can mark this sector unoccupied."
    "Good. Agreed, officially and unofficially. Case closed. Any others?
    Anyone interesting on that side of the galaxy?"
    "Yes, a rather shy but sweet hydrogen core cluster intelligence in a
    class nine star in G445 zone. Was in contact two galactic rotations ago,
    wants to be friendly again."
    "They always come around."
    "And why not? Imagine how unbearably, how unutterably cold the universe
    would be if one were all alone."

  11. Just hope we're the target by ocelotbob · · Score: 3
    Now, correct me if I'm wrong, but isn't the point of laser communication the fact that the signal does not dissipate nearly as much as a regular beam of light? So it goes to argue that we'd never see the signal unless someone was pinging us to see if there was anybody on Ulmach or whatever they call our little stellar system.

    However, it also once again emphasises the we need to take a somewhat more proactive approach and not just receive from systems that are possible targets for life, but also send out. After all someone has to be the initiator of conversation, and who's to say there is life out there, but they too are just listening and not sending.

    --

    Marxism is the opiate of dumbasses

  12. Then after that... by Fervent · · Score: 5
    Present: Radio signals? What alien would use radio signals? They'd have better technology than that, right? Use light.
    10 years later: What alien would use light? Use quantum particles.
    10 years after that: What alien would use quantum particles? Use antimatter.
    10 years after that: What alien would use antimatter? Use quark synthesis.

    Eventually we're just going to find we should have been searching for bacteria on fallen meteorites.

    -
    -Be a man. Insult me without using an AC.

    --

    - I don't care if they globalize against free speech. All my best free thoughts are done in my head.

  13. BAH! by jonfromspace · · Score: 4

    I think it is obvious that Hemos is an alien and is trying to throw us off the trail...

    Sashdotters, I say install SETI@Home on every system you get near, someone write a nasty little email virus that installs the software... lets track those aliens down and EXPOSE HEMOS!

    --
    I am become Troll, destroyer of threads
  14. laser is a poor method to scan for contact by corvi42 · · Score: 3

    This article is quite silly. Laser light communication would be excellent for communicating to a civilization - but only once you knew where they were. The problem with lasers is that they are highly directional. you need to point them in the direction you want to make a broadcast to and then send you're message. This would entail that any aliens sending out a general "hello and welcome to the club" message, or even just the ambient signals of their civilization, would need to have established the exact position of our planet from very far away.

    Think about how many stars are visible to the naked eye - hundreds of thousands. Then think about how many are visible through high powered telescopes - millions. now think of the task of analyzing each star to establish to a high degree of accuracy its particular movement so that you can know exactly where it will be in the thousands of years in the future when your signal will actually arrive at it. And even once you'd done that you'd have to broadcast in such a wide area around the stars position such that the signal could be received by any orbiting planets. That's a computational job on a scale many millions of times greater than simply sending out an all points radio broadcast. and radio waves still travel at the same speed as laser light.

    Plus with a laser the beam is so narrow that any dark matter ( think planets, large dust / gas clouds ) which might float by in the time between broadcast and receipt, and happen into its path could block the signal or alter its direction in uncalculable ways.

    Overall radio is much more efficient for sending out a general "welcome to the sentience club - wanna play the swap ideas game?" type message.

    --

    There are a thousand forms of subversion, but few can equal the convenience and immediacy of a cream pie -Noel Godin
  15. Bury the lead! by Cytotoxic · · Score: 3

    The strangest part of this entire article is the last paragraph.

    In October, 1989, a Russian news agency reported that scientists claimed to have established that a city in the former Soviet Union had been visited briefly by a spaceship crewed by three feet tall humanoids and a robot.

    The whole article is about using a telescope and computers to look for aliens on distant worlds, then at the end we learn that they have been hanging out in Russia all this time!

  16. Interesting article, but what was that at the end? by cavemanf16 · · Score: 3
    I think it is good for us to be using both radio and optical telescopes as we can learn things about the cosmos besides just alien life. A previous poster to this discussion noted that some quasars and other anomaly were found thru SETI@home, which supports this theory.

    What I didn't understand, was why in the world did that article contain the bit about Russian scientists claiming evidence of: three foot tall humanoids and a robot???!!! That had almost nothing to do with the article and was from 1989! I wonder what prompted the writer of the article to throw that in?