Was There Someone Here Before Us? And Unusual Technosignatures with Jason Wright

you have fallen into event horizon with John Michael Gautier [Music] [Applause] [Music] in today's episode John is joined by Professor Jason Wright Jason Wright is a professor of astronomy in astrophysics at Penn State and a member of the Center for exoplanets and habitable worlds he studies stars their atmospheres their activity in their planets whilst also working on SETI he is the project scientists for need a pipe of the Nexus for exoplanet system science a COPI eye of the miniature exoplanet radial velocity array and a member of the habitable zone planet finder team you can learn more about his research on his blog there's a link in the description or by following him on Twitter at Astro underscore write Jason Wright welcome back to the program thanks again know Jason we were just talking off air about some of the weird incidences that happened around the KSC eight four six two eight five two affair that one team actually our two teams apparently actually looked at it in laser and found something and one ended up being an errant cosmic array and the other I'm not sure what happened he telling them yeah when's a B star became a sensation and everybody was interested in it for the SETI angle it naturally got targeted by all the city programs because you know that's how I became famous is that we tried to use the Green Bank telescope to see if there are any radio signals coming from it so there are two projects to find laser signals that might come from stars that work in different ways one is based at UC Berkeley through the breakthrough listen project and they're looking for continuous-wave laser so someone's shining a laser all the time and it turns out you know it doesn't take that much energy to outshine a star if you use a laser and you're only concerned about our shining the star that one wavelength that one color and so that's what they look for is is that and they looked at lots of targets they looked at to have you star of course and then when they went to go publish their results and see if they had anything interesting they wanted to publish their very best candidate as an example of what they were looking for and wouldn't you know at the very best candidate they had was tabby star in this case it turned out that what they had found was a cosmic ray so this is a misnomer it's uh it means an energetic particle the product of radioactive decay and so basically our detectors are so sensitive that even the trace amounts of uranium let's say in the walls of these observatories will occasionally give off a particle and that particle will hit the CCD and you'll detect it and it'll be really bright and it'll be really obvious and it'll often look like a laser mine and so we call these things cosmic rays because they're there's similar properties to the energetic particles called cosmic rays that come from space even though they're actually coming from the walls there's kind of a joke in astronomy that if you see something really weird that may doesn't make any sense you just ascribe it to cosmic rays so cosmic ray hit the detector or maybe a cosmic ray went into my computer and it messed up the calculation and that's why that thing didn't work and you run it again and it never happens again the running gag something weird happens something goes bump in the night doesn't make sense never happens again cosmic ray now speaking of uranium in the walls uranium uranium in a star we have a candidate techno signature and it is a ship Bilski star which seems to show some very very strange elements within it including apparently uranium and upwards supporting one study if that is indeed there is this the closest we have come to saying that that could be due to an alien civilizations activities yeah so pebble ski stars one of my favorite Astrophysical enigmas it's just so neat it belongs to a very strange class of star at least we think it does it's really anomalous where it's very slowly rotating and they're very strong magnetic fields and apparently this combination of the temperature of the star and the strong magnetic fields causes the different elements in the atmosphere to segregate and form layers so all of the let's say I don't know we'll pick something like nickel or something in the atmosphere of the star we'll get concentrated at one layer and if that layer is deep enough that you can't see the layer then you won't see any nickel in the star at all whereas another element in the star like I don't know I molybdenum or something like that might I'll concentrate much higher in the atmosphere where you can see it and then you'll see an amazing amount of molybdenum like much more than you should ever have any right to see in any star because we've got all of the atmospheres we lived at them right there where you can see it in that fin layer these are called chemically peculiar stars AP stars and they really have strange abundance patterns but seville ski star is just totally off the charts it has so many spectral signatures of so many elements so many transitions of so many elements that we actually have a very hard time identifying any of them and this is because the heavier elements on the periodic table have lots of different ways that their electrons can can transition they provide many different wavelengths of light where they can absorb so if you put enough of this stuff enough of these heavy elements in the way all those lines will overlap and it's just a complete mess and you can't identify anything sort of I guess like you know trying to pick out you know one piece of music when many many pieces of music are playing if you just have enough of them there's just too many and you can't tell them apart so people have heroically tried to identify these lines one problem is that we don't actually know at exactly what wavelengths a lot of the heavier elements absorb just because no one cares enough to go measure very carefully but the the one study that tried the hardest at this and really did their best to identify the lines concluded that they had confident detections of transionic elements of actinides and this should not be possible because the elements they were discovering have half-lives of like a hundred years or in some cases just you know less than a year and such elements can't exist in nature because they decay away far too quickly and so it's impossible it has to be a line misidentification which it's not surprising because we