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Space Communications

Latest Search For Alien Civilizations Looked At 60 Million Stars, Detects No Signals (iflscience.com) 154

schwit1 writes: Are there aliens out there? Breakthrough Listen, a privately-funded project searching for evidence of alien life, has released the first results from its survey of 60 million stars in an area looking towards the galactic center, noting that it found no evidence of any technological transmissions signaling an alien civilization from any of those stars. The kind of signals they were looking for were not beacons sent out intentionally by alien civilizations, such as television or radio broadcasts, but unintentional transmissions, such as radar transmissions meant for other purposes but still beamed into space. They found none. The paper can be downloaded here (PDF).
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Latest Search For Alien Civilizations Looked At 60 Million Stars, Detects No Signals

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  • In other news: UFO Picture Does Not Exceed 8 Pixel Accuracy
  • by Agent Fletcher ( 624427 ) on Friday May 07, 2021 @02:16AM (#61357640)
    SearchIng 60,000,000 stars with an estimated 1,000,000,000,000,000,000,000 stars in space that we know of means we searched about 0.00000000000006% of known stars for life. Yeah basically zero.
    • The odds of winning a recent Powerball drawing in Tennessee was 1 in 292.2 million

      We're more certain of the impossibility of winning the Powerball jackpot than we are of intelligent life in the galaxy.

    • by jcochran ( 309950 ) on Friday May 07, 2021 @02:54AM (#61357714)

      Quite a few zeros you've placed there for no reason. The researchers aimed their search at our galactic center. The Milky Way has somewhere between 100 to 400 billion stars. The reason they aimed at the GC was because there is the highest density of stars to observe. But Howard Tayler of Schlock Mercenary https://www.schlockmercenary.c... [schlockmercenary.com] has a nicely pithy thing to say about stars near the GC.

      "The evolutionary program of organic life doesn't iterate effectively when the sky mashes the reset button every five to ten thousand years."

      The authors do take into consideration some of the issues with instability near the GC, but there's quite a bit of handwaving involved.

    • by MightyMartian ( 840721 ) on Friday May 07, 2021 @08:18AM (#61358370) Journal

      It's worse than that. Considering that any signal of normal power would lose coherency over a few dozen to maybe a few hundred light years, unless an alien civilization is pointing a highly directional and very powerful signal right at us, we're not likely to ever see it. As a technique for catching bits of some nearby civilization's version of "I Love Lucy", these projects are an utter waste of time, since such signals will be of relatively low power, will dissipate over any significant distance, if not outright swamped by other sources of radiation.

      I suspect when we seriously starting looking for life (intelligent or otherwise) in other stellar systems, it will be through future generations of telescopes which will be able to image alien worlds sufficiently to detect continents, oceans, and makeup of atmospheres. Looking for radio signals is a fool's errand.

      • by cusco ( 717999 ) <brian@bixby.gmail@com> on Friday May 07, 2021 @08:40AM (#61358440)

        They're not looking for 'I Love Lucy', they're looking for the DEW Line. The much-lamented Arecibo telescope dish would have been able to detect its twin sending from the Andromeda Galaxy. That they haven't found it yet is not surprising, if other technological civilizations follow our trajectory (a dubious assumption, but we only have a sample size of one). A hundred and fifty years ago we would have been undetectable by radio signals. As we move away from powerful broadcasts to weak directed signals it looks like in another fifty years we will probably again be undetectable. That's less than two percent of the length of our civilization so far, and we barely have space flight.

    • They did not search for life.
      They searched for transmissions.

      Even if all those stars (erm a planet around those stars) would send out transmission:
      * how likely is it that one can be detected from our position?
      * how old would be the transmission?
      * how can you even be sure it is from that star/plant which was a few thousand years ago at a different position?
      * why would they - and how would they - aim a transmission at us, as we also were a few thousand years ago at an totally d

      • Well, not so "totally different position in the galaxy" as all that. We've moved maybe 25 light years in the last 30000 years.

