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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."
The media tends to like controversy because it sells better. None of the SETI researchers has claimed that "SETI is searching the skies for the wrong type of signal". Horowitz, who is building this all-sky optical search, has been doing microwave SETI for decades. He is the genius behind the META and BETA searches. Just because people are now exploring the optical regime does not make microwaves a less likely place to find an alien signal. All it means is that the researchers are trying something new. Why try something new? Because our technology has advanced to a point where they can. Also because the researchers get bored with old ways and want to try something different. It can get pretty monotonous doing the same kind of thing year after year with no positive results.
SPOON!
-- Too lazy to get a lower UID.
Now certainly I may be way low -- it HAS been 65 million years from the last major planetary event that caused a mass extinction, but even if you start pushing the timeframe of humans up to 100,000 or a million years, you are still talking about blinks of an eye relative to the estimated age of the universe. But again, the key thing is that one takes the assumption that races might die out -- if you assume otherwise, then yes, as the age of the universe increases, the chance for finding life should increase also.
"Pinky, you've left the lens cap of your mind on again." - P&TB
"I can see my house from here!" - ST:
I'm not saying SETI should be shut down -- because there is the possiblity we'll get something and all these arguements are moot. But it's more just looking at the big picture and realizing that we might just be shooting pot shots into space.
"Pinky, you've left the lens cap of your mind on again." - P&TB
"I can see my house from here!" - ST:
It wouldn't bend around them, radio waves would pass through them. Radio waves tend to be too low of an energy to be picked up by atoms to induce electrion jumps, so they'll pass through objects with no problem (that's why you can get radio and attenna TV inside a house) .. although with a planetary-sized body there will be some distortion. Light waves, on the other hand, are easily picked up by most metallic substances, and therefore will be absorbed.
"Pinky, you've left the lens cap of your mind on again." - P&TB
"I can see my house from here!" - ST:
And the next step up from galaxies is "galactic cluster", where again it's suggested there's some central object which several galaxies tend to gather about, but certainly not as strong that keeps planets in orbit or stars in orbit.
"Pinky, you've left the lens cap of your mind on again." - P&TB
"I can see my house from here!" - ST:
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:
Anyone remember a comic book from the late '80's called "Stray Toasters"? It was about a demon that took a vacation from Hell in New York, and started messing with some really deranged people, lawyers, etc. "Toasters" were demons. (well, it's what they do, right? stick ya with a pitchfork, and hold you over the flames. . . )
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
In human years:
5,000,000 BC
An alien race has evolved intelligence, develops technology and decides to attemtp to contact other intelligent beings using broadcast radio signals.
4,000,000 BC
Another alien race contacts the first race.
2,000,000 BC
These two races have build a huge trade confederation, and have discovered several other races. Humanity is not beyond their frontier, but has not been physically detected. At this point, humans are still spearing wooly mammoths. Several other pre-technological races have been discovered and were nurtured until maturity, when they could join the confederation.
1,000,000 BC
Huge interstallar war wipes out most civilization.
100 BC
On one planet where civilization survives, a new, conservative, isolationist government comes into power. They cease all contact with alien planets, they cease broadcasting.
1900 AD
Humanity has developed into an intelligent, industrialized society on the verge of technological advancement.
2000 AD
Humanity has been listening to the heavens and broadcasting signals, in hopes of contacting an alien race.
2100 AD
A violent civil war on Earth resulted from a combination of depletion of natural resources, destruction of the environment, and massive copy-protection schemes. Humanity is nuked back to the stone age. Both consumers AND business loses. Global warming melts the ice caps, and floods the continents killing all surviors.
2501 AD
A violent civil war on the alien planet unseats the traditionally conservative isolationist government. The new regime soon resumes broadcasting and listening for signals.
2,000,000 AD
Alien archeologists find evidence of a past civilization on a small planet, which was located just a few light years away from one of the main trade arteries of the old confederation. The surface is covered with ice, beneath the crust lie ruined cities, and craters, evidence of a massive nuclear conflict. Scientists are still unable to decode the contents of data disks recovered from one of the sites; almost as if the data were purposely scrambled. No big loss, since it was a copy of Titanic on DVD.
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
Alternatively, if you were to go down into the IR, you'd at least have a better chance of the signal getting through (less extinction in the IR), but you still have the problem with the beam size being pretty tight, as well as the need to be looking at the right place at the right milisecond.
Shop Smart, Shop S-mart!
I'm afraid you haven't convinced me. Extinction may not be a problem between the sender and the intended reciever, but for an interloper such as us? When we're not exactly sure what is we're looking for? When the pulse may be compressed into something unrecognizable? Not good. As for the IR, see my other post about that. Yes, looking in the IR is a much better choice.
As for 2, that is not a major error, but I did not explicitly state my entire reasoning, so let's think about it for a second. Yes, the beam will spread, and as it spreads, you lose power. Our ET's are going to want to use as little amount of power as possible, hence the beam will more likely than not, be as focused as possible. Unless they are sending an "is there anyone out there" message, which I would put odds of 50-50 on that right there.
Finally, even if the beam width is larger than the size of the solar system, is that really significant? I would argue that it is not. Catching gamma bursts will be easier, they are at least going to be more frequent...
Shop Smart, Shop S-mart!
You're going to pick up a lot of noise with that technique. Not to mention the loss of signal strength, assuming you can detect the signal at all.
Shop Smart, Shop S-mart!
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!
>My assumption is that the intelligent species out there aren't advertising their presence.
Interesting assumption. Too bad the only example we can test it against in the universe (ie, humans) violates it.
Violates it? Barely. How far are our radio emissions distinguishable from background noise? I thought it was only a few dozen light years. And IIRC, according to the recent Scientific American article on SETI a couple months back, although we could send directed communications for thousands of light years with an Arecibo, our current searches wouldn't detect an 20th century level civilization at any distance.
We make no attempt to hide our presence. It's pretty conceivable to me that other species could make the same "mistake".
Unless it really is a mistake. It could be that a sizable minority of species in the galaxy is both malevolent (in the sense that they would destroy weaker, expanding technological civilizations in order to avoid future threats to their own existance), yet hiding their presence (perhaps because they fear a more powerful, yet similarly hiding civilization). In such a scenario, any emerging technical civilization which did not adopt a hiding strategy would be toast before it was finished colonizing it's own solar system.
There's a cute Fermi's Paradox discussion on sci.space policy about all this, if anyone's curious. It's mostly died down, but you can check Deja.