can't identify any of the line so it's clearly just a mistake but there does exist the possibility that you know maybe it's technologically generated so you know why would there be technologically generated short-lived radioisotopes in this star the the original idea how a proposal for this goes back as far as I can tell to Carl Sagan and shklovsky who oh and I'm sorry it goes back to Skowronski and Drake I think who apparently made the suggestion that if you wanted to let people know you were out there you could put something you know like plutonium in a star or technetium in a star and then anyone who noticed it there would know you it had to have been put there they call this salting Stars and so that could be a really interesting beacon and very energy-efficient too you just have to put the material in there and then the star has it and it'll shine and everyone will be able to detect it for you know as long as the stars are out so it could be a beacon the the second idea is that it might be a repository for fissile waste so this was a suggestion of the times made around 1980 when disposal of fissile waste was a real problem I mean it's still a real problem but when it was a really salient problem on a lot of people's minds it's gone away for some reason that you know you could just get rid of it by dumping it onto the Sun or something like that now that that's an absolutely terrible idea you should you know the last thing we should be doing with our nuclear waste is putting it on gigantic towers of rocket fuel and lighting them it's just it's far too dangerous who knows maybe someone's doing that dumping a lot of fissile waste into the star it seems a little far-fetched to me but the suggestions out there so it's entertaining to think about now what of technetium with this star i don't know if it exhibits technician I think actually technician is observed in space I'm not this isn't really my field but I think it is actually produced in supernova I guess and so sometimes you do see it perhaps but you don't you don't find it on earth because it's all decayed away in the five billion years that Earth has come along but like I said with this star it's hard to identify anything the elements they identify are all transuranic Slyke um actinium and einsteinium these things pretty hard elements to arrive at now astrophysically say that stuff that is actually in there is there is there a special circumstance where it could be being produced in on a continuous basis say bombardment or a Tron star something like that there was a paper that suggested that if there were a nearby neutron star you could somehow do the the the chemical nuclear reactions necessary to generate the problem is there's no neutron star around it I mean it's a clever idea but this star doesn't have any companions those those lines that we see they're always at the same frequency we see them just constantly at the same frequency so that means there's no Doppler shift no changing Doppler shift which means nothing's orbiting the star we know that to you know very high precision so there's no neutron star actually my favorite my favorite suggestion which is really clever is that they are the decay products the daughter products of a reservoir of some other elements that is more slowly decaying so the idea is that there is some stable element out in an island of stability the physicists call it that we've never synthesized that we've never made elements heavy enough to notice that they're stable for who knows thousands millions of years it's possible most calculations say all of the elements up there are extremely unstable but some suggest that there might be silent of stability so if for whatever reason this star has a lot of that element and we don't have any of it on earth so it's unclear why they'd have it but we don't but okay let's just say a special supernova enriched it or something then this element might be in the atmosphere stratified as these this class of star does and slowly decaying and that could be the reservoir that's generating all of these daughter decay products all the way down is it as it decays down to uranium or something like that I really like that idea because it means that in principle if you can confirm these elements are real and if you can confirm or really there and you can confirm that they appear in the appropriate quantities to be a decay chain that you would have detected or at least inferred the existence of a new chemical element in space and I'm pretty sure the last and only time that's ever happened was with helium and it would be the first new element in nature in a long time so that would be pretty cool well presumably an entire group of all the way up to this island of stability you would have you know above stuff that we've synthesized so far anyway no that's true I mean we know that they can't exist but yes you would have discovered them that's right you will have discovered them and maybe you could tell from the lines in the spectrum which ones they were and actually do some spectroscopy of them that would be pretty cool I like that idea it's it's a really obscure idea but it's a lot of fun to think about it is and it's interesting because I mean I don't know that these elements that they've synthesized were recently must go VM and all those that they even last long enough to get a spectra off of it exactly I mean even yeah that's right and so we wouldn't even know you'd have to presumably do the quantum mechanical calculation to figure out what the energy levels are and I'm not I'm not a quantum chemist so I don't I don't know how hard that is but my understanding is it's very hard and maybe beyond our capabilities right now yeah I I tend to think so just synthesizing them was hard enough and wondering about what kind of what kind of chemistry could go on with such an element it's just all speculative no other techno signatures another one comes to mind the red spiral he has an overview of that I'm not sure it's a techno signature but it's a really neat little story there's a website called Zooniverse where citizen scientists can go and help astronomers with gigantic data sets that are just too big for them to to work with and one of the projects was called galaxy zoom and so the idea was that there were these large all-sky surveys that just took images of the entire sky and they wanted to do old-school galaxies morphological classification where he's okay that's a spiral galaxy that's an elliptical galaxy and you