        Of course, we haven't been capable of doing anything detectable for much longer than a century, so it'll be 60K years (39K years before they detect us, another 30K years before they can signal get a signal back to us) before someone down near the core of the Milky Way could possibly respond to us.

    • Assuming that there are at least 10^20 stars, that means we look at 1 in 10^12 stars. That is like looking at a 10 centimeter square piece of the earth and saying there is no life.

      As always, a random positive result would have been interesting, but a negative results shows nothing.

      • by EnigmaticSource ( 649695 ) on Friday May 07, 2021 @10:56AM (#61359022)

        If you can't find life in any random 10cm^3 bit of the surface of the earth, you really aren't looking that hard. Life is stupidly pervasive on earth, and if you're looking at unicellular things and spores you'd probably have a hard time finding a cubic decemeter of air devoid of life.

        However, you're completely right about the absence of evidence is not evidence of absence... Your metaphors could use a bit of work though ;)

        • I invite you to go look for life in a ten cubic centimeter patch of hot magma. Go on, you could make the breakthrough of the year xD

          It would be very exciting to find microbial life on Mars, for instance, but somehow I doubt it'd return our calls if we tried sending radio broadcasts at it.
          • You're totally right, and random is just that; it is possible to find a null patch of earth, but they are excruciatingly rare, and you wouldn't want to be there anyway. They're so exceedingly rare, it's effectively certain that unless you set out to find nothing, you'd find something living in your sample; it's the scientific version of being willfully obtuse about edge cases.

            I dunno, maybe that's the right way to think about it though, since despite our best efforts and models, we seem to be an inexplicab

            • by fermion ( 181285 )
              To make the analogy work, we are looking for intelligent life, radio signals, not just bacteria. I think there is a much greater than 50% chance there is no sign of intelligent life on a random 10 cm square of earth.
              • You know, the reason why they call it then Anthropocene is because there isn't anything left on this rock we haven't marked with signs of intelligent life.

  • by Maelwryth ( 982896 ) on Friday May 07, 2021 @02:28AM (#61357666) Homepage Journal

    In the last two hundred years we have gone from radio to the Internet. In another two hundred who knows what we will be using. Sure, we have to look. You don't generally get to find things if you don't but it's a little hopeful to imagine that not only is there intelligent life but that it is at the same level as us.

    I imagine that when we do find evidence of another civilization they will be either way ahead of us or way behind. Probably the former. And we will say, "Of course, how could we have missed it!"

    • by DamnOregonian ( 963763 ) on Friday May 07, 2021 @02:51AM (#61357708)
      They don't even need to be way ahead for us to miss them.
      Further more, there's no saying "way ahead" is actually any harder to see than we are now.
      The truth of the matter is that our ability to observe such signals is very, very poor.

      This study was looking for signals with a minimum EIRP of 10^14W/Hz.
      This means they're looking for things stronger than Arecibo blasting its radar full power. Directly at us.
      Since we ourselves weren't even ever sweeping the skies with Arecibo firing at full blast, it seems bizarre to be surprised by aliens not also doing that.
      • And even if we were doing so, an alien civilisation looking for us located further than 120 ly away wouldn't detect us either.

        • by cusco ( 717999 )

          And if their version of Arecibo was pointed in a different direction at the time we were monitoring their system we would still have missed it.

          • Precisely.
            And if they've got a spherical reflector visible from orbit pointed directly at us, transmitting with enough power for us to catch it with ours, for long enough for us to tell what's coming out of it, I'm really not sure if I feel good about that.
            • by cusco ( 717999 )

              Well, since they would have had to send that signal two and a half million years ago I wouldn't worry overly. We had barely come down out of the trees by that time.

      • Wish I had mod points. The broadcast power question is what I was wondering about as well. There are lots of questionable pieces to this, including only looking at the galactic center, how much radio power can they really see, and how small of a fraction of the sky/stars this really was.

