SETI search shows no signs of intell. life

[badeskov]

oh my... all the acr welders on this planet... and your listening for camp fire songs?

we do not need to hear a talk radio broadcast ... we only need to hear a genarator running , a arc welder... a transmission line with a bad insulator ...

i do not need to hear a language that i will never understand.... i just want to hear something like a voice in the dark of the night sky... that says ... there is anything out there ...

right this moment , there is not any reason to beleive that there is any form of life in space ...

which means... either there is something very special about where we stand.... or there is something special about every where we are not ....

Except that you won't "hear" an arc welder very far out.That said there is plenty of reason to believe that there is life outside of our planet - if we detected it, however, we wouldn't need to believe - we would know.

Cheers,

Badeskov

[Esoteric Toad]

What if the advance aliens do not have ears, communicate via color, movement or smell? This could drastically affect their evolution of communication devices. Color for instance could cause communications to take the form of light up to powerful lasers for interplanetary communication...skipping the radio/microwave communications. I cannot imagine how smell would be handled. If they were aquatic there might be no communication beyond the waters they live in.

I only brought up the point because we tend to think in a very 'human' way about potentially extremely unhuman critters. JMO.

[Space Commander Travis]

oh my... all the acr welders on this planet... and your listening for camp fire songs?

we do not need to hear a talk radio broadcast ... we only need to hear a genarator running , a arc welder... a transmission line with a bad insulator ...

i do not need to hear a language that i will never understand.... i just want to hear something like a voice in the dark of the night sky... that says ... there is anything out there ...

How do you suggest doing that from (even with the stars right next door) several light years away?

[Space Commander Travis]

What if the advance aliens do not have ears, communicate via color, movement or smell? This could drastically affect their evolution of communication devices. Color for instance could cause communications to take the form of light up to powerful lasers for interplanetary communication...skipping the radio/microwave communications. I cannot imagine how smell would be handled. If they were aquatic there might be no communication beyond the waters they live in.

I only brought up the point because we tend to think in a very 'human' way about potentially extremely unhuman critters. JMO.

Well, exactly. once again, look at Dolphins, or bats, or Ants. They might communicate through pheromones, or telepathy.

[Frank Merton]

Actually, pheromones and sound waves are ways humans communicate. Something un-human might be radio, but we found that. It's hard to imagine and probably false to insist that they would use something we have no knowledge of.

Gravity waves and neutrinos exist as remote possibilities, but they would offer no partular advantage over radio and be a lot more expensive.

[Space Commander Travis]

Actually, pheromones and sound waves are ways humans communicate. Something un-human might be radio, but we found that. It's hard to imagine and probably false to insist that they would use something we have no knowledge of.

Gravity waves and neutrinos exist as remote possibilities, but they would offer no partular advantage over radio and be a lot more expensive. {C}

but they woudln't be detecatble over the vast distances of space, is the point. Nor would electromagnetic noise that wasn't specifically directed at us, by a very powerful transmitter.

[Hazzard]

While its interesting to imagine how far our radio signals have traveled into space, its extremely unlikely that an alien planet will be able to catch the latest episode of I love Lucy. This is thanks to the inverse square law. In "English", its a form of signal degradation.

Because of this inverse square law, all of our radio signals become indistinguishable from background noise at around a few light-years from earth.

[AsteroidX]

Our early and current form of comms would be like turning a high powered fan to any ET's trying to communicate along the same frequency. Probably more disruptive and agitating then anything IMO. They likely if they are out there using trans stellar comms can avoid us hearing there comms. Again just IMO.

[mcrom901]

Because of this inverse square law, all of our radio signals become indistinguishable from background noise at around a few light-years from earth.

and what's with the 2nd law of thermodynamics which kaku mentions about... do those energy signatures also dissolve in oblivion?

eta.... ^^ applies to 'type-2' civilizations and i had not recalled it clearly...

"With their energy output comparable to that of a small star, they should be visible from space. Dyson has proposed that a Type II civilization may even build a gigantic sphere around their star to more efficiently utilize its total energy output. Even if they try to conceal their existence, they must, by the Second Law of Thermodynamics, emit waste heat. From outer space, their planet may glow like a Christmas tree ornament. Dyson has even proposed looking specifically for infrared emissions (rather than radio and TV) to identify these Type II civilizations." - http://mkaku.org/home/?page_id=246

Edited April 13, 2013 by mcrom901

[Hazzard]

and what's with the 2nd law of thermodynamics which kaku mentions about... do those energy signatures also dissolve in oblivion?

eta.... ^^ applies to 'type-2' civilizations and i had not recalled it clearly...