know that's a lenticular galaxy that's not a galaxy that's two galaxies and it's very hard to get a computer to be able to do that without a training set you have to give it an enormous set where you say all of these are this all of these are that all of these are that now go do the rest and so that's what Galaxy Zoo was for is that all these volunteers learned about the kinds of galaxies and then categorize just thousands and thousands and thousands of these things was extremely productive and useful scientific endeavor but one of the cool things they found was a rare class of galaxies that was not in any of the classification schemes and that are the red spirals so the two basic kinds of galaxies are elliptical galaxies in spiral galaxies and spiral galaxies you know they look like pinwheels like the Milky Way or in dromeda or m51 or something like that and they've got the great spiral arms and all along those spiral arms are bright blue stars and that's because the spiral arms are sites of star formation and when you form a lot of stars at once some of them have very high mass high mass stars are extremely bright they outshine all of the others even though they're pretty rare and they're very blue because they're very hot and so it's characteristic of a spiral galaxy to have all these blue stars and then elliptical galaxies generally have very little dust and star formation going on they're often the products of spiral galaxies that have merged and just burnt up all of their dust and gases as stars and are done forming stars and so they don't they haven't had any stars form in the last say hundreds of millions or billions of years and as a result they don't have any blue stars oh they have very very few blue stars and for different reasons and so they are dominated by the light of the red giant stars which are stars maybe like the Sun that have been around for ten billion years and are now red giants so the general rule is that elliptical galaxies are red spiral galaxies are blue and what the galaxies ooh people found were red spirals they looked like spiral galaxies but they didn't have any blue stars and that's really strange and so the red spirals as they came to be known emerged out of that project and they're an interesting anomaly the way it's usually explained is that in the past they had a huge burst of star formation and that all of the stars from that burst the blue ones are all gone they went supernova but the lower mass stars are now red giants and so the idea is that they do still have star formation they still do have blue stars they just have an unusually large number of red giants and that's why they appear red and you know that makes sense I think what you mean by techno signature is that they're ideas that if you're a galaxy spanning civilization and you have ambitions to last a very long time in the galaxy and minimize supernova explosions or worse that might you know caused a lot of trouble that you would somehow suppress high-mass star formation and prevent those blue stars from ever forming in your galaxy and so this galactic engineering essentially to make it safe for the species that fills it and so that might look like a red spiral and so I think that's what you mean that they the red spirals could actually be a technical signature so it in that regard so if you're looking at galaxies and you see a galaxy that is very reddened and has a whole lot of excess infrared as though it's full of Dyson spheres then you might be getting into territory where you can say that is unambiguous right no I wouldn't say unambiguous if if if I saw and you'd be very interesting right it would satisfy the the it would look a lot like proposed techno signatures where as you say maybe lots of Dyson spheres maybe suppress the blue stars that might be what it looked like but it would also be consistent with something that had a burst of star formation in the past that's why it's red and is and still has a lot of dust and maybe has a lot of star formation also right now maybe it just had a merger so that would also give you a lot of of excess heat what you'd want to do is look very carefully at the morphology of the galaxy and just see where the infrared emission is coming from if it's coming from the spiral arms and the sights of star formation well that's all it is it's no big deal but if it's coming from all of the stars in the whole galaxy if it's not clumpy the way that dust is that would be very suspicious so it would be it would be anomalous to see infrared excess in a red spiral and in fact we looked for that we in the G hat survey we checked all of the red spirals just to see if any of them had infrared excesses and indeed a very small number of them had too much infrared radiation which was pretty strange and then we wanted to check to see if maybe there are some reasons why that might happen involving ultraviolet light or them being a John and we checked that and and those didn't pan out either and so we think those four or five galaxies were identified must have some very strange star formation histories to be read and have infrared excesses and have the ultraviolet flux that they do so we did flag those as interesting anomalies that kind of fit what we were looking for there distant and hard to study and like I say there's a good natural light well there's there are reasonable families of natural explanations for them so no I don't think it's unambiguous now what about a distance to those galaxies because eventually you're you're looking out so far that there just wouldn't have been time for a civilization to form up in that galaxy from your perspective seeing oh yeah these aren't that far away these aren't a cosmological distances and so they the light we're seeing left those galaxies when the universe was not very much younger than it is today now other techno signatures I think the most weirdest one I've heard of lately as Roger Penrose saying well maybe you could send a message buy it from a previous universe by encoding it in the cosmic background radiation do you think we should take that step is that a step too far I yeah I'm out of field here Roger is a brilliant guy with a lot of amazing ideas III guess I would say that there are a lot of a lot of things that have to go right for that for that prediction to pan out there have to be other universes they have to be connected in some way that that you can send information from one to the other I'm not even sure what that would be involved but also I