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Alien Contact Unlikely For Another 1,500 Years, Says Study ( 159

An anonymous reader writes: Astronomers at Cornell University predict based off estimates that alien contact is unlikely for another 1,500 years. MSN reports: "According to the astronomers, signals from Earth would need to reach half of all the solar systems in the Milky Way in order to be picked up by an intelligent life form. Given that signals from TV and radio were first sent into space as a byproduct of broadcasting 80 years ago, it will take around 1,500 more years for aliens to receive, decode and respond to the signals." A co-author of the paper who will present it at the American Astronomical Society's meeting on June 16, Evan Solomonides, said, "We haven't heard from aliens yet, as space is a big place -- but that doesn't mean no one is out there. It's possible to hear any time at all, but it becomes likely we will have heard around 1,500 years from now. Until then, it is possible that we appear to be alone -- even if we are not. But if we stop listening or looking, we may miss the signals. So we should keep looking." Stephen Hawking and Russian entrepreneur Yuri Milner announced a $100 million research program in April to send robotic probes the size of postage stamps to nearby stars within a generation.
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Alien Contact Unlikely For Another 1,500 Years, Says Study

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  • What? (Score:2, Insightful)

    by Anonymous Coward

    I've already made contact

  • by turkeydance ( 1266624 ) on Wednesday June 15, 2016 @04:58PM (#52324875)
    we want to get paid
  • by Geoffrey.landis ( 926948 ) on Wednesday June 15, 2016 @04:59PM (#52324885) Homepage

    The Solar System is 25,000 light years from the center of the galaxy. So, it takes 25,000 years for signals from Earth to reach half of the solar systems in the galaxy... and another 25,000 years for them to respond.

    • by Zak3056 ( 69287 ) on Wednesday June 15, 2016 @05:07PM (#52324945) Journal

      In 25,000 years, you'd reach far less than half. I don't feel like trying to do the math, but suffice to say that a circle centered on Sol with a 25,000 LY radius contains more like 25% of the stars in the milky way (if that).

      • In 25,000 years, you'd reach far less than half.

        Exactly and tracing the article back to the original Cornell press release [] it is not a mistake in the reporting either. I expect there will be a few red faces in the media relations department at Cornell soon...

        • There are considerably fewer than 1 percent of the solar systems of the Milky Way within the distance implied by a response arriving to Earth within 1,500 years.

          If those aliens were to respond as soon as they detected our signals, and if we were to detect their response exactly 1,500 years from now, then those aliens would be 790 light-years away. Our signals have already traveled 80 years outwards. In 710 more years they would reach those aliens. The return trip would take another 790 years making a total

    • If they see what is on television here . .. . I doubt if aliens would respond to us . . . CSI: Mars, indeed . . .

    • by rtb61 ( 674572 )

      Even at that speeds the galaxy has been around for billions of years and even those closest to us in evolutionary terms, cropping up every at logical minimum hundred thousands year to a logical maximum 10 million years, means they have had a shit bucket ton of time to place satellites around every likely planet so they can watch the next species tear itself apart as it tries to evolve from it's planetary cocoon to become a galactic species.

      So what this statement really says is, "I can not imagine any way

      • Yes.
        If an advanced civilization is or was out there, probes will have been placed in a nice and quiet place like Pluto or Mars, and the time it takes them to know about us is the time for their fastest way of communication back home.
        If they decide to come visit is another question, maybe when we have something interesting to offer them.
        If they are not more advanced than us, what is the point in them finding out we exist? Communication?
        An extraterrestrial pen pal would be cool, but the 1500 year reply ti
    • ...unless they have FTL capability.
  • by Haxzaw ( 1502841 ) on Wednesday June 15, 2016 @05:01PM (#52324899)
    I'm pretty sure the aliens are coming back next week... on June 24th at a theater near you. "Independence Day: Resurgence"
  • *Study funded by Aliens Anonymous

  • by Anonymous Coward

    If you have listening devices at some grid spacing, then you can, with some wiggle room, fire up some kind of kill vehicle for the star that is emitting them. Spend a couple centuries accelerating as close to light speed as you can, make a nice gamma ray burst. Keep the skies quiet.

    Weak aliens wouldn't detect anyone, or make any sign.
    Powerful friendly aliens would have made a big sign trying to sell you alien Jesus, and tell you how to build something helpful.
    Powerful hostile aliens would either try to te

  • Radio interference (Score:4, Interesting)

    by scorp1us ( 235526 ) on Wednesday June 15, 2016 @05:13PM (#52324977) Journal

    How long until those signals are indistinguishable from background? It's not just that the signal is there, but that the SNR is low enough to stand out.

