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No Intelligent Aliens Detected In Gliese 581

timothy posted about 2 years ago | from the beam-me-sideways-this-time dept.

Australia 239

astroengine writes "Using an Australian very long baseline array (VLBA) of three radio antennae, the first very long baseline interferometry (VLBI) campaign has been carried out on a SETI target star: the famous Gliese 581 red dwarf. However, after 8 hours of observing the star — thought to play host to six exoplanets, two of which are in the star's 'habitable zone' — no alien signals were detected. This result isn't surprising, as the likelihood of us stumbling across intelligent aliens living in the Gliese 581 system transmitting radio is extremely slim, but it does validate VLBI as a very exciting means of using the vast amount of exoplanetary data (coming from missions such as the Kepler space telescope) for 'directed SETI' projects."

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Are you guys stupid or something? (-1, Troll)

rab777hp (2543164) | about 2 years ago | (#40196309)

You have to wait another 20 years for a reply.... if it's 20ly away something traveling at C will take 20 years to get year... sure they'll have just gotten our signal, but even if they immediately send out a reply it takes another 20 years, idiots.

Re:Are you guys stupid or something? (1)

Anonymous Coward | about 2 years ago | (#40196323)

Earth is constantly broadcasting. Sure, it's meant for other humans on Earth, but we don't exactly shield it from going into space.

The hope is that aliens with similar technology would put off similar amounts of detectable EM.

Re:Are you guys stupid or something? (1, Redundant)

gmuslera (3436) | about 2 years ago | (#40196415)

The problem is how distingishable was most of it from background noise just outside the solar system, or 20 light years away, even if you are trying to focus what comes from here specifically.

Anyway, if what we send away are our tv shows, they will conclude that here there isn't intelligent life too.

Re:Are you guys stupid or something? (1)

symbolset (646467) | about 2 years ago | (#40196565)

I would think they should be looking for ion engine signatures. That seems a more likely signal to span the distance.

Re:Are you guys stupid or something? (3, Interesting)

beckerist (985855) | about 2 years ago | (#40197087)

Not that magnetohydrodynamic drive exhaust is undetectable but from my understanding, the only way we'd ever see a "signature" is if the engine were pointing directly at us. Given our size, constant movement, and the minuscule amount of ions actually released the probability of ever detecting anything is probably infinitely close to zero.

Re:Are you guys stupid or something? (0)

Anonymous Coward | about 2 years ago | (#40197255)

I think they should be looking for porn of any kind in the universe, now that would definitely show intelligent life.

Re:Are you guys stupid or something? (2)

hairyfeet (841228) | about 2 years ago | (#40197073)

Actually we are broadcasting VERY little now, and most of what we are transmitting won't leave our own system. this is why if other life exists its gonna be hell to catch a signal as there is a very small window between finding out how to broadcast and switching to digital, if other life follows a similar pattern.

Re:Are you guys stupid or something? (5, Informative)

RubberDogBone (851604) | more than 2 years ago | (#40197369)

This is true. Nearly all of what we have ever broadcast has been trashed into junk RF by the time it passes through our own heliopause. Voyager 1 and 2 are helping us learn that it is a fantastic filter aggressively scrubbing and sterilizing radio. Perhaps only a few terrifically strong military radar signals or intentional interplanetary signals (i.e. the powerful Arecibo transmissions) might have made it through. Decades of TV and radio have not. For practical purposes, our Sol system is silent. We are not emitting potent enough repeating signals of the sort we ourselves are seeking.

It is logical to expect a similar result for other planetary systems where something like a heliopause exists. RF would be trashed and never make it into interplanetary space.

For even more discouragement, remember that most of life on Earth does not use radio. A planet teeming with life might yet have nobody emitting even weak signals. Radio derives from the human need to communicate, constantly. Especially while driving. It is entirely possible that another similarly advanced species might not have that need to talk talk talk and entertain at a distance.

Anyway, the universe is a very big place. It's a long way down the road to the pharmacy, but that's nothing compared to the universe. Most of it is empty. On average, we don't actually exist at all. Sigh.

Re:Are you guys stupid or something? (1)

theshibboleth (968645) | more than 2 years ago | (#40197375)

Even if they switch to digital, they would presumably still be broadcasting. Shouldn't the digital signals have distinctive patterns even if they would be hard to interpret?

Re:Are you guys stupid or something? (3, Informative)

vlm (69642) | more than 2 years ago | (#40197381)

Actually we are broadcasting VERY little now, and most of what we are transmitting won't leave our own system. this is why if other life exists its gonna be hell to catch a signal as there is a very small window between finding out how to broadcast and switching to digital, if other life follows a similar pattern.

"Radio Astronomy" by John Kraus has a section on this topic. Well obviously he predates the digital transition. Not all that surprisingly large scale planetary radar has the best range, but the strongest long term signal used to be the constant (hopefully stable freq) of AM radio transmission carriers. You can integrate the carrier over months I suppose if necessary, detectable long below the data level

Re:Are you guys stupid or something? (0)

Anonymous Coward | about 2 years ago | (#40196339)

This also assumes that if there was intelligent life in Gliese 581 that they would be post industrial revolution. The OP is an idiot, as is Timothy for making this front page.

