Star Talk Chat Room – A Deep Dive Into the Cosmos, with Neil deGrasse Tyson – Week 4

welcome to Startalk chat room this is a deep dive into the cosmos and we're featuring episodes 7 & 8 from cosmos possible worlds and later we'll be joined by planetary scientist Carolyn Porco to talk about Cassini at Saturn but right now let's get into episode 7 titled the search for intelligent life on Earth so this this this episode opens with a shot of the current world's largest Observatory it's 500 meters in diameter it's called it's called the fat Chuck hey Chuck hey how's it going see this is Startalk in the corona verse that's right you do this well how did you it's called the fast telescope which is a brilliant acronym so it's 500 meter aperture spherical telescope and it's in China and we'll tell you more about it in just a minute but to get images for it it's so large you can't just take a handheld camera and photograph it so we had these drones that just ascended right up the middle of it and then the whole telescope comes into view it's so large it's a mile in circumference Wow yeah it's just it's just crazy that is mind-blowing yeah and it's large because for several reasons radio waves themselves are large and it's a radio wave telescope so radio waves can be anywhere from a few centimeters small radio waves right in fact they're micro waves that's weeks yes there you go short end of radio waves are called micro waves and then just got longer and longer and longer so this telescope can receive radio waves from the universe and then focus them so you have to be big just to receive big waves but also radio waves don't carry much energy so you want as much of a collecting area as possible to get as much of that signal whatever it is and wherever it's coming from in the universe so that you can take it decode it and figure out what the hell's going on and what's interesting about radio waves is they passed through obscuring dust and gas in the galaxy uh-huh so many the pre pictures you see from Hubble they're beautiful because parts of it are blocking views from behind or they're glowing red or green or yellow or blue and so it's very beautiful but it's obscuring your your vistas to the rest of the universe radio waves passed right through that so radio waves pass through these obscuring these things that would otherwise obscure our view of the gallic of the universe exactly so if you're aliens and they have technologies such as we and they're smart such as we or at least we define ourselves as being smart then they would figure out as we have that radio waves would be ideal modes of communication across the galaxy with what would be other alien life right because you don't want it stopping in some gas cloud what does that right-waist so unless unless there's a life-form that lives in the gas cloud yeah but okay so then you wouldn't need radio waves you can use some other form light just together let's stop at them in the gas cloud and so so other bands of light just don't have this ability to penetrate the clouds the way radio waves do so radio waves become a very efficient means of sending signals and receiving signals if you're going to search for extraterrestrial life now that when you look at our SETI array of all these you know dishes setting so the search for extraterrestrial intelligence right yes so as is it most likely that if we receive communication that it will indeed be through radio waves I'm just saying if they want to talk across the galaxy that's the best way to do it unless they figured out yet here's what it's a little scary you know we only discovered radio waves you know hundred twenty years ago hundred three hundred Hertz and a few others in the late 19th century so if you if if someone sent signals to earth during the Roman Empire way there's still what we would call intelligence on earth but have no clue that someone was trying to Yap at them from across the galaxy so imagine that there's some other means of communicating we have yet to discover that's even better than anything we've invented but the aliens have figured that out Wow they could be yapping at us right now and Olivia's it's funny because it's what you say makes so much sense in that I'm just picturing an ancient Roman with a radio right now just twist in the DAO going there is nothing on this thing I mean yeah well it's right so so who are we to say that radio waves is the be-all and end-all of how you would communicate through the galaxy I could have come up with something as advanced compared to our radio waves as radio waves are compared to Romans just screaming at each other across the countryside so could you so radio waves I mean are they superior or just different than light or different spectrums of light that's a great question so we know the rainbow red orange yellow green blue indigo violet ROYGBIV if you want a way to remember that and we used to think that's just everything and that's it that and then you find out know there's like infrared on the other side and you keep going and you keep making the wavelengths a little longer you get to infrared then you get to microwaves you get to radio waves how about on the other side with the violet you can make wavelength shorter