Finding Life on Europa: Do we have the chemistry?

[Music] so for more than a hundred years since the first limp cies of the Red Planet through large for fraktur telescopes and the mistaken impression of canals on its surface Mars has fascinated humankind with the prospect of harboring life let's jump ahead however a hundred years to right now to present day and Jupiter's moon Europa beckons with even more compelling evidence that life might exist in the ocean depths below its icy crust so good evening ladies and gentlemen and welcome to the third installment of our now virtual SETI Talks lecture series this is the month and lecture series produced by the SETI Institute in Mountain View California I'm bill diamond president and CEO of the Institute we are a 501c3 nonprofit research and education institution whose mission is to seek out life beyond Earth and understand and explain its nature origins and evolution like people the world over we're currently doing this work from home but our research education and outreach programs continue unabated kovat 19 has forced us all to rethink how we live and work and function under truly unprecedented and extraordinary constraints tonight's virtual presentation is just one example of how all kinds of organizations are leveraging already familiar tools and technologies to overcome these constraints and state mission focused the set of talk series is usually presented live at s RI International in Menlo Park California each lecture or panel discussion is video recorded and they live on through our SETI Institute YouTube channel or you can find over 400 presentations and interviews and panel discussions covering an extraordinary array of space science topics so we invite you to take a look at our YouTube channel and just do a search and have some fun and and take a journey in space science and exploration with the SETI Institute in our live presentations we like to pull the audience to find out how many are attending a talk for the very first time so we're continuing that tradition in this virtual environment and asked you to let us know if this is your first SETI Talks experience you will see the screen a poll that will give you the opportunity to answer and let us sit yes you've attended before yes you've only done so but online or no you haven't so let us know and then we'll share the the poll results with you later on it's always kind of fun to see who we're reaching so tonight we're taking you on a journey to Europa SETI Institute astronomer and director of education and public outreach dr. Simon steel will lead a fascinating discussion with two subject matter experts on Jupiter's most tantalizing room before turning over the podium to Simon however I'd like to pause briefly here to say something about a very special event taking place later this month we're all familiar with may is the month of graduations and late spring weddings of Memorial Day and the prelude to summer but this year may also marks a very special anniversary and that is the 90th birthday of our own Frank Drake SETI pioneer emeritus trustee of the SETI Institute member of the SETI Institute science advisory board we actually had a meeting today and Frank was there and creator of the now-famous Drake Equation if you've never heard of it you probably don't belong here but we will give you a chance if you've never heard of it google it look it up it's the Drake Equation and next Thursday May 28th is Frank's 90th birthday so it would be really fun would be really great would be to hear from you and to have birthday greetings coming in from all over planet Earth to wish Frank happy birthday so if you'd like to send a message send us an email and the email address you want to use is info at SETI dot org info at SETI o-r-g and stay happy birthday it would be fun for Frank to see greetings from all over the place he doesn't know I'm doing this tonight so that would make it even more fun but now without further ado let me turn the microphone over to Simon who will introduce tonight's panelists and we'll moderate the conversation Simon okay great thanks Bill and good evening everybody from all over the world probably listening in tonight so what if alien life were thriving in the ocean beneath the icy surface of Jupiter's moon Europa recent observations of Europa from earth-based telescopes and reanalysis of spacecraft data have increased the confidence for the existence of Europa's ocean the possibility of a thin plume of water in 2019 being ejected from Europa so focused as reenergized the community which is now looking for a new way to answer these questions could a spacecraft travel through one of these plumes sample and analyze it and confirm the existence of life in the hidden ocean what kind of biomarker should we be looking for ultimately could we actually land a probe on the icy crust and explore the ocean just as we explore the oceans of Earth so these are these are all questions and in a moment I'm going to introduce tonight's guests who are seeking to answer these and more and when the speakers have presented their work we're gonna have a little bit of a discussion and then we're going to open the floor to questions from you of the audience and what we would like you to do is to