It's weird seeing posts from someone who banged my exgirlfriend...
.5cm) laser fried from earth is a couple of tens of meters, IIRC, when it reaches the moon. It's still a lot less spread than cube-of-radius (or whatever, i'm tired) for an omnidirectional radio broadcast, especially when taking into account the strength of signal received.
Optical SETI, IMHO, has a much better chance of success, simply because laser "beacons" are much easier to construct, and make detectable, across space than are easily dissipated radio waves.
The laser will spread out, but the pulsed nature of the beam (eek, a pulsed beam) allows for greater power, and the beam still won't spread as much as a radio transmission. A laser's light is all moving in one direction, and starts not only focused, but collimated. Example of spread: a pencil-thick (say
gigantino.tv - Heavy but weighs nothing.
Kudos to Andrew Howard (my former roomate)! You know you've hit it big when your thesis work is getting written up on slashdot.
Then again, he's making the rest of us researchers look like a bunch of slack-jawed yokels.....
Loening
Error: That's NRAO, Green Bank West Virginia.
(picky, picky I know, but we of WV descent are sensitive to being lumped in with them rebels over in Richmond).
try { do() || do_not(); } catch (JediException err) { yoda(err); }
The signal would be designed to technological
level of receiving race they desired.
Could be a relatively simple signal if they want
to reach a lot of races or very sophiscated if
they wanted a high tech level.
Humans would notice patterns in light signals
thousands of years ago; radio only 75 years ago;
and some known physics not yet.
Me, I'd just laugh about it. Welcome to the wonderful world of science, where you can't just flip the card over and look at the answer. Time and effort spent looking is rarely really wasted, even if it eventually turns out there was nothing to find. Pulsed laser beams is just another thing to try. Maybe we should be scanning through gravity waves, too. Who knows? Maybe any lifeform that has any real sense uses controlled quantized subspace variations to communicate over interstellar distances, and they figure no-one else is intelligent enough to talk to yet.
Yeah, using gravity to transmit would be cool, and it could actually be instantaneous (eg, getting rid of that speed of light barrier for communications). The thing is, we don't know whether or not it's instantaneous (gravity could well be limited by the speed of light, or the "speed of gravity". Also, we have no way of transmitting like that right now :P
Oh, and yes, it was N-Space.
My plan is to pimp before they realize I'm a jackass. Hit 'em hard and fast.
Man's understanding of radio waves is - how old? - a little over 100 years. Before Maxwell, people had no conception that such things might even be there?
If aliens are actually out there, chances are they either are way behind radio, or have found a communication method far superior to radio, something of which we have no concept whatsoever.
I saw Buckaroo Banzai on TV over the weekend.....The answer is obvious - the aliens live RIGHT HERE, but in the 8th dimension.
I heard it from John Bigbootie!
But Herr Heisenberg, how does the electron know when I'm looking?
Are we likely to detect alien races using optical technology? For one thing most lasers are fired down itty bitty pieces of cable, not out to space, and for another, I can hardly imagine being able to detect an alien laser pen at a distance of over 4 light years.
One argument for the unsuccessful detection of radio using aliens has been that this technoly has such a short lifespan in comparison to that of a civilisation e.g. we started using radio about 100 years ago, and we're likely to stop within 30 or so years due to optical technology supplanting it.
The question is what is the likely lifespan of laser technology in the lifespan of a civilisation? How long will it be till we discover something other than coherent light to transmit messages etc ?
Donte Alistair Anderson Roberts - hi son!
Karma: Chameleon
Simply because laser radiation is detected, doesn't necessarily mean that an intelligent entity sent it. This article from the Goddard Space Flight Center describes natural laser radiation from the atmosphere of Mars (basically a sun-pumped CO2 laser). Similar findings have been observed in comets.
- Demosthenes
When I saw the title 'looking for aliens in wrong places' I almost expected the article to say 'after spending millions and millions of dollars to search the sky for aliens, first alien was actually found behind the sofa pillows.' And then I thought 'But how would it get there?'
-- ATTENTION: do not read this sig. It doesn't say much.
I always thought it was strange that they never looked at Orion, when it was so obvious... hang on... there's someone at the door...
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
The one thing that truely strikes me as odd about both the previous search for radio signals and now the search for laser bursts is while "guessing" at what an intelligent and advanced species might use to communicate we ignore the technology on our own world.
Right now we have people researching how to use quantum technology for both instantaneous communication as well as encryption. This technology is hard to evesdrop on in the first place, and if you do you can destroy the message due to the basic laws of quantum physics.
If we "primative" humans are researching this why wouldn't another race elsewhere in the universe be using something similar, or more likely more advanced?
No way. We want the giant green women!!!
-c
I have discovered a truly remarkable proof which this margin is too small to contain.
You can bet that of people who hear of this project, those who are the equivalent of CB burpers will be waving laser pointers at the Moon and random satellites. If we had megawatt lasers easily available, by now someone would have etched "Hi Mom" across the Moon.
RF searches are most likely to find someone who went through the same logic as us and have broadcast the same type of signal which we're looking for. Detecting leakage is less likely -- look at our broadcasting antenna farms, sending megawatts along horizontal planes to cover the Earth's surface; the Earth's surface is rotating, creating rotating beams which would flicker weakly across receivers every 12/24 Earth hours (plus 3 minutes).
We are most likely to hear dead ETIs. Anyone broadcasting will attract the script kiddies of the Milky Way -- assorted easy-to-create hardware with assorted purposes which is attracted to modulated signals. Any civilization with all its eggs still on its home planet won't survive any space-based intruders.
Spiced Milk Tea? I don't get it...
--
"It's tough to be bilingual when you get hit in the head."
--
Yes, this is absolutely right. They're just different frequencies, different sizes if you will, of the same basic thing. However, you still need different technologies to deal with them: You can't broadcast radio with your flash light, and you can't see anything by the light of a cell phone tower. For a variety of technical reasons, it might be easier for a large civilization to use lasers to communicate instead of radio. Not necessarily easier, just maybe. And so that means it's worth at least taking a look!
For example, lasers are small and can be re-targeted between stars very rapidly. Paul Horowitz has some designs for a setup with moving mirrors which lets you keep your laser stationary but aim its beam at dozens of stars every second. Radio, on the other hand, requires tremendous dish antennae to aim properly, so you can't slew between many stars anywhere near as fast. If you're an alien civilization trying to broadcast to as many targets as you can with limited resources, this might be a good reason to choose the optical over the radio.