go from violet to ultraviolet and then you go to x-rays and then gamma rays these are the words we have to describe the entire electromagnetic spectrum all of it is quote radiation of different wavelengths radiation has gotten a bad rap in in common carlins we think of it as whatever is bad for you right I get that I understand that but speaking physically about this all of these waves are some form of radiation and only some varieties of it are damaging to you so x-rays you know you don't want to be around x-rays too much not too much okay you know I figured this out when I was a kid right I'd be there in the dentist right and they're ready to take an x-ray and what does the x-ray technician do just before they take x-ray they leave the room beep sir it's like oh you're totally safe I'm just gonna go over here what so why is this okay thing all right I remember thinking this when I was like 9 years old why is she behind a blast shield if I'm getting zapped I remembered thinking that all right so yeah x-rays in low dose or can be very beneficial to diagnosing your health and your your your particularly if you have you know broken bones gamma rays have other consequences they get in and start messing with your DNA okay who's the most famous gamma ray the Hulk the Hulk of course yeah so so we have evidence from DC Comics that excessive gamma exposure turns you into the Hulk but only when you get angry only when you get mad right exactly and honestly seriously he just needed a therapist bro you got anger issues you got anger issues bro he needs a therapist all right and we can work this thing out you know what my another favorite there's a meme out there called the credible Hulk have you ever seen that no but that sounds great Incredible Hulk if you don't want me to be angry you don't like it you won't like it when I'm angry because if you don't give me proper evidence peer-reviewed research angry I like that [Laughter] so any out so there you have it and so this Chinese telescope we used to have the largest in the world in utter SIBO Puerto Rico and that was the largest like four decades meant for 50 years that was the largest telescope in the world and so now the single largest is in China so Chuck let's get to my interview with Jason Clark one of the executive producers of cosmos possible world he became a good friend he was executive producer from 2014 as well as a spacetime Odyssey he has some interesting films in his portfolio by the way he did Stuart Little really yeah and he did I was the one with the talking dog mr. Peabody yeah so he's uh he's it's got quite the only inviting yeah so he I so I asked him what was his favorite scene in all of cosmos and guess where that took us there's a great scene one of my favorites I would say is when you go to China - world's largest radio telescope yeah and it's I don't remember but I think it's a half a kilometer across what's a mile in circumference yeah a good way for Americans to think about is he was largest in the world and and the previous largest one which was in a merc yeah I used to have a baby we don't have the biggest one what are we go yes they're at Arecibo Puerto Rico that is so what it means is if there's a alien message in the din of cosmic noise the most powerful telescopes in the world may pick it up if they do it'll be the Chinese telescope first oh wow the first scientist they will encounter will be Chinese so have there ever been these moments where you've actually believed maybe that's a real signal I'm not authorized to oh that's it turn off the cameras no but that but that scene was a that was in an attempt to convey to the viewer here we are either listening for signals or maybe even sending signals for intelligent life yet there's stuff going on underfoot yeah some of them backyard so this planet which is you know what's most people take for granted it's what we've grown up on its while we've known but at the same time there's so much going on in a way that we're not aware of whether that's you know bees and how they live the bee story that's another edible story the disease we you know you're a busy bee usually means you're busy doing nothing you just move you just you know move an air around and there they are and I learned a lot too I'm an astrophysicist but I don't carry expertise in every topic that I discussed that was scripted and reviewed by other scientists yeah where it's their expertise yeah so that's another sort of unique aspect of this the the scientific intersection that again the EP would look over that right yeah so we you know you know each episode we sent the script to a series of experts that we had hired and each episode was picked apart because not only do you want this kind of what's the new thought and idea but you want one that's been proven or vetted scientifically enough that it's worth repeating right because some ideas are are so early in their discovery that they haven't gone through them well an important element that and persistently introduces which enables the storytelling at the level that it is is we will distinguish between established science and science that's just on the edge yeah and so if it is this then this could be true so we're very honest yet scripturally