Re:Are you guys stupid or something? (-1, Troll)

flyneye (84093) | about 2 years ago | (#40196397)

All this assumes that WE are intelligent and others haven't done any better than radio waves for communication. Not likely in a society where Hillary Clinton isn't some homeless meth head begging at an Arkansas off ramp.

Re:Are you guys stupid or something? (-1, Flamebait)

Anonymous Coward | about 2 years ago | (#40196557)

Not likely in a society where Hillary Clinton isn't some homeless meth head begging at an Arkansas off ramp.

If dumb loud treacherous cunts like her were all homeless methheads then something like heaven would emerge.

Remember that bullshit speech she did in the South? Suddenly she had a fake Southern accent. Like being deceitful so obviously is gonna convince them she's trustworthy or something... Thing to remember about these ivory tower liberals is they know so much better than you do and we're too stupid to consider things like that - at least if you ask them.

Re:Are you guys stupid or something? (0)

Paracelcus (151056) | about 2 years ago | (#40196641)

So, I guess that you don't like Ms Hillary? So did your meth lab blow up? or are you into Oxicodone? did I spell that right? Them thar fellas down to the coal mine hates them Clintons too!

(Sarcasm)

Re:Are you guys stupid or something? (0)

Anonymous Coward | about 2 years ago | (#40197019)

So, I guess that you don't like Ms Hillary? So did your meth lab blow up? or are you into Oxicodone? did I spell that right? Them thar fellas down to the coal mine hates them Clintons too!

(Sarcasm)

Bill did his girlfriend and smoked his cigars after.

Re:Are you guys stupid or something? (0)

Anonymous Coward | about 2 years ago | (#40197197)

So, I guess that you don't like Ms Hillary? So did your meth lab blow up? or are you into Oxicodone? did I spell that right? Them thar fellas down to the coal mine hates them Clintons too!

(Sarcasm)

Bill did his girlfriend and smoked his cigars after.

This is all just my opinion and nothing more.

Bill Clinton is one of the only men who can really be excused for cheating on his wife. He gets a pass and he earned it.

She's ... extraordinarily masculine. And a turkeyneck. And shrill. And obsessive. And treacherous. And just ... unattractive. Like some nagging mother-in-law. How could any heterosexual man get a woody from her? ANd if you did get a hard-on from her somehow could you trust her not to bite it off in a fit of pent-up feministic rage?

I suspect theirs is a political marriage only. Totally loveless. Even the daughter Chelsea is just to appeal to American family values. It is just like when kings would marry queens of foreign countries to form an alliance. I think the Clintons just felt they'd get farther in politics with a similar partnership. Since he made president they may have been right.

Re:Are you guys stupid or something? (-1, Troll)

Anonymous Coward | about 2 years ago | (#40196543)

This also assumes that if there was intelligent life in Gliese 581 that they would be post industrial revolution.

They could be alien versions of knee grows. Then they'll never industrialize on their own. They will be primitive and tribal for many millenia unless another race introduces them to technology. Earth knee grows existed for thousands of years longer than whites and never made a sailboat, never domesticated animals, never invented the WHEEL for fuck sake let alone discovering electromagnetism! No reason aliens couldn't be that way.

It's true and you know it. Do your PC duty and mod this down now. Even tho it's true!

Re:Are you guys stupid or something? (0)

snappyman (2653559) | about 2 years ago | (#40196341)

Are you a bootynude or something such as that!?

I will reveal such true ferocity without a single problem along the way!

Re:Are you guys stupid or something? (1)

Cazekiel (1417893) | about 2 years ago | (#40196347)

It's more about detecting existing signals, rather than waiting for a reply to ones we JUST sent out. I think they know what they're doing and don't need to drop by /. articles with our comments for confirmation of their methods

Re:Are you guys stupid or something? (3, Informative)

silentcoder (1241496) | about 2 years ago | (#40196357)

Erm... do you even know what SETI is ? Or the concept of a round-trip ?

1) If we had sent a signal, it would take 20 years to get there, and we could expect a reply in no less than 40 years. Twice your estimate.
2) That doesn't actually matter however since we didn't send a signal at all. All we did was listen for signals coming from there. In other words - we were hoping maybe they sent us a signal 20 years ago - or more likely just generally sent out a signal in case *anybody* answers, or even more likely that we could catch a listen-in on a signal that was never intended for outsiders to begin with. If an alien race has satelite television - then any of the beamed-up signals that don't quite hit the target keeps going through space - SETI is really about trying to pick up any that may have come our way.

The most likely result we could get from SETI would probably be accidental signals - on the basis that any aliens running a seti project is most likely to get such signals from us (we sent a lot of signals into space, none of it is actually intended for alien consumption).
A signal intending to be picked up by other species (as in Sagan's Contact) would be a bonus.

That is actually the biggest problem I have with SETI. We're just listening hoping somebody else is bothering to talk or we pick up some stray signal. Truth is, we may well end up in a situation where half a dozen intelligent species are doing the same. All listening to space, waiting for the other one to actually say something.