    • About a light year, I believe -- so nobody is going to be picking up our TV signals. We could send a detectable signal to nearby stars if we wanted to, but we aren't.

    • by aepervius ( 535155 ) on Wednesday June 15, 2016 @05:59PM (#52325233)

      More or less since the first signal we blasted out for tv and radio where omni-directional , count about 1/r^2 decay in intensity. A few hundred AU at most a few light year (e.g. we are almost not detectable if we had a SETI outpost placed on our nearest neighbors). Basically what our SETI is trying to detect , is intentional unidirectional powerful "we are here" signal sent by an ET civ, like we did in direction of Gliese or M13. There is a nice table with all signals including TV and maximum range : [] scroll to "Table 1 Detection ranges" for assumption and detection range. Basically the only signals ET could detect beyond 10 LY, is our own intentional signals sent from various folk in the last 4 decades, and those maximum are around a few hours duration top.

      • by Anonymous Coward

        If we ever invent FTL I wonder if we could travel way out, build a big dish, and retrieve the lost TV episodes of early Dr. Who? Some lost movies?

      • by delt0r ( 999393 )
        If if its not omni directional you still get 1/r^2 decay in intensity. Even with lasers. The beam is still spreading out even with diffraction limited "optics".
    • For a 1 MW omnidirectional broadcast TV signal, the receiving antenna would have to be have to be a perfectly aligned directional antenna at least 2e-10 radians across. That's 300 miles at 1 light-year. (Warning, that's very sloppily approximated.)

      Conclusion: Nothing is going to see broadcast video from Earth beyond a small fraction of a light year. For signal intercept to happen at hundreds of light years, both sending and receiving antennas have to be very narrow beam and aimed at each other.

    • Even if you're in geostationary orbit, the SNR ratio for most of our TV shows is pretty close to zero. At least with the right definition of "noise."
  • So using only early 20th century technology and understanding of physics for.. forever and assuming alien life is also operating under this handicap, it is likely to take 1500 years to contact alien life. Good to know.
    • Oh look. Someone who thinks physics is going to radically change and we are going to be flying through wormholes in the future.
  • There is not much possibility of our signals being heard due to the inverse-square law. []

    Most of our signals will be indistinguishable from the CMB, and if we generate a massive focused beam, we are going to have to be so precise, that it is most likely not feasible. 2 completely unrelated points traveling in 3 dimensional space, and we would somehow have to send and receive a beam (because sending one way is useless) when there is no way to guarantee where the other point will be due to all the exotic forces

    • by Kjella ( 173770 )

      and we would somehow have to send and receive a beam (because sending one way is useless) when there is no way to guarantee where the other point will be due to all the exotic forces in the universe. Sounds like magic.

      While we don't exactly understand why the stars seem to be affected by a gravitational pull from dark matter, doesn't mean we can't measure the relative motion with a very high degree of accuracy []. It is highly likely that our ability to predict the source of a transmission and the place we'd need to aim to reply - down to arc-milliseconds - far exceeds our ability to focus a beam so narrowly.

  • Is astronomical
    • The guess work here ... Is astronomical

      You might be going for a joke here but I think you're spot on. Humanity has only been space-faring for a few decades and is already (almost?) able to detect oxygen in the atmosphere of another sun's planet. Nothing screams LIFE like detecting earth-like levels of free oxygen. If we detect oxygen, those systems will go to the top of the list for visiting when (not if) we get interstellar capability.

      With 21% oxygen in the atmosphere [], the earth has been screaming LIFE

  • A research paper I read in the last few years showed it's very unlikely for TV and radio signals to propagate far beyond Alpha Centauri without deteriorating to the point of being completely unintelligible. Fox News, doubly so.

  • by mveloso ( 325617 ) on Wednesday June 15, 2016 @05:21PM (#52325027)

    1500 years to get there, 1500 years for the reply?

  • by ortholattice ( 175065 ) on Wednesday June 15, 2016 @05:38PM (#52325119)
    The assumption is that we have to initiate contact for them to respond. Why wouldn't they be trying to initiate contact also? In theory, we could hear from them tomorrow if they are more advanced and initiated contact long ago.
    • by Creepy ( 93888 )

      The assumption also is that they didn't do this, say 2 1/2 million years ago and gave up 5 years later. A lot of factors led to intelligent life on earth and expecting it all to happen at the exact same time somewhere else is ridiculous. I expect when we do find life on other planets, we'll find a lot more dumb life before we find intelligent life.