Beyond that, there is no problem about having to calculate the motions of stars over time. We're trying to target close-by stars, which means the travel time is *not* the thousands of years you talk about, but rather only tens or hundreds, which means the stars move hardly at all. Even for more distant stars, note that the galaxy takes a quarter *billion* years to rotate once. Even ten thousand years doesn't move anything all that far. Besides, measuring and tracking the proper motion of stars isn't the computational hassle you seem to think it is. We know the proper motion for thousands of stars, and NASA is working on improving that tenfold with the upcoming SIM mission.
You also seem to think that broadcasts leaking out in all directions are the way to go. THat's not at all clear, because any broadcast spread over the whole sky will necessarily be weak in power. By focusing the beam through a telescope, whether radio or optical, you can get beam powers hundreds of thousands of times brighter than with an omnidirectional transmitter. So even for radio communications, I'll take the extra effort of aiming at different stars for a hundred thousand times stronger signal, thank you very much.
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.
Yes, extinction is going to be a consideration. But it's not all that hard to overcome. Look at it this way: If your laser pulse is 100x brigher than your sun on this side of the dust cloud, it's going to be 100x on the other side, too, even if both the sun's light and the star are both reduced by a factor of ten or whatever. They scale together. Anywhere you can see our sun from, and more, you could see our lasers. In fact, if you use a laser on the redder side of things, say even in IR, you're going to have much smaller extinction for your laser than for the star's light, and you'll win out even more in the long run.
Furthermore, radio signals suffer phase shifts and delays due to the intersteller medium. This tends to spread out a signal, originally sent at a narrow wavelength range, into a broader and fainter signal. You don't have this problem with IR or optical lasers, so that's a win for them.
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.
Wah, major error! Time to go brush up on your optics some more. A laser beam does spread out as it travels, in exactly the same way and at exactly the same rate as radio waves do. Diffraction-limited optics is the same for all frequencies:
S = lambda/D*R
That is, the beam size is proportional to the wavelength, divided by the size of your transmitting telescope, times the distance the beam has traveled. For larger lambda (i.e. radio) you need to use a larger telescope to get as focused a beam - but we do that already, that's why radio telescopes are so much larger than optical ones. Besides which, you neglect the fact that it's *trivially* easy to send as wide a beam we want, just by de-focusing the telescope a little or using a smaller telescope. It's sending narrow beams that's hard! Wide is easy.
The long and the short of it is this: By the time ANY signal, radio, optical, or whatever, has traveled the many lightyears to some other star, the beam will have spread out to be *much* larger than the target solar system. This is true because all forms of light spread out the same way as they travel, and because it's trivial to send as wide a beam as we want just by de-focusing things a bit.
I don't see how this effects seti@home. The "pulsing light detector" sounds pretty strait forward. If you see a flashing light, you found something now go analize it. With radio there is all kinds of noise so you need a lot of computer power to look for something which you want to study in greater detail, hence seti@home. With this telescope, as soon as you see anything, it is worth studying in greater detail. Think of the logs...
1:00:00 AM - no signal
1:00:01 AM - no signal
1:00:02 AM - no signal
...
I still think we're crazie script kiddies
if we think it's a good idea to connect our
global internet to a radio telescope,
hoping some alien message finds its way in.
If we're lucky, they'll put up a little popup
window to tell us we're owned...
(Mod the parent of this post up)
Exactly!
Why bother communicating with the aliens on other planets when we haven't talked to the ones that are already on our planet.
Presumably if they have the technology needed for interstellar travel, they also are well aware of the proper protocols for interstellar comunications. Presumably the method of communication they use exceeds the speed of light (or it at least exceeds c as we perceive it) So using any method based on light or other EM spectrum will likely be fruitless.
Work for Change & GET PAID!
My question is how are they different. If a culture can send coherent EM transissions in the visible light range, then why wouldn't then send them in a variety of frequencies including the radio frequencies that SETI is already listening for.
I mean there is no REAL difference between "radio" and "light" is there? They're both EM particle/waves aren't they? (If I'm wrong please correct me, I've never taken a physics class in my life).
Work for Change & GET PAID!
I've considered this possibility for a very long time though my idea was that the sun was possibly drowning out all signal that we could potentially capture. I mean really how difficult would it be for some naturally occuring process to interfere with radio broadcasts? I'm sure this has been thought of before but why has it never been brought up?
http://www.livejournal.com/users/cixel
For my grade 12 english thesis paper, I wrote said paper on this very subject. Feel free to read it: Get Probed.
------------
CitizenC
Yea - kinda inappropriate I think. There's a _much_ better article up at New Scientist.
SETI should also be using STM microscopy to look for sub-quantum alien worlds on the surface of electrons - its just as likely a location as deep space.
A W S ----------- QABO : BALA
sound doesn't exactly travel well in near vacuums
This is the Harvard group's page.
You are missing the main point, though. The idea is to discover if there is intelligence out there, we'll work on figuring out what they are saying later. SETI is trying to find ANY signal that looks to be artifically created. I'm sure that if we received Alien HDTV signal or the Galactic Quake login prompt, we'd know that it is a sign of intelligence, even if we didn't know how to decode it.
Never underestimate the bandwidth of a 747 filled with CD-ROMs.
we stand a better chance of eavesdropping in on cross-chatter, if such a thing exists.
As others have pointed out laser transmissions are good if you want to get ahold of Uncle Nrgnrr'c two star systems over and wish It happy birthday twenty terrestrial years from now ... Lasers would be highly efficient assuming there is nothing between you and Nrgnrr'c's receiving station. I suspect for point-to-point communications within our current understanding of physics a laser or laser-like device makes sense. If we are somewhere around the fringe of the transmission we should be able to at least detect it, even if we cannot decode it.
Then again as others have mentioned, if Nrgnrr'c uses some form of communication beyond our current understanding of the universe, say E.T.OL Instant Hypermessenger, then we're S.O.L. until we attain a workable knowledge of the different laws under which it's communications operate.
In my opinion SETI is worth the try -- if we succeed then one of the greatest questions imaginable will be answered. It does not matter whether or not they send us an Encyclopedia Galactica, or if they're in another galaxy, or if they ever even deign to speak with us.
We would know we were not alone.
If we find nothing then we still have an answer. Maybe if a few dozen years from now we've still found nothing then we'll pay a bit closer attention to the special place our noisy little planet holds in this overwhelmingly huge, deeply silent universe. Maybe we'll treat it a little bit better.