        OTOH, this seems like a swing-for-the-stands approach. If they HAD found something, they could have said "even in an inhospitable environment, only a small fraction of stars is teeming with civilizations that are absolutely

        • Broadcast power is one thing, but consider that the rest of the universe doesn't have to follow our evolution, and the signals we use today. It's almost narcissistic to believe that others would follow the same path we have, and therefore, we listen to signals from ourselves, rather than a broader context-- if within the constraints of physics.

          We flatter ourselves that we might see modulations and signal propagation behaviors of Faraday, Maxwell, etc. These are not the only ones, just the ones of inventors

          • While I certainly understand the point you're trying to make, I think you're invested too much in the idea of "the possibilities of science are limitless"

            How many entirely separated human civilizations developed bows, clubs, and swords?
            Sure, they're all human, you may say. But those things weren't built into our DNA.
            It's also quite possible (and I'd argue likely) that science evolves, in general, along the progressive path we have taken, more or less.

            We flatter ourselves that we might see modulations and signal propagation behaviors of Faraday, Maxwell, etc.

            This is a great example.
            Maxwell's equations modeled

            • I certainly don't believe aliens can defy physics, although humans do on a daily, even hourly basis, demonstrated by the morning traffic reports on the radio.

              Transmitters in the 1920s used hundreds of thousands of watts because little was known of the layers of the ionosphere, the effects of sunspots on radio propagation, and we need only look at how WiFi evolved from data rates of a signal flagger to something that we call gigabits/sec.

              As discoveries march on, we learn more and more. I maintain that it's h

              • I certainly don't believe aliens can defy physics, although humans do on a daily, even hourly basis, demonstrated by the morning traffic reports on the radio.

                Wut?

                Transmitters in the 1920s used hundreds of thousands of watts because little was known of the layers of the ionosphere, the effects of sunspots on radio propagation, and we need only look at how WiFi evolved from data rates of a signal flagger to something that we call gigabits/sec.

                Even more wut?

                As discoveries march on, we learn more and more. I maintain that it's hubris to believe that our way, our evolution, is the only way, and that radio is the sniff-test for alien civilization. Just because we can think and outwit and dominate THIS planet means nothing. Although we're at the top of our food chain, there may be an entirely, not understandable or completely different civilizations based on values beyond the limits of human comprehension.

                Ok, this just diverted into a discussion of aliens that have different values than us.
                I have no problem with that.
                That's not what we're discussing though.

                Crap, we can't even get people to get vaccines in a pandemic, and credulity for science battles with power and greed. What makes us think we're even looking for the right waveforms, the interesting modulations, or that another civilization even cares if we here it, twenty thousand years later?

                Absolutely nothing.
                We're looking for any modulation.
                Unless they're using some kind of secret squirrel noise emulating modulation, we're going to see the modulation carrier because... well, as you may have guessed, it looks quite different from noise. We need not understand the modulation.

                Again, I appreciate the point you're trying t

                • I'm not insulting the intelligence of every human alive, rather, just because we're at the top of one food chain doesn't mean we're either overly-intelligent, or at the top of far more sophisticated food chains that we could not have imagined.

                  I cite the near-megawatt transmitter of yore because we can do the same thing with a microwatt today. The data density/sec of WiFi fifteen years ago was laughable by today's standards, and we've not pushed the boundaries of physics.

                  These are examples, but also examples

                • +1 Insightful, with high SNR

              • I maintain that it's hubris to believe that our way, our evolution, is the only way, and that radio is the sniff-test for alien civilization.

                So you're proposing we do magic to find them?

                Care to explain what else we could possibly observe from hundreds of light years (and much further!) away?

                Are we listening for audible noise from them? Smelling for them?

                The reason we're listening for radio signals is because that's the only observational tool we have. On top of that, it's the only thing that we know of that can be made on a sub-planetary scale which could reach out into the cosmos. Yes, maybe some day we'll discover quantum faster than light sub

            • Perhaps you imagine aliens with big steam punk victorian power supplies driving crude lasers on space ships with spikes on them or something?
              You forgot that those ships are crewed by vampires and weres!

