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So Where Are They?
July 16, 2013 10:11 PM   Subscribe

The Fermi Paradox poses the question, if intelligent ETs exist why haven't they shown up yet. Now a new mathematical study shows that self-replicating probes using sling-shot maneuvers (paper) could explore the entire galaxy in just 10 million years. Perhaps they're already here, hiding, waiting for our technology to reach a level that can de-cloak them.
posted by Long Way To Go (136 comments total) 40 users marked this as a favorite

 
This is proof that we are alone in the universe.
posted by LarryC at 10:13 PM on July 16, 2013 [1 favorite]


For those who are interested, this is basically the plot of David Brin's Existence.
posted by Noms_Tiem at 10:16 PM on July 16, 2013 [3 favorites]


Maybe our solar system is atypical.
posted by Zed at 10:16 PM on July 16, 2013 [28 favorites]


@LarryC

Disagree. We haven't communicated with extraterrestrial organisms for the same reason we haven't communicated with bacteria.
posted by lewedswiver at 10:16 PM on July 16, 2013 [9 favorites]


Disagree. We haven't communicated with extraterrestrial organisms for the same reason we haven't communicated with bacteria.

E.T. is in our assholes?
posted by Foci for Analysis at 10:18 PM on July 16, 2013 [7 favorites]


A Von Neumann machine capable of making copies of itself from whatever it can find in a solar system would most likely require strong AI.
posted by Tell Me No Lies at 10:20 PM on July 16, 2013 [2 favorites]


Zed - that deserves an FPP, if it hasn't had one already.
posted by Pruitt-Igoe at 10:22 PM on July 16, 2013


Foci... there are many people the past 60 years who have said exactly that... ;-)
posted by lewedswiver at 10:22 PM on July 16, 2013 [3 favorites]


It makes me wonder - and I know this isn't going to be a remotely original thought - but humanity has existed for a blink of a second by the timescale of Earth, let alone by the standards of the universe as a whole. Who's to say that intelligent life hasn't arisen elsewhere and then long since died out? We're not just alone - we're last.
posted by ZaphodB at 10:31 PM on July 16, 2013 [3 favorites]


Maybe there are severe downsides/risks to creating self replicating probes that become apparent when the technology is advanced enough...so, civilizations capable of creating them end up not doing so....
posted by asra at 10:33 PM on July 16, 2013 [1 favorite]


Maybe our solar system is atypical.

I would really like to understand the methods of finding solar systems with planets before using the current list as a guide for anything.

Several close in planets that are the size of Jupiter and that orbit every couple of days seem like the kind of thing that would catch your eye pretty easily when you go exo-planet hunting.
posted by Tell Me No Lies at 10:36 PM on July 16, 2013 [6 favorites]


"Paradox" is a bit of an overstatement, isn't it? Maybe "Fermi problem" was already taken up by the how many piano tuners in New York type of question.
posted by thelonius at 10:43 PM on July 16, 2013 [3 favorites]


Maybe our understanding of the universe's speed limit is complete and correct, and interstellar distances are practically insurmountable for any lifeform remotely like us.
If so, the question of whether they exist is moot.
posted by rocket88 at 10:43 PM on July 16, 2013 [16 favorites]


I forgot the obligatory XKCD
posted by Long Way To Go at 10:43 PM on July 16, 2013 [7 favorites]


I recall that a fleet of these probes arrived on Earth in 1979 and was promptly swallowed by a small dog.
posted by smrtsch at 10:43 PM on July 16, 2013 [25 favorites]


I think once a civilization gives birth to an Ayn Rand it's pretty much all she wrote (zing!). A gruesome extinction is only a few generations away at that point. The interesting question then becomes why does Atlas always shrug?

On a more serious note, our only real experience with intelligent species shows that hatred, superstition, and selfishness--combined with technological progress mostly driven by seeking increasingly clever ways to kill other members of the same species--seem to be the predominant traits. That doesn't bode well for board meetings in beige rooms at the speeds beyond light.
posted by maxwelton at 10:44 PM on July 16, 2013 [1 favorite]


Maybe human intelligence is unique. It seems unlikely, but perhaps the desire to build stuff and explore space is not at all common. We may already have encountered other beings with a sentient concept of self - the great whales, for example. Maybe the use of language to transmit precise information is unique. In short, perhaps we place to high a value on the human concept of intelligence. Not to romanticize, but indigenous folk typically recognized the uniqueness of animals and plants, something our rational, Cartesian culture has basically trashed. What if the ability to make and create is not the point? Judging by how rapidly humanity has emerged and transformed the planetary ecology, on a galactic scale perhaps the human concept of intelligence does not provide a sustainable competitive advantage.

It's more interesting to think that whales are true cosmic template. Or the octopus. Self-awareness perhaps, but no real ability or inclination to modify or subjugate their environment.
posted by KokuRyu at 10:50 PM on July 16, 2013 [14 favorites]


Ten million years is a really fucking long time.

This doesn't disprove anything. It just proves that, if an alien society has ever existed, and if they had the intelligence to develop self-replicating probes and slingshot them into space (something we ourselves are not yet intelligent enough to do), and if they decided to do so, then it would take TEN MILLION FUCKING YEARS for said probes to explore the entire galaxy.

I mean, there could still be hundreds of planets of folks just like us (but maybe with bumpy foreheads?) who simply haven't gotten around to doing this self-replicating probe thing. Just as we ourselves haven't.

I just hope they're picking up some early jazz radio broadcasts and smiling to themselves. Someday. Someday.
posted by Sara C. at 11:06 PM on July 16, 2013 [7 favorites]


KokuRyu: the human concept of intelligence does not provide a sustainable competitive advantage

If you're interested in this idea, you might enjoy Peter Watts' (now creative-commons'ed) science fiction novel Blindsight. I won't spoil how it ties in, but the Wikipedia article about it mentions it in passing.
posted by curious.jp at 11:08 PM on July 16, 2013 [19 favorites]


I like to believe there is a sophisticated and friendly interstellar civilization out there, simply waiting for us to reach the level of technological or social development where we qualify for contact.
posted by bowline at 11:11 PM on July 16, 2013 [2 favorites]


Ten million years is a really fucking long time.

Ha. I had just come in to post that on a galactic scale, 10 million years is pretty short. For example, it takes ~230 million years for our solar system to obit our galactic center.
posted by sbutler at 11:16 PM on July 16, 2013 [10 favorites]


My guess is that plenty of intelligent life exists, but the physics of the universe is harsh enough to keep it out of contact with each other. The speed of light seems to be absolutely fundamental to the universe, to the point where the concept of causality seems to depend on it being inviolate, so it seems entirely possible there really is absolutely no way to cheat it at all. So you are left with slow ships. But space is harsh; can you really make equipment that lasts that long, out there? Sufficiently complicated computers that aren't fried by the radiation over the years? Maybe it can't be done.

And even if it's theoretically possible, that doesn't mean it's practically possible. It has to be achievable using the resources an intelligent species can actually get. Rockets might be the best you can get; maybe there's no better form of propulsion for liftoff and nothing strong enough to make a space elevator exists. So in-system mining might be so ruinously expensive that it's never worthwhile. Then, you are limited to the resources of a single planet. And you have to support a huge civilization to have the science necessary to do any of this. Maybe interstellar crafts are so expensive that they're just never built. A couple of overachieving worlds send out one probe to a nearby star, and that's it.

Also, I think the idea of something like a complex, self-replicating probe might require a superintelligence to design it. Such an intelligence might not be possible (intelligence might not scale up well).

So, basically, I think the most likely possibility is that there is life all over the galaxy and intelligent life here and there, but it's permanently held apart by the fundamental nature of the universe. It's somewhat sad, but when you consider what happened when human cultures came into contact for the first time, maybe it's for the best....

And it it helps, I think the technology to detect lifebearing and even intelligent-lifebearing worlds is feasible.
posted by Mitrovarr at 11:24 PM on July 16, 2013 [32 favorites]


Yes, galactically it's short. But in terms of the lifespan of the lifeforms that would need to create a program like this, it's astronomical. Certainly in "first contact" terms, it's an amount of time so big as to be meaningless.

(In addition to the many interesting theories people have already mentioned, I also like thinking of aliens visiting earth four or five million years ago, saying, "Hm, Class M Planet, temperate climate, plenty of flora and fauna, but unfortunately no intelligent life...")
posted by Sara C. at 11:24 PM on July 16, 2013 [7 favorites]


It is interesting to think of how many hidden premises or assumptions are needed to make this go through as a formal argument. The idea that advanced technical civilizations usually just keep on progressing and become more and more advanced until they can do interstellar travel comes to mind.
posted by thelonius at 11:24 PM on July 16, 2013 [8 favorites]


10 million years is what... .25% of the estimated number of years before our solar system is eaten by the sun as it engulfs everything during its ever expanding life?