Maybe the voices of Earth life will fill the void between the stars several million years from now, and make the universe a less lonely place.
Get off my virtual lawn, you damned virtual kids!
Personally I think humans are far too arrogant in their perception of themselves as somehow superior to Earth's other DNA/RNA carriers. We are not the biggest biomass on the planet. We are not the most numerous species. Other species have had similar impact on the world's climate -- look at the murderous rise of aerobes and imagine the extinctions associated with the sudden permeation of oxygen through an anaerobic biosphere.
For a few years I have held the belief that the perpetuation of DNA/RNA is the driving force of life on Earth. Anything that passes on its DNA is successful in the grand scheme of things. I kind of see Earth as a big colonial organism, sort of like a slime mold. I see humanity as that slime mold's latest attempt to reproduce itself by flinging its spores ever further, even into space itself, and to other worlds.
I suspect that if we should somehow manage to wipe ourselves out (and do so without killing off some of the other more clever species -- some cephalopods, other primates, cetatians) something else will step in a few million years from now and continue the push of perpetuating Terrestrial DNA/RNA.
But I would just as soon have humanity succeed in this venture as to wait a hundred million years for air-breathing octopii to visit other stars.
Get off my virtual lawn, you damned virtual kids!
what does this have to do with seti? yeah, there are plenty of other successful DNA/RNA carriers. plants.... insects.... but they're not going into space...
Me commenting in the wrong area at 2 AM with not enough sleep. Apologies. :)
I think I was agreeing with your idea re: the accuracy of Drake's equation. We basically don't know what direction or form extra-Terrestrial life will take. SETI could be seen as a way of determining the accuracy of Drake's equation.
Possibly? :)
Get off my virtual lawn, you damned virtual kids!
Hey, maybe cosmic rays are some really tightly encoded pulses of information being sent across the universe by other species? Maybe everytime a species figures out how to send out a cosmic ray pulse, they send their response then die out before ever getting a response back, therefore explaining the long periods between cosmic rays! Many species are constantly trying to communicate with each other all the time, they're just dying out before anybody actually can. :)
Maybe your follow-up article should state how superstring theory isn't using the right equations because they can't be proved, come on edittors, you can be a little more creative than that.
Heh - maybe the Russians ran across a group of Western European tourist's kids & their Aibos out for a walk :)
you arent actually "looking around in the wrong places".. decoding of radio-signals has found quasars, and some other anomalies in space.. not *everything* has to be about BEM's does it?
Maeryk
Feminine Protection? What is that? A chartreuse flame thrower?
Project leader Professor Paul Horowitz, of 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.
"In other words, interstellar laser communication is altogether practicable.
So we can communicate by shooting a really strong laser at nearby stars?
I can just see it now... "We come in peace!" ZAAAAAP!
Since the photon emissions from a star are in a random fashion with regard to time, photons from a star usually hit only one of the sensors at a time. The idea is that if a laser pulse was fired at Earth for a few nanoseconds, the detectors would simultaneously receive many photons in the same few nanoseconds, which would be out of the ordinary for normal stars.
The interesting thing about Optical SETI is that you don't necessarily need a massive telescope to do it. Since the HW only cares about multiple photons in the same time frame, it doesn't matter much how precise your telescope is, just how precise your HW and detectors are.
Einstein says "nope." The speed of light in a vacuum ("c") is asymptotic according to general relativity; things starting out slower than c will never exceed it. Interestingly enough, relativity also allows for faster-than-c particles, but they would never be able to drop below c. Welcome to physics. :)
-Legion
-Legion
"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 Simpsons episode comes to mind...
"We'll just cover you with rum and nobody will believe you!"
---
IMO man will never discover alien intelligence in the heavens because he doesn't really want to fidn it. If he did, he wouldn't dismiss the examples right here on earth.
It took 10 years of fighting to get much of the scientific community admit thatour higher ape relatives (chimps, gorillas, and such) possess all the fundemental intellectual capability of about a 5 year old human child. The fight over ape-signing being communication was the focal point of the debate and at the same time the defining exampel of this humanocentric bias.
Even more amazing, wild porpises have shown all the same basic behaviro patterns as humans (including social touchign and recreational sex, as an aside.) There have alsoi beene xperiments with porpises that **stringly** suggest they have their own fairly sophisticated language.
To admit we aren't alone woudl be to admit we aren't unique. That we are just one of countless natural variations on life, no better or worse then any other. This last bit of humano-centricity, that somehow we are "not animals" is a hard thing for many people to accept, even many "objective" scientists.
As Contact pointed out, anyone within about 60 light years probably already knows we're here, and anyone within 30 years has had time to send a message back. Since they know exactly where we are, they could use laser for the message, and save on power costs.
We should be watching every star within 31 light years, and gradually widening our search.
...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?
:) ), and how do we know that every life form would use SOUND as communication?
We came up with radio for the transmission of sound (at least, if I am wrong about that, don't kill me
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.
--Fesh
--Fesh
Kill -9 'em all, let root@localhost sort 'em out.
But you are right, by eavesdropping in this way there is a very high chance that any signal we detect will be (almost?) impossible to decipher. If they aren't trying to be universally understandable, they probably won't be understandable at all, except to somebody who knows the format.
OTOH, there is a very significant piece of information which will be obtained from the mere existence of any ET signal - that is of course, that ETs exist, and we are not alone. That would be worth knowing even if (frustratingly) we couldn't understand what they were saying. And if optical SETI advocates are right in suggesting that optical communication would be the norm for a spacefaring civilisation, then by all means, let's look in the optical, as it might be our best chance of finding them.
The real Captain Avatar is a fictional character, so I suppose he doesn't mind if I impersonate him.
'Zeelub, stop pointing your laser-pointer at Earth -- you're making the mammals excited.'
I quite agree. However, we must remember that this method can probably only reveal their local (i.e. planet- or planetary-system-wide) communications, but as the idea of detecting other directed intelligence is in itself so fascinating, it could be all we need for a while.
If, however, we want to *communicate* with extraterrestrials or to find an interstellar culture, radio is probably not the medium - and neither are simple pulsed or modulated laser beams - because they're still limited to 3x10^8 m/s and any signals we can receive will therefore only be fossil radio/TV.
But I have a vague memory of an experiment in the late 70s/early 80s, in which a polarising filter was inserted into one half of a split laser beam (A) and used to modify its polarisation. As I remember it, the change in polarisation (or its inverse?) was *instantaneously* reproduced at *all points* along the other half of the beam (B).