          • Comment removed based on user account deletion
      • True. And with the times involved they could be on our metaphorical doorstep by the time we spotted anything weird. Its 27,000 or so light years to the galactic core...
    • The problem is that we really don't know what the chances are. Maybe in few hundred years we figure out that the great filter for all the ones to come after is the first civilization to get up and running and we are it. I mean chimps will never get to build their own civilization unless its in a zoo managed by us and Neanderthals sure aren't around to ask "Where are the others?". Why would you think this must be all that different on cosmic scale?
      • by Zocalo ( 252965 )
        I think it's entirely possible that we're in the process figuring out what the great filter is for ourselves right now. It seems pretty logical that any aspirant space-faring civilization is going to need fuel for an industrial revolution of some kind, and that almost certainly means consumption of natural resources on a large scale - most probably via combustion, although you can't safely assume a suitably oxygen-rich environment is synonomous with civilization, let alone sentient life. If you can't figu
        • Also people often forget a very important thing, time scales. It took all of human history up to this point for us to develop enough technologies and knowledge to be able to "listen" in on the universe. These 200 thousand years, or even millions, are still a mere fraction of the universe's time lapse.
          There could have been millions of space-faring civilizations before, and there will maybe be millions more after that, but all of them would come and go at different times and just miss each other by mere secon

        • by DarkOx ( 621550 )

          The filter does not even need to press the reset. It might be that interstellar travel is more or less simply beyond our reach.

          As it stands today physics says chemical energy just won't take us many of the places we want to go. Atomic energy might but only if we are willing to go slow. The energy required to go anyway fast in terms of human life times juxtaposed against stellar distances rapidly moves beyond anything we have the ability to generate or manage if we could.

          Even going Alfa Centuri is probably a

      • Most Apes are in the stone age. If mankind would disappear one or more of them would likely evolve and take our place. There is no scientific reason why they would not.

        • No scientific reason other than the fact that intelligent life has only arisen once in 4 billion years on earth. I mean, dinosaurs might evolve again too, but I wouldn't bet on it.

    • I imagine that when we do find evidence of another civilization they will be either way ahead of us or way behind. Probably the former. And we will say, "Of course, how could we have missed it!"

      Today, we still speak in terms of light years when it comes to searching for other life forms. And yet, we still don't hold technology that comes anywhere close to getting us anywhere near that.

      To put that into perspective, it takes us humans months to travel less than three light minutes between here and Mars.) It's taken half a human lifetime for Voyager 1 to travel a whopping twenty one light hours. THAT is how far we humans have sent anything from this planet.

      We could discover 1,000 life forms that a

    • by glatiak ( 617813 )

      Not just that, but the period where high power transmitters were the norm was quite brief. Around here in eastern Ontario the TV stations on both sides of the border moved from to digital broadcasts and dropped their transmission power. The radio I listen to comes from directed satellite beams and internet connectivity comes from optical fibre or short range cell broadcasts. Anyone observing our broadcasts would need to catch that brief window when it was all being blasted in all directions.

      Space is really

    • Exactly this point is important to remember. We dont know what to look for. We have no clue what kind of signal we should expect. This time they looked for very large radar bursts.

      And not only that. Even if we could assume that someone was at the "radar" level of technology, how long would they be that ? Would they still keep firing their radar at us ? And if they did so for... Say 1000 years, and the signal travels at the speed of light, would the civilization still be there when the signal arrived ? Would

  • Then they're hiding. Kinda the way we'd stay away from a water source known to harbor huge colonies of deadly bacteria.

    • Poking one's head out of the sand and saying hello could be an extinction-level mistake. Hopefully nothing evil noticed Earth in the brief window where we were really visible and decided to go sterilize the system "just to be sure."
  • Maybe (Score:4, Insightful)

    by MrKaos ( 858439 ) on Friday May 07, 2021 @03:02AM (#61357728) Journal

    Smart civilizations hide their presence from aggressive species. Maybe only dumb naive species make their presence known.