Re:Are you guys stupid or something? (3, Informative)

kasperd (592156) | about 2 years ago | (#40196823)

we sent a lot of signals into space, none of it is actually intended for alien consumption

One could argue that the Arecibo message [wikipedia.org] was designed for alien consumption.

Re:Are you guys stupid or something? (2)

Ivoch (1819386) | more than 2 years ago | (#40197267)

2) That doesn't actually matter however since we didn't send a signal at all.

But we did [hellofromearth.net] !

Re:Are you guys stupid or something? (2)

Genda (560240) | about 2 years ago | (#40196381)

The point is if they are in a similar place in their technology as us, we would be receiving their 20 year old signals and there aren't any which is the problem with looking for folks like us. An intelligent life form could speak in a language made of chemistry (the way are cells talk to one another), and we won't hear that. They could be more primitive then us and we won't see that or hear that. They could be tremendously more advanced than us, and using our own advancing technology as a guide, would be producing noise across the EM spectrum, and looking for a signal in any one place might be futile. They may communicate point to point in very short very high energy bursts. They may not want to be seen by primitive species. The list of possibilities is almost endless, and point to real issues about how more advanced species might function in the universe, and there may be species as more advance compared to us as we are to bacteria. A couple tens of millions of years might do that for a sentient species.

So I believe the universe and specifically this galaxy is teaming with life. I just think the factor in the Drake equation that's going to mess with us is the symbol representing the technological state of a society. We have perhaps 20-50 years to go before technological singularity. That means the window of accessibility for a species being easily reachable may be less than 200 years. Making the ability to find others like us exceeding difficult.

Re:Are you guys stupid or something? (1)

Artifakt (700173) | about 2 years ago | (#40196729)

1. Presumably, if post singularity species want to be found, they will, and if they don't, they won't.

2. We can't talk scientifically about such entities, as if they exist, they can pretty much manipulate the scientists into concluding whatever they want. Science studys the natural order - a species whose technology is equivalent to magic will be functionally just as 'supernatural' as though they were genuinely so.

3. If a post singularity alien society doesn't want us to detect them, they may well also not want us to detect other pre-singularity aliens, so in that case, that window for easy detection becomes 0 years wide. Given post singularitans who don't want to openly reveal themselves, the possibiltiy they want to censor pre-singularity civilizations is proportionately higher than that they want to let the little fish communicate unhindered and hide just themselves, and both alternatives are higher than the chance they want to facilitate pre-singularity civilizations meeting even while they hide.

Re:Are you guys stupid or something? (-1)

Anonymous Coward | about 2 years ago | (#40197129)

this galaxy is teaming with life

The word is "teeming" you functionally illiterate fucking idiot.

Re:Are you guys stupid or something? (1)

macraig (621737) | about 2 years ago | (#40196409)

Not stupid at all. There was no broadcast. We were listening with our hands to our ears, not trying to phone them up. We were hoping to hear something from 20 years ago. That's a heartbeat on the scale of sapient civilizations. The likelihood that they'd develop radio sources precisely during the 20 years just before we start listening is pretty slim. More likely is that they heard US first and have 'gone dark' to keep us from hearing them when we'd inevitably get curious.

Re:Are you guys stupid or something? (1)

Paracelcus (151056) | about 2 years ago | (#40196581)

SETI listens, they don't broadcast!

proof? (1)

waddgodd (34934) | about 2 years ago | (#40196325)

The fact that we haven't detected them is proof of their intelligence, no? Would YOU want to be contacted by a race thats major claim to fame (as far as they can see) is "I Love Lucy"?

Re:proof? (1)

Cazekiel (1417893) | about 2 years ago | (#40196367)

It's odd how us cynical humans always conclude that life on other planets are smarter and better than we are. Who knows--maybe they're worse than us. Maybe we're way more advanced than them.

Re:proof? (5, Funny)

gstrickler (920733) | about 2 years ago | (#40196405)

If they're not smarter, better, or more civilized than we are, why would we want to meet them? Dealing with all the idiots here is more than enough, I don't want to have to deal with alien idiots too.

Re:proof? (1)

macraig (621737) | about 2 years ago | (#40196477)

Those idiots you're dealing with might be alien immigrants with really good plastic surgeons.

Re:proof? (0)

Anonymous Coward | about 2 years ago | (#40196627)

And if they ARE smarter, better, and more civilized, they'll find us first.

The Irony (1)

InfiniteZero (587028) | about 2 years ago | (#40196665)

If they ARE smarter, better, or more civilized, what makes you think they want to meet us?

Re:The Irony (0)

Anonymous Coward | about 2 years ago | (#40196721)

Maybe the meat aisle at their version of Safeway is getting low...

Re:The Irony (2)

gstrickler (920733) | about 2 years ago | (#40197065)

That's why we have to look for them. Duh. Think these things through. :)

What makes you think.. (1)

intellitech (1912116) | about 2 years ago | (#40197081)

In the case that they were of equal or higher intelligence, what makes you think they would want to deal with us?

Re:proof? (0)

Anonymous Coward | about 2 years ago | (#40196457)

its odd how people immediately assume that we can contact life forms millions of miles away that don't have the ability to manipulate radio waves in some way.