mean if that information is let's say encoded in the cosmic microwave background there's not much information there like you know the whole cosmic microwave background map is just it's not that much information so I don't I don't know how complex such a message could be and still be decodable yeah I'm not gonna argue with Roger but I'm not sure how that would work now out of all of the techno signatures that you are aware of potential techno signatures what's your favorite what's the one that that really fires your imagination the most mmm fires my imagination the most hmm well I like I like infrared excess waste heat looking for the inevitable heat that comes from technologies use of energy because it could be anything it requires the least imagination or supposition about what it is they are doing so I like I like that I also am partial to that because that's what I look for because that's closest to my wheelhouse as an astronomer I'm not a radio astronomer I don't build hardware I don't work with fast electronics and things like that and so that's the one that I can most easily look for and so that's the one that that that I work on but that's not to say I think it's the most likely one to pan out I really don't know what which techno signature will be the most obvious now could it be something you know we look at you know short terms with techno signatures you either see the Dyson Sphere you don't but there also some that are much more long term so say you're looking at exoplanets and you're doing several centuries of study of earth-like exoplanets and all of a sudden you see are actually let's frame it like this aliens are looking at us and all of a sudden Mars becomes habitable yeah terraformers now is that I mean is that perhaps a more viable way of detecting an alien civilization no I don't think I mean findings I mean to terraform a planet would take a very long time and if it didn't take a very long time you're unlikely to see it happen I mean this is the L in the Drake Equation that if you want to detect something your probability of detecting it or the number of them that there are to detect is proportional to how long the Tecla signature lasts so if you want to see something change over the course of ten years like go from uninhabitable to habitable or something like that then you're looking for something that took ten years of you know the age of the universe and so it's very unlikely that you would just have happened to catch that planet at the moment something like that happened people have also proposed for instance looking for you know the evidence of I don't know interplanetary warfare or a planet destroying itself like praxis or something like that but again those are very brief they if something only takes a short while to happen it must be happening all the time or you're very unlikely to have caught it however things like terraforming are definitely the kind of thing that you might infer technology for if you have some reason to suspect that a planet has been terraformed so people have suggested looking for habitable planets outside of the habitable zone like you know how is it that that planet still has that atmosphere at that distance from the star that shouldn't be possible perhaps there's some geoengineering going on or let's say you have three planets in the habitable zone of some of some of some star and all of them have identical atmospheric signatures three planets different sizes different distances from the star identical atmospheres that would also suggest terraforming right because you would not expect three totally different planets as different installations to end up in the same way so I think that's a cool idea for a techno signature yeah and one that I mean we're getting pretty close to being able to look for that now with James Webb going up and all that yeah I hope so it's going to be very hard it's going to be very very hard to study to restaurant atmospheres even with James Webb yeah I hope it works we're gonna be limited to close you know I mean maybe we can look at Proxima B or something but yeah characterizing atmospheres is only just barely now you know something that we can start to talk about but once we do I mean if you saw like you said three planets with the same atmospheres and if it got really interesting and two of those planets had CFCs because that's a excellent greenhouse yes yeah so you could terraform a world with it and then you're outside of ambiguity at that point which you know ambiguities always been the plague of Seti so well no I don't think I big you to spend the play I mean radio and lasers said he does not struggle with ambiguity you mean it can if they go looking for four things other than the the sort of canonical narrowband radio signal or the the laser the pulsed laser you know they might go looking for more ambiguous techno signatures but you know if you see a narrowband radio signal from space and you confirm it with another instrument you're done you win there's no ambiguity you've discovered life elsewhere in the universe but I hear what you're saying unless it fails to repeat because we picked up such a signal well that's why I said if you confirm it you've got a it's got to be confirmable you have to be able to know that it wasn't a cosmic ray which is the maddening thing about the WoW signal is it definitely wasn't the cosmic ray well I don't know what the WoW signal was yeah I mean it would be and again this kind of goes back to our rate arguments if things like the WoW signal were common then someone would have seen something like it at some point since then but it still remains this singular event more powerful and stranger than anything we've seen if it really was alien signal from space then we were extremely fortunate to catch it because it's apparently not a very common phenomenon and yeah it's also frustrating because if it never repeats then then there's no way to know that it wasn't just a cosmic ray or something like that now that said Bob Graves pointed out that if the WoW source is is repeating all the time we would barely know it because we don't know exactly where that telescope was pointed I mean we know where it was pointed but it was a big beam so we don't know exactly where on the sky it came from and that region of the sky has not been thoroughly searched at those wavelengths for very long he estimates that we've probably spent something like 24 hours of total integration time staring at that part of the sky that entire part