  • Such Nonsense (Score:4, Insightful)

    by argStyopa ( 232550 ) on Wednesday June 15, 2016 @05:46PM (#52325175) Journal

    "predict from estimates" Really?

    Seriously, does anyone even 'journalist' anymore?

    This is a simple wild-ass guess based on NOTHING. Aside from that simple fact...

    They "guess" that signals would have to reach "half the systems in the Milky Way" to have a reasonable chance of being intercepted...but then say that this will happen in only another 1500 years.

    Quick hint: just looking at it as a 2d issue, the Milky Way is 100,000 ly across, more or less. It doesn't take a mathematician to realize that a 1500-ly radius circle doesn't come CLOSE to hitting 'half the systems in the Milky Way'.

    For those mathematically bent, a 50k ly radius circle has an area of about 8x10^9 sq ly.
    A 1500 ly radius circle is 7x10^ about 1/1000 of the galaxy, not half.

    "Experts", eh?

    • Every time I see another one of these "Scientists predict x% chance of alien life somewhere, somehow" I get more and more annoyed, because the whole thing is about as scientific as predicting the number of angels currently dancing on pinheads, yet this crap somehow keeps getting published.

      We have abolsutely no idea of the likelihood of life on other planets, or of the probability that that life will evolve into something that will be "intelligent" in a way that can comprehend or respond to our signals.


  • At the rate things are going, the human race may not exist in any significant way 1500 years from now. We'll either pull ourselves out of the various tailspin-inducing shenanigans, or it'll get us.
    • At the rate things are going, the human race may not exist in any significant way 1500 years from now. We'll either pull ourselves out of the various tailspin-inducing shenanigans, or it'll get us.

      Not to mention the Vogons who are lobbying to build an hyperspace bypass.

  • "Earth would need to reach half of all the solar systems in the Milky Way" I think all the people is science should know there is ONLY one Solar System in the Milky Way. There is a lot of other star systems in the Milky Way. Tim S.
    • by tsqr ( 808554 )

      The definition is case sensitive. "Solar System" is our Sun and the stuff in orbit about it; "solar system" is any star and the stuff in orbit about it.

  • If we received broadcast signals from an alien civiliazation how would we respond? We don't have the technology to go there. At best we could send a broadcast toward them. Why would we assume that they are any different? Or is that what they are assuming? That is, our broadcasts will reach them in 750 years and then they will respond quickly so 750 years later we will receive the response?

  • So humanity has 1500 more years to live before the aliens come and destroy us.

    • So humanity has 1500 more years to live before the aliens come and destroy us.

      Only if the aliens can travel at the speed of light

  • You just have to reverse the polarity of the deflector array. Duh, anyone knows that!
  • If intelligent aliens are watching us from afar, they might have checked the spectroscopic signature of our atmosphere, and realized millions of years ago that we live on a temperate planet with a lot of water, and that the high oxygen content in the atmosphere is an indication of life.
    • The volume of the milky way galaxy is about 5.24 * 10^14 lightyears. The volume of earth is about 1.28 * 10^-27. You could fit 4.09 * 10^41 earths within the space of the milky way galaxy. Intelligent aliens are not watching us from afar, we are a needle in a haystack. We are less than a speck of dust when compared with the size of the universe.

    • What's missing is that indications of life might not be strong indications of intelligent life. Depending on the ratio of worlds with life but no intelligence to worlds with intelligent life, and the mean time for intelligent life to develop on a no-intelligent-life world.

  • Lord Hawking should send his probe droids to Hoth. Rumor is that there's a detectable signal from a shield generator.
  • They might not find any so we'll be left alone... Joking aside, they might have something akin to a Prime Directive, and we're not advanced enough in technology to be worth contacting, or not civilized enough (we're still trying to extinct ourselves)

  • An extra 1500 years before catching the attention of aliens is probably not a bad thing. That's more time to prepare defenses. It's hard to guess the nature of the extremophiles which live in space, or the space-faring races which navigate it.

    We shockingly might not be perceived as peers or equals by space-faring races, but as an inferior species. And the history of superior species meeting inferior ones is not all rainbows and unicorns.