    • By firing a nuclear reactors at random, like the voyager space probes. Gee, I wonder how that will look to any developed aliens. Maybe it wasn't such a good idea to add an image showing what we look like.
      • by skam240 ( 789197 )

        You mean power sources that any species we'd ever have to worry about would recognize as such?

    • Smart civilizations hide their presence from aggressive species. Maybe only dumb naive species make their presence known.

      What makes you think that other civilisations are any smarter than our own?

      • by mridoni ( 228377 )

        What makes you think that other civilisations are any smarter than our own?

        Right, but you have to admit we set the bar quite low...

        • Re:Maybe (Score:4, Insightful)

          by thegarbz ( 1787294 ) on Friday May 07, 2021 @05:42AM (#61358012)

          Compared to what.

          I do get what you're saying. Humans are the worst. But I actually believe that any civilisation of a reasonable size that remains free thinking will fall into the same pattern. Humans are not a singular entity, not a mind hive. We've developed across the world in a tribal way, each isolated and one thing we have proven: All free thinking tribes formed religion, all free thinking tribes started fighting, and all people in the entire world in some way look out for number one to the detriment of all others and possibly the complete destruction of our own environment.

          Humans suck, but we may be the best the universe has to offer. Now with that sobering thought it's time to open a beer.

          • by sinij ( 911942 )
            If we are alone, which I highly doubt due to probabilities, the worst and the best qualifiers in a set of sentient species: {humanity} are meaningless.
    • Smart civilizations hide their presence from aggressive species. Maybe only dumb naive species make their presence known.

      Which is stronger:

      A) An alien life forms sense of smell to be able to sniff out aggression from light years away.

      B) Their ability to ass-u-me.

      C) Yours.

    • You must have read Dark Forest. Very cool how it solves the Fermi paradox.

  • by AntisocialNetworker ( 5443888 ) on Friday May 07, 2021 @03:36AM (#61357778)

    It's inevitable that an alien life-form will eventually evolve an Elon Musk. A century later, they disappear behind a wall of space debris.

  • by Narcocide ( 102829 ) on Friday May 07, 2021 @03:46AM (#61357798) Homepage

    Have you seen what we are wearing?

  • ..We only started broadcasting ~80 years ago, now most of our communications are changing to point to point, compressed and encrypted

    If we looked for similar from other civilizations we would expect to miss most of it, and the odd signal we happened to intercept would look like white noise

    • That's a fair point. I'm curious how Earth's total human-made radio power has changed over the decades. We're probably not broadcasting radio or TV the way we used to, but we have a lot of cellular and wifi communications.

      I guess in general it's logical that we continue to use radio for data transfer for awhile - we've built a large infrastructure around it. But if we start trying to power things wirelessly, our planetary RF power could increase many fold.

      • This thread is missing an essential component of the noise, that of where it lies in electromagnetic spectrum. White noise would imply it’s hard to distinguish from the background noise, but there are frequencies you see much less power from and many of the common molecule absorbion bands have very little noise. So even if you only pick up white noise, one could be as close to100% sure as possible it’s artificial in origin.
  • We weren't expecting life to survive there and we weren't expecting to be able to hear leakage at any significant distance. They confirmed these expectations with variable confusion at significant cost, but somebody got paid, so OK.

  • It's rather searching for another Human civilization. Because an Alien civilization, as much as they may be "smart", might not use the same vectors of communication as us.
  • So if we are using radio to find it we have to catch them at the right age in time also. And i think thats fairly short time. Now we use radio alot here on earth. But in a few hundred years or so i think we will be using quantum communications more or some other type and they dont send out signals we can detect. So not only is there a massive amount of stars to sift trough we also need to find them in a window of a few hundred or couple of thousand years in their evolution. And that brings down the likely hood even more of finding them. And honestly the likely hood of finding someone else in similar evolution stage as us is even smaller. After all how would a caveman beating on a hollow tree trunk communicate or even detect the signal of someone screaming in to a ham radio.
    • I honestly dont think we will find anyone untill we stumble across them face to face out there. So stop wasting money on detecting them here and put it on efforts to go out there looking instead.
      • >I honestly dont think we will find anyone untill we stumble across them face to face out there. So stop wasting money on detecting them here and put it on efforts to go out there looking instead.