of the sky look and sensitive at those wavelengths and so it could be for all we know blinking at us once every 24 hours and we still wouldn't know well he would be the one that looked at it for most of those 24 hours I would imagine yes that's how he knows the number yes so say we we we get to this point where we find a techno signature then we get to have the debate on should we beam a mess - what's your take on MIDI okay so these are two different questions so one question is once we detect something should we try to get its attention the other is should we be broadcasting deliberately now in an attempt to elicit a response to see if anything's out there and that's what I think we normally think of in terms of MIDI I don't think we should because I don't think it's likely to work I know most people say I don't think we should because I'm worried it will work and they're gonna come eat us or something like that my opinion is that these broadcasts are far too weak they're far too transient to matter I mean imagine if there were a civilization out there trying to get our attention and they you know blast it in our general direction for an hour unless we just happened during that hour to have a radio telescope pointed at the right frequency at that source during that one hour out of what five billion years or something like that it's not gonna make any difference we're not going we're not going to catch it it needs to be something sustained for an extremely long time before it's going to work against someone's attention I think things like the Arecibo message are valuable because they remind us how sensitive we are to radio signals at interstellar distances it gets us thinking about our place in the universe it gets us thinking about SETI because it's thinking about what would happen if we were to make a contact but I don't think they're useful because they have any chance of actually giving paying attention I sort of like the Arecibo signal for another reason because if in thousands of years it propagates out someone sees it it's going to be there while signal I do enjoy that symmetry that's really nice that's when you confuse the aliens rather than contact them now just switch gears you wrote another paper that fascinates me because of the implication of it is that if you did detect some kind of an alien artifact or something like that a solar system you may not be able to prove that it's even alien exactly rare indigenous technological civilizations give us an overview of that paper yeah prior indigenous technological species yeah a few years ago my mind was blown when and I don't even remember how the idea came but it was it was I know that one of the the seeds was was thinking about Gavin Schmidt and Adam Frank's work asking about whether we could rule out a prior technological species on the earth and so whimsically you would say how do we know the dinosaurs didn't have cellphones we know and you think oh well that silly we'd see it in the fossil record but no the fossil record is extraordinarily incomplete I mean out of you know millions or billions of dinosaurs that walked the earth you know we have fossils of a few we really don't know what what was around then only certain things get fossilized so they wouldn't they they were thinking about them prophesying this idea that the the humanity's impact on earth is now so indelible and so significant that it is it's worthy of a geological strata man a name and so there are these eons and epochs in earth's history where where things changed and the rock is you know you can see it in the rock layers something was different then and they're there the argument of the Anthropocene is that we've already done so much work and we will continue to do so much work to alter the geological layer that we're putting down that geologists a hundred million years from now going down through the rocks we'll be able to say look that's where it started and and tell that we were here and Frank and Schmidt don't dispute that they said it's true but given enough time it won't obviously be technological like something was different then but you'd be hard-pressed to prove that it was technologically different there are other things that might have been able to do it and it's surprising how much of our technology will vanish and just not be around and certainly not be recognizably technological in just a hundred thousand years and they argued that after a million or two years there'd be no way to know technological at all and so in fact if the dinosaurs had cellphones we would not know it because you know we wouldn't see the cell phones and all of the other stuff they did would just be another layer that we would misinterpret so building on that um I was thinking well you know this could be true everywhere that that if we we go and we we look at Mars and it seems dead but we forget how recently it was just understood that Mars had life had cities and canals and all of that stuff I mean a hundred years ago there were respectable scientists who thought Mars probably had life and even intelligent life and we got the pictures from the Mariner probes back and it was just desert and there was nothing there and somehow the needles swung all the way to the other side from probably or maybe has life to definitely never had life in its entire history and there was no evidence for that we've never had evidence that lets us go back just what's on the surface of Mars today in terms of life or even technological life and so I started thinking you know maybe Mars did have cities it wouldn't take that much time for them to be gone maybe Venus had cities and then the the global greenhouse effects has just completely wiped them out and they're gone maybe Earth has had many technological species in the past and so if that's true than if we as you say find an artifact in the solar system the usual idea is that that must have been deposited here by some visitor from interstellar space but given that Earth has life and it's right there isn't it more likely that earth life put it there at some previous spacefaring phase of of its history and I don't know if that's more likely but it's interesting I think that that is somehow to most people seems like a ridiculous idea even though we have no evidence for it one way or another I think that's interesting because Venus that would be an extreme example of this because number one I planet apparently had liquid water for a very very long time up until geologically speaking