"With their energy output comparable to that of a small star, they should be visible from space. Dyson has proposed that a Type II civilization may even build a gigantic sphere around their star to more efficiently utilize its total energy output. Even if they try to conceal their existence, they must, by the Second Law of Thermodynamics, emit waste heat. From outer space, their planet may glow like a Christmas tree ornament. Dyson has even proposed looking specifically for infrared emissions (rather than radio and TV) to identify these Type II civilizations." - http://mkaku.org/home/?page_id=246

Or what about a,... Type III "A civilization in possession of energy on the scale of its own galaxy, with energy consumption at ≈4×10⁴⁴ erg/sec." Lemarchand stated this as "A civilization with access to the power comparable to the luminosity of the entire Milky Way galaxy, about 4 × 10³⁷ Watts."

[Frank Merton]

but they woudln't be detecatble over the vast distances of space, is the point. Nor would electromagnetic noise that wasn't specifically directed at us, by a very powerful transmitter.

It depends on how advanced a society it is. Our radio if feeble, but if we wanted to talk (talk isn't really the word -- transmit information) to a large distributed culture, it would be powerful enough that we would detect it.

[Frank Merton]

The more I think about it the more persuaded I become that the reason they aren't out there and haven't been here is that at some point everyone discovers inner space (perhaps just virtual realities but perhaps some technology that involves having one's own dimensions).

Another possibility is they all become traditional Buddhist monks -- now that would shut down science fast enough.

[Lilly]

...Actually, to the best of my knowledge Drake's equation suggests no such thing. Drake's equation is merely a probability spelled out and whatever it suggests is solely based on the numbers stuffed into it. Numbers we can currently only offer guesses towards.

Correct, the Drake Equation is a formula that allows one to figure probability based on various factors that could lead to intelligent civilizations. Much of the equation's variables are simply guess work due to our not having specific information. In others words, the Drake Equation just allows us to make an "educated guess".

[Frank Merton]

I must admit that I have always looked at the Drake Equation as a waste of time: an attempt to link an illusion of precion to something where precision is impossible. One can even question whether or not he has adequately captured all the variables.

[Tutankhaten-pasheri]

And all the equipment that is used for SETI, it is trained on the cosmos, and not at Earth? I simply wondered is all, about not detecting any intelligent life.....

[Just Dave]

Mah... If it could happen on this planet it could happen anywhere else.. life that is..

[seeder]

I must admit that I have always looked at the Drake Equation as a waste of time: an attempt to link an illusion of precion to something where precision is impossible. One can even question whether or not he has adequately captured all the variables.

As said already, Drakes EQ is a set of assumptions and has its critics..

Criticism

Criticism of the Drake equation follows mostly from the observation that several terms in the equation are largely or entirely based on conjecture. Thus the equation cannot be used to draw firm conclusions of any kind. As Michael Crichton, a science fiction author, stated in a 2003 lecture at Caltech:[37]

The problem, of course, is that none of the terms can be known, and most cannot even be estimated. The only way to work the equation is to fill in with guesses. [...] As a result, the Drake equation can have any value from "billions and billions" to zero. An expression that can mean anything means nothing. Speaking precisely, the Drake equation is literally meaningless...

Another objection is that the very form of the Drake equation assumes that civilizations arise and then die out within their original solar systems. If interstellar colonization is possible, then this assumption is invalid, and the equations of population dynamics would apply instead.[38]

One reply to such criticisms[39] is that even though the Drake equation currently involves speculation about unmeasured parameters, it was not meant to be science, but intended as a way to stimulate dialogue on these topics. Then the focus becomes how to proceed experimentally. Indeed, Drake originally formulated the equation merely as an agenda for discussion at the Green Bank conference.[40]

http://en.wikipedia....ation#Criticism

Over and above all that tho, SETI and its ambitions, while all good and positive, have barely scratched the surface of the search. When you think, that there are more planets and stars than every single grain of sand on all the beaches of the world, and then some...(try to picture that), then our searches and the distance they travel probably equate to half a teaspoon or less of the same sand. In fact probably lots less...