One Quarter of One Percent.
------------------------------------

To relate to the past, Wikipedia gives this little overview:

20 Ma First giraffes, hyenas, bears and giant anteaters, increase in bird diversity.

15 Ma Mammut appears in the fossil record, first bovids and kangaroos, diversity in Australian megafauna.

10 Ma Grasslands and savannas are established, diversity in insects, especially ants and termites, horses increase in body size and develop high-crowned teeth, major diversification in grassland mammals and snakes.

6.5 Ma First hominin (Sahelanthropus).

6 Ma Australopithecines diversify (Orrorin, Ardipithecus)
posted by symbioid at 11:25 PM on July 16, 2013 [2 favorites]


My other favorite idea is that aliens have had contact with dolphins for years and we're just not privy to it at all.

It's entirely possible that we're already part of some kind of Federation Of Planets, but nobody has bothered to inform the Hairy Fish Who Walk.
posted by Sara C. at 11:25 PM on July 16, 2013 [25 favorites]


the physics of the universe is harsh enough to keep it out of contact with each other.

Or maybe just out of contact with us.

What if there's a lively community of interstellar life, but it's all clustered around a few star systems that happen to be near each other and absolutely chock-full of inhabitable planets and moons, which made developing interplanetary relationships worth doing? What if we're the galactic equivalent of Easter Island or the deepest Amazon?

There are just so many possibilities for what the situation actually is that it seems horribly dull to assume we're alone.
posted by Sara C. at 11:33 PM on July 16, 2013 [10 favorites]


> We're not just alone - we're last.

That's unlikely. Sol is a third generation star: its first forebearers, born 750 million years after the Big Bang, most likely absorbed all the heavy elements, and burned too brightly and briefly to sustain the development of life. Second-generation stars, born from the detritus of the first, have a greater chance of being the center of a civilization, and third-generation stars like our own greater still. There are plenty of active stellar hatcheries bringing forth further generations: the Pleiades are a good example of that. The Universe has an awful lot of time left to give before the last fires go out.

I think back to just 20 years ago, when we weren't even sure that other planets existed outside our own solar system. Theoretically we knew they were possible, even likely, but we had no evidence for them. Today, we're closing in on 1000 confirmed exoplanets.

100 billion stars in our galaxy. At least 100 billion other galaxies, each with an equal number of stars. Each of those stars with planets: even the outliers, like white dwarves and binary clusters. Again, no evidence of life on any of them, but theoretically possible, even inevitable.

Personally I think there's several possible reasons behind the lack of contact:
  1. The flowering of intelligent civilization may be fairly brief: they either extinguish themselves or turn inwards into a Sublimed non-biological Shangri-La from where the outside universe no longer holds any interest. Or, as Sara C. mentioned above, they exist in a Firefly-like pocket 'Verse that holds enough possibilities for a thousand generations of exploration and colonization, and have no need, or desire, to explore further.
  2. Related to the above, self-replicators may be seeded through the galaxy, but miss our civilization entirely: if a probe arrived a million years ago it likely would not have noted Homo habulis as being particularly interesting. We've only been able to communicate with radio for a little over 100 years: what's the chance a probe finding us in that time frame?
  3. Self-replication may well be against some kind of galactic Prime Directive: personally I would be very hesitant to send out anything into the universe with the ability to use matter it discovered to replicate itself infinitely.
  4. The majority of intelligent life in the universe may be xenophobic and inimical, and civilizations have made the wise decision not to broadcast their location.
  5. The solar system may be part of a galactic zoo. Plenty of opportunity to cooly observe us from the Oort cloud, which even the Voyager probes won't cross for at least a few more decades. We still kill each other with chemically-propelled bits of lead, for goodness sake: what interstellar civilization would want to give us the time of day?
posted by Bora Horza Gobuchul at 11:44 PM on July 16, 2013 [38 favorites]


The reasons we can't see aliens include stuff likeThe aliens problem sounds a bit like the search for the gods, that gaggle of superbeings who absolutely mathematically have to exist, who are watching us and judging us, who can be seen and understood by the right people in the right frame of mind, and who listen to us and who will be back for us. There is no reliable evidence that the intended recipients exist, but the faithful insist that they have to exist, some claim to have seen or heard them but can't ever prove it, and believers will not be argued out of their positions, though they may adjust their stances to maintain their footholds.

It's all fine to me -- keep searching the heavens -- as long as we don't gamble away a lot of time and money on the big unknown when there are big knowns to take care of right here in Eden.
posted by pracowity at 11:56 PM on July 16, 2013 [1 favorite]


Wasn't there just recent discussion about an island over by the Philipines(?) that regular people are supposed to stay away from and the natives are openly hostile to incoming mainlanders? I like to think that Earth is off limits to aliens until we are capable of sustained space travel to go visit the rest if the universe's sentient creatures. Of course there are poachers and thrill seekers who come visit occasionally which is why we have alien sightings and abductions.
posted by HMSSM at 11:59 PM on July 16, 2013 [1 favorite]


Evolution has developed many measures to protect against malignant mutations just as human technology has built in safeguards against corruption in electronic systems, so it is reasonable to assume that SRPs would be protected in a similar, and possibly better fashion.

The author's physics are interesting but that statement betrays a not-so-strong understanding of biology or how evolution works, where "malignant" is a mostly subjective descriptor.

The only thing evolution "cares" about is succeeding at replication, above all else. Cancer cells are a good demonstration of how the process of evolution (selection) allows certain mutations to prosper at the expense of others within a population. Cancerous mutations are evolutionarily successful, but they are not particularly beneficial to the host.

One could imagine a pool of SRPs similarly developing a mutation that would look "malignant" to us, in terms of an usurped "mission" or other program — say, no longer exploring new planets on our behalf — but could make that particular set of SRPs evolutionarily successful, in terms of searching out and spreading itself to as many planets as possible.
posted by Blazecock Pileon at 12:01 AM on July 17, 2013


My favorite answer is bandwidth. Travelling far from your homeworld is much like driving way out in the sticks - your internet connection would suck. Sublight interstellar travellers are cutting themselves off from their own culture.
posted by justsomebodythatyouusedtoknow at 12:01 AM on July 17, 2013 [5 favorites]


My guess is that plenty of intelligent life exists, but the physics of the universe is harsh enough to keep it out of contact with each other.

This is my guess too, and I find it pretty viscerally disheartening. I guess maybe I temper this notion with a somewhat fantastical quasi-religious belief in something like Panpsychism. I tend to think that complex processes -- whether they be physical or chemical or consist of synaptic activity in the brain -- are, in some sense, self-aware. Maybe not in a way we could ever really understand or communicate meaningfully with but, still, somehow self-aware, and that this self-awareness is a property of the physical, material universe as it unfolds in the dimension of time.

I know it's not a verifiable theory, which is why I consider it a fanciful notion and/or something in the realm of religious belief. But it does help lessen the pain of the tragedy of the notion of life like ours being abundant but unable to ever possibly communicate with our neighbors in the next star system. Of course, as others in this thread have pointed out, the neighborhood itself could also be an incredibly hostile one, given how hostile we are to one another.
posted by treepour at 12:15 AM on July 17, 2013


We haven't communicated with extraterrestrial organisms for the same reason we haven't communicated with bacteria.

We communicate with bacteria all the time. How else could we cooperate so beautifully with our gut flora? We co-evolved with them!

It doesn't seem impossible to me - given the diversity of life on this planet alone - that we could be defining communication and intelligence so narrowly that we miss it even when we are looking as hard as we can. We didn't even know that bacteria talked to each other until the mid-1960s. So it's not hard for me to imagine intelligent life that sends out signals in a format it finds most compelling but that is totally unrecognizable to us right now.

The speed limit may well stop them from visiting us, or may mean they visit at the wrong time (before or after we're the loudest intelligent life on the planet, or before or after we're able to figure out they're there to say hi), but from a purely probabilistic perspective, I gotta think Earth isn't the whole enchilada.
posted by gingerest at 12:19 AM on July 17, 2013 [1 favorite]


This is why I doubt the Singularity; intelligent machines could handle thousands of years of transit time between star systems with ease, and the asteroid belt should be swarming by now.