relatively recently for it went all crazy but the thing is that planet also is even worse than Earth it apparently cracks open and resurfaces and it completely resurfaces it so which would completely eradicate any evidence of anything ever having been there that's right if if Venus has had a resurfacing and I'm not sure it's certain that it has but I know that that is a common interpretation of its geology that's right then all evidence of everything that was there is completely gone it's been totally folded into the mantle and yeah you'll never know anything about it now with Earth of course I mean people don't really realize just how active this planet is and destroying its surface it will grind in overtime entire continents underneath a plate and you know basically melt it down so the vast majority of the history is you say this this planet the fossil record is just not there I think it's it's I think it's actually mostly life and erosion but yeah your point is well-taken I mean there are the the plates that subduct under the under the oceans and stuff we do have rocks that are billions of years old and a lot of the earth's surface is billions of years old but I think people also as you say they don't realize how quickly life just destroys everything on its surface like if we all vanished how long would it take before our our technology was you know not visible anywhere it's not very long I mean if you do special things like build a gigantic pyramid of rock in the middle of a desert that'll last thousands of years but almost anywhere else it's gonna go away pretty quickly and yes certainly over over geological timescales where you know earthquakes and eventually subduction for some parts of the earth yeah it'll just go away so deep time is really really deep and what seems very permanent now is not on a geological time scale I agree now what have Mars say this might have happened hypothetical yeah yeah on Mars it probably would last longer wouldn't it I mean so you have a piece of giant piece of rebar concrete when it gets buried on Mars 50 million years ago this is still gonna be there in that and yeah I don't know the answer to that question but I would guess that if you have rebar on Mars that that some biological entity made to the rebar which means you've got life like you have life energy of a biosphere and I think that the biosphere would destroy the rebar pretty quickly yeah the rebar definitely the concrete though I'm not so sure yeah or the concrete um um I mean it's just silicate so if it buried yeah I don't know yeah I don't know enough about it I mean if it's on the surface it'll get sandblasted on on current Mars but that also means it'll get buried in so I don't know how long concrete lasts yeah it's a good question it could it also I guess conceivably there's there's a case of of a quarry I think in Sweden where they found what appears to be fossilized meteorites where the traces of the meteorite remained in the sediment like iridium and things like that but but most of the silicates are gone and it's been replaced so one more if that could happen with a with an artifact you know yeah I'm sure I mean I mean you think about lichens right and all they need is sunlight in a rock and they'll you know give them enough time and they'll just eat the rock through the long time although with rocks I suspect erosion is faster yeah wouldn't surprise me if bacteria are also an important player so I guess that's the paradox that if you've got the technology and it's indigenous technology then the indigenous life if it's anything like earth life is not gonna let it last for very long so the main thing is if it were deposited there if it were like a remote base or something like that like Elon Musk wants to build on Mars or something like that you know if we set something like that up maybe like the Antarctic station that we have how long does it last and yeah the sands gonna get it pretty quick but then it'll get buried and after it gets buried you don't have any you don't have much in the way of Mars quakes you're not gonna you're not gonna have Santa get any more maybe you got to worry about meteorite impacts I don't know yeah I mean or asteroid impacts mmm-hmm if you live long enough in a star system you're eventually going to get hit you know unless you do something about it that's right now what implications does this have on on searching for extraterrestrial life because if you had a prior technological civilization on here or Mars or Venus and they left and decided oh we're gonna go out to the Oort cloud because we can compute more efficiently because it's colder or something like that then even if you got evidence an artifact of them or something like that you could never say that they were actually alien because it's just earth life and even if they were genetically very different well maybe they have full command of their genetics and customized it so you can never actually say at a certain distance that something is unequivocally alien that's true you can't prove a separate Genesis you can't prove a separate abiogenesis event just from that artifact I mean some people would go farther though and say that even if we find definitively extraterrestrial life maybe that radio signal from a distant star well you know maybe the origin of life on Earth is common to the life that was on that star maybe maybe that was earth life that went over there or maybe the prime a hypothesis is valid and someone seeded both places so yeah the separate origins is always going to be a puzzle unless unless they know the answer and they tell us but that seems that seems far-fetched to me but maybe but then you have to trust death they could be just telling feeding us a line this is actually one of the reasons I I'm more actually interested in microbial life in the yappers because there you don't really have that kind of possibility of subterfuge it's either related to us or it's not you know so yeah oh you mean if you find it in the solar system then you can check yes if you find it at Europa and you look at the genetics and you're like there is just no commonality at all then you can say okay there the universe teems with life you know I would not be surprised if in a couple thousand years the humans on Europa managed to stock the subterranean ocean with all sorts of genetically modified fish that can live in Europa and it could be a completely synthetic life-form that's they've designed to be there I mean we're already talking