Heres a good read:

Why The SETI Project Is Doomed To Fail: A Radio Engineer's Perspective On The Project And Its Prospects

Lets begin by examining the basics, for those of you with a non-technical background. For a radio circuit to be established, it is necessary to generate a signal, transmit that signal through space, recieve that signal in a reciever sensitive enough to perceive that signal amidst the "noise" (self-generated interference) that every receiver generates, or the radio noise that comes from natural cosmic sources (or, in some cases, man-made noise). That noise has to be overcome by making the signal strong enough to overpower the inherent noise of the receiver, which is the result of the laws of physics and can be minimized to some degree, but not eliminated. Additionally, the farther the signal travels through space, the more of it is lost through spreading out - a problem called "path loss." It is why distant headlights are more faint than close ones. So a communications circuit, whether man made or one being conducted with extraterrestrials, has to overcome these two problems - receiver noise and path loss.

http://www.bidstrup.com/seti.htm

and just to rain on the parade.. (or offer alternative views)

Aliens can't hear us, says astronomer! Fainter broadcasting signals and digital switchover mean Earth will soon be undetectable to extraterrestrials

Human beings are making it harder for extraterrestrials to pick up our broadcasts and make contact, the world's leading expert on the search for alien life warned yesterday.

At a special meeting on the search for extraterrestrial intelligence (Seti), the US astronomer Frank Drake – who has been seeking radio signals from alien civilisations for almost 50 years – told scientists that earthlings were making it less likely they would be heard in space.

Astronomers assumed that a standard technique for any alien intelligence trying to pinpoint other civilisations in the galaxy would involve seeking signals from TV, radio and radar broadcasts, Drake told the meeting at the Royal Society in London.

Scientists on Earth have been using this method, without success so far, to find evidence of intelligent aliens. The theory is that elsewhere in the galaxy other civilisations would probably be doing the same.

An example of this interstellar eavesdropping is dramatised in the Jodie Foster film Contact. Based on a novel by the US astronomer Carl Sagan, it tells the story of an alien civilisation that makes contact after picking up TV broadcasts from Earth.

"The trouble is that we are making ourselves more and more difficult to be heard," said Dr Drake. "We are broadcasting in much more efficient ways today and are making our signals fainter and fainter."

http://www.guardian....r-us-astronomer

.

Edited April 13, 2013 by seeder

[badeskov]

As said already, Drakes EQ is a set of assumptions and has its critics..

Criticism

Criticism of the Drake equation follows mostly from the observation that several terms in the equation are largely or entirely based on conjecture. Thus the equation cannot be used to draw firm conclusions of any kind. As Michael Crichton, a science fiction author, stated in a 2003 lecture at Caltech:[37]

The problem, of course, is that none of the terms can be known, and most cannot even be estimated. The only way to work the equation is to fill in with guesses. [...] As a result, the Drake equation can have any value from "billions and billions" to zero. An expression that can mean anything means nothing. Speaking precisely, the Drake equation is literally meaningless...

Another objection is that the very form of the Drake equation assumes that civilizations arise and then die out within their original solar systems. If interstellar colonization is possible, then this assumption is invalid, and the equations of population dynamics would apply instead.[38]

One reply to such criticisms[39] is that even though the Drake equation currently involves speculation about unmeasured parameters, it was not meant to be science, but intended as a way to stimulate dialogue on these topics. Then the focus becomes how to proceed experimentally. Indeed, Drake originally formulated the equation merely as an agenda for discussion at the Green Bank conference.[40]

http://en.wikipedia....ation#Criticism

Over and above all that tho, SETI and its ambitions, while all good and positive, have barely scratched the surface of the search. When you think, that there are more planets and stars than every single grain of sand on all the beaches of the world, and then some...(try to picture that), then our searches and the distance they travel probably equate to half a teaspoon or less of the same sand. In fact probably lots less...

Heres a good read:

Why The SETI Project Is Doomed To Fail: A Radio Engineer's Perspective On The Project And Its Prospects

Lets begin by examining the basics, for those of you with a non-technical background. For a radio circuit to be established, it is necessary to generate a signal, transmit that signal through space, recieve that signal in a reciever sensitive enough to perceive that signal amidst the "noise" (self-generated interference) that every receiver generates, or the radio noise that comes from natural cosmic sources (or, in some cases, man-made noise). That noise has to be overcome by making the signal strong enough to overpower the inherent noise of the receiver, which is the result of the laws of physics and can be minimized to some degree, but not eliminated. Additionally, the farther the signal travels through space, the more of it is lost through spreading out - a problem called "path loss." It is why distant headlights are more faint than close ones. So a communications circuit, whether man made or one being conducted with extraterrestrials, has to overcome these two problems - receiver noise and path loss.

http://www.bidstrup.com/seti.htm

and just to rain on the parade.. (or offer alternative views)

Aliens can't hear us, says astronomer! Fainter broadcasting signals and digital switchover mean Earth will soon be undetectable to extraterrestrials

Human beings are making it harder for extraterrestrials to pick up our broadcasts and make contact, the world's leading expert on the search for alien life warned yesterday.