        I think you haven't considered how incredibly difficult it is to travel across interstellar space.

        Now, I also think the people looking for radio emissions are unreasonably optimistic given the inverse square law, and our own experience with simply not wasting energy bleeding signals into space once we figured ou

  • by Martin S. ( 98249 ) on Friday May 07, 2021 @08:21AM (#61358378) Journal

    An absence of evidence is not evidence of absence. This is the expected result, the chances of finding anything given the numbers and L from the Drake equation [wikipedia.org], the actually remarkable result would be finding some evidence.

    • by ledow ( 319597 )

      The remarkable result would be finding anything that was indistinguishable from noise.

      The period for which a civilisation is putting out large, powerful, unencrypted communication that leaks to the galaxy is extremely, extremely tiny.

      And encrypted secure comms are patternless and indistinguishable from noise, and modern civilisations would be doing it with the minimum amount of power unless they wanted to send out a beacon (which is generally agreed to be a bad idea for any sufficiently advanced civilisatio

  • I, for one, welcome our new undetectable stealth overlords.

  • I’m willing to throw down on the first signal being received, and finally decoded, reveals a rather cute if not bizarre creature playfully meandering around its environment. Well, that or *shudder* alien porn.
  • The way they vote they seem to be from another planet and they say the coastal state voters seem to be from another planet.

    One of them must be right and so there must be aliens somewhere around here.

  • Failure to see a signal is to be expected. They don't want us to detect them until we are ready to handle an alien civilization. For starters, they were waiting to see if Facebook would reinstate Trump.

  • Well what did we expect? Pretty sure aliens have been aware of us ever since episodes of "I Love Lucy" started reaching them and then they must have immediately banned any sort of communication in this direction.

  • Unlikely to hear anything because lets consider if little grey men are operating a Alien 103.5 FM station at 100,000 watts on their home world. The signal strength fades into the background very quickly, its hard to pickup if you are 100 miles away, impossible at the distance of another solar system. The signal most liley to travel interstellar distance is a tight beam like signal such as a microwave dish operating at high power, and then you have to be in the path of the beam to receive it. When you here o

    • by PPH ( 736903 )

      Alien 103.5 FM station at 100,000 watts

      And that might only exist for a hundred years or so. Consider how we are moving away from large, single transmitters to grids of low power cellular sites over which we can stream video and audio.

  • Think of it like this: since the start of the universe, we started emitting radio signals and visibly changing our planet in the last 100 or so years. If we assume that we're not exceptional and a somewhat average civilization, most others (if they exists) are at a similar level of development (there could be outliers).

    So, unless they're really close to us, the chances we'll detect anything are close to zero, unless we luck out and find an outlier.

  • First, our radio signals have been dropping, as we do to cable, fibre, and directed links.

    Second... they're really going to be using radio and radar a thousand years from now?

    Third: they're looking towards galactic center... where the radiation level gets higher, and unless there are life forms that use radiation, is far less friendly, and it gets worse as you look towards the Milky Way's black hole.(Sagittarius A).

  • Remembrance of Earth's Past is an excellent 3-book series (The Three-Body Problem is book one), and the end of Book Two is an excellent warning of the consequences of loudly declaring our location. It may be that we don't detect any transmissions because either a) the ones that used to transmit are destroyed, or b) smart civilizations are keeping their existence low-key.

    I see great benefit in space travel and exploration, and becoming a multi-planet species. As a kid, meeting alien life seemed extremely co

  • So what does it mean? Well nothing. How far are these stars? How long would an alien signal need to travel to get to us? How strong is the signal that they send? What signal are we looking for? Do we even recognize a signal? There is probably 100 million alien races in the universe, probably more if you think about it. How big is the universe? How old is it? How many stars? How many galaxies? How many clusters? We know shit...

The truth of a proposition has nothing to do with its credibility. And vice versa.

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