Of course, maybe they've been and gone, and we'll get up there and find nothing but mined-out hulks-- and be stuck here.
posted by jamjam at 12:31 AM on July 17, 2013 [1 favorite]


We just haven't waited long enough.
posted by Ironmouth at 12:48 AM on July 17, 2013


The interesting thing about slingshot maneuvers for Von Neumann probes, to me, is that it hasn't been modeled before -- and that it makes a difference. I guess I'd assumed earlier studies included 0.1c drives with perfect maneuvering.

The real eye-opening moment in the paper, for me, is the section on information propagation and race conditions (section 4.1, p.7 of the PDF). I had also assumed Von Neumann probes would already know where they're all going, or would otherwise somehow have perfect knowledge of where the other probes are. As the paper points out, that's unrealistic: information doesn't travel instantaneously, of course. Also, if we're talking a scale of 108 years, new stars could easily be born within the span of a probe program. (They're unlikely to harbor life if they're that new, but the point is to visit every star, not just stars of a given age.) Even if probes are designed to leave beacons letting other probes know a system has already been visited, it's easy to imagine scenarios in which that beacon system could fail and a star could therefore be visited by multiple probes. Less-than-perfect propagation of information therefore implies to me that even if probes avoid excessive multiplication, it's still very possible for have excessive contact. ("Hello, has anyone stopped by to tell you about the benefits of a really good set of the Encyclopedia Galactica?" "Yes, goddamnit! We've had salespeople beating down our door for the past three millennia! You're the fifth one this century! Now get lost!")

By the way, Robert Freitas' website is well worth checking out. It includes several interesting articles ("Interstellar Probes: A New Approach to SETI", "If They Are Here, Where Are They?: Observational and Search Considerations", "A Self-Reproducing Interstellar Probe", "The Search for Extraterrestrial Artifacts (SETA)", "Extraterrestrial Intelligence in the Solar System: Resolving the Fermi Paradox", and many more) as well as an entire book, Xenology.
posted by jiawen at 1:15 AM on July 17, 2013 [12 favorites]


My simple theory: We haven't communicated with aliens because if we had, we'd be dead.

It is an extremely hostile Universe out there. Luckily, hiding out on the edge of this non-descript galaxy has allowed us to avoid detection so far. Our weird location is not a coincidence. It is yet another of our lucky breaks. Perhaps we have even had some close encounters where an intergalactic spaceship had to turn around at the last moment on some other mission.

We're Great Plains indians. And we have deduced that since nobody is out here hunting buffalo too, we must be the only civilization on the planet. Meanwhile, ships are crossing the ocean...
posted by vacapinta at 1:30 AM on July 17, 2013 [8 favorites]


WE COME IN PEACE.

WE BRING GREETINGS FROM A FRIENDLY SPECIES.

DO NOT FEAR. WE SHALL NOT HARM YOU.

THIS IS PROBE 2418-B, ON A PEACEFUL MISSION.

WE ARE NON-HOSTILE AND SEEK TO ESTABLISH FRIENDLY RELATIONS.

WE WISH TO LEARN MORE ABOUT YOU. PLEASE TRANSMIT DATA.

THIS PROBE IS NON-HOSTILE. DO NOT ATTACK.

WE COME IN PEACE.
posted by C^3 at 1:44 AM on July 17, 2013 [19 favorites]


“Turtles don’t really die of old age,” Dr. Raxworthy said. In fact, if turtles didn’t get eaten, crushed by an automobile or fall prey to a disease, he said, they might just live indefinitely.

Turtles have the power to almost stop the ticking of their personal clock. “Their heart isn’t necessarily stimulated by nerves, and it doesn’t need to beat constantly,” said Dr. George Zug, curator of herpetology at the Smithsonian Institution. “They can turn it on and off essentially at will.”

Turtles are also ancient as a family. The noble chelonian lineage that includes all living turtles and tortoises extends back 230 million years or more, possibly predating other reptiles like snakes and crocodiles, as well as birds, mammals, even the dinosaurs.


NYTimes article

I propose that turtles are descendants of a space faring alien species that arrived after travelling in stasis or cryo-sleep in a turtle shaped mother-ship. We are their progeny, and turtles are our ancient alien ancestors that plod amongst us.
posted by panaceanot at 1:47 AM on July 17, 2013 [9 favorites]


How can equations and formulas suggest this? What makes this claim more plausible than someone just making stuff up? I'm not asking out of doubt, I'm genuinely curious. I registered to the site just to ask this.
posted by Mitochondrial_Steve at 1:47 AM on July 17, 2013 [1 favorite]


I love the way the study glosses over the minor technical detail of coming up with a self-replicating autonomous probe, as well as the more important issue that any civilization with that kind of technology would obviously devote all of its resources to the construction of novel types of sexbots and would have zero desire to contact other, potentially icky, life forms.
posted by Dr Dracator at 1:51 AM on July 17, 2013 [3 favorites]


I propose that turtles are descendants of a space faring alien species that arrived after travelling in stasis or cryo-sleep in a turtle shaped mother-ship. We are their progeny, and turtles are our ancient alien ancestors that plod amongst us.

I propose tardigrades as creatures from another planet. Seriously, read the Wikipedia article. These little guys can survive outer space.
posted by vacapinta at 1:53 AM on July 17, 2013 [3 favorites]


They've been here since the 50's and they are Gorgeous!
posted by mikelieman at 1:56 AM on July 17, 2013


I love the way the study glosses over the minor technical detail of coming up with a self-replicating autonomous probe

Yes: if you're going to help yourself to that, why not give yourself FTL, or super long-distance mind-scanning that means you can check out the entire galaxy from your armchair?
posted by Segundus at 2:28 AM on July 17, 2013


Well, kidding aside - self-replicating autonomous probes are not theoretically impossible, just very hard. The aim of this kind of study is to set a very rough envelope of possibilities, not really to discuss specific implementations. In that sense, negative results are more useful than positive ones - we don't know if a SRP will ever become a reality, but it would be good to know if it's not worth trying.
posted by Dr Dracator at 2:41 AM on July 17, 2013 [2 favorites]


The Planetarium Hypothesis is one of the more depressing scenarios.

I've never been particularly convinced by the Fermi Paradox. It suggests that other civilizations will be operating with technology on a par with our own or that they're going to commit to actions that we deem probable.
posted by panboi at 2:51 AM on July 17, 2013 [2 favorites]


I note with interest that our technological civilization is at most 5000 years old, we only have clear evidence of human cultural activity going back 50-70,000 years, and our species of hominid is at most 250,000 years old ... yet we've already triggered a major extinction event.

Most species seem to have a life expectancy on the order of ~10MYa, but we have managed to massively destabilize the biosphere we coevolved with in significantly less than 0.01MYa. And note that we don't yet know how to build a portable biosphere able to sustain human life ab initio: the closer you look at the problem, the harder it gets.

Conclusion: our kind of tool-using intelligent culture, which is what we're interested in when we talk about extra-terrestrial life, may actually be a highly unstable evolutionary dead-end that never lasts long enough to build Von Neuman probes.

See also: Olduvai theory.
posted by cstross at 3:00 AM on July 17, 2013 [21 favorites]


The most likely hypotheses to me are the most depressing ones, in that it seems unlikely that we are the only planet on which life developed, but instead intelligent, civillised life is essentially fleeting. Our civillised society is massively inter dependent and short lived. Ancient civillizations have already collapsed without managing to find much progress, and much of the scientific advancements we've made so far are luck based.

To get to these point we have eaten up resources we won't get back. Getting out of orbit is really rather expensive, and the benefits are nearly vanishing. If we don't do it before some large event (a super volcano, a stray meteor, the new ice age) occurs then we might well miss our shot entirely.

Even if we do spread across the solar system, our current understanding of physics indicates that getting much further will be even harder!
posted by Cannon Fodder at 3:13 AM on July 17, 2013 [3 favorites]


A Von Neumann machine capable of making copies of itself from whatever it can find in a solar system would most likely require strong AI.

Or maybe just DNA.
posted by gjc at 3:20 AM on July 17, 2013 [1 favorite]


gjc: probably not DNA. DNA transcription relies on the sense/antisense sequences being held together by hydrogen bonds (which are easily cleaved and rejoined by transcriptase enzymes): trouble is, hydrogen bonds are also easily mangled by ultraviolet light, of which there is rather a lot in interstellar space. As we're looking at interstellar cruise times on the order of tens to hundreds of thousands of years, the probability of a DNA sequence surviving the voyage unmangled is fairly low.
posted by cstross at 3:37 AM on July 17, 2013 [2 favorites]


cstross: The DNA could be self-repairing. This is not unheard of. Once again, Tardigrades
posted by vacapinta at 3:41 AM on July 17, 2013


My simple theory: We haven't communicated with aliens because if we had, we'd be dead.