I mean what, are we supposed to go knock on their door or something?

Re:proof? (1)

Anonymous Coward | about 2 years ago | (#40196551)

Actually, they started blocking all signals in the direction of Earth just over 20 years ago, because they received Star Trek, and do not wish to be seduced and/or two-fist-punched by our Starfleet Captains.

Re:proof? (2, Interesting)

MobileTatsu-NJG (946591) | about 2 years ago | (#40196623)

Yes, they would want to contact us much in the same way we'd be insanely curious if any other creature on this planet demonstrated creative story-telling.

I'm sorry to poop on your post but that Calvin and Hobbes cartoon that inspired your reply is over 20 years old.

Re:proof? (1)

Paracelcus (151056) | about 2 years ago | (#40196691)

If there are space fairing races capable of FTL travel and if they are aware of us, they are terrified that a species of hyper violent savages are about to break free of their ancient battleground and bring the pain to everybody else!

Re:proof? (1)

PlastikMissle (2498382) | about 2 years ago | (#40197099)

Hyper violent compared to what?

We like to paint ourselves as this war like savage race when we don't even have a point of reference. Whatever is out there may very well be as violent as we are, if not more so.

Re:proof? (3, Insightful)

WrongMonkey (1027334) | more than 2 years ago | (#40197361)

Unlikely. The human race is violent to the point of constantly being on the brink of destroying ourselves. Any species that was even the slightest bit more violent than humans would certainly destroy itself before reaching off-planet spaceflight.

Validation? (1)

YodasEvilTwin (2014446) | about 2 years ago | (#40196329)

This result isn't surprising [...] but it does validate VLBI as a very exciting means

I'm a little confused as how a negative result validates the excitement-quotient. Or how this could even be validated in a more meaningul sense -- there's no way of checking the data. Maybe it was a false negative and there's oodles of aliens there.

Re:Validation? (0)

Anonymous Coward | about 2 years ago | (#40196423)

there's no way of checking the data. Maybe it was a false negative and there's oodles of aliens there.

And They would not tell us if the result was positive. They would keep it a secret to avoid panic.

Re:Validation? (2)

mbone (558574) | about 2 years ago | (#40196943)

You have obviously never worked at a VLBI correlator. Trust me, if they found something, you would know.

Re:Validation? (4, Informative)

mbone (558574) | about 2 years ago | (#40196597)

This result isn't surprising [...] but it does validate VLBI as a very exciting means

I'm a little confused as how a negative result validates the excitement-quotient. Or how this could even be validated in a more meaningul sense -- there's no way of checking the data. Maybe it was a false negative and there's oodles of aliens there.

The biggest technical problem in radio SETI is RFI. A signal from the star in question would have a very specific Doppler shift between the VLBI antennas, different from the relative Doppler shifts from any terrestrial RFI, even spill-over from a satellite. You can still have a saturated receiver if the RFI is too strong, but that is less of problem (it's easy to detect), and VLBI really reduces the chance of a false positive to almost nil. You also don't need an actual signal to show that this technique works.

Not disproof, though (1)

macraig (621737) | about 2 years ago | (#40196337)

They might actually still be there and just be maintaining radio silence. We'll hear them eventually... when they show up in orbit around Earth.

Re:Not disproof, though (1)

hemo_jr (1122113) | about 2 years ago | (#40196385)

Also, the higher the data density that any transmission has, the harder it is to distinguish from noise. And encryption will also make a transmission look like noise.

Re:Not disproof, though (1)

macraig (621737) | about 2 years ago | (#40196437)

So that gibberish my wife spouts when she's pissed is really volumes of highly advanced information in disguise? Where do I get a decoder ring for that?

Re:Not disproof, though (1)

tnk1 (899206) | about 2 years ago | (#40196561)

Actually, it is highly advanced information.

The problem the only decoder for that is another female brain. That's why when your wife is pissed at you in hearing range of other women, they start putting their hands on their hips and giving you dirty looks as well.

Re:Not disproof, though (1)

tnk1 (899206) | about 2 years ago | (#40196541)

Thing is, I don't think they're looking for content, but certain characteristics of the signal, such as signal strength and continuity of the signal. One sign a signal may be of intelligent origin is that it broadcasts for an extended period of time. For instance a radio station is on all day long and certainly our outgoing SETI signals were created with the intent to make it as obvious that there was a transmission going on.

Encryption is also a possibility, but a lot of signals we get from space may not be carrying data but they are not at all "noise". Their characteristics can be predicted by what generated them and there is frequently a predictability about the signal that lends itself to an obvious source object. Something that was *truly* random might well generate some notice.

Of course, you're right. There are a lot of reasons to believe that we just can't see their broadcasts. It may well be a very short period of time between invention of radio and the creation of more tight beamed signals that will only be visible if they are directly in the path of the observer. We may well be the only local civilization currently in the period that will broadcast. Even if we assume that there are billions of intelligent species out there, that still doesn't mean any are close to us.

Re:Not disproof, though (1)

mbone (558574) | about 2 years ago | (#40196957)

Ah, but the advantage of VLBI is that, even if they were just putting out noise, it would cross-correlate between antennas and be detected (if strong enough).