honest yes literally Scriptures the scriptures are honest script Tuohy honest about the science that is speculative versus the science that's established yeah I find that to be you know there's there's so much detail it's very rich this season and there's so many stories and going back to the radio telescope the idea that the natural world that surrounds us has so many stories that have yet to been told to be told that may teach us about how life could exist elsewhere oh wow man so that first of all fascinating stuff and more importantly what the hell is up with America okay what is going on alright seriously seriously what is up okay the whole point of the episode was to use that as an excuse to say here we might be using telescopes such as this to send signals to potential aliens or vice-versa to receive them but when in fact we have evidence of intelligence on earth that we've overlooked for not only centuries but millennia and so right there in episode 7 we introduced to you perhaps for the first time the intelligence of bees sweet now you know there's no pun intended now you know there be lovers out there who think of bees as producers of honey and of course the vegans don't eat the honey right and so bees honestly vegans it's bee vomit you can't come on seriously you can't bring yourself to eat the bee vomit it's not like you're hurting the bees no you're missing the opportunity a bee bars just to beep yeah beep are there you go bee barf it's like come on I got it I got a feeling the bees are feeling just a little superior every time we eat a little honey there's just like can you believe those humans scarf scarfing down our barf scarfing our barfing really so I first person I heard call addy barf was David brennick the comedian oh that's right Philadelphia comic David Brenner yeah yeah he I turned say that I think what he's hosting Johnny Carson this was now 800 years ago I was about the same who's Johnny Carson but but in there we names two hosts ago from Jimmy Fallon of the time so so we explore bees and and I didn't this stuff I didn't know as I made clear in that interview right that bees when they're at in the hive and they're just sort of there's a waggle dance that they do where they flap their wings and and shake their butts yeah and the jiggle their their abdomen and they're communicating with each other not only distance but azimuth and and you know they're giving coordinates again where they just came from yes and so it's three coordinates if you want to know something in three-dimensional space you need three coordinates so you need in this case would be azimuth altitude and distance that would uniquely get you to a place they are communicating this and as far as we can tell we can justifiably say these are using abstract symbolism to communicate information and that's what mathematics is Wow so this is cosmos at its best where it just gets a cosmic perspective in this case a an earth-based biological perspective on what you always thought you in your relationship to the world around you mm-hmm that's uh I gotta tell you that's it's actually um somewhat elegant and poetic no I agree I agree yeah now Chuck you didn't I'm surprised dating cue in on the fact that I did not answer his question whether we've received signals from aliens yeah I I know you said I'm not authorized and he kind of let that go yeah yeah but so [ __ ] but here's that here's why I didn't again but see here's why I didn't I let it go because I've actually been with you in your office and eavesdropping while you were on the phone with somebody from the Department of Defense and I was like you know what this ain't none of my business I only know drones coming over my house I'm not even gonna ask him what that was about I'm like I'm not even gonna ask what that was about is none of my damn bit man yo bismillah Road hovering outside your engine window that's all I'm saying here's my point the we somehow believe that the government is some all-knowing all-powerful entity where if aliens were communicating with earth that somehow only the government would receive the signal right well the government doesn't have the biggest telescopes in the world astronomers do and we're not part of the government we're a network of folks and we communicate with each other all the time we share data and there's a scene in the movie contact with the Jodie Foster character is receiving signals from aliens and the government comes in we're gonna shut this down is it and she said no not until I send out this email she said - who - everyone right they got a signal just to the US military it's a signal to everybody yeah well and you know I mean somebody like you probably has to say that here's here's my final thought before we go on to our next half of this segment with Carolyn Porco okay good friend and colleague here's a question that I just live with okay we say let's look for intelligent life in the universe that's what the eye is in SETI the search for extraterrestrial extraterrestrial intelligence all right that presupposes that we are the measure of the intelligence we're looking for okay well get a species that's slightly more intelligent than we are okay okay would they a judge us to be