I imagine just an unambiguous "hello" from the stars has the potential to trigger a devastating war or two here on Earth. Even putting aside the obvious question of whether or not to respond (are they hostile? are they friendly? will they eat our livers because our livers are like candy to them?) such contact would have a huge impact on our understanding of the Universe and our assumed place within it that's assured to generate heated debate if not outright conflict. Whether or not they exist, the aliens are really doing humanity a favor by not contacting it.

You're welcome
posted by RonButNotStupid at 3:46 AM on July 17, 2013 [2 favorites]


Perhaps aliens have been here for ages but they're just keeping silent.
posted by plastic_animals at 3:56 AM on July 17, 2013


Now a new mathematical study shows that self-replicating probes using sling-shot maneuvers (paper) could explore the entire galaxy in just 10 million years

This is proof that we are alone in the universe.


That's ridiculous. Our one known example of a species that could conceivably do this, hasn't. So why are we requiring hypothetical other aliens to do so and the concluding they must not exist?
posted by DU at 3:59 AM on July 17, 2013 [3 favorites]


So ... let me get this straight.

The idea here is that first, we are not the only living things in the Universe. Seems reasonable, it'd be pretty bizarre if conditions here were completely unique in the entire Universe, and there's probably also some play as to what conditions allow for the formation of life.

But the Universe is freaking huge. There could be things elsewhere in the Universe who would never, ever have any chance of reaching us in billions of years of exploration. So let's restrict that idea to, we are not the only living things in the Milky Way Galaxy. There are 300 billion stars in this Galaxy alone, that's a lot of chances to set up the necessary conditions.

But how many of them actually fulfill those necessary conditions? Hard to say. We only have our own example to go by, so we don't really know what would prevent or encourage other life. But there's probably a lot we can reasonably take out. Constantly bombarded by potentially sterilizing radiation, as most places are near the galactic center? Probably not so good. No planets? Probably not so good. Only planets which are really close in, really far out, can't maintain an atmosphere, and so on? Probably not so good. Been around for less than a billion years or so? Probably not enough time for anything much to happen lifewise. Etc., etc., etc.

But hey, that probably leaves a lot of systems where life might have potentially evolved. Probably.

But now take out the ones where, for whatever reason, it didn't do so anyway, or hasn't yet. It took earth roughly a billion years to get past that phase.

Now take out the ones where it hasn't gotten beyond extremely simple organisms - a period that lasted around 3 BILLION YEARS here on earth.

Now take out the ones that have evolved complex organisms, but not sentient ones capable of technology - a phase that lasted well over half a billion years here.

Now take out all the ones that are uninterested or incapable of exploring other stellar systems. (This very well might include every single group that evolved around a metal-poor Population II star, so there's another huge chunk off the list and ALL of the oldest stars that have had the most time to develop life.)

Now take out all the ones that are interested and potentially capable but don't have the means of doing so yet and might never (like, you know, us.)

Now take out all the ones that never developed this technology we don't even for certain know is possible or desirable, then take out all the ones that didn't happen to take a look at earth during the EYEBLINK's worth of time that we MIGHT have noticed such a thing ...

And people think the question is, "So where are they?"
posted by kyrademon at 4:02 AM on July 17, 2013 [6 favorites]


...nobody has bothered to inform the Hairy Fish Who Walk.

I love the idea of dolphins calling US fish.
posted by DU at 4:02 AM on July 17, 2013 [3 favorites]


Aren't mushroom spores from outer space?
Also, I thought the aliens were already here, that's why there are cave paintings of spaceships.
posted by windykites at 4:32 AM on July 17, 2013


Radio signals attenuate like nobody's business, and humans are getting better about quiet signals, as it lets us use radio communications for more neat stuff. The idea of aliens watching "I Love Lucy" on the original broadcasts a few hundred years from now is just not going to happen... and that was a really strong signal comparatively. Our modern radio footprint is much quieter, as efficiency has increased.

Our attempt to deliberately contact others has been pretty pitiable. Not much money or manpower is devoted to sending them or listening for them.

So, if there are other civilizations out there, they're probably like us, and not spending a lot of effort on first contact via radio transmission. There are other methods, including the aforementioned probes. But when and how should a proble reveal itself? Will it have the autonomy to reveal itself, or has it sent a message home (via another probe) asking permission for contact - permission that could take centuries or millennia to reach it?

Another possibility is that slower-than-light communication is indicative of a civilization that doesn't have anything to sell or steal yet - once we figure out the ansible or subspace communicator or interdimensional portal or unleash the Nyan Cat, that's when we're in for some fun.
posted by Slap*Happy at 4:36 AM on July 17, 2013 [1 favorite]


Why would they bother?

What do we have that they would want?

Intelligence? If they are exploring the cosmos to that degree, they win already. We have nothing to sell.

Resources? Same star dust here as everywhere else. Better planets closer to home for shopping.

To help us? Do what?

To study us? Again, to what end? We aren't all that impressive. Our world leaders wear shovel hats (the Pope), get in trouble for routine mating (Clinton), are pathological (Pol Pot, Adolph Hitler, the Younger GW Bush, Kim Jung Un and Il).

We can do stuff they can't? Like interstellar travel.

Honestly, the odds heavily favor intelligent life in the universe. The same odds heavily oppose it wandering around causing trouble or spreading good.

Nah, we're up to our asses in self-directed suicide. We will sink or swim via our brains and on our own. It's a godddamned miracle we didn't scorch this place in the post-WW2 nuclear standoff era. As a species, we're still worshiping dog poop and calling it God and killing everyone who doesn't find it as holy as we do. A tiny fraction of humanity, of which I am not a part of said fraction, is doing anything worthwhile and even saving them is questionable. We can't even do the celestial equivalent of car maintenance or cleaning our room or caring for our young. Aliens, if they are smart enough to be here, would be unimpressed with what we do, have done, will do, and have. We are no more or less than froth on a sea of varied protoplasm. We're deluded if we think we're any better than yeast in the eyes of stellar visitors.

Remember, according to cosmological theory, we are the dust of prior stars (heavy elements as opposed to H ahd He.) We may be iteration 10? This shiz been going down long time.
posted by FauxScot at 4:41 AM on July 17, 2013 [4 favorites]


Here's a nearby place that almost certainly housed life.

What I find hilarious is that we're even debating if it could have happened? It's like exploring the empty mall complex and speculating if there was ever a Gap there?
posted by FauxScot at 4:48 AM on July 17, 2013 [2 favorites]


Both the statements "They wouldn't be interested in finding/talking to us because ..." and "They would be interested in finding/talking to us because ..." are pretty much ridiculously speculative in the absence of any information whatsoever.

I mean, I can't even figure out what the hell the cat is doing sometimes, and our two species share 90% of our DNA, evolved from a common ancestor just 90 million years ago, and have been living together as roommates for 4,000 years. The motivations and desires of a creature we have never even encountered, that went through an entirely different evolutionary process on another planet altogether, are simply NOT going to be determinable by thinking about it real hard.
posted by kyrademon at 5:02 AM on July 17, 2013 [14 favorites]


We don't even know if "life" is a thing, like "rain" or "lightning," that happens whenever commonly-found conditions are present. It may be an incredibly unlikely fluke even in the friendliest organic soup. Setting aside the issue of life in general, non-microscopic life may be a cosmically rare holy-shit kind of thing. I am as science-y as they come, Sagan and Shklovskii was like my bible when I was a kid, assumption of mediocrity and all that, but the reality is we just have no idea.
posted by gubo at 5:02 AM on July 17, 2013


I've always found the notion that, if they existed, ETs would (of course!) contact us, to be blindingly arrogant.
posted by Thorzdad at 5:04 AM on July 17, 2013 [6 favorites]


We still haven't mapped all of Antarctica. The probes could be sitting on the moon waving flags and we wouldn't notice them.
posted by odinsdream at 5:09 AM on July 17, 2013 [7 favorites]


We know so little about life and the environs where it may exist in the universe that these speculations are almost entirely disconnected from the grounding in fact that science depends on. But, since we're speculating wildly my take is: life is fairly common, intelligent life less so, but intelligent life that develops technology for manipulating the electro-magnetic spectrum and travelling in space is both rare and it is unlikely that the lifespan of such civilizations will overlap with others.

