Astronomy / Space The Fermi Paradox — Where Are All The Aliens?

I quite like the idea that we could become the Type 3 civilisation that goes around ensuring that none of the other civilisations in the universe get too successful.
 
In a few more decades, when we travel beyond our own system, we will discover the ancient hyperspace relays and the cycle repeats itself ;)
 
The thing, though, is that all info is reaching us at the speed of light, which is pretty old info when you are looking for signs of life in other galaxies, let alone our own.

If another intelligent species outside the Milkyway had equipment that managed to pinpoint Earth and look at us directly, they would see a planet in early development. Depending on how far away they are, they might see dinosaurs, or no sign of life at all. Or no planet even.
Andromeda is the closest galaxy, 2.2 million LY away. They would see the earliest stages of man.

It's still pretty tiny in comparison to the age of the Universe though. Even if a Galaxy is 100 million LY distant, the Universe is 13.2 billion years old. So in the case of Andromeda they still had 13.18 billion years.

There are ~2,500 large (Milky Way sized) galaxies within 100 million light years and another 50,000 dwarf galaxies. That's a lot of stars...
 
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The thing, though, is that all info is reaching us at the speed of light, which is pretty old info when you are looking for signs of life in other galaxies, let alone our own.

If another intelligent species outside the Milkyway had equipment that managed to pinpoint Earth and look at us directly, they would see a planet in early development. Depending on how far away they are, they might see dinosaurs, or no sign of life at all. Or no planet even.
Andromeda is the closest galaxy, 2.2 million LY away. They would see the earliest stages of man.

Yes, but again it's all matter of scale and perspective. Galaxies in that research are relatively close to us: few million of light years, perhaps up to 50 million light years for some. On the other hand, all of them are ten or more billions of years old: that's awfully lot of time. If one, and one only, civilization managed to start colonisation of their host galaxy, just 100 million years ago, and eventually evolved into type III, their (infrared) footprint would have more than enough time to reach us. In this regard, few million (light) years is minuscule compared to age of the universe and galaxies in it.

In all those countless stars, planets (and years), we need just ONE successful space-faring civilization, just slightly older than ours, and it would be all over the place. Fact that there is none, is strange, disturbing and exciting at the same time.
 
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Since life emerged on this little rock, what makes you think it couldnt emerge on other rocks?

Because there is zero evidence of such a thing.

Do you believe, for example, in the Yeti? There really was a giant ape living in the Himalayas. But the idea that the Yeti still lives there is something any sensible person rejects outright. It's easy to see how the legend of such a creature might get started if ancient people living there had encountered this creature, but today? Nope. Still, that is evidence that such a thing might just be there. A million to one chance, but still evidence, however slight.

In the case of aliens, you have none. Nada, zero, zip. Humans have left the earth and found dust and boulders. Nothing else. It is actually more logical to believe in the Yeti, the Loch Ness Monster, and the still-alive Elvis than it is to believe in aliens.

There have been a few recent break-throughs in this.

One is that the complex molecules needed to form DNA have been found pretty often in the universe. Not just carbon and hydrogen, molecules.

Yes, I've seen this myself. Amino acids and complex compounds which form the building blocks of life. But you know what is absent from these discoveries? Life.

DNA has never been observed to form spontaneously. Never. Until such a thing is observed or demonstrated the origin of life remains a mystery. The most common argument for the existence of alien life is various forms of the highly unscientific Drake Equation, which basically states that "Life must be out there, because space is so big man". But this is actually a problem or alien enthusiasts - the fact that life seemingly exists in one location in such a huge universe speaks volumes about how much of a freak event it is.
 
^^ Yep. I believe that simple, microbial life might be a pretty common thing throughout the universe. Perhaps more complex life forms too. But intelligent life? It does look like a freak accident, as you nicely put it. Something so impossibly rare that the universe must get A LOT more older for this chance to grow a bit higher. Perhaps we are really alone - not only in our galaxy, but the universe as whole. Evolution took 4 billion years to produce sentient beings on Earth: while it does look like an awfuly lot of time, maybe it's not like that at all. Perhaps evolution of intelligent life on Earth in fact happened incredibly fast.

It's going to be interesting once we manage to investigate (assumed) watery ocean hidden beneath the Europa's icy crust, or Titan's methane lakes. If we don't find anything there, nor on the Mars, Venus or within the cloud layers of gas giants, this could mean that even the microbial life is sparse more than we think.
 
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"Simple. I got very bored and depressed, so I went and plugged myself in to its external computer feed. I talked to the computer at great length and explained my view of the Universe to it," said Marvin.
"And what happened?" pressed Ford.
"It committed suicide," said Marvin and stalked off back to the Heart of Gold.
 