intelligent and even if so or not would they be able to communicate with us so for example you can rank quote below humans other intelligent life forms on Earth so dolphins elephants big brained mammals they're chimpanzees are we having a conversation with any of them are you sitting down with the chimp you see well what do you feel about the state of the world today no no we have not had any meaningful conversation with any other life form that we would consider intelligent that's slightly less intelligent than we are why believe that some other life form slightly more intelligent than us could sit down and have any kind of meaningful conversation with us that's the skepticism with which I approach this search so really we could be Joey from friends looking for Jim Carrey and Dumb and Dumber and aliens and aliens are just like look at these idiots and there's no way there's no reason to talk to them no it could no no I can do one better than that okay Stephen Hawking telephoning Albert Einstein and the aliens will say these idiots that is too fun oh my god so oh man that's so crazy think about this yes it's like two of the smartest people in our human existence yes ever and they're talking to one another and the aliens here two babies just going oh my god that's scary it's well we got thrown a commercial from dark talk chat room deep dive into the cosmos when we come back we'll explore episode eight with a guest on the show Carolyn Porco a friend and colleague and she was head of the imaging team at the Cassini spacecraft ascend we're back from break Startalk deep dive now we're gonna talk about episode 8 of cosmos possible herbs titled the sacrifice of Cassini sounds biblical doesn't that check first of all it's a great episode secondly I will never forgive you for making me feel sorry for an inanimate thing so I was so sad I was so sad for Cassini I was like oh my god Chuck and you either had nothing to do with it let's bring someone on who did the exact and you had a real access to emotion all right let me bring on Carolyn Porco she's a friend a colleague of weird about the same station in life professionally so we've known each other like since graduate school Cara how you doing Carolyn I'm doing great I'm actually doing great excellent and and I've always called you madam Saturn yeah that was with deep affection were you okay with that I love it Neil I really love it I have to thank you for it okay one of the best nicknames I've ever had I had I had older brothers so you could imagine all the nicknames I had that you look great in the episode for those who haven't seen it Carolyn is in it oh yes thank you and you you've been a longtime friend of Startalk I just want to thank you for that you've been there for us many times and for those that don't know or don't remember you are a leader the Cassini imaging science team and just give us a note of what that means because people that I think they think of a spacecraft if just maybe just one antenna or something they don't know the full sort of getup of what these things are the Cassini spacecraft carried something like 12 investigations and one of them was a camera system which really meant there were two telescopes instruments instruments and so the Cassini instruments set were two telescopes we call them cameras and they operated mostly in the visible portion of the spectrum so they basically saw what our eye see we went a little bit into the ultraviolet a little bit into the near-infrared but it was basically the extension of our senses they produce the highest resolution images that were taken by Cassini and so the scientific objectives that the imaging team my science team members and I wanted to do were very broad in scope they covered everything you could see from the atmosphere of Saturn the atmosphere of Titan the surfaces of the satellites and also their orbits determining their orbits I just want to emphasize because your detector was slightly better than our eyes in the spectral range but it was basically seeing what we would see if we were strapped to the spacecraft yes exactly that's what a minute saying they're like an extension of our eyesight do I want to say though that you're where our eyes are much better photo metrically than our cameras were but that's another story too so anyway we our science objectives were very broad and our priorities and science anyway were to pick up where Voyager left off and so we wanted to make sure that we could see down to the surface of Titan because Voyager never saw the surface of Titan we wanted to look for Titan one of Saturn's moons one of Saturn's moons its largest moons with a very thick hefty atmosphere and we wanted to check out whether Enceladus had plumes coming off its surface because that was one of the ideas that were that was on our brains when we put Cassini together one was the e ring of Saturn created by the plume coming off in selling us and then we the only ring in the Pentagon last I checked so now we have a neat ring around Saturn oh yeah the way the Pentagon is just as designed there's five rings aren't there so anyway we wanted to do a lot of scientific things and so it was very big very big job and we did all that we saw down to the surface of