But again, these "theories" need a lot more data. We need more planet finder telescopes.
posted by audi alteram partem at 5:32 AM on July 17, 2013 [1 favorite]


For some measures of 'intelligent,' we have other intelligent beings on this planet already. Take octopuses. There is mounting evidence that they are really, really fucking smart. But I say 'mounting evidence' because, although we can observe their behavior, we can't communicate with them nor they with us, and their desires are so totally incomprehensible to our mindsets that even if we COULD communicate, we might not have any common reference points that would make understanding possible. We don't even have all of our senses in common.

And, octopuses are our brothers. We have a common ancestor.

It seems like the height of human-centric arrogance to think that "intelligence" necessarily implies "has the type of highly organized social structure that leads to advanced industrial development, has the desire to attempt to leave the planet, has the mineral resources to do so, can conceptualize of other intelligent life forms from other planets, attempts to make contact with those life forms, and is successfully able to do so." There might be intelligent life, but that doesn't mean the Vulcans are gonna come whizzing by broadcasting radio signals.
posted by showbiz_liz at 5:34 AM on July 17, 2013 [10 favorites]


I don't know if this is explicitly taken account of in the formulation of the Fermi paradox but, even if intelligent life evolves independantly on several planets, _some_ civilization must be the first to progress to the point where it begins to wonder where everybody else is but can't detect anything yet. Xenoarchaeologists from later civilizations will probably find all the headscratching hillarious.
posted by Dr Dracator at 5:35 AM on July 17, 2013 [1 favorite]


The Fermi Paradox is not a scientific idea, although Fermi was a great scientist. Interstellar travel is so remote on our development timeline that discussing the details and the pros and cons and the prime directives falls into the category of the world being a lot stranger than we can understand. If and when humans can travel to other star systems the paradox may no longer be.
posted by bukvich at 5:37 AM on July 17, 2013


I challenge anyone to look at a picture of the Hubble Ultra Deep Field and still claim that we are alone in the universe.

The sheer number of galaxies in a tiny speck of sky makes that... unlikely.
posted by lydhre at 5:39 AM on July 17, 2013 [3 favorites]


Life is probably pretty common. But radio-building life that survives long enough to send a signal to another populated solar system and receive a response? Probably pretty rare.

The most sucessful lifeforms on this planet are bacteria; no reason to assume intelligence is a long-term advantage.
posted by spaltavian at 5:49 AM on July 17, 2013 [4 favorites]


It's all fine to me -- keep searching the heavens -- as long as we don't gamble away a lot of time and money on the big unknown when there are big knowns to take care of right here in Eden.

Looking at the budget numbers, I'm doubtful there's any risk of that happening (not to mention the unpredictable practical benefits that emerge from blue skies, or in this case black skies, research).
posted by audi alteram partem at 5:54 AM on July 17, 2013


If we ever run into life out there it will probably end up being decendants of these self-replicating AI machines that we pretend we'll be able to build someday, like in the movie Screamers.
posted by monkeymadness at 6:06 AM on July 17, 2013


We originally assumed we were the center of the universe, then that we were the only solar system, then that our solar system was in the only galaxy. Until recently it seemed that planets were rare.

Every time that we've had the wherewithal and the inclination to detect some quality in the universe that has previously marked us as unique, we've found that we are far less central and far less rare than we had imagined.

So the idea that life and intelligence is unique, or even rare, is probably dead wrong. If we haven't detected it yet, the problem is almost certainly with our detectors, not life. If a heuristic like the Fermi Paradox says that we should have detected it by now, then heuristic is probably making an incorrect assumption.
posted by wotsac at 6:07 AM on July 17, 2013 [2 favorites]


From the Spooky Action at a Distance department, what if our 3D-centric conceptions of travel are too limiting?

What if an alien civilization could create subtle organic probes through more efficient, space-time-information-jumping features of the universe, like quantum entanglement?

What if they already did it on Earth, using it to influence the local organic development to hitch a ride on whatever life was mobile enough to study the planet, while it reported back the information to the aliens without the direct observer knowing?

What if they got greedy and tried to "help" the local life forms be better acquirers and processors of information, but their long-distance instructions went awry, like any good game of inter-galactic "telephone", resulting in an uncontrolled (on an astrological time-scale) replication frenzy?

What if earthly humans are that unintended byproduct, and we have spent the last 1 million-odd years being very good replicators and consumers of information but without developing any natural instincts towards improving the model from which we came?

What if they know they accelerated our development but their resurgent morality says they can't interfere again for fear of making worse what happened, so they're waiting to see if we either just burn out or end up figuring out how to really make it in this amazing and expanding universe?

What if all of this was because two alien galacto-anthropologists got drunk one night and argued about just how long this exploration-cataloging thing was going to take (I'm getting bored!), ending the night in a bet for 1 *blaring noise* (inaudible currency denomination the equivalent of 0.02 Earth-USD) that Fred could make this work in 1 million years rather than Barney's 10 million?

That last part, of course, guarantees there are thousands of just-as-f'd-up planets as ours out there. Let's get to work, people.
posted by bafflegab at 6:21 AM on July 17, 2013


as long as we don't gamble away a lot of time and money on the big unknown when there are big knowns to take care of right here in Eden
Eden was in Tanzania. Life expectancy there just topped 60 years for the first time. I'm glad their knowns are starting to get taken care of, but I'm even more glad most of our ancestors opted for the big unknown instead. I hope we'll continue doing so.
posted by roystgnr at 6:25 AM on July 17, 2013 [1 favorite]


I'm an alien.

I've already beamed the music of REM, Radiohead, Queen, Pink Floyd, and the Beatles back to my home planet.

Along with copies of The Sopranos, The Wire, and Breaking Bad.

All we need are those last 8 episodes so we can finally know if Walt or Jesse will die or what.

There is not much else of value here.

Maybe puppies. Puppies are cool.
posted by ELF Radio at 6:37 AM on July 17, 2013 [4 favorites]


Dammit C^3! I'm never fast enough to get the obvious Star Control joke in first.

But yes, self-replicating probes. What could possibly go wrong? Certainly not hours and hours and hours of frustration just as the plot of the game is starting to reveal itself and all of a sudden these tumbling ruby-studded barbells are frying you like the Emperor at the end of Jedi and trying to interpret cryptic clues or foregoing tech upgrades on your Precursor ship to hopefully buy a hint from the Melnorme, but maybe you should just get the tech upgrades instead so you can fight them, after all they give a good amount of RU for scrap and FUCK! running out of fuel right before you get back to the starbase and here they come. WHAT THE FUCK IS A SLYLANDRO? I landed on every planet in that goddamn system.
posted by [expletive deleted] at 6:40 AM on July 17, 2013 [3 favorites]


10 million years is what... .25% of the estimated number of years before our solar system is eaten by the sun as it engulfs everything during its ever expanding life?

Well, yes, although I think it's worth pointing out that the planet will be uninhabitable long before the sun actually swallows it up. Wikipedia, in this delightful "Timeline of the far future", says that in 800 million years all multicellular life will die out as a result of insufficient CO2 for photosynthesis.

I haven't read the underlying paper for that claim -- if anyone wants some beach reading, it's "Causes and timing of future biosphere extinction" (fulltext PDF) -- so I don't know if that takes into account the complete utilization and oxidation of all fossil carbon reserves, as an intelligent species might actually choose to release in order to stave off such a fate, or just atmospheric carbon, or if that's not a significant contributor to a change in the date given the timescale involved.
posted by Kadin2048 at 6:46 AM on July 17, 2013


It's clear how self-replicating, sling-shotting probes can get here, but not how could they stop here. Would we notice them whizzing by at 0.1c?
posted by rlk at 6:51 AM on July 17, 2013


How about this: there are plentiful sentient alien civilizations in the galaxy but for some reason civilizations in later stages of development, in addition to communicating via methods we aren't able to detect, come to regard this sort of self-replicating probe as we would regard an insect infestation; so probes always get eradicated by alien versions of Joe the Exterminator before they get very far. Or perhaps they all just end up imprisoned in cruelty-free probe traps.