post these questions in the Q&A box of zoom and our two moderators from Matisse and Rebecca McDonald will be fielding those questions to the panelists so that's something to do at any time please pop those questions into the Q&A box okay I'm just going to introduce the two speakers and then we'll listen to their presentations the first week is gonna be dr. Cynthia Phillips she is a planetary geologist at the NASA Jet Propulsion Laboratory in Pasadena California she's a project staff scientist and science communications lead for the upcoming aerobic Lipper mission and also works on a variety of future mission concepts to land on the surface and explore some surface of Europa and other ocean worlds as scientific research has involved small-scale surface processes and surface subsurface exchanges on icy surfaces that's a lot of surfaces as well as interests in scientific image processing remote sensing impact craters service geology and geophysics dr. Phillips received an AP in astronomy and astrophysics and physics from Harvard University PhD in planetary science for the minor into your science from the University of Arizona and she spent 15 years as a so scientists here at the SETI Institute before joining JPL I gotta introduce as well dr. Jill Micucci she is a polar microbial ecologist who studies ice-covered Antarctic ecosystems she's an associate professor of microbiology at the University of Tennessee Knoxville and a research interest include extremophiles and astrobiology dr. Micucci has served as a member of the NSF science advisory board to the u.s. ice drilling program office and share of its subglacial access working group she received a PhD in Antarctic microbial ecology from Montana State University and has remained interested in the structure and function of microbial ecosystems below the ice ever since geo has participated in numerous Antarctic field projects including investigations of blood falls maybe with him worried about that and the first sampling of an Antarctic sub glacial lake Lake Williams which obviously is very relevant to the topic tonight so welcome Cynthia and Jill lovely to speak to you I'm gonna invite both of you to speak for around four minutes and then then we can have some discussion so Cynthia over to you to start a conversation excellent thanks Simon and hello everyone let me share a picture with you so here's your oh but now you can see it you can see how gorgeous it is so this is the world that again it's about the same size as Earth's moon but now that you can see it you can see how different it looks the surface is covered with a bright smooth regions that are made up of mostly of water ice and then there's darker areas that we think are made up of non ice materials that have been mixed in with that ice on the surface we can see cracks we can see ridges we can see places where that icy surface has been broken up and we think that Europa is one of the best places beyond the earth to look for life and this is because we think that it has the planetary ingredients for life and when I say life this is really life as we know it so we think that life that we find here on the earth it liquid water it needs the right series of essential chemical elements those are things like carbon hydrogen nitrogen phosphorus sulfur oxygen um it needs some kind of energy source so chemical energy so that it can sustain reactions that can help life to grow and thrive and reproduce and change over time and then finally we think that life needs stability we think that for life to form and evolve and change um you need to have a stable environment you need to have a place where there's enough time for these reactions to take place and we think that Europa meets all of these requirements in fact we think that Europe is one of the best places in our solar system to look for life beyond the earth a lot of people like Mars and you know Mars is great but Europa has an ocean that we're pretty sure is there today that has more water than all of Earth's oceans combined and here's what Europa might look like below its surface so this is an artist's conception here that shows what's going on at the very surface of Europa where we have regions we have cracks we have places where maybe material from that liquid ocean is moving up through the ice shell and could make its way to the surface this isn't a crazy idea we've actually seen plumes of material being ejected from the surface of a tiny moon of Saturn called Enceladus and so it's possible that such plumes could also be existing on Europa although we haven't found any really definitive evidence of those plumes yet so on Europa there's a couple of really interesting places to look for life so there's the surface of course but one of the problems with the surface of Europa is that it's not like the surface of the earth there is no atmosphere and the surface is bathed in in punishing radiation so you can see the charged particles in this image that's material that's accelerated by Jupiter's strong magnetic fields I mean it radiates the surface so if any life was exposed to the vacuum at temperatures well below zero we're talking temperatures of about a hundred Kelvin on the surface and to this punishing radiation if any life did make up