Titan and we were the ones who first saw the lakes and the largest sea on Titan we found the plume and the geyser is coming off in celle dhis we found new moons new rings new phenomena we saw mind-blowing details and just incredible things that we even things we did not expect to see in the rings of Saturn so it was just it was an amazingly productive mission scientifically so the moon I just say my my other priority was to make sure that we presented our results in the most inspirational and clear manner possible and and I really wanted very much to make the rest of the world feel like they were riding along with us by just making our images gorgeous so that was another very high priority ok so but this didn't come from nowhere because reading your resume you had some significant overlap with the voyage of the very Voyager mission that you're saying this is the next best set of images that we would get of Saturn Voyager launched in the 1970s how old could you have been back then so I think what you're getting at is for you want me to say that I was part of the Voyager mission I think that's why I think I got that on your resume is that right yeah yes yes and and believe me that was like the best thing that ever happened to me I feel like I've led I've said this a thousand times I've led a charmed existence and being being part of the imaging team on Voyager was was just colossal II good but I I did my thesis on Voyager data of Saturn's rings and then by the time I graduated graduate school I was added to the imaging team and helped plan the yeren his fly by in the Neptune flyby so that's why I thought I don't know why actually but I thought I hell I'll leave that steam going to Saturn and that's that happen well if you have the pedigree coming in then you do you become the obvious choice I guess so I don't know but let me add to that in Voyager of course Carl Sagan was very active with Voyager so and I remember how much care he invested in communicating the results of Voyager to everybody and not only with his sort of fireside manner but he was on Johnny Carson The Tonight Show doing so and scientists never were on The Tonight Show so did any of that kind of legacy spill over into you for you to say standing there flat-footed that when you're taking these images of Saturn's worth Cassini you want to make sure they're they come across to the public in the most inspirational way where did that come from well okay so I cannot deny that Carl was a big influence and you know everybody in our generation loved him I cannot say the same for his colleagues who quite resented and some would look down on him for what they called grandstanding just to be clear our generation is slightly about a half generation younger than Carl Sagan so we were not sort of competing faculty and we were studiously on the rise we were students on the rise we're actually one Jenner he's 20 years older generation so so anyway you know he was just very inspirational to me but you know my desire to do the images in present them in a beautiful way actually goes back to the fact that I don't know if we have time to talk about this but if I'll just riff and you pull out of this anything you want it goes back to the fact that on Voyager the images were processed in you know red green blue color and all that only for the press conferences I mean that had never been done before that people actually put images together just to get the public excited the public didn't matter to all the the mission people that came before Voyager and came before Carl so I saw that they did this just for the press releases and they they weren't the best they weren't what they really could have been and in fact there was a member of the press corps he was an amateur astronomer as name was Andrew Young and he criticized the Voyager imaging team for not doing a better job at making the images more presentable so I'm a young scientist yeah at really standing up at press conferences saying you guys really you're falling down on the job here and I made it I made a big mental note of that and I when I became the team leader I thought check I'm gonna do that I'm gonna make sure they really look good so that was also a motive for me to do it and and you know because you do this - Neal you just you know you want to share it's just the joy of sharing knowledge and how much better to convey the knowledge that we're finding than to have an image people really connect with images it's you know it's that link between our visual field and our cortex and you know the images like get right in there is a hook so I mean it's amazing that here you say this now I shouldn't say amazing it's it's very cool to hear you say this now because in 97 when you guys are launching we were not living in the age of the image which is where we are now yes so you know here we have Facebook and Instagram and you know the Internet and we live in an image driven culture right now and so you are literally I would say 17 or 18 years literally ahead of your time that's no that's got to feel good well it does it feels very good but understand what made that the era of the image happen is the Internet in Voyager days when we were sharing images we weren't sharing images