Or maybe, as tmnl's comment suggests, any probes advanced sufficiently enough to accomplish this quickly think of more interesting ways to occupy their time and all retire to some sunny corner of the galaxy to sip piña coladas on the beach and do the sentient probe equivalent of wiling away their time playing shuffleboard.
posted by XMLicious at 6:54 AM on July 17, 2013


Aliens don't like Popeye either

Am I dreaming it, but I remember as a kid that I read a Popeye annual that had him and Wimpy defeating a bunch of talking alien rocks. One scene had them apologising to every rock they tripped over in case it was sentient.
posted by arcticseal at 7:00 AM on July 17, 2013


According to E. O. Wilson, we have yet to discover the majority of species of life on our own planet. We have not penetrated the surface of this planet beyond a handful of miles, and the oceans are full of things we've yet to discover. If there's one thing that is bigger than our ignorance, it's our vanity. We're not "intelligent" life, we're a bit of a cosmic joke, violent talking monkeys that kill and destroy for pleasure. As Bill Hicks proclaimed, "we're a virus with shoes". A truly advanced, intelligent species would want precious little to do with us. We're barely out of caves, bowing to invisible deities, destroying each other over the shades of our skin, do I really need to spell this out?
posted by dbiedny at 7:02 AM on July 17, 2013 [1 favorite]


A truly advanced, intelligent species would want precious little to do with us.

But again, that's putting a really specifically human value system onto aliens. We don't bat an eye when other animals kill each other, why should aliens be disgusted when we do it? Kinda self-involved to think they'd care at all, isn't it?
posted by showbiz_liz at 7:22 AM on July 17, 2013 [2 favorites]


If you've ever watched live television coverage of major outdoor sporting events, you've seen the stereotypical shot from above the the stadium where tens of thousands of camera flashes are going off in the space of a few seconds.

The entire history of human existence is one of those camera flashes. It seems probable that there have been tens of thousands of civilizations that have existed in the 13 billion years of our universe's existence.

It also seems probable that each of those civilizations came into being, thrived, and then went extinct, unnoticed by the rest of the universe and never to be seen again.

Just like a single camera flash in a stadium of 70,000 people.
posted by DWRoelands at 7:27 AM on July 17, 2013 [3 favorites]


Any ship that can approximate the speed of light would essentially be a planet destroying missile. I think that if there are intergalactic aliens, they probably have something on the order of NATO for FTL/Near Light Speed craft, and don't want anyone coming up with bright ideas too early.

If we even accidentally got access to FTL technology, it would be something akin to a honey badger getting access to a hydrogen bomb.

Also, why explore outerspace when you can turn your solar system in to a matrioshka brain and explore innerspace instead? Much safer, much more interesting, as you are no longer bound by the laws of physics in a simulation.
posted by Freen at 7:28 AM on July 17, 2013 [1 favorite]


I have no trouble believing that intelligent life exists somewhere else in the universe. I'm more or less certain of it. One assumes some of it is advanced far beyond us, and some of it is fairly below us - currently in whatever is its equivalent of an Iron Age or what have you - and some of it is engaged in things that we would not be able to define in terms of our technology, whatever that might be.

It seems like the most likely culprit for their absence is distance. Distance and math.

Specifically, that for any extraterrestrial intelligence to contact us:

Of all the planets in existence, theirs would have to meet the conditions to support life.
Of all the planets that meet the conditions to support life, theirs would have to have life on it, through whatever particular process that happens (it's hard to say because we've only seen it happen once).
Of all the planets with life on them, theirs would have to have had time for intelligent life to have evolved.
Of all the planets with intelligent life, theirs would have to have intelligent life that is advanced enough to observe the universe outside their own planet.
This next is one of what I feel to be the two biggest hurdles: Of all the planets with intelligent life that is advanced enough to observe the outside universe, theirs would have to be close enough to us that evidence of our existence will be visible to them. I think that's huge. I don't know how visible we were from space before the advent of electricity (contrary to popular belief, the Great Wall of China is not visible from space). If we go with "not very," then we're limited to civilizations which exist within about a hundred fifty light years of us. NASA estimates that within 100 light-years there are about 14,600 stars. Within 150, who knows. The point here is that it's a big, big universe but we are only detectable to a tiny piece of it. So they'd have to meet all the above qualifications, AND be close enough to detect us, AND happen to do so.
And the second big hurdle: Of all the planets with intelligent life which can detect us and are close enough to do so, theirs would also have to be able to communicate with us in some way. For all we know, they're sending messages all the time, as we've done to other planets, and we're just not receiving them, or vice-versa. And for all we know, they're getting our messages in binary and just have no idea what the hell to make of them. Maybe they got the Arecibo message and it's their own version of the Wow! Signal, except maybe they penned in, "What the shit is this?" and they're waiting for something else to reach them, watching the skies to see if something comes in that will help them make sense of it. Maybe, to some civilization out there, we are the originators of the What The Shit Is This? Signal.

I think they're out there, and there's every reason to think they're looking for us the way we're looking for them, but at the moment, the distances involved are too great for us to reach them with our current level of technology. In time, who knows?
posted by FAMOUS MONSTER at 7:28 AM on July 17, 2013 [1 favorite]


To add to the possible reasons for non-contact listed by Bora Hora Gobuchul:

6. Any civilization out there that developed the capacity to contact us, by whatever means, would think long and hard about the ethics of doing so. Here on Earth, the government of India has wisely decided no longer to pursue or permit any contacts with the people of North Sentinel Island, about whom virtually nothing is known, who have repelled all overtures, and who are one of the last essentially uncontacted tribes in the world. Besides the obvious wishes of the Sentinelese not to be contacted (which doesn't, yet, have a parallel at the planetary level), there is the ethical concern that attempts at contact could have a variety of devastating impacts on the islanders and would probably wipe out whatever civilization they have maintained there. Consider this situation at the level of Exoplaneteers contacting Earth. If they did so, our civilization would never be the same. Radically disruptive ideas and technologies might be introduced. Any civilization wishing to find us would be doing so primarily for the purpose of studying us, not for the purpose of contacting us to shoot the breeze. So clearly, they would study us unobservably, because showing themselves would mess up the subject of their study. They've got plenty of time. They may have been watching us for thousands of years, who knows?
posted by beagle at 7:35 AM on July 17, 2013 [1 favorite]


"Paradox" is a bit of an overstatement, isn't it? Maybe "Fermi problem" was already taken up by the how many piano tuners in New York type of question.

Well, we could combine the Fermi Paradox with the Fermi Problem and ask: "How many piano tuners in the UNIVERSE?"
posted by crazy_yeti at 7:47 AM on July 17, 2013 [2 favorites]


"What's one more meaningless act of violence on that zoo of a planet?
It would be appropriate.
When in Rome; burn it."

- State of the Art, Iain M Banks
posted by fight or flight at 8:09 AM on July 17, 2013 [2 favorites]


I keep wondering why anyone (or any group) would go to the trouble of designing, building and sending out these viral probes in the first place.

How would the information gathered be returned to mission control?

What's the point of an incomplete catalog of out-dated information about mostly deserts, ice caps, craters and magnetic fields found in solar systems that were hundreds, thousands, tens of thousands of LY away and have moved and changed since the measurements were taken? Especially given the fact that the closer (and therefore more potentially useful) planets could be surveyed from home without viral probes.

I know we frequently criticize ourselves for short-term profit-seeking to the exclusion of longer range thinking . . . but what's the ROI on a scheme like this, even over the longest term?
posted by General Tonic at 8:36 AM on July 17, 2013


Knowledge is the ROI, General Tonic.
posted by Mister_A at 8:45 AM on July 17, 2013


the question of whether they exist is moot.

Indeed; we are mooting it now.

Who's to say that intelligent life hasn't arisen elsewhere and then long since died out? We're not just alone - we're last.

That's unlikely. Sol is a third generation star: its first forebearers . . . burned too brightly and briefly to sustain the development of life. Second-generation stars . . . have a greater chance of being the center of a civilization, and third-generation stars like our own greater still. . . . The Universe has an awful lot of time left to give before the last fires go out.


what if we're first?

Maybe there's no one to make contact with yet, because we are all alone, for now.

Maybe we're supposed to become the Elders of the Universe.

Maybe it's our job to build the universal wormhole superhighway, found the League of Self-Aware Intelligences, seed the stars, leave monoliths on likely planets, help junior civilizations avoid our mistakes, become a race of immortal serene bastards, etc.
 
posted by Herodios at 8:53 AM on July 17, 2013 [7 favorites]


It's extremely unlikely but part of me wonders if Sliding Spring is actually one of these. I guess if it were we would have started to see it braking by now, but I guess I still hold (a very tiny bit of) hope?
posted by thecaddy at 9:01 AM on July 17, 2013


Maybe they got the Arecibo message and it's their own version of the Wow! Signal, except maybe they penned in, "What the shit is this?" and they're waiting for something else to reach them, watching the skies to see if something comes in that will help them make sense of it. Maybe, to some civilization out there, we are the originators of the What The Shit Is This? Signal.