there you know those fish aren't gonna live for very long and we don't actually think there's fish on Europe unfortunately but if you go down below the surface as you move further down it turns out that ice is a very good shield it could help to protect the subsurface for some of that radiation and it's possible that inside those ice layers there could be pockets of liquid water you can see there's some ice fractures and veins maybe in this ice layer we don't know how thick that ice layer is we think that it's at least 10 kilometers maybe thicker so maybe more like 20 or 30 maybe there's places where it's thinner we know from measurements that have been taken by a previous spacecraft to visit Europa that the whole layer at the surface that includes the ice and the water is about a hundred kilometers or so so below this ice layer is this liquid water ocean and so if we're thinking about places where life might want to be the the cracks and fissures and maybe melt lenses or kind of Lake like inclusions in the ice layer are a good place to look another good place to look is at the bottom of the ice layer so where the ice touches that ocean layer that could be another good place where life might like to be but a really intriguing place also is at the bottom of the ocean where the ocean touches the rocky interior of Europa and there it's possible that we could have hydrothermal events like we see at the bottom of Earth's oceans and as we know from studies of the deep oceans of Earth we know that there's there are amazing ecosystems at the bottom of Earth's oceans and so it's possible that life could survive and thrive deep down at the bottom of your oppa's ocean and so all of these are very interesting places where we could look for life but again I'm a geophysicist I'm a you know planetary geologist I don't study life and so that's why I'm so excited to get to chat today with Joe who's an actual card-carrying biologist so I'll turn it back over to you Simon wonderful thank you very much indeed just before Joe starts and not to intimidate everyone we now have four hundred and forty-one people line welcome everybody from Florida Chile Christchurch New Zealand Santa Fe India and Lima Peru so welcome everybody from around the world and I'm gonna hand it over to Jill to take up the the biology flag for this this evenings source all right well thank you so much I'd like to thank SETI for organizing and invited me and I'd like to thank you all for tuning in from all over the place to talk about one of my favorite topics now I'm gonna try to share my screen with y'all all right are we there yep good okay sounds great um so tonight I'm psyched to talk about one of my favorite places and this is Antarctica and it may be one of the closest analogs we can get to on earth that are like the ocean world set Cynthia just described and as you can see from looking at it it's just a big continent of white it is about the size of us and Mexico combined and it houses 90% of the Earth's ice and it's been called a big dead place and you can see from these images why that might be the case it's also one of the places where the coldest recorded temperatures on earth are it doesn't get to europa surface temperatures but it does get down to about minus 89 degrees C was recorded once at Bostock station and that's about a minus 128 degrees Fahrenheit and so what this looks like to me though is a microbial ecosystem I know folks usually think of penguins and seals but if you can get into and below the ice it's a really great place to study cold loving microorganisms and pretend you're on an ocean world like Europa so how do you go from this space view of Antarctica and find where you might find microbial life and so I'm going to take you to a place right here in East Antarctica it's along the edge it's called the McMurdo Dry Valleys and to look for life in a place like this you would first have to look for where the water might be and so you'd come in from an aerial view and look from some form of remote sensing you will try to get a little bit closer and take some high-resolution images and see if you can find the potential spot that looks intriguing and so here is a picture a Taylor glacier and this isn't actually a very intriguing place and then once you find a great place that you may want to sample maybe you can go there with some fancy instrument this is actually a picture of a thermal melting probe called the ice mole that can navigate through ice to collect samples unlike Europa I can walk up to some of these features and actually collect samples by hand and so here in my purple gloved hands is a sample of subglacial liquid and then if you're lucky enough to get a sample then you can look for life these little squiggles and dots are what I get excited about these are actually microorganisms and then if you can bring a sample home and back to your laboratory you can take some really fancy high-resolution electron microscope images and get to really get to know these microbes with their cool appendages like so the challenge here really is a challenge of scale right so some of these remote sense images are taken at a kilometer but a microbe lives at a micrometer and to just put that into perspective for you I'm here in