over the internet because there wasn't people were mailing hardcopy images to each other wait are the three of us on rocking chairs on a porch right now I don't know I have to say sometimes I feel that way Carolyn how's your rheumatism I think my knees tells me is gonna rain tomorrow so Carolyn I think one of the more memorable images memorable for it's not so much for how spectacular look but for what it contained was the pale blue dot and could you give us a moment about what what you remember about the pale blue dot back under Voyager and what was your attempt to reprise that with Cassini okay so I think as you said and it's clear the image itself wasn't the most spectacular and it was but but it was a fabulous idea and I often say this I know maybe it sounds I don't know what it sounds like but I'm proud of the fact that I came up with the idea independently of Carl we were both trying to work it through the JPL Voyager project he was three years I think before I was but Jeb propulsion labs in Pasadena California yes that was that was Basecamp for Voyager is that correct that was that was the days when the conduct of a mission was entirely centralized at the at the NASA center in this case it was JPL that didn't happen on Cassini but on at JPL everything happened that you on Voyager everything happened at JPL and just just a just to catch people up the pale blue dot is an image of Earth taken by Voyager went after Voyager past Neptune looking back towards the inner solar system and then you see this small dot barely filling a few pixels not just a pixel okay I think it was just a pixel but it was a small little dot okay and so I'll tell you since we were talking about heart well anyway so Carl had this group of people helping him at JPL I didn't know about it I was also trying to get it done then in 1988 this is seven years after Carl or six or seven years after Carl had started to try to get the picture taken but the project didn't want to do it because they didn't want to spend resources and I - and my attempts kept hearing the refrain why do you want to go through all that trouble just to take a picture of something that's gonna be a pixel no one copped on to it no one got it Carl kept pushing it with his his small group of advocates and then in 88 I found out that he was doing that I said hey I've been trying to do it too and we joined forces and I ended up being the person who computed the exposure times okay so I did have in the end have something had something to do with his his version of the project so but what I'll tell you I'll tell you let me just say this because this is germane of what we were saying before when the picture got finally taken and Brad Smith leader of the employed imaging team his office is at University of Arizona is like three hours down from mine he calls me into his offices come in I got to show you something and he hands me the picture and it's black and a few streaks of light on it and my first impulse to take my hand and wipe the dust off it and one of the pieces of dust I wanted a wipe away was the earth and bread and Brad says exactly meaning yes it's only the size of a piece of dust so the picture itself I don't know if the picture would have had as profound and effect as it has had over time if it weren't for Carl who who layered meaning on it and made it clear what it signified and it ended up signifying a call to all of us to regard ourselves as one tribe and to put the safeguarding of the health of our biosphere and our and our environment to make them of paramount importance in decisions that we make and managing our existence on the planet and and that's why overall these years it's become a powerful meme has it not pale blue dot you say pale blue dot it immediately signifies you know the smallness of Earth we're all in this together and this is all we gotten we better protect it and it's all down to Karl he's the one who made that happen now you reprise this at Saturn right this is my pager I must have shown to the public a thousand times I and thank you cuz I love that picture and I'm glad you're letting other people enjoy this is Saturn in the foreground beautifully illuminated and there's this dot in the background and you zoom in I say whoa that's Earth so it's kind of like a pale blue dot for our next generation yes and it had a twist so here's the thing you know once you do something like you show people a new perspective you open the door to people and they see something they've never seen before they see themselves as they've never seen themselves before it kind of gives them a new self-image it redefines themselves and once you do that you can't really have that same impact again it's why lots of missions have taken pale blue dots from the surface of Mars from on the way to Jupiter I mean lots of spacecraft have done this they don't have the same effect right so so then correct me if I'm wrong was that the image you took when you had everyone look out up at Saturn and smile yes that's what I was getting at oh that's that's that's what I was getting at that I added this twist where I thought it would be it would be great well this occurred to me while I was planning it it would be great to just invite people of