Re:Not disproof, though (0)

Anonymous Coward | about 2 years ago | (#40197043)

Although the chances of finding life within the habitble zone of a red dwarf is even lower than other star types. They tend to emit massive amounts of radiation with their violent eruptions. Also due to the lower gravity of the sun, the habitable is relatively close to the red dwarf, so chances of being hit by those x-ray flares are pretty high.

So the signal they're receiving us is what (1)

fustakrakich (1673220) | about 2 years ago | (#40196349)

In Living Color? Absolutely Fabulous? Benny Hill reruns...

What do you expect? (0)

Anonymous Coward | about 2 years ago | (#40196355)

They are on the neutrino internet while we're still trying to get the photon internet working.

Maybe radio waves are out of style... (0)

Anonymous Coward | about 2 years ago | (#40196365)

They're probably using quantum entanglement or something even fancier.

No intelligent life found (0)

Etz Haim (856183) | about 2 years ago | (#40196369)

Proves that the Tea Party has a Gliese 581 branch.

Why should they make any intelligence visible ... (1)

Skapare (16644) | about 2 years ago | (#40196389)

... when there isn't any at all in the direction of us.

Arrogant to presume no life. (2)

axjdo (698085) | about 2 years ago | (#40196427)

Just because there are no detectable radio signals doesn't mean there is no life, it may just be pre-industrial. WWII pushed us into the modern era. Without that we may still be using megabytes or even kilobytes and leaded gas. Maybe there is a planet with a single race and less aggressive tendencies, they may develop in a different fashion, while being advanced they may not be pumping massive RF for long-enough for us to detect. Not every species is going to be or was as addicted to TV and Radio as we are.

Re:Arrogant to presume no life. (0)

Anonymous Coward | about 2 years ago | (#40196453)

Who is presuming no life. It says that they didn't detect it. Nothing more nothing less.

Re:Arrogant to presume no life. (1)

KublaKhan1797 (1240934) | about 2 years ago | (#40196755)

Just because there are no detectable radio signals doesn't mean there is no life, it may just be pre-industrial. WWII pushed us into the modern era. Without that we may still be using megabytes or even kilobytes and leaded gas. Maybe there is a planet with a single race and less aggressive tendencies, they may develop in a different fashion, while being advanced they may not be pumping massive RF for long-enough for us to detect. Not every species is going to be or was as addicted to TV and Radio as we are.

I'm usually pretty quick to throw the 'arrogance' card myself but this isn't arrogance. We simple don't have any better way of detecting life over interstellar distances. Your point is completely valid. There might be life at Gliese 581, there might even be intelligent life but just can't tell. Hopefully some day we will come up with a better way of searching for life but given the distances involved I doubt it'll ever be any kind of direct observation. Look up the Drake equation http://en.wikipedia.org/wiki/Drake_equation [wikipedia.org] for a simplified mathematical approach to estimating the number of detectable civilizations out there. Life could be teeming in the universe but it may be next to impossible to find out for sure.

God (0)

Anonymous Coward | about 2 years ago | (#40196431)

Can You beat up their God, God?

God says...
fled, and escaped.

19:13 And Michal took an image, and laid it in the bed, and put a
pillow of goats' hair for his bolster, and covered it with a cloth.

19:14 And when Saul sent messengers to take David, she said, He is
sick.

19:15 And Saul sent the messengers again to see David, saying, Bring
him up to me in the bed, that I may slay him.

19:16 And when the messengers were come in, behold, there was an image
in the bed, with a pillow of goats' hair for his bolster.

Re:God (1)

Paracelcus (151056) | about 2 years ago | (#40196773)

Can You beat up their God, God?

God says...
fled, and escaped.

19:13 And Michal took an image, and laid it in the bed, and put a
pillow of goats' hair for his bolster, and covered it with a cloth.

19:14 And when Saul sent messengers to take David, she said, He is
sick.

19:15 And Saul sent the messengers again to see David, saying, Bring
him up to me in the bed, that I may slay him.

19:16 And when the messengers were come in, behold, there was an image
in the bed, with a pillow of goats' hair for his bolster.

And the leather of his breeks was old and the feathers of his headdress almost as the swirling snow, his knife and spear point worn and dull. The old mother had taken pity on him as the olden wolf had taken pity on her in her young womanhood.

The ice is falling away from her claws as maggots squirm in her eyes! The spirit of the Mikvah has eaten her soul!

mod 3own (-1)

Anonymous Coward | about 2 years ago | (#40196483)

part of GNAA if Don't feel that

Way back when... (1)

garyoa1 (2067072) | about 2 years ago | (#40196487)

On the other hand, could be radio is prehistoric technology to them. I've been having a lot of problems locating intelligent life on this planet lately.

No radio message != no intelligent life (1)

zill (1690130) | about 2 years ago | (#40196489)

No radio message received does not imply there's no intelligent life there.

Maybe they went into planet-wide radio silence as soon as they received our first transmissions 100 years old, and have spent the last century busy preparing their invasion fleet.