At a special meeting on the search for extraterrestrial intelligence (Seti), the US astronomer Frank Drake – who has been seeking radio signals from alien civilisations for almost 50 years – told scientists that earthlings were making it less likely they would be heard in space.

Astronomers assumed that a standard technique for any alien intelligence trying to pinpoint other civilisations in the galaxy would involve seeking signals from TV, radio and radar broadcasts, Drake told the meeting at the Royal Society in London.

Scientists on Earth have been using this method, without success so far, to find evidence of intelligent aliens. The theory is that elsewhere in the galaxy other civilisations would probably be doing the same.

An example of this interstellar eavesdropping is dramatised in the Jodie Foster film Contact. Based on a novel by the US astronomer Carl Sagan, it tells the story of an alien civilisation that makes contact after picking up TV broadcasts from Earth.

"The trouble is that we are making ourselves more and more difficult to be heard," said Dr Drake. "We are broadcasting in much more efficient ways today and are making our signals fainter and fainter."

http://www.guardian....r-us-astronomer

.

I would like to add my sad two cents to this. In my honest opinion, one cannot critique the Drake equation unless one has an issue with the number of factors in it. It is merely a probability equation. What one can critique is the values put into it. Just like one can't really critique a mortgage calculator, whereas one can critique the numbers entered into it.

Cheers,

Badeskov

[DONTEATUS]

I would like to add my sad two cents to this. In my honest opinion, one cannot critique the Drake equation unless one has an issue with the number of factors in it. It is merely a probability equation. What one can critique is the values put into it. Just like one can't really critique a mortgage calculator, whereas one can critique the numbers entered into it.

Cheers,

Badeskov

Hey Badeskov`s was that your toy zappin that Drone last week ?

[Occams Razor]

Actually, to the best of my knowledge Drake's equation suggests no such thing. Drake's equation is merely a probability spelled out and whatever it suggests is solely based on the numbers stuffed into it. Numbers we can currently only offer guesses towards.

True, Drakes "equation" is an estimate based on probability, based on Drakes personal opinion. But the figure of 10,000 civilizations is what Drake comes up with himself when he 'stuffs in' his figures.

Yes and no. Given that electromagnetic radiation is, to the best of our knowledge, one of the most efficient means to do radar and long distance communications over spans where it is not viable to put down different infra-structures (optical fibers, for instance), we should still expect they would radiate in certain wavelength bands. However, that is not to say that we can detect them. Our TV/radio broadcasts are essentially drowned out in noise by the time they leave the Solar system Some high power emitters such as the Ballistic Missile Early Warning System (BMEWS) should be detecable out to a couple of hundred light years, but as they are frequency hopping and doing all kinds of other tricks to avoid jamming, I am sure ET would be rather annoyed trying to home in on it.

Yes, BMEWS is a UHF "frequency hopping" radar system, but the spectrum of the hopping is quite narrow, I believe it's no more than 500khz. This sort of bandwidth on a 425mhz signal is nothing really, this frequency hopping and the patterns in the pulse width and repetition rate would still indicate a synthetic signal generated by a device, which is all that's required when looking for a technologically advanced alien species. I doubt the BMEWS signals would be detectable at a couple of hundred light years though. The sort of thing that is far more likely to be noticed by ET's version of SETI is the 3 terawatt ERP radar from Aricebo used for planetary surface mapping.

All radio emissions would follow the inverse square law, meaning that the power at a given distance would P_z ~ P₀/zs. In other words, each time distance is increased by a factor of 10, the power that can be detected is reduced by a factor of 100. Thus it does not take long before any signal is buried in back ground noise.

True, but SETI have heard what they consider good candidate signals in the past.

Agreed, they have some pretty good equipment, but I am actually not surprised that they have not detected anything yet.

Indeed, especially when you consider they only looked at each of the 86 extra solar planets for 5 minutes each, and they only looked at frequencies within the "water hole"... between 1.4 and 1.7ghz. I think this suggests that what they're really hoping for is an alien species that want's to be detected and is radiating a high power beacon in the "water hole" between the hydrogen and hydroxyl spikes in the microwave noise floor. The beacon would also have to be radiated in the galactic plane, a loud deliberate shout hello. Any aliens doing the same sort of search are not going to see the BMEWS transmissions, in fact they're going to see what we're seeing, nothing. Their equipment could of course be a lot better, they could be looking at a much larger chunk of radio spectrum, one that could include the 425mhz BMEWS transmissions, and their signal processing could be orders of magnitude better than ours.