The "Wow!" signal was detected in only 1977. The Arecibo message was transmitted in 1974. Pioneer 10 was launched in 1972. We've barely inaugurated a proper effort to say "hello, universe" or listen to it.

But we can't invoke the Fermi Paradox without factoring in the Great Filter. We simply don't know how many hurdles intelligent life has to clear before it can achieve interstellar communication and exploration, much less which are the hardest ones to surmount. Maybe the biggest one is behind us, maybe ahead. For all we know, the reason intelligent life across the galaxy hasn't apparently been able to visit is that when the stars are right the Great Old Ones descend and usher in planetary extinction events.
posted by Doktor Zed at 9:07 AM on July 17, 2013


I love the idea of dolphins calling US fish.

Or dolphin nerds correcting others, "No they're not fish, they're mammals like us!"

And then the nerdolphins get beat up.

One of my favorite Douglas Adams passages:
"Man has always assumed that he was more intelligent than dolphins because he had achieved so much...the wheel, New York, wars and so on...while all the dolphins had ever done was muck about in the water having a good time. But conversely, the dolphins had always believed that they were far more intelligent than man...for precisely the same reason."
posted by Celsius1414 at 9:19 AM on July 17, 2013 [3 favorites]


There's also the idea put forward by Greg Benford et al that the universe is most suited for machine intelligences, and machine intelligences may wish to root out and exterminate biological life.
posted by KokuRyu at 9:22 AM on July 17, 2013


Conspiracy theories time:

FTL travel, by its wonky nature, causes things to travel back in time.

At some point in the distant future, humanity sends Von Neumann machines to discover aliens/seed life in the greater galaxy. However, they are propelled back into time to a point early in the universe's existence, when life has only barely started to develop on other planets. These machines accidentally disturb this process, killing the native life or terraforming over them, creating bountiful pine forests and savannah populated by non-sentient Earth creatures.

Not only were we the alien malignant terraformers all along, we killed off all of the aliens, but once our non-FTL generation ships get to those planets, they will be struck by religious fervor and disbelief at Terran biomes appearing for no apparent reason. Their descendants will be so impressed by these discoveries that they will create Von Neumann machines life-seeders that travel FTL, and etc.

Someone resurrect Asimov with science so he can write this half-baked plot that I just came up with.
posted by Apocryphon at 9:22 AM on July 17, 2013 [2 favorites]


I just hope they're picking up some early jazz radio broadcasts and smiling to themselves. Someday. Someday.

I'm having no luck finding it, but on one of the umpteen 'interesting people talk about about stuff' programmes I half-listened to on Radio 4 or the World Service this week, a bloke from the SETI project was leading a discussion about first contact with aliens and mentioned that the first radio broadcasts with enough oomph to make much headway into space were... Hitler's speeches.

SETI bloke joked that, assuming aliens recognise the radio signals for what they were and had the tech to translate, the first ones to land on earth will probably greet us with a jolly 'Guten tag!'. Which rather glossed over the horrifying idea of aliens' first encounter with us lot being the hootings of deranged Nazi, I thought.
posted by jack_mo at 9:37 AM on July 17, 2013


Maybe we're supposed to become the Elders of the Universe.

I really love that thought.
posted by forgetful snow at 9:45 AM on July 17, 2013


Hmmmm... would any species risk a smart, out-of-control, self-relicating matter outbreak? What a blight that would be to an aspiring species.
posted by Slackermagee at 9:45 AM on July 17, 2013


on Radio 4 or the World Service this week, a bloke from the SETI project . . . mentioned that the first radio broadcasts with enough oomph to make much headway into space were... Hitler's speeches. SETI bloke joked that . . . the first ones to land on earth will probably greet us with a jolly 'Guten tag!'. Which rather glossed over the horrifying idea of aliens' first encounter with us lot being the hootings of deranged Nazi, I thought.


Was this revelation before or after Contact (1985) (or Contact (1997))?
 
posted by Herodios at 9:48 AM on July 17, 2013


"At any practical pace of interstellar travel, the galaxy can be completely colonized in a few tens of millions of years. . . . Where is everybody?"

So many unexplored assumptions there.
 
posted by Herodios at 9:50 AM on July 17, 2013


For all we know, the reason intelligent life across the galaxy hasn't apparently been able to visit is that when the stars are right the Great Old Ones descend and usher in planetary extinction events.

Which is why I'd really like to see various agencies and collectives working on reactions, as solutions would seem a tad optimistic, for various possible types of Outside Context Problems.

Also would like to see the species stop spinning its bloody wheels and get a move on into the next age. From the industrial age to the information age, from the information age to the... post-scarcity age (with system wide resourcing)? To the age of some-amazing-invention-that-lets-us-interact-with-the-universe-in-ways-beyond-that-capable-of-our-lying-eyes?
posted by Slackermagee at 9:50 AM on July 17, 2013


Why would they bother?

What do we have that they would want?

Art, someone to hold, a cat, the latest sport results?
posted by ersatz at 10:13 AM on July 17, 2013 [2 favorites]


There are no aliens. No-one is coming. There is just us. Let's try to do a good job.
posted by Potomac Avenue at 10:35 AM on July 17, 2013 [1 favorite]


Was this revelation before or after Contact (1985) (or Contact (1997))?

Hah! Seems the man from SETI was making a reference to the novel/film that I completely failed to get. I should probably try actually listening to the radio rather than having it burbling in the background.
posted by jack_mo at 10:38 AM on July 17, 2013 [1 favorite]


It will be interesting to see if humans can hang on at a technologicaly advanced level for another 500-1000 years. If we develop the ability to travel and considerable fraction of c, I think The Orion Arm will end teeming with islotated human populations in a dozen or so millenia.
posted by spaltavian at 10:40 AM on July 17, 2013 [1 favorite]


There are several comments about alien self-replicating automata finding that they have better things to do than go explore. That's fine and all, but all it takes is *one* self-replicating machine to start seeding the entire Galaxy. (Think of the Earth three billion years ago, with all these protein molecules hanging around and lounging in the primordial soup - and then this one left-handed molecule decides to go ahead and self-replicate and ruin it for everyone...)

One of the better responses is that self-replicating automata are considered pests and infestations, and sophisticated civilizations actively exterminate any that happen to be passing by.

Or maybe the wildlife sanctuary idea is the best - we're living in a zoo and don't know it yet.

Or maybe there is a dark slab waiting for us on the far side of the moon, or one of the Earth-crossing asteroids has suspiciously regular dimensions.

Or maybe we really are the first. If so, we're working our way up the chain. We know of 700+ confirmed exoplanets, with a few thousand more candidates. We are beginning to detect colors for these exoplanets (HD189733b is blue!) and we're working on techniques to image them directly. In a few decades, if we're still up for it, who's to say we won't launch a thousand-year mission to visit one of them?
posted by RedOrGreen at 10:50 AM on July 17, 2013


From the paper:

Our model for probe replication is a very simple one. While a probe is travelling between stars, we assume it collects matter from the interstellar medium, and this is used to create a replica probe. We assume that the quantity of material collected during the flight is great enough such that the probe does not have to stop and mine for materials at any time ...

Those are some very generous assumptions. I guess you could tweak the model a little so that the first probe carries an excess of certain rare materials that it could pass along, but it seems that the probe is still going to have to serve as the equivalent of numerous factories and refineries.
posted by exogenous at 10:59 AM on July 17, 2013


They are just watching to see what we do with our capabilities, how we put together the puzzle pieces we have, and they won't reveal themselves until we've shown we're clever and resourceful enough. Those obvious-in-hindsight milestones like the light bulb, the computer, electricity, where all the component ideas were right there but few noticed. Right now they're pretty skeptical because, despite having all the pieces in place and staring us right in the face, we haven't produced an epic mashup track titled "Rappers Deee-Lite". It's oversights like that which really call into question our abilities as a species.
posted by jason_steakums at 11:06 AM on July 17, 2013


FauxScot: "We're deluded if we think we're any better than yeast in the eyes of stellar visitors."

That's an unfair comparison. Yeast makes beer. Humans also make beer but then they drink it themselves.

Yeast wins.
posted by Hairy Lobster at 11:21 AM on July 17, 2013 [1 favorite]


showbiz_liz: "Take octopuses. There is mounting evidence that they are really, really fucking smart. But I say 'mounting evidence' because, although we can observe their behavior, we can't communicate with them nor they with us, and their desires are so totally incomprehensible to our mindsets that even if we COULD communicate, we might not have any common reference points that would make understanding possible. We don't even have all of our senses in common."