Pertinent questions are, what happens to the original beam before the splitter, how is beam B affected if the change in polarisation only affects a small part of the cross-section of beam A, what happens if the beam is not continuous, but pulsed and/or modulated in some way, and what happens in beams 3-n if the parent beam is split into more than 2 parts (by a single multi-way splitter, obviously)?
Imho, this does seem to offer a reasonable shot at interstellar communications. Once we send a mission, let's say to the Sirius system - it's only 8.7 light years away - all we do is set up a permanent laser link to Starbase Sirius, simply start switching the beam polarity and wait 17.4 years for their reply.
If it would work for us, it would work for Them. So, wouldn't it make more sense to look at changes in the polarity of coherent light in space?
"If I have seen less far than others, it is because Hal Abelson was standing on my shoulders."
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?
Yep, I never spell check.
More incorrect spellings can be found he
Remember, guys, we're just getting started. There's the whole electromagnetic spectrum to search, and thousands of nearby stars to aim telescopes at. With limited resources, searching in the radio bound near the water hole seemed like a good place to start because radio signals travel throughout the Galaxy and the water hole is relatively quiet and is near a major landmark (the H I line).
We're just starting here. Even if the Galaxy is buzzing with alien civilizations, it may be a while before we find them. We have to find the right frequency.
max
This article is a perfect example of why i gave up reading cnn a long time ago. The article starts off innocently enough describing the various aspects of the story, yet ends with a completely irrelevant blurb about how a "russian news agency" reported on an alien visitation in some soviet city more than ten years ago. what the point of mentioning that was, was entirely lost to me.
the art of cold war propaganda is alive and well.
Funny you mentioned that. I was actually living in Spain that year and I clearly remember the story about the humanoids in Russia story being mentioned on a "News Break!"
They didn't say anything else later in the news that day.
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"?
And by the way... we're listening, but are we transmitting? Is our usual EMF noise enough to clue an alien race in?
--
SO YOU'RE GOING TO DIE: The Comic for Dealing with Death
StarWars/SETI - communicate with aliens and blow up ICBMs!
He was obviously talking about building a tunnel of air from their home planet to Earth and then communicating using sound waves.
Just because we need water, oxygen, light etc. doesn't mean there can not be something out there thriving on any element you wish in any environment imaginable. It's not like we have a lot of empirical evidence in the E.T. area.
First of all, not to complain or anything, but we still don't know enough about the natural universe to have any clue whether a billionth-of-a-second-long pulse of coherent light is natural or not.
Oh, no! I hope this experiment doesn't tell us more about the natural universe!
"It's almost like they're pointing a flashlight straight at us!"
"That's a star, sir"
The idea is not that they would be trying to communicate with us, but rather we would detect very old traces of aliens communicating with each other.
Here is something I've always been curious about:
/. there was a story about a researcher getting particles to travel faster than the speed of light. The odd thing about this is that if we have some idea that this is possible and we are trying to talk to a civilization with greater intelligence than us, wouldn't they probably use this technology.
Not too long ago, on
I mean really, isn't the speed of light just a little too slow for your average space faring cell phone.
So what does everyone think? Do I remember my stories correctly? Is my physics sound?
What I'm picturing is one day we build a receiver for these faster than light signals, and we suddenly start to pick up all the alien communication signals buzzing around.
---Lane
What's the point of moderating?!
There's a flat 200 meters from where I live, direct line of sight, it has a window and I see light when it's dark, about 12 the light is turned off, almost everyday.
Thinking about it, I got to the conclussion that there's some kind of intelligent life there (how clever!)
The point is that, I know someone lives there, but I will never be able to communicate with that someone because he/she is not aware of my presence, and we are 200 meters apart, too much.
Just think how impossible is to establish some kind of communication with an alien, living millions of light-years (or is it years-light?) away from us, so talking to an alien is impossible given the universe we live in, the limited speed of light is a big constrain.
Anyway, I have a SETI client installed; the fact that I know I have a neighbour living 200 meters away doesn't change anything, but it certainly would change things if I had the confirmation that there is intelligent life somewhere (oh! wait! there is intelligent life on the earth!).
Photons *are* quantum particles (inasmuch as a photon is just the manefestation of a string at a certain frequency).
--
Soma: because a gramme is better than a damn.
It starts by being relatively coherent and talking about contacting distant civilizations. Then, out of nowhere, they throw in "The possibility that aliens from other worlds make visits to Earth has been the subject of speculation for years in films like ET and Close Encounters of the Third Kind," a statement that has nothing to do with SETI. Then there's two more ontopic sentences, and finally the article ends with:
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.
Sheesh. It's not only subliterate but also a complete misrepresentation of what SETI is about.
I disagree...with a sufficiently long message, and all other things being equal, it is no more or less difficult to determine how to reconstruct a message from a technical standpoint, whether that message is encoded digitally or in analog. ALL formats are completely arbitrary to someone who has no idea what you are trying to communicate. Consider, for example, analog NTSC television signals....there are many channels of data encoded in a "single channel": horizontal, vertical, color, sound, SAP, frame timing data, and captioning. And there are dozens of neighboring stations in the spectrum. And right next door is FM. And right next to that is cellular, CB, etc. Since a given TV signal is spread all over the place, how do you, a priori, determine where to start hacking the signal up? Which subsignals do you associate with each other?
It is a much more difficult problem when you have NO IDEA where to begin.
Can someone who knows the math tell us something about this? I would think you'd want the beam to cover the entire solar system of the target star, or at least the inner planets, where a technological society would be more likely to live. What size of physical laser are we talking about here?
TheFrood
If you say "I'll probably get modded down for this..." then I will mod you down.
Harder to decypher, but easier to detect. But if we don't detect anything, there's nothing to decypher, anyway. First things first.
If we detect some laser pulses aimed at us, we can then start looking for other, different signals from the same source. And funding would be easier, because instead of conducting a search for something that may or may not exist, we would be further investigating something that is known to exist - even if it turns out to be a natural phenomenon. We would know roughly what strength radio signals we would be looking for, and thus what size radio-telescope to use/build.
You could almost see the laser light as the phone ringing, telling us where to look for the radio message.
If we're just meat, then they are toasters.
I always used to call Data on ST:TNG "the toaster," which pissed off my wife. It's my preferred racial slur for intelligent machines.
"Sir, we have intercepted an alien recon pod."
"And?"