about generating synthetic life here on earth and so yeah give us thousands of years and I bet we'll have lots of synthetic life that has no lineage with any other life on Earth and perhaps we'll build it exactly because it thrives in space so I don't know and maybe they'll even exhibit conversion evolution artificially so it looks like a shark so you have try an artificial your open space shark that's right and we turns out it and we made it which is now again this is this goes back to the thing that that's better than aliens if we can do something like that that's more interesting than an alien civilization yeah which honestly I I do wonder in regards to bio signatures if if we don't really have a better chance of understanding abiogenesis actually from a test tube in other words the alien life comes out of a test tube well from the you know the biologists looking into the origins of life which seems like that's probably gonna happen within our lifetime so even if we don't find a bio signature or techno signature if it looks like the chemistry of abiogenesis is easy then we can still look out there and say yep it's everywhere at least microbial life yeah it's possible my personal suspicion and this is an uninformed suspicion is that abiogenesis is hard it might be very common it might have happened in the blink of a geological eye on early Earth that's possible but the blink of a geological I might mean a million years of a lot of things going just right and it's possible that there's no substitute for just waiting that these reactions are extremely unlikely that you need just the right foam bubbles on a tidepool this and that and that there's no way to hurry it up and simplify it and do it in the lab it's possible that that you know will will always just be wondering well this is probably how it happened we think I don't know well the one thing the one interesting thing about that though is that however it happened it seemed to happen just as soon as it was possible in this world you know it that is consistent with evidence but I've heard it persuasively argued that that it's not that ironclad that the the dates on those rocks and the evidence for life in those rocks which is isotopic it's not even in the rocks it's in these little minerals in the rocks a particular isotopic ratios that are consistent with life you know I think it's an ambiguous bio signature and so it's certainly possible like I said that life arose as soon as we had water on the surface but it's also possible you know this is hard that we've over interpreted that evidence and it actually took let's say I don't know that it took 100 million years I don't know the numbers I'm not a geologist but that it was actually on the long side and if that's the case then maybe it was a rare rare event on earth but you know the universe does not like uniqueness so there are probably other examples no we're not you we're not unique that's true life is not unique to Earth I'm pretty I am pretty I think I can confidently say that now what do you think about civilizations though do you think your gut feeling our civilization is relatively common or is intelligence just a very very rare and that it explains the Fermi paradox well the question is what's the hard step it's possible that Earth had many hard steps from abiogenesis to you know cells to multicellular life and then from multicellular life to life with they can be social or can use tools I think Earth has had many examples of intelligent tool using species and social species right we as far as we know are the only one that is social and tool using and language using and has all of the the things that we do that that give us so much technology but we have plenty of examples of very intelligent species here on earth today you know octopuses and dolphins plenty of social species plenty of tool-using species so I kind of I'm kind of surprised given that that we're the very first to figure out technology and I bet there have been species did that that found technology maybe even found you know fire and and and built things I mean beavers build dams and stuff but beyond just instinct but really solving problems in developing new technologies I'd be surprised if we were the first on earth I would not be surprised if we're the first to do geoengineering and build big cities and rockets that it seems right that we are the first to have done that but again we don't actually have evidence so that's it for me if if if life multicellular life with with neurological capabilities like like animals is common then I think technological species are common so I think we're either gonna find you know we're not gonna find lots of forest moons and things like that and not find technology I think with at least some of them now my last question for you relates to yet another paper what is the aurora effect the aurora effect yes so this was Adam Frank's idea based on a novel by Kim Stanley Robinson the aurora effect is that not every habitable planet is is habitable wait oh shoot I can't remember how he phrases it but it's based on a novel where humans go to a planet and it seems like a great place to live but it turns out that because of the stuff already living there it's not you can't live there you can't also be there and maybe the aliens from War of the Worlds discovered that about our that looked like a great place to be but it turned out that they just couldn't live here so the reason this came up in this paper is that we wanted to understand how severe the the Fermi paradox is specifically Fermi's original articulation which has nothing to do with SETI asking why aliens aren't here in the solar system today weren't obviously here in the solar system today and the argument is just a crossing time argument that even with today's technology we can create spacecraft that given enough time can get to nearby stars and even cross the galaxy now enough time means hundreds of thousands or millions or tens of millions of years but that's fine those timescales are short compared to the age of the galaxy so there's been time if there have been other technological species for them to have populated and settle the entire galaxy if they were so inclined so the question is why haven't they or if they have why don't we notice them here here in the solar system so one one piece of the puzzle in the paper was well how do we know they haven't what's our evidence horizon and so based on his work with Gavin Schmidt they said all right let's be generous