the world ahead of time let them know ahead of time that your picture is gonna be taken from a billion miles away go out look up you know think about your existence think about where you are I think about the uniqueness of our planet and just smile at the sheer joy of being alive on a pale blue dot and people all over the world did that it was so it was just it was great it was actually up at Saturn from Earth while you were exposing the image yes that was the directive at this that this time this is when the picture-taking window opens go out and of course I didn't want to leave out half the planet because only half the planet could see Saturn so it was for me it was just you know use the moment to to appreciate the magnificence of what's happening and smile just smile at the universe smile at being a part of it all you know it's a beautiful connecting moment though it's really cool I you know you would have thought that I being just I was the person who started it I didn't think had been thinking about it for three years by the time it happened when it when I was there at that moment I was being interviewed by the BBC I got as into it as I was hoping everybody else would it was such a rush it really was a rush it made the solar system feel like a very much smaller place you know it was it was great so let's get on to the to the sacrifice of Cassini yeah all know have you seen the episode there came a time when Cassini's mission was over and we didn't want it to accidentally slam into a moon that we might want to investigate in the future for the possibility of life because it could be microbes stowaway microbes on Cassini so we plunked it down into Saturn so let me ask you suppose someone handed you some extension money for Cassini said okay you have another five years what would you do with Cassini if you had another five-year stay of execution the governor says no kids exactly you will be surprised but I personally would do nothing because we we had that whole thing planned so well that by the time we sent it on its way the fuel was being exhausted a lot of the instruments were starting to degrade we had squeezed every delicious bit we could out of that and I would have said at that time if someone said five more years I would have said we should take the resources that would be spent here and put them to the next mission which could be better equipped to follow on from Cassini like we followed on from Voyager and now as the questions that Cassini has left behind and you couldn't do that with the Cassini instruments so then that begs the question what is the next mission well that's being debated you know these things are always very hotly contested they're people who want to go to you know you rope up I just want to interject here that it was highly enlightened of you to say to yourself and to others Cassini's useful time is done we could hang on to it but there are other missions and this money would be kept here instead of going to other missions that can extend this this question of discovery exactly so I just want to congratulate you for that level of insight and foresight for how science works okay thank you but no one ever asks me so next mission so what would we do you know to me I mean you might get different answers from different scientists but for me the most thrilling question that we have in planetary exploration before us is whether or not there are organisms on other planets the the real the real Holy Grail would be if we could find that life had originated independently of Earth I don't know that we'd be able to prove that a hundred percent because there's material that exchanges back and forth but when you get to the outer solar system like Saturn there just to be clear so people know what you mean in the solar system you can have sort of asteroid impacts on one planet that can cast rocks into space that then land on other planets so there's an exchange of material that's been going on for billions of years and it's happened a lot between Earth and Mars mm-hmm right we have Martian meteorites here that were delivered that way people have done calculations what are the chances that something from Earth or Mars could have gotten out to Saturn and landed on Enceladus or landed on Europa on Jupiter and so on so when you say microbes on other planets I presume you mean on the moons of other planets I'm sorry I mean on the moons of other planet right right yes and if so this is one of your babies right did wasn't Enceladus one of your research interests well I started out as a ring scientist and doing work in planetary rings but when we found what we found that Enceladus I was so blown away I thought this is a place because we figured out right away that it implied liquid water and the presence of liquid water we have since learned that those geysers that you see and those beautiful spectacular images that liquid water could possibly be reaching all the way to the surface I mean all the way to the surface so it doesn't really this is often said it's like a cliche but it doesn't get better than that when you're thinking about a habitable zone you want to that could have life that's what a habitable zone is and a way to sample it because with Enceladus