First question should be "are we truly sentient ourselves"? Are we really our own masters? And that is yet to be answered. Who knows? There might be some limits. Like urge to self destruction that we might not overcome or at some point we might just stop develop as a species or even start to degrade back to primitive animals! Time will tell.

Now back to aliens. Time and space might be different concepts for different species. We might not even notice each other because life can be so different. We always try to think that everybody else should see things like we do. And it might not be the case. Can we truly notice and understand sentient mold? Bacteria? Virus? Thinking rocks? Does sentient mold need spaceships, cities or advanced technology like we understand it? Or perhaps there's lifeforms that perceive world in different dimensions than us? There might be even some sentient aliens who simply does not care to make contact either. And that would be reasonably cautious move. Who knows what consequences actual contact might bring? Sure there might be some evidence but how we will know for sure that it is what it is and not some random noise? Space is big after all. Too many if's.

Anyway. AI is the closest thing we can get to consider "alien" and IMHO it will happen earlier that we get the chance to meet actual aliens. I just hope we can get to other planets before true AI happens. Who knows what it will decide to do about us? Will it consider itself threatened, decide to be friendly or just ignore us because such concepts will be beyond machine consciousness?

I think it's a irresponsible and foolish that we neglect space exploration and colonization. We can wage wars and decide who rule who _after_ we ensure that we have some chance to survive as a species in the long term. It doesn't make any sense.
 
I just hope we can get to other planets before true AI happens. Who knows what it will decide to do about us? Will it consider itself threatened, decide to be friendly or just ignore us because such concepts will be beyond machine consciousness?

Mu guess is that, at first, AI will be looking at us as Gods. A creator. Then the AI atheists will eventually show up, and that's when we should really think about spreading out to other planets :D
 
How can anyone be sure intelligent life out there does not exist. With our crude technology we wouldn't be able to detect alien communication.
It's like going to the beach, dipping your toe in the water and then claiming the sea is devoid of life simply because you didn't see or feel anything.
 
How can anyone be sure intelligent life out there does not exist. With our crude technology we wouldn't be able to detect alien communication.
It's like going to the beach, dipping your toe in the water and then claiming the sea is devoid of life simply because you didn't see or feel anything.

Our technology isn't crude in this regard. We have developed to the point were we can detect the energy output of a planet. If, for example, an alien civilization were to point a radiotelescope at our own solar system they'd see a bright star and an even brighter planet (Earth) because of our communication systems and media. And that's just radio. There is also microwave, light, etc.

Any technological species will produce energy of one form or another that becomes detectable to any other technological species.
 
If, for example, an alien civilization were to point a radiotelescope at our own solar system they'd see a bright star and an even brighter planet (Earth) because of our communication systems and media.

Space full of waves of all sorts, noises, abnormailities. It isn't the problem to find what you seek. It's distance and concept of time. It's not there in our "here" and it's quite hard to tell if something artificaial or not either. There just so many of everything in space but it's all so far and out of reach! We can't just go there and look it up in most cases and thus majority of what we know in that regard stays as a theory.

P.S.
Just my IMHO, I'm not an expert in any way.

Mu guess is that, at first, AI will be looking at us as Gods. A creator. Then the AI atheists will eventually show up, and that's when we should really think about spreading out to other planets :D

It might. But I think true AI will be different than us. It will be so much different that it can wipe us out but not because of hate. Which it simply might not even grasp as a concept. It can wipe us out as we remove dust from our belongings. We are inefficient after all, at least not as efficient as machine can be. And if it will be true AI - it will need to evolve and adapt to survive. It might not care about our petty struggles and just do what it reqires to survive in the long term. Like stripping whole planet of resources and life, then moving on. Even if machine can achieve sentience and learn to understand what we are - why should it copy us if it's truly sentient and have free will? It is what it is, it's not digital human. It's just we like so much to expect that everything else out there should be like us, to serve our needs and reminds us that we are the pinnacle, that we are in charge. We been doing it our whole life. We learn not to but slowly and after overcoming one false idea (Eppur si muove) we create dozen others :(
 
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^^ good point regarding the AI.

When you come to think about the efficiency and cold AI logic, it becomes even more strange that no one in our galaxy has ever managed to create self-replicating machines (something like Von Neumman's probes) which should be able to spread throughout the galaxy pretty fast, consuming all available resources along the way, until the point when every single planet and asteroid has been strip-mined and all, or majority of stars enveloped with Dyson spheres.

There was enough time for this to happen in the long history of Milky way -let alone other nearby galaxies- but it did not, obviously.
 
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^^ good point regarding the AI.