and say 10 million years that if if they were here in the last 10 million years we would have noticed so then the question is well how often do they visit so we ran some models of how long it would take to visit all the stars in the in the galaxy and we don't know how often they would launch ships or how fast their ships or anything like that so we just parameterised it all and said well if the ships are typically this fast if this many this fraction of stars are the sorts of places that they could settle and launch new ships from and we tuned those parameters and just saw under what circumstances you would expect a star like the Sun to have been visited in the past 10 million years and under which circumstances 10 million years is a perfectly reasonable time to go without being visited and so that helped us put constraints on on you know how ubiquitous space travel must be among technological species in the Milky Way and do you expect it is ubiquitous because I mean space travel is also very hard it's not very hard uh I mean we do it it took us I mean I mean I'm serious like I mean from the development of flight to the first interstellar probes was decades just a few decades so I don't think it's it's hard in that sense it's hard in the sense that I think the hardest part of the problem of going to nearby stars is building something that will last long enough to get there the Rockets aren't the hard part the hard part is how do you build something that very far from a star will still be going and useful in 100,000 years and that we don't we don't understand we do not understand how to build machines that last anything like that amount of time so it would presumably have to be something that can repair itself perhaps you know it's a colony ship and it's people that are doing the repairing I don't know but that's the hard part but it also doesn't feel so hard that we'll never do it on a cosmic timescale to me I mean we already can outline we can draw the outlines of how such a thing would work you know hollow out an asteroid use its mass for propellant off you go so the fact that we can outline and describe it and it doesn't violate any laws of physics to build a slow ship suggests to me that it's it's actually not that hard if we could basically do it well and you can also reframe it because if you build say hollowing out an asteroid and you build a gigantic generational ship eventually that can you can be so extensive that it is a world so rise you space travel you're just going about life on a world more or less that's right exactly right if it's spinning you've got your gravity and if it's big enough it's got enough propellant to go you know kind of fast the the asteroid gives you plenty of shielding from everything on the outside you've got all the raw materials you need to keep it going I guess I don't know how you do fusion or fission or something for your energy and that's right if it's a generation ship then it's its own world but the other thing is by the time it arrives they're no longer really earthlings right I mean they're they would be our genetic descendants but a hundred thousand years of your own culture with earth just ever getting ever farther away you can communicate with and try to maintain that culture so you know as long as stuff on earth is still transmitting you can still receive an answer and interact but when you're that disconnected you know you're gonna be your own thing by the time you get there so I guess they're earthlings biologically but um but culturally they'll just be doing their own thing when they finally get there yeah they would might not even know that they were from being in this world all right yeah yeah I mean earth would only be a couple light years away so you know they could still call phone home as long as there was someone to answer well if you've got enough of these things he it goes sort of like the von Neumann probe where you know no exactly colonize the entire that's what we found in a simulation right I mean once they're there how long until they launch another one and you're like oh well you know why would they do that well I don't know you know give him a hundred thousand years someone's gonna do it yeah and so that was one of the parameters in our in our simulation was how long does it take them to launch another one and we were pretty conservative we decided they'd only do it every a hundred thousand years or something like that and that's still plenty to effectively create as you say of annoying the Machine this self-replicating series of settlements that quickly takes over the whole galaxy all right Jason we are out of time it's been a fantastic interview and I think I think the thing that I'm worried about most is if if aliens that are colonizing the galaxy in the far future come here and they see Europa and they say that looks exactly like the place we want to colonize except the humans have infested it with artificial space sharks yeah and they move on maybe the Europa report was about their ship it was great talking to you Jason I hope you come back all right thanks for having me John why is the car back I thought we'd pass that story out what the barians in the driveway well don't quite hmm Baron hmm it's missing a knee wait the whole cars been altered this technology is far build human capabilities an alien civilization upgraded to lebaron can I translate that he said that his space probe encountered it and it wants a new carburetor why I guess I could call Randy it's got a forcefield little Barrens become a techno signature it's consuming the driveway for raw materials abundant Bevin probe [Music]

Channel: Event Horizon

Views: 601,663

Rating: 4.7765656 out of 5

Keywords: fermi paradox, enrico fermi (academic), physics (field of study), aliens, ufo, space, alien, planet, science, documentary, universe, extraterrestrial, life in the universe, asmr, john michael godier event horizon, event horizon, Alien Artifacts, solar system, NASA, self-replicating spacecraft, technological, civilization, europa, Venus, mars, intelligent life, red spiral galaxies, galaxy, technosignature, jason wright, Was there someone here before us? And Unusual Technosignatures

Id: lh0skjMpJHo

Length: 54min 5sec (3245 seconds)

Published: Thu Jul 16 2020

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[u/johnorso]

Checking this out.

[u/rubbleTelescope]

Event horizon channel is great to listen to from time to time.

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