the ocean underneath its ice shell its habitable zone is expressing itself into space so what you're saying is I think what you're saying is you could go to Enceladus and rather than have to dig through this multi kilometer thick sheet of ice if there are geysers carrying water from below to the surface then any fishes or microbes get carried with it and then they land on the surface and so you can go there and find freeze-dried fish possibly well I have I think if there was a lot of freeze-dried fish we might have seen a spectral signature of them but to be honest I've never taken a spectrum I don't really know it so you only know what you're looking at if you have a lab samples from back here on earth okay so somebody watching should go and take a spectrum of a fish well Neal's hypothesis but I don't I don't think we have fish on the surface you know we're scientists you know we're rather conservative and boring we'd be happy with microbes it's not out of the question that there could be microbes there on on Enceladus and so it's what is the process to you fly by and through a plume collect and return or do you land I mean what what how do you envision a mission like that taking place well funny you should say that because there's a big activity right now going on in the planetary science community where people are discussing that very thing what can you do with one type of mission like maybe just a repeat of Cassini you orbit Saturn and you just repeatedly go through the plume of Enceladus once every orbit around Saturn of course you'd be completely outfitted on your spacecraft with a completely different set of instruments so you'd be much more you could do much more than Cassini could do but that's a limited mission there's also the possibility you could get into orbit around Enceladus and then you're flying through the plume every Enceladus orbit which is like an hour and a half and picking up a lot of material my favorite of course is landing on the surface because then all you got to do since the material the icy portion of it anyway the the tiny frost particles go up and 96% of them come down at the surface all you got to do is go down open up your collector plates and let the stuff snow on you and then ship that stuff off into your various instruments and there's a lot you can do there because you're collecting material all the time so that's almost as good as a sample return because you already have the sample and you just put the right instruments there with your space probe and you don't need to bring this stuff back if you can analyze it on the spot right well that that's true but barren I mean I'm not a big fan of sample return because it's very risky it's very it's very expensive for what you get you just get like micrograms worth the stuff when you could have lots more material by just going there so plus if it's your mission and it comes back to earth you don't want it to be responsible for the the Porco virus that you don't yeah that's right yeah there's always that there's planetary protection that's a big issue but we have to worry about forward protection if we land on the surface so that's a that's a big that's a big thing you have to think about but we gotta bring this to a close just make quick forward protection why can't we just sterilize our spacecraft the problem is that sterilizing your spacecraft when some of the instruments that you want to carry actually involve bringing organic material with you okay I mean there's I think they're called assays where they bring material along and if you take a bit of the stuff you captured and you stick it in that little pod or stick it in that little pot you examine what happens and that's your measurement it's the organic soup of some kind yeah so so it's it's the techniques you would have to use to sterilize your spacecraft could could you know ruin your experiment so it's a it's gonna be a sensitive balance I don't know what's being actually what they're they're thinking about these days for planetary protection all right Carolyn it's really as always great talking with you here and you reflect on your life and the life of our field and thanks for joining us for this sort of recap of cosmos possible world episode eight well thank you very much for having me as always it's great to see you guys again glad you're still kicking we are still kids are always good to have you there and you've been watching possibly listening to Startalk chatroom a deep dive into the cosmos I've been your host Neil deGrasse Tyson until next week we will cover episodes I think nine of Cosmos possible [Music]

Channel: StarTalk

Views: 133,558

Rating: 4.9338059 out of 5

Keywords: startalk, star talk, startalk radio, neil degrasse tyson, neil tyson, science, space, astrophysics, astronomy, podcast, space podcast, science podcast, astronomy podcast, niel degrasse tyson, physics, cosmos, cosmos possible worlds, chuck nice, dc, marvel, hulk, gamma rays, neil degrasse tyson cosmos, cosmos neil degrasse tyson, Jason Clark, Carolyn Porco, Madame Saturn, aliens, radio waves, Cassini Imaging Team, Voyager, Pale Blue Dot, Carl Sagan, space probe, Saturn

Id: IBSrWB6N9K4

Length: 50min 40sec (3040 seconds)

Published: Mon Mar 30 2020