Add to that the following fact (and I'm only half-joking at best):

Despite realizing just how smart these creatures might be we still continue to eat them.
posted by Hairy Lobster at 11:26 AM on July 17, 2013 [2 favorites]


The first sign of intelligent life will be when we can finally perform detailed spetroscopy on the atmospheres of transiting exoplanets. First, we will detect a reactive component that can only be explained by biological processes, like oxygen. The real paydirt will come when we detect the presence of devastating industrial pollution.
posted by [expletive deleted] at 11:31 AM on July 17, 2013 [2 favorites]


Despite realizing just how smart these creatures might be we still continue to eat them.

Once the oceans have finally been exhausted and are of no more use to us, it will dawn on us that the only true sea monsters that ever existed didn't lie beneath the waves. They roamed the surface, dragging behind them their cavernous detached mouths and countless metal teeth.
posted by [expletive deleted] at 11:38 AM on July 17, 2013


Whoa, [expletive deleted] -- are you saying the monsters is us?!?!?!?!?!
posted by Mister_A at 11:48 AM on July 17, 2013 [3 favorites]


Personally, I like Michio Kaku's take on this whole thing. In a nutshell, our not finding alien life he attributes to several factors already mentioned in this thread, condensed in what at least feels like a realistic explanation:
Although we have not detected aliens, they may have detected us. Why then don’t they make an effort to communicate? Perhaps they are not interested in us. Michio Kaku uses the analogy of human contact with ants. When we come upon an anthill, he explains, we do not request to see their leader or bring trinkets to them and offer unparalleled prosperity through the fruits of our technology. Because of astronomical time scales, a civilization capable of visiting Earth could be many millions of years ahead of us and thus might find us uninteresting. Moreover, it would be unlikely that any such advanced civilization would find any resources on Earth that could not be found in numerous other star systems closer to their civilization. As Kaku points out, the main danger ants would face is not that humans want to invade them or eradicate them. Rather, we might simply “pave them over because they are in the way.” In this scenario, the danger would be if Earth got in the way of the aliens’ highway.
posted by Marisa Stole the Precious Thing at 11:49 AM on July 17, 2013 [1 favorite]


A Von Neumann machine capable of making copies of itself from whatever it can find in a solar system would most likely require strong AI.

I'd just like to observe here that we are Von Neumann machines capable of making copies of ourselves from whatever we can find in the solar system. If your civilization can build a Von Neumann machine with strong AI and send it out to replicate across the galaxy, well, congratulations: you've just created the aliens you were hoping to meet.
posted by Mars Saxman at 12:30 PM on July 17, 2013 [2 favorites]


we are Von Neumann machines capable of making copies of ourselves from whatever we can find in the solar system

No, no we can't. We're actually really fragile and specific in our needs.
posted by Dark Messiah at 12:50 PM on July 17, 2013 [1 favorite]


> "The first sign of intelligent life will be when we can finally perform detailed spetroscopy on the atmospheres of transiting exoplanets."

"When we can"? We're already doing this.
posted by kyrademon at 1:19 PM on July 17, 2013


No, no we can't. We're actually really fragile and specific in our needs.

Correct. You can't rustle up some chocolate cake and a blackjack game in just any old part of the universe.
posted by forgetful snow at 2:05 PM on July 17, 2013


Well you ain't hangin' 'round the right corners o' the universe then.
posted by Mister_A at 2:12 PM on July 17, 2013 [1 favorite]


My simple theory: We haven't communicated with aliens because if we had, we'd be dead.

I would pity any species stupid enough to attack Earth. Pity and kill.
posted by IvoShandor at 2:33 PM on July 17, 2013 [1 favorite]


No, no we can't. We're actually really fragile and specific in our needs.

Yes, yes we can! It is what we do - it is the purpose of our global industrial economy! We find useful raw materials, apply energy, and convert them into other useful materials, ad infinitum, until we have assembled appropriate feedstock inputs for the intelligent self-replicating machines we call "human beings".

But whatever. I agree that Homo sapiens is likely to prove an expensive and ineffective design for our hypothetical self-replicating interstellar probe. I'm just pointing out that this notion of a machine which can move to a new environment, identify and extract its own feedstocks, assemble a new instance of itself, and send the next generation along on its way is actually a very familiar one; this is the process we call "life". You could say "Alien-built self-replicating Von Neumann style space probes", or you could just say "aliens"; it's the same thing.

I remember an SF trope from my childhood which played with the idea that aliens might have non-carbon-based biochemistries - silicon was the most common suggestion. This has come to seem unlikely, but likely we will continue to develop ever-more-sophisticated silicon-based robots, and perhaps some day we will build intelligent, self-replicating silicon-based robot life forms and send them adventuring out in the galaxy on our behalf. Perhaps they will meet other silicon-based alien robots, and they'll assemble a vast, slow-moving galactic alien robot civilization which has little to do with any of its squishy biological progenitors, trapped in their fragile gravity-well-bound ecologies.
posted by Mars Saxman at 3:21 PM on July 17, 2013


Maybe we're supposed to become the Elders of the Universe.

Ahem. Wrong epithet.
posted by Apocryphon at 4:21 PM on July 17, 2013


In this scenario, the danger would be if Earth got in the way of the aliens’ highway.

Is this a nod to the Hitchhiker's Guide to the Galaxy? Or did Douglas Adams steal this idea from him?
posted by marble at 6:48 PM on July 17, 2013


> Is this a nod to the Hitchhiker's Guide to the Galaxy? Or did Douglas Adams steal this idea from him?

I wouldn't be too surprised if they came up with the image separately, but H2G2 was broadcast three decades before Michio Kaku's book (which that quote was pulled from), so I assumed it was a wink and a nudge.
posted by lucidium at 7:32 PM on July 17, 2013


I'm doubtful the project could get funded given the galactic fiscal and political climate. I mean the duration is more than ten million years, most of the work is to be done by machines, resulting in few net jobs and the first results from the explorer its won't be received for a very long time. Not to mention that the proposed self replicating, autonomous machines do not exist and may be beyond the technical limits of materials science and engineering.
posted by humanfont at 7:49 PM on July 17, 2013 [1 favorite]


Obviously they have shown up. (Like people show up in Wall, SD.) Then they have a look. Then they say "Remember when we were like that?" Then they have a good laugh and warp out after leaving a bunch of ultraviolet "thumbs-down" votes on the other side of the Moon.
posted by Twang at 8:39 PM on July 17, 2013


Don't we have, like, pretty bad sky coverage despite all of our telescopes, radio telescopes, etc? I seem to recall that being a thing. So they may not even need to be hiding, they could stumble through the solar system pretty blatantly and we'd run a huge chance of missing them.
posted by jason_steakums at 8:53 PM on July 17, 2013


The Best We Can - "First contact was supposed to change the course of human history. But it turns out, you still have to go to work the next morning."
posted by the man of twists and turns at 9:15 PM on July 17, 2013 [2 favorites]


ZaphodB: Who's to say that intelligent life hasn't arisen elsewhere and then long since died out? We're not just alone - we're last.
That's... pretty much part and parcel of the Fermi Paradox. Please read the sections beginning at "It is the nature of intelligent life to destroy itself" in the first link at the beginning of this thread.
posted by IAmBroom at 2:18 PM on July 18, 2013


Hairy Lobster: FauxScot: "We're deluded if we think we're any better than yeast in the eyes of stellar visitors."

That's an unfair comparison. Yeast makes beer. Humans also make beer but then they drink it themselves.

Yeast wins.
You and I have vastly different definitions of "win".
posted by IAmBroom at 2:23 PM on July 18, 2013


exogenous: From the paper:

Our model for probe replication is a very simple one. While a probe is travelling between stars, we assume it collects matter from the interstellar medium, and this is used to create a replica probe. We assume that the quantity of material collected during the flight is great enough such that the probe does not have to stop and mine for materials at any time ...

Those are some very generous assumptions. I guess you could tweak the model a little so that the first probe carries an excess of certain rare materials that it could pass along, but it seems that the probe is still going to have to serve as the equivalent of numerous factories and refineries.
You mean, it would have to do as much work as the simplest known archeon? OK.
posted by IAmBroom at 2:31 PM on July 18, 2013


Let me know when you have a single-celled organism able to survive and replicate during interstellar travel while possessing advanced sensors and communications ability.
posted by exogenous at 4:43 PM on July 18, 2013


Hey, I'm just the ideas guy. I'm Jobs. Somebody else has to be Wozniak. I can't do everything.
posted by IAmBroom at 10:20 AM on July 19, 2013


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