"It's full of toasters."
"Toasters?"
"Yes sir, small, chrome-plated machines with simple moving parts and heating elements."
"You're telling me that toasters dropped a rock on New York?"
"That is the lab's unfortunate conclusion, sir."
[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."
I think SETI is a dumb idea. I mean, it's possible that: 1) There is no life out there to talk to. 2) They use a form of communcation beyond our ability to work with. 3) Perhaps we're the smartest race in all the universe, so we're looking to communicate with creatures that haven't evolved to the correct intelegence level yet.
Go here for teh [sic] funny.
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
Its probably a good idea to scan the sky for almost any type of un-natural signal.
Atticka
No sig here...
make as much noise as possible, what if other beings are listening for us? Along with listening we should be making some noise our selves, and lots of it. It might spark a response from some civilization to tell us shut the hell up!
No sig here...
If I was on something like this for a long time and sudden found out that it was a complete waste, becuase of looking in the wrong place, I would be very pissed. But, as the article says, might be looking in the wrong place. We'll just have to wait and see.
until (succeed) try { again(); }
until (succeed) try { again(); }
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.
...This paper (if one can call it that) is just plain silly. I especially liked his use of Scientific terms such as "Super-Fast"
I am become Troll, destroyer of threads
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
I don't know about you, but I think any conversation that takes 1000 years to get a reply isn't exactly practicable. The message would only be transmitted at the speed of light, which could take thousands of years to get here, depending how far away they were, then another few thousand for us to reply. I guess it would still be faster than the postal system.
It's a 7.
Go ahead. Prove me wrong. :)
Bugrit! Millenium hand and shrimp!
Another element is that some forms of encryptions are designed to make your data look indistinguishable from noise. Granted that in certain situations (such as politics) this is a naturally occuring phenomena. But in any case, this make detection much more difficult.
Think of space aliens trying to decode all of those encrypted transmissions that we might be seeing from HDTV in a few years. it certainly would not show up in the clear.
Now we try to apply this to projects like SETI. We might have any number of very bright "noise" sources that are actually quantum transmitters for the Server planet of the Western Galactic Gamers Conglomerate (or whatever). and because we haven't paid our subscription fee, we do not get in to play the game.
Needless to say, we would have a long time trying to decode the transmission.This is without even hazarding a guess about what galactic politics is like. We could be in a back water that recently got wiped by some sort of war. We could be in some one's nuetral zone. etc etc etc
the possiblities are endless.
"It is a greater offense to steal men's labor, than their clothes"
which civillization will be so stupid to use light to cummunicate in open space??!!
We don't (and we humans are quite stupid).
Of which you are a good example of (stupid, that is). We humans DO use light as a form of communication. We need light to see, and to help form words on paper, by the act of absorption and reflection...
I actually had a high school final English exam which featured this story[ about 8 years ago]._ _______
__________________________________________
_________________________________________________
"What's impossible today is normal tomorrow."
Huh? Apropos what?
My assumption is that the intelligent species out there aren't advertising their presence.
Interesting assumption. Too bad the only example we can test it against in the universe (ie, humans) violates it. (Let's put arguments of humans being "intelligent" aside!) We make no attempt to hide our presence. It's pretty conceivable to me that other species could make the same "mistake".
Anyone worth contacting is probably dangerous.
Now that might be true. But let's find the signal first and decide later if we want to contact them. The discovery of other life, dangerous or not, will be fantastic and change our point of view forever. Not to mention, we might learn a tidbit or two from their signal.
Even if they did, laser based communication is likely to be line of sight so any aliens using this technology will be aiming the beams at their detectors. For us to detect the beam either they'd have to miss and hit us accidentally, or we've got to be within the spreading path of the beam behind the target, or we've got to detect it reflected off interstellar dust or something (which would radically reduce it's brightness).
San Jose? Don't they have bigger fish to fry right now?
Maybe they should build a telescope to look for power.
TK
Well, why don't we just look for little green men on mars, we'd have a better chance of finding intelligent life there, anyway... And while we're on the subject, we need to search for other intelligent life, because there is none on this planet to speak of.....besides us geeks that is...=)
So now we've got plans to look for intelligent life that sent a message directly to us, to a precise location in the cosmos (that wasn't blocked by a star, planet, gas cloud, etc), during a certain period of time, using a given range of the electromagnetic radiation spectrum, and in a format that we could decipher. Ya right. I'm holding my breath for this one.
i have a problem with the common assumption that worlds like earth that teem with life will spawn a super intelligent species. on our own planet the coming of intelligence was not a given, it was a random effect helped by a couple of well timed asteroids and a relatively stable place in the galactic arm, plus the right amount of radiation. brains are expensive organs and without the dramatic climactic changes that helped proto-humans become dominant most species would not bother with a large complex brain.
insects do quite well without them.
SETI's use of Drake's Equation places f(i) (the number of intelligent species on planets that are already in the right zone and have already spawned life) as 1. this is totally proposterous to me.
--
j u l e s @ p o p m o n k e y . c o m
in this age of communication i'm just not getting through
what does this have to do with seti? yeah, there are plenty of other successful DNA/RNA carriers. plants.... insects.... but they're not going into space...
--
j u l e s @ p o p m o n k e y . c o m
in this age of communication i'm just not getting through
Maybe not signals. Maybe software.
It's a conspiracy to implant software into everyone's computers. You know, the RIAA-at-home client.
I'll see your senator, and I'll raise you two judges.
you made me laugh, thought i'd tell you
"Cornflakes are not the innocent critters they seem"- Sterling Morrison
This has been planned by the Planetary Society for quite awhile. One of their newsletters last year featured optical SETI, in which they went through the computing setup and everything. If you want to know more I suggets you check it out. One more thing: from what I've gathered about the project, it will most definitely not be in opposition to radio SETI, but just another approach. If I recall, one scientist described SETI as "trying to catch fish in a gutter with nothing more than a string...it probably won't work, but it's a start." Maybe optical SETI is just the next step as we work our way out of the cosmic gutter:)
The best way to predict the future is to invent it.
huh? alienses?
If we add up all the data that this new optical telescope over the most complex equations and algorithms that scientists can muster, will we get an answer of....42?
"They believe a technologically advanced race might be more likely to communicate using pulsed laser beams rather than radio. "
So, are they sayingis that "advanced races" use a high tech version of morse code. This raises a problem. This implies that the signal is in some unknown Base (binary being base 2) and is encoded in some unknown format for transmission, possibly encrypted by default.