When you come to think about the efficiency and cold AI logic, it becomes even more strange that no one in our galaxy has ever managed to create self-replicating machines (something like Von Neumman's probes) which should be able to spread throughout the galaxy pretty fast, consuming all available resources along the way, until the point when every single planet and asteroid has been strip-mined and all, or majority of stars enveloped with Dyson spheres.

There was enough time for this to happen in the long history of Milky way -let alone other nearby galaxies- but it did not, obviously.

Machines just might evolve faster and doesn't need Dyson spheres or mine resources after some point. Or they simply might hit the wall in development on the concept scale. Like some paradox or limitation. Who knows how they act when space and time bends? I mean we are mortal thus we can percieve time as we do. They don't die as we are do. Time is different for a machine. They are quite alien in that regard and not sure how endless "outside" of Space can affect them in that regard.
 
Our technology isn't crude in this regard. We have developed to the point were we can detect the energy output of a planet. If, for example, an alien civilization were to point a radiotelescope at our own solar system they'd see a bright star and an even brighter planet (Earth) because of our communication systems and media. And that's just radio. There is also microwave, light, etc.

Any technological species will produce energy of one form or another that becomes detectable to any other technological species.

Fascinating point of view!! Really like a dissenting and educated view on the matter! However, I always thought all the signals we produce are travelling at, well, the speed of light, if that! Being that we truly started doing the radio thing like 60-70 years ago, would those alien hundreds of light years away still be able to see that "bright" planet??? We just sparked ourselves not too long ago! ...but that goes both ways... even if they started 1,000 years ago...they need to be within 1,000 ly for us to pick up the signal!


It's just we like so much to expect that everything else out there should be like us, to serve our needs and reminds us that we are the pinnacle, that we are in charge. We been doing it our whole life. We learn not to but slowly and after overcoming one false idea (Eppur si muove) we create dozen others :(

I agree with our egocentric point of view as species in many points of our history. We are biased as species. However, many brilliant minds are in the search of life out there. And the reason why they are expecting something similar to us, is not this species bias. Is actually way more simple than that: common sense.

Is not like we are not open to find a "silicon based" life form, or a "gas made dna" or any other very and fundamentally different life form than us. We are aware that's a possibility and open to find it. The problem is, being so extremely different, what do we know about their needs and development, much less about the conditions they would need to live? What do they sustain themselves off? what would it be needed for them to develop societies?

Those questions become ten fold hard to explain when we are imagining possibilities of life than can be very diverse and wildly high number of different life forms to then find out and speculate on their needs, development, civilization and technology in the hopes to -without knowing for sure- start looking for signs of such speculations.

The reason why we look for stars and planets similar to Earth and Sol is because this is what WE KNOW it works and we can detect it easier and know exactly what we are looking for. Is not because we think life should be equal or even similar to us. We just don't have any better reference than ourselves at this point.
 
The reason why we look for stars and planets similar to Earth and Sol is because this is what WE KNOW it works and we can detect it easier and know exactly what we are looking for. Is not because we think life should be equal or even similar to us. We just don't have any better reference than ourselves at this point.

Good point. Yet it blinds us.

This is great post from another topic in Off topic forum. I have some small issues with it but otherwise it's rather well worded.

There are plenty of animals on Earth that are sentient. Including Humans, Elephants, Dolphins, Pigs, Octopi, Orangoutans, dogs, etc. We're in the process of wiping them out, but that doesn't make them any less sentient. Animals are quite intelligent, and some of them have pretty good vocabularies. There are border collies that are capable of basic grammatical constructions, indicating advanced logic (i.e: "fetch the blue ball that is on the green box" and the dog will not fetch the blue ball that is on the floor) Octopi have demonstrated the ability to learn by observing other octopi solve problems, which is pretty cool, really - it's a trick many humans have trouble with.

Sentience is sometimes defined in terms of self-awareness, but that definition would mean that many primates are sentient, as well as some other animals. A famous example of self-awareness is the "spot test" - if you paint a white spot on a chimp's forehead and show it its own reflection in a mirror, the chimp will reach up and rub at its forehead. Elephants also do this.

Unfortunately, attempts to define "sentience" often seem to be "trying to come up with a definition that excludes all animals except humans" - so you wind up with some rather bizzare criteria like that sentient creatures must speak with a brooklyn accent. ;) But, seriously - if you look at tool-use, we've known that primates use tools for a very long time, human-centric advocates simply say that those tools aren't tool-y enough (ignoring the tools that early humans made, which are ... basically the same) Eventually you wind up with silly definitions of "sentience" in order to shore up human's superiority.

What many people mean by "sentience" is often "sapience" - the ability to engage in rational thought. I'm not a big fan of that term because I know a lot of humans that aren't sapient, and a few dogs that are.
 