In fact, they probably landed advance scouting parties on Earth to assassinate anyone who have knowledge of their #%!@#70824645[CARRIER LOST]

Means of communication (1)

somethingtoremember (1530149) | about 2 years ago | (#40196495)

What makes the researchers think that aliens would even be using radio signals to communicate? And if they were intelligent, what's not to say that they were simply smart enough not to make as much noise as us humans? What, do you think every intelligent creature thinks of itself as an interplanetary HAM operator or something?

Correction: no signals detected (4, Informative)

Chemisor (97276) | about 2 years ago | (#40196507)

Having no detectable radio emissions does not preclude possibility of a civilization. Our civilization's emissions are already mostly in spread-spectrum format, which is by design indistinguishable from noise unless you know the encryption key. The transmitters we do have usually do not radiate omnidirectionally; that would be wasteful. Antennas are designed to cover the intended audience and minimize leakage outside of it, which makes detecting their radiation unlikely at any appreciable distance.

Futhermore, natural inverse square weakening of the signal makes the signal fade into the background before leaving the solar system anyway. Our TV and radio transmitters are not going to be heard outside the solar system. It is no coincidence that our satellites communicate with highly directional dishes. Directed signals are the only ones that will make it to the next star, so what SETI is really looking for is aliens who are actively broadcasting toward Earth. I don't know why they would be doing such a dumb thing, but who knows, maybe they are a not-too-intelligent life.

Re:Correction: no signals detected (5, Insightful)

thegarbz (1787294) | about 2 years ago | (#40196807)

That's not quite true. Some of our signals are spread spectrum, but the vast majority of licensed bands are still the age old single peak and often at insane output powers. These are very easy to distinguish from background noise, and as often is the case you could simply apply a 25kHz bandwidth and pick one of a few common coding methods and listen right in. The actual use of encryption for radio communication is rare when you're looking at the entire spectrum used over a planet. Hell if you exclude WiFi and satellite TV it's incredibly rare when you look at any major city too.

On that note satellites have pointed dishes because they are incredibly weak. They have to be, it's not like we have power stations up there powering them. When talking to a satellite we're trying to pick out a whisper from an asthmatic across a noisy room. We attempt to make our ears highly directional and filter out other conversations and he in turn cups his mouth to get his little voice that bit higher. That's not what these SETI projects are looking for. They are looking for aliens who have set up multi-Gigawatt transmitters all over their planet, just like we have. The equivalent of a rave happening somewhere else in an otherwise quiet rural town.

Also the directionality equation incorporates both the receive and transmit paths. You could have a perfect unit gain transmitter sending power out equally in every direction and still pick it up line of sight from anywhere you want with a theoretical infinite gain receive antenna pointed in the right direction, providing there's no louder signal source in your frequency of interest in the way. VLBI which is what they are using here provides an incredibly amount of gain at the receive side. Lots of really good signal analysis from multiple dishes result in us using a theoretical dish with a size and gain that could not realistically be constructed.

Some real geniuses came up with these designs and I'm willing to bet they know their antenna theory enough to think that it would be possible to detect a sufficiently advanced civilisation who take a similar evolutionary route that we take.

Re:Correction: no signals detected (1)

XiaoMing (1574363) | about 2 years ago | (#40197249)

Wish I had mod points man.

Dixie Cups (1)

englishknnigits (1568303) | about 2 years ago | (#40196523)

I have three dixie cups pointed at Gliese 581 and they haven't detected any intelligent life either. I guess I have a proof of concept as well? They'd better hope that their expensive radio telescopes can somehow compete with my much lower cost solution that achieved the same lack of results.

Distance a factor? (1)

neokushan (932374) | about 2 years ago | (#40196531)

I wonder if anyone can answer this, though - how far away, is that star system? I ask because we've only been using radio waves ourselves for about what, the past 150 years or so? So that means other planets looking for us would have to be less than 150 light years away* in order for them to detect our broadcasts. Basically what I'm saying is, is that doesn't listening to that star system only prove that intelligent life that used radio waves didn't exist x amount of years ago, with x being how far away the planets are?

On that point, doesn't it make sense to point the telescopes towards areas of the galaxy that formed before ours and if so, is that where this system is located?

* This is my basic understanding of light speed and radio waves - if it's wrong, please let me know and correct me as to why.

Re:Distance a factor? (1)

symbolset (646467) | about 2 years ago | (#40196671)

20 lightyears. So you're in China then? I hear they block Google. That must be horrible.

Re:Distance a factor? (0)

Paracelcus (151056) | about 2 years ago | (#40196815)

Mental masturbation as proof that we are not alone?

Smart people can still have stupid ideas!

Re:Distance a factor? (0)

Lumpy (12016) | about 2 years ago | (#40196887)

It does not matter, even if they were 10 lightyears away they can not detect any of our radio signals...

The 50 Watts from a GPS Sattelite that is 20,000Km away will only have about 2.3e-16% of that signal arriving at the antenna. Radio signals don't go on forever at full power, they drop off really fast.

http://www.antenna-theory.com/basics/friis.php [antenna-theory.com] The Friis Equation is used to calculate this. and if you calculated out a 1Megawatt TV station transmit power to cover even a small 1 lightyear distance... Unless they are intently looking for the signal, and we transmitted at the quietest frequency in the galaxy (Low background noise) ther estill have a very good chance of never seeing our signal.