So, lets assume for the sake of arguement that we do find pulsating light that shows some form of pattern, there is pretty much no chance we would have any idea what it's saying and we would have no ability to respond. At least with basic radio signals, like TV and Radio, you can easily reverse enginner the signal...assuming thats not encrypted too (I remeber watching a discovery show where the kid who invented the TV was watching RCA's transmissions to see how far along they were, before he went public). Thus we would have a better chance of being able to respond to them, if it's a local (100 Light years) species.
Burn Hollywood Burn
--------------------------upSIde dOwn -- umOp apISdn--------------------------
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
One of the Professors in this project was interviewed on Sky TV yesterday, they asked him weather SETI like system was necessary and he replied that due to the fact that this was just one "telescope" there was no need for that sort of size approach - but he noticed seti running on a few journalists PCs on his way though the studio =) .. hehe
--
Jon - TheSpork
Yeah, with all the experience I've had dealing with aliens....I'd assume they use laser pulses to communicate too.
Okay, this is great...
r /e lectromagnetic.html
* Split Infinity Music
First of all, not to complain or anything, but we still don't know enough about the natural universe to have any clue whether a billionth-of-a-second-long pulse of coherent light is natural or not.
After all, "laser" light is a natural phenomenon we have learned how to produce and control at will. It stands to reason it may be naturally produced without any intelligence. If you apply the same "intelligence has just gotta happen sometime" standard used by Carl Sagan, so coherent light oughta happen spontaneously at least somewhere, sometime.
The only reasonable way to PROVE it isn't natural is to detect an intelligent pattern embedded in it.
So here's my question: If you only pick up a signal a few billionths of a second in duration, just how much data can be fit there to prove intelligence?
If you look at the electromagnetic spectrum, and presume they'll be looking for light somewhere near the visible spectrum (which is a bad idea for transmission efficiency anyway), and assume that you have to modulate the "carrier" frequency to transmit some data, I calculate that you could fit at most several tens of thousand of bits in a pulse that short. That sounds like a lot but it may be hard to fit (or in our case FIND) a lot of meaning in that kind of pulse.
A good light primer can be found here:
http://micro.magnet.fsu.edu/primer/lightandcolo
What's wrong with this picture?
* ~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-
--Brandon / Split Infinity Music
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!
That's not a troll, you syphalitic retard. If it was, I would've said we'd be making first contact with your scabby little dick.
Hope this helps.
I think your point here is one that biologists are still debating, whether evolution naturally leads to intelligence. I think there are convincing arguments both for and against the issue; SETI's use of an optimistic number in the equation might irritate those with the opposite viewpoint, but can't yet be disproved. Until that happens, I'm fine with letting them put reasonable numbers in as they wish.
You mean, like this?
http://atrey.karlin.mff.cuni.cz/~clock/twibright/r onja/
or this?
"Lighthouse Communications Inc., Littleton, CO Constructed and tested an optical through-the-air communications system with a 10 mile range. Proposed methods and wrote description of a wide area, high speed information broadcasting service. Service would provide terabytes of library type information to subscribers at high data rates. No FCC approval needed."
http://www.djandassoc.com/projects.html
or, like this?
http://www.fas.org/spp/military/budget/peds_98a/06 03006a.htm
(and we humans are quite stupid).
Speak for yourself.
The ammount of power needed to trasnmit data through a light beam in open space is really big,
No, it isn't.
turning the whole process whortless.
Lasers can removed "whorts," too.
That's why we use laser light in a restricting environment (aka optic fiber). Sorry, but it's the worst use for a telescope I could ever imagine....
Laser light communications holds great promise for providing high bandwidth, line-of-sight communication between points that cannot be spanned by cable. A few years ago, some astronomers pinged a laser modulator off the Galileo space probe when it passed near Earth. If Galileo had been equiped with an optical demodulator, it would have been able to decode our signals as it zipped by at thousands of miles an hour.
See also:
http://www.spie.org/web/abstracts/1400/1417.html
or
http://www.spie.org/web/abstracts/1800/1866.html
"In the Galileo Optical Experiment (GOPEX), optical
transmissions were beamed to the Galileo spacecraft by
Earth-based transmitters at Table Mountain Observatory
(TMO), California, and Starfire Optical Range (SOR),
New Mexico. The demonstration took place over an
eight-day period (December 9 through December 16) as
Galileo receded from Earth on its way to Jupiter. At 6
million kilometers (15 times the Earth-Moon distance),
the laser beam sent from Table Mountain Observatory
eight days after Earth flyby covered the longest known
range for laser transmission and detection.!"
Taking stuff apart since 1969 (TM)
The problem with this is that we're still looking for signals that are FAR TOO SLOW to be useful. If there are sentient lifeforms out there traveling the universe, they _MUST_ be able to both travel _and_ communicate faster than the speed of light. This is not to say I can think of an alternative.
Too bad we don't have anything to work with in the faster-than-light-travel department. I wonder if that MIT experiment where they slowed and stopped light had any luck accelerating it...
-k.
The Harvard group postulates that we are much more likely to be contacted by aliens via laser, or other tight-beam system, as the narrower beam width would require less power (makes more effiecient use of power). This theory is right on the money--if the aliens are deliberately trying to contact us. Much more likely, however, is that we would pick up extraneous signals intended for their own use. For those who have seen Contact, think about how the otherworlders discovered us--they picked up the first signal we radiated into space with any significant power. We weren't trying to contact anybody, just send TV across the ocean; that the signal was radiated into space was merely a consequence of using radio as the method of transmission. Because radio signals tend to scatter, especially on that older technology, the signal was radiated in all directions, including "up." Detecting that accidental emission, the aliens determined that there was life on our planet. It is less like communication (a deliberate two-way discourse), and more like Signals Intelligence (SIGINT). And (don't all raise your hands at once) who knows who the leader in SIGINT is? The NSA! Odds are, the NSA is going to discover the signal before SETI, NASA, or any others. I don't mean to suggest that they will discover life--in my opinion, that is highly unlikely, simply because those aren't the types of signals NSA looks for--it would likely be chalked up as noise, and they would go back to monitoring Chinese satellite traffic. I am only saying that they would likely be the first to receive (detect) the presence of the signal. It would have to be analyzed in the proper context (enter SETI) to be recognized for what it is. The ultimate dream system for SETI would be to use the Areciebo (sp?) dish, the VLA, etc, as well as NSA's resources, use NSA's signal-detection and -processing systems, then use their own analysis tools. Imagine what a powerful combination that could be!