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Our technology isn't crude in this regard. We have developed to the point were we can detect the energy output of a planet. If, for example, an alien civilization were to point a radiotelescope at our own solar system they'd see a bright star and an even brighter planet (Earth) because of our communication systems and media. And that's just radio. There is also microwave, light, etc.

Any technological species will produce energy of one form or another that becomes detectable to any other technological species.

Our current equipment is nowhere near that sensitive. There could be a equivalent (both in terms of age, development and emissions) technological society to ours within 50 light years of our solar system and the chances are that we wouldn't be able to detect it with anything like a degree of certainty unless they were actively attempting to broadcast their presence.
 
Good point. Yet it blinds us.

This is great post from another topic in Off topic forum. I have some small issues with it but otherwise it's rather well worded.


Supposing the scientists at SETI don't know this...what could be done about it? how else should they be looking?

Excellent post by Surly_Badger...one of the sharpest pens in these forums, IMO. And I agree...for all we know the Universe could be teeming with life just like Earth, just not "technologically" advanced (?) like us...
 
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Fascinating point of view!! Really like a dissenting and educated view on the matter! However, I always thought all the signals we produce are travelling at, well, the speed of light, if that! Being that we truly started doing the radio thing like 60-70 years ago, would those alien hundreds of light years away still be able to see that "bright" planet??? We just sparked ourselves not too long ago! ...but that goes both ways... even if they started 1,000 years ago...they need to be within 1,000 ly for us to pick up the signal!

Yes you're right.

The first radio broadcasts, or human broadcasts of any sort, that were capable of interstellar transit were first sent by Germany in 1936. Specifically the Berlin Summer Olympics. This is why that particular event was used in the movie "Contact". That was 79 years ago, so any civilization with radiotelescopes or means of detecting radiowaves within a distance of 79 light years knows that we are here.

If they're over 79 light years away the only way they'll know about us is if they've mastered some sort of faster than light detection/communication/travel, if they're relying on radiowaves alone. There are other ways, for example the increasing atmospheric carbon content from the industrial revolution could easily tip off an alien race to the presence of a species burning hydrocarbons to release energy, if they were monitoring earth over a period of years.

BUT!

Our galaxy is ten billion years old. It would only take one single star out there somewhere to develop life in the system. Our local star is running out of fuel. We're very late to the great big space party. If life sprang up anywhere in the galaxy during the first half of its lifetime we'd have detected something by now, if they had technology, even if that civilization was deep inside the milky way.

There is the possibility that civilizations go extinct very quickly due to the fact that with superior intelligence comes godlike stupidity (we are arguing about global warming while our planet dies around us for example).

And there is also this.

https://en.wikipedia.org/wiki/Wow!_signal

Our current equipment is nowhere near that sensitive. There could be a equivalent (both in terms of age, development and emissions) technological society to ours within 50 light years of our solar system and the chances are that we wouldn't be able to detect it with anything like a degree of certainty unless they were actively attempting to broadcast their presence.

To detect and decipher a signal yes, but to merely detect? No it's pretty easily done at this point.

Radiowaves are basically lightwaves on a wavelength human eyes can't see. They're produced by stars and other sources as well as human activity, but radiotelescopes can see those wavelengths quite easily. If a rocky planet was producing way more radiowaves across the entire radio spectrum than, for example, a nearby star that would be a massive anomaly which would indicate a high probability of technology on that planet.
 
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Supposing the scientists at SETI doesn't know this...what could be done about it? how else should they be looking?

Excellent post by Surly_Badger...one of the sharpest pens in these forums, IMO. And I agree...for all we know the Universe could be teeming with life just like Earth, just not "technologically" advanced (?) like us...

I'm a proud wearer of tinfoil hat (well, baseball cap but it sure magical and block mind reading :p). I don't think that SETI is a right thing to do in the first place because... it might be bogus effort, curtain for a bloated botnet that have nothing to do with aliens or space. May be I'm wrong and being overly pessimistic.

What scientist in general should search for? Everything worth noting, everything that expand our knowledge and understanding. But sentient life far away? Even if we can somehow confirm the fact - we have no means to meet and exchange information. No means to confirm in person. It's too far in space and time. If we learn to bend time though... Then it might get interesting! Because I do believe that time is actually quite different from what we think it is. If black holes can manipulate it, if vast emptiness can alter it's flow... It's not something constant then to begin with. At least in some extreme conditions it can change. It will still require fast ways of travel but without conquering time fast space travel doesn't solve much because as far as we know space is endless and expanding. But I'd rather have fast space travel... any space travel than not having it :)
 
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