So at 20 Lightyears, all hope is lost trying to get any TV or FM radio... the only chance is a tightly beamed intentional ultra high power signal in hopes that the target will be listening in 20 years and they have the same technology and frequency range. You have a better chance of getting hit by lightning from a thunderstorm in china while you are in Iowa.

how long will HUMANS be sending radio waves? (1)

Anonymous Coward | about 2 years ago | (#40196539)

We've been doing that for, call it a century. Already it starts to fade: people get audio and video over the internet, generally on point to point wires or fiberoptics. Not hard to imagine that a century from now, we won't be sending much out into space either. It's a waste of power, if nothing else.

So if that's typical, if a civilization has only a few hundred years of spewing crap out into space, the chance our observation overlaps with them doing that is really small, given billions of years of time.

Also, maybe they *never* go through that phase. Maybe they just start out with point to point communication and stay there.

How sensitive are these detectors? (1)

barlevg (2111272) | about 2 years ago | (#40196569)

A large criticism that keeps coming up is that, if they're "more advanced" than us, they might not use radio waves for transmission of data.

But I assume no matter how advanced we as a society get, we'll continue using electricity, and the same could be presumed for other intelligent life. Transmitting power across power lines should generate SOME level of EM-spectrum signal, no? Could we detect that?

Okay, fine. Let's say they no longer use power lines and, say, transmit power wirelessly. Could we detect that?

Re:How sensitive are these detectors? (0)

Lumpy (12016) | about 2 years ago | (#40196775)

Even if we beamed our strongest transmitter at them and used the entire planets power to send a 200 giggawatt signal into a 56db gain dish array at them. The signal that would arrive at their location would be barely above the background noise. and that is using a incredibly tight directional antenna, Hope we get it right for the motion of their star in relation to ours.

Re:How sensitive are these detectors? (1)

khallow (566160) | about 2 years ago | (#40196879)

Even if we beamed our strongest transmitter at them and used the entire planets power to send a 200 giggawatt signal into a 56db gain dish array at them.

What happens if their dish happens to be large and more directional than metal tooth fillings? Then they get signal well above the noise level.

Re:How sensitive are these detectors? (0)

Lumpy (12016) | about 2 years ago | (#40197017)

dude, unless your tooth is 250meters in diameter, I'm already talking that.

And no they DONT get a signal well above the noise level, not at 20Ly out.

http://www.antenna-theory.com/basics/friis.php [antenna-theory.com] - start there to learn about path losses.

A 10,000 Watt signal into a 70DBm antenna and assuming the receiving side has a sensitivity of -124Dbm Like that of the equipment at Arecebo, I'm not assuming super spaceman unobtanium.

The signal at arrival after only 1 light year will be -161Dbm -170 is considered the noise floor on a super clear frequency in the Ghz range.

This is Basic RF stuff here. Do you not know this?

Re:How sensitive are these detectors? (1)

JaredOfEuropa (526365) | about 2 years ago | (#40196865)

Let's turn that around... How much of our own rf emissions would be detected by some faraway listener circling another star? Seems like a long shot...

Re:How sensitive are these detectors? (3, Informative)

mbone (558574) | about 2 years ago | (#40197133)

FTA :

From our results we place an upper limit of 7 MW Hz1 on the power output of any isotropic emitter located in the Gliese 581 system, within this frequency range.

.

That means they could detect a 7 megawatt carrier tone with very narrow bandwidth of 1 HZ (or a 70 MW signal spread over 10 HZ, etc.) BUT, that is isotropic power. If the ETI was using something like the DSN antennas, much less something like Arecibo, they might have a gain of 60 dB, which means we could detect a signal down in the 10 Watt range. This search has enough sensitivity that there are lots of broadcasters on Earth (weather radar and airport radars, for example), that could be detected by this survey, if there happened to be a clone of our civilization at Gliese 581.

Maybe the array is broken? (0)

Anonymous Coward | about 2 years ago | (#40196585)

Perhaps the VLBA doesn't work?

of course! (1)

sribe (304414) | about 2 years ago | (#40196609)

After all, if they let us find them that easily, they wouldn't be very intelligent now would they?

Summary better than the paper (1)

mbone (558574) | about 2 years ago | (#40196695)

the first very long baseline interferometry (VLBI) campaign has been carried out on a SETI target star:

Here is a rare case where a Slashdot summary is better than the original article, which simply claims to be "The First" VLBI SETI, which it isn't, not by a long shot.

This is spectral line VLBI, and I bet almost everyone who has correlated spectral line VLBI has thought "maybe this time..." they will get lucky and see an ETI signal. I know that when Demetrios Matsakis was doing ultra-narrow band spectral line searches for the US Navy in the early 1990's, we used to joke that it was "applied SETI," as it was hard to see how you could get Hz bandwidth spectral lines without an ETI behind it. (And, of course, he didn't find any, or else you would have heard about it then.)