  • It feels strange to hear a pessimistic assessment of SETI from Cornell astronomers. Carl Sagan, we miss you...
  • Seriously? (Score:5, Insightful)

    by rgbatduke ( 1231380 ) <rgb@ph y . d u k> on Wednesday June 15, 2016 @08:45PM (#52326145) Homepage

    The "scientists" at Cornell who are getting headlines with this breaking news haven't the foggiest clue how far away the nearest alien intelligent species is from Earth. Possibilities range from living here already among us or lurking in the solar system to "there are no alien intelligent species in the Cosmos", we could be unique. If you assume -- not unreasonably -- that evolution of advanced life requires an extremely unlikely accident -- like a collision with a proto-planet that is just the right size to strip away some atmosphere components and deposit others and rearrange the distribution of massive elements in the developing crust and then produce a moon that initially is very close and produces huge tides, plus a magnetic core, plus the right distance from the right sun, plus the good fortune not to be hit AGAIN just as intelligence is teed up, plus the enormous good fortune of the developing species making it over the self-extinction hump -- we might be alone in the entire galaxy or in very rare company extragalactically, even with a trillion trillion star systems to choose from. Or, the odds could be a D&D 20 sided dice roll per star. We just don't know. There is no evidence, and our theories of planetary evolution and abiogenesis are just that -- theories with very little substantive evidence to support them.

    Then there are the other silly aspects of their claim. It is rapidly looking like a developing civilization is likely to have only a narrow window where they radiate a substantial amount of organized radio wave energy, so one has an even narrower window for retarded detection. Also that emitted (wasted!) energy at its peak is on the order of maybe a megawatt or two in any given channel on its brightest day, and the 1/r^2 law is pitiless. Just one light year away your 10^6 watts are spread out across 4\pi (10^15)^2 ~ 10^31 square meters. Let's see: 10^6/10^31 = 10^{-25} watts per square meter. If you turned an entire planetary surface into a directed antenna, it would have a cross sectional area on the order of 10^14 square meters, leaving you with 10 whole trillionths of a watt receiver power. Sure, why not, a piece of cake we can amplify that and resolve signal from noise -- using a planet-sized antenna and black magic.

    So a better answer is that we will never be visited by space aliens who "pick up our TV signals" any more than we will pick up their signals. If some NEARBY civilization is crazy enough to point a directional, tight beam radio station right at the solar system and pump it with a terawatt or so, sure, maybe we could receive it here. But resolving the waste signal of a civilization order of tens of light years or more away? The amazing thing is that anybody manages to get this sort of thing funded. Simple arithmetic makes a fairly powerful argument that any SETI effort is a complete waste of time and money. No matter how cool -- and dangerous -- it might be.


  • I'm just going to leave this here... []

  • Does this therefore set a timeframe of the order of 1,500 years for us either to colonise other planets, to defend ourselves against unknown aliens of unknown capabilities and intent, or to build the technology for at least some of us to flee?

  • Plenty of time to clean the bathroom and run a vacuum through the place.

  • 1. The authors are completely clueless that some humans have already met at _least_ 4 alien species, let alone the public evidence:

    a) NASA's own footage: (Evidence: The Case For NASA UFOs), [] and
    b) High ranking Government official's testimony Disclosure Project []

    2. They are also completely ignorant that First Contact is tentatively scheduled to happen as early as 2024 and as late as 2040. Some bullshit "theory" will always lose to reality.

    It is no longer a matter of "if", but "when" our mass con

  • Well this certainly explains the 2nd coming of Jesus Christ! 1500-2000 years , give or take....
  • The Milkyway's diameter is 100,000 light years, so even if we were in the center, we'd need at least about 35,000 years for our signal to reach 50% of the volume of the galaxy. If the reply took 17,000 years to get back (probably doesn't originate at the most distant part), then you're talking about 52,000 years. Minus the 50 or so during which "I Love Lucy" has already been traveling.
  • Every civilization goes through a brief period in their history where radio communication is the thing. And then for the next millions of years (if they live that long) they rely on whatever it is that supersedes radio (gamma rays, neutrinos, gravity waves, etc). Everybody knows this. Listening for radio signals is like us watching the plains of Texas for smoke signals from a new native american tribe. Who is doing this today?
  • The only reason I read something with a headline like this is to see what kind of boneheaded assumptions these "scientists" (are astronomers automatically scientists?) make. The idea beings millenia or epochs ahead of us can't travel faster than light is stultifying. Let alone, that they haven't figured out how to communicate in faster modes.
  • Except because of how radio waves travel, it's like writing on a balloon and expanding it...the message becomes distorted to the point that it becomes unrecognizeable once it passes a certain, relatively short range. We could have had alien broadcasts hitting us since we started listening , and we wouldn't know it.
  • Scientists report receiving a long series of pings from space, embedded with a picture of Adolf Hitler and blueprints for a trans-dimensional space travel machine.

  • This is assuming that we have to contact them first. What if they put us here to begin with? As we want to spread out in case of a catastrophic event, maybe they did the same thing and that's why we're here.

    We could also be some kids science experiment.

"Even if you're on the right track, you'll get run over if you just sit there." -- Will Rogers