The point here is that we are far more likely to detect an alien civilization by listening for spurious emissions (SIGINT) than by searching for signals deliberatly aimed at us. In order to detect a laser aimed at us, we would have to examine every star capable of supporting life (same as with SIGINT), but they would also have to aim the signal at us deliberately--that is, they would have to have already detected us and decided to try to contact us. Think about that from their point of view--if you worked for SETI or NASA or others, would you be shining lasers into space to try to communicate with other planets that may or may not have life and may or may not be listening and may or may not even understand what they are looking for? I know I wouldn't, and I'm a supporter of SETI. Realistically, listening for broadcast signals is much more likely to yield results than looking for tight-beam communications.
Incidentally, I didn't bring up the NSA to suggest any sort of conspiracy, just to discuss the equipment differences. And, no, I really don't believe the US Government has been hiding aliens at Roswell for the last 40 years. To almost-quote Dave Barry, it isn't that I don't believe that aliens might have crashed at Roswell, I just don't believe that our government could successfully run a cover-up for that long.
"Make it ten--I am only a poor corrupt official."
--Captain Louis Renault (Claude Rains), Casablanca
I guess my point is, that this isn't as big a deal or as big a leap of thought as it is being made out to be. There is a lot of real estate out there to look in. Ok, its cool, but we had to do this eventually.
Naeser's Law:
Well raise my Rent! Someone is FINALLY going to look in the right place... It's about time... Jamie Walker CEO-Publisher DebateUSA.com
Why isn't earth putting out laser messsages? It's not like they're not looking for us too. In the article, it says that we are able to put out pulses of light to other stars that would appear many times brighter than the sun. So why aren't we?
___ alwaysBETA.com - Hey, you've got nothing better to do.
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?
SETI is a privately funded organization that can only cover 1% of the sky at a time.
For all of you thinking that "Well why not use a laser?" the answer to that is that is WHY THE HELL WOULD YOU WANT TO COMMUNICATE WITH THIS LITTE WORTHLESS MUDBALL? A laser would be too confined to one area why the hell blow a few million trying to pick up a laser pulse that no one would even bother sending to us?
We are looking for radio waves because they spread out over a great area and they are probably the most crude way of communicating over large distancess. Think what you want but don't go assuming that the program is completly lame by looking for radio signals.
I do not think aliens would use a laser to communicate. The laser would have to be fired directly at the target. A civilization that was located 100 light years away from our planet would be firing at a target 12000 miles in diameter from a distance of 586,971,360,000,000 miles. That means the laser would have a window of 2.64953E-05 arcseconds to actually be seen by anyone here. Factor in that we are moving at a great rate around the sun, which is also moving relative to the other stars in the local region and it would be almost impossible to effectively use the laser as a communication beacon. In contrast, radio waves propagate radially from the source. This means that with sufficient amplification they can be heard at any time after they are created. Also, a radio station can be operated for thousands of years on the amount of power that would be required to produce perhaps a dozen laser beams which were sufficient to be noticed at such a distance.
Imagine an isolated island where the natives try to establish the existance of other inhabited islands.
They send smoke signals from all the high mountains and look for like back.
As they pronounce the re-affirmation that they are alone there are transcontinental jets flying over their heads, the EM spectrum is full of transmissions and a couple of satelites are presently scanning the island in a number of frequencies.
This poses an interesting problem. Not only do we have to be listening in the RIGHT area of the sky, using the RIGHT frequencies but also the species we try to listen to will have to be at the RIGHT stage of the development. Will we keep listening in Radio when we go to Lasers? Will we keep listening to Radio AND lasers when we move to Gravity waves? etc.While this will be the first optical telescope dedicated to SETI research, the idea of searching for continuous or pulsed laser beacons is not new. It was proposed by Charles Townes and R N Schwartz in a 1961 paper on the subject on inter-stellar laser communication. It's interesting to note that the idea of using laser's for inter-stellar communication is about as old as lasers themselves. Several groups at Berkeley, Harvard and Princeton are working on OSETI projects that operate on a part-time basis, or piggy back on other experiments. There is also an Australian OSETI project underway, as well as several privately operated OSETI observatories. There is a great deal of interesting work being done in optical SETI, with both new facilities and detection hardware under development. The reason for the sudden upswing in interest has a lot to do with the growth of optical communication, and is not a sign that researchers are abandoning the microwave band. The basic consensus is that nobody really knows which signaling format would be preferred (if any), and so we need to look at the largest possible search space. Brian McConnell, Author Beyond Contact : A Guide to SETI & Communicating with Alien Civilizations (upcoming SETI book from O'Reilly & Associates)
A Brief Explanation About Why They Wouldn't
The closest solar system to us that would be able to support life (i.e. large enough to provide an perfect distance from the sun to support the right temperatures) is about approx. 1.5 million light years away (light takes 1.5 million years to reach this galaxy)... So assuming that they had a telescope that could see the surface of our planet what would they see?? Dinosaurs... Why? Because the light from the earth when dinosaurs roamed the earth would just be reaching their solar system now.... So why would they bother coming to a planet to see large animals... Please don't flame this comment for incorrect figures, the theory is correct.....
I'd say it's slim unless mankind manages to get off this rock in the next few millenia and actually manages to colonize other planets or maybe even other solar systems. But that has nothing to do with whether or not extraterrestrial intelligence actually exists. Our universe is filled with galaxies, each filled with star systems, some of which have rather hospitable planets. Some may say that's a pretty ridiculous assumption, that there are other life-supporting planets out there, but the sheer number of other stars makes it rather probable for at least one other planet to be inhabited by a sentient race. So what's all this boil down to? Well I say we shouldn't be thinking about this, at ALL. If for some reason one day humans make contact, it's most likely not going to be in the near future (by that I mean in the next few millenia), and I think it's safe to say it's not going to be because of donated clock cycles. We're approaching this whole situation with a brute-force strategy (keep looking, keep sending messages saying "Hey speak up"..) and I personally doubt that a) We're going to "see" anything, b) Anyone's going to "hear" anything, and c) If they do, they're not going to have the first clue as to who we are, what we want, or what the hell we're saying in the first place. So my solution to this whole problem is to not give the search for extraterrestrial intelligence another thought for another couple centuries or millenia when mankind stumbles on some crazy new technology that'll end up either dropping us on an alien's doorstep or dropping an alien on our doorstep. And that's that.