No Intelligent Aliens Detected In Gliese 581 (1)

kstahmer (134975) | about 2 years ago | (#40196707)

Wonder if they’re saying the same thing about us?

What a scoop! (1)

wonkey_monkey (2592601) | about 2 years ago | (#40196715)

no alien signals were detected. This result isn't surprising

Tomorrow on Slashdot: Where Bears Poop.

Honestly... (0)

Anonymous Coward | about 2 years ago | (#40196727)

What makes us intelligent enough to detect intelligent life?

Not Complete... (0)

Lumpy (12016) | about 2 years ago | (#40196751)

" This result isn't surprising, as the likelihood of us stumbling across intelligent aliens living in the Gliese 581 system transmitting radio"

They mean Transmitting on frequencies that WE use. They could have had a different technology evolutionary path, One where they let their Nicola Tesla do a power distribution system like Ours wanted to do here. That kind of system would have made RF of limited use here. So they may have went to Masers or other technology. Maybe even higher frequencies that attenuate faster.

They also may have had a far higher IQ and never created the technology Plague like we have with the Creation of Television.

Just like how the Viking probe looked for life and only found sterile soil and we called Mars dead. When you look for evidence looking down a very narrow tube you will never see anything that is outside of that tube.

no intelligent life (1)

khipu (2511498) | about 2 years ago | (#40196847)

There's no intelligent life there, just "I Love Lucy" reruns and presidential campaign commercials.

News? (0)

Anonymous Coward | about 2 years ago | (#40196939)

Since when is the lack of news considered to be news?

Signals schmignals. They're here. (1)

FuturePerson (2471030) | about 2 years ago | (#40196951)

I have met aliens. From different places. It was not long after I had a conversation with God. I think I've atleast outlined what that what about here before.

Of the aliens I've met, none are probably not from the system on topic here, but I just can't help but recite the following story. While it is a good story, it's not, in my mind, really relevant for the big picture of the fate of the universe and the future of consciousness. I don't know why I would tell this story. I would not rule out mind control. Anyway. Here goes:

Nah. On secondt thought. I'll get back to that. It's a story about one of the groups of aliens I know to be here now. Basically they had a cold war thing going way over there a long long time ago and there was some everybody-killing thing that was supposed to kill only the enemies but went wrong or something or maybe both (or however many) sides had the kill-all-the-others-thing. Whatever it was, killed everybody. Except for some of the crew of a ship in space at the time and the lone tycoon who was flying around space for fun. And the power-elites who knew the end was potentially about to come and then saw it coming and took off, like they would. Anyway. Two ships, designed to last forever, left the planet within, I don't know, a thousand years. And now they're here. But it's all atmosphere or charachter ... something, which is beside the point in the grand scheme of things (i think, now, I might be an idiot/stupid/wrong/blind/mistaken, or something), so I'm not ging to go into anymore detail about all this at this point in time.

~Peace, love and anarchy,
Future Person

Re:Signals schmignals. They're here. (0)

Anonymous Coward | about 2 years ago | (#40197015)

"Aliens are real. The Air Force Don't Exist" - Mad Magazine.

Re:Signals schmignals. They're here. (1)

FuturePerson (2471030) | more than 2 years ago | (#40197305)

Yes and no. Or, should I say, "Yes", "yes it does" and don't. You are spreading the dangerous meme of "what-me-worry", and it is not helping. We, as a planet, are up shit creek, figuratively speaking. We're killing the planet and we're letting stupid ideas guide us and we're letting the psychopaths rule us. The aliens are not important right now.

Sincerelly,
Future Person

Re:Signals schmignals. They're here. (0)

Anonymous Coward | more than 2 years ago | (#40197399)

so, this is the author of the narrator of FuturePerson, pointing out that FuturePerson is a fictional world, not spherical-ish like ours, but a big tower of fictional idiots layered on top of each other all the way down and any judgement or punishment is purely suboptimal.

Likely Conclusion (0)

Anonymous Coward | about 2 years ago | (#40196989)

It is a 50/50. It is likely to assume that highly developed intelligence would, at some point, harness the radio wave. They may, as we do now, and leave it behind for something better, but at some point they are likely to have used used it. If so, it is a detectable event. On the other hand they may not have used it yet, and if so they may be inferior or stronger, they may be on the brink of discovering radio waves or they may already have deemed it inferior to something better.
We may look, but what to look for?

We can't detect the signal at the distance (1)

jonfr (888673) | about 2 years ago | (#40197047)

The problem is not that we can't detect the signal. We got all the hardware. The problem is that we might be well outside the radio signal range to be detected, as radio signal can only be carried so far by its power. But the best option for accurate detection would be to place a radio monitoring hardware just outside the orbit of Pluto for that purpose.

http://www.computing.edu.au/~bvk/astronomy/HET608/essay/ [computing.edu.au]

perhaps they read the killing star? (0)

Anonymous Coward | about 2 years ago | (#40197203)

and know its not a good idea to make lots of noise in case whoever is listening decides to kill them with relativistic weapons of mass destruction?

we shouldn't be here (0)

Anonymous Coward | more than 2 years ago | (#40197357)

The human race should not be here - its only with extreme circumstances we are; here is no life out there because there should not be.

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