Knoxville Tennessee and the SETI Institute is out in Mountain View California and that's over two thousand miles and looking at that span of distance for something about the size of my pen tip is what it's like to look at that level of scale for a microorganism but it's doable right when you sense remotely you can potentially find little squiggles that actually are inference about where liquid might be you can see whether there's salts there maybe there's a brine you can look at maybe rock permittivity and potentially see changes in chemistry from some of the remote instruments that are used by NASA and so maybe you can identify a place where there's good liquid like Cynthia was talking about with the subsurface ocean and that to me spells out habitat and so these could be potentially cool places once you get closer in and you find it place to sample maybe you can look to see if there's anything accessible from the surface and so these would be some of the plumes that might be coming out on Europa in Antarctica this is places where subsurface liquid might leak out to the surface and be more accessible for us to sample even though the ice on Antarctica is not as thick as Europa it still can be hundreds of meters if not kilometers in places and so it's still a technical challenge to collect these samples so if you can find a place at the surface maybe aerial image will reveal this and last if you can be lucky enough to get one of those samples this is where you can potentially detect signs of life and some of those signs of life maybe a little bit more ambiguous to determine what they're coming from right so like bio signatures of those essential chemicals that life needs but maybe you can see other clues such as minerals that are precipitated in such a way that they're only made by biology right and so this is an image here of micro muley produce calcite crystal maybe you'll also find features that show evidence of life rearranging its environment around it like the base of sea ice this is an image here of algal blooms that are growing at the base of sea ice here in Antarctica possibly something we might see on Europa and if you're lucky enough to get some type of information biomolecule right like on Earth DNA then you can really start to elucidate a lot of fascinating information about the lifestyles of these organisms wonderful thank you very much and and of course what we're interested in here is the interface between both of both of your researchers and it's a shame at the moment Jill we can actually transport you to the so well maybe you're probably happy that we can't transport you to the surface of Europa but be interesting to hear what you think you would see if you were there so Cynthia just a quick question about Europa of course we all hear about the bizarre the habitable zone around a star where there is liquid water now now this moon of Jupiter this is five times further away from the Sun than the earth is that's a long way outside the habitable zone and so what is going on with this this this moon with an ocean and and how do we know for sure that there's an ocean underneath all that ice yeah that's a great question Simon so so yeah we when we first started thinking about the habitable zone like you said that that was defined as the the distance around a Sun where liquid water could be stable at the surface of a planet and that seems to make sense because then we look at our solar system and we're like okay Venus is too close to the Sun it's too hot liquid can't be stable there Mars is a little bit too far away it's too cold but you know here we are in the habitable zone you know the Goldilocks zone where Earth is just right and that's a story that works in this very sort of simplified simplistic view of our solar system but as we've studied our own solar system more and also as we started looking at extrasolar planets so other solar systems that are around other stars we started to see that there's a huge diversity of solar systems out there and there's potentially a huge diversity of worlds that could be habitable and so what's going on with Europa so again it's this little tiny moon and it's yeah it's it's far away from the Sun so the Sun just looks like a really bright star in the sky so the surface is cold there's no atmosphere but what Europa has going for it is something called tidal heating so there's this elegant dance where three of the large regular satellites of Jupiter there's I oh there's Europa and there's Ganymede so every time Ganymede goes around Jupiter once Europa goes around twice and IO goes around four times this creates what's called a resonance where the satellites line up at the same place in their orbit each time and they tug on each other and those tugs those gravitational poles mean that the orbits stay slightly non-circular um and that's important because generally if he just had one moon if it was orbiting Jupiter the orbit would turn circular over time all of the kind of the bumps wiggles and differences in distance would even out and you would just get a nice perfect circular orbit but because of this resonance the distance from say Europa to Jupiter varies sometimes it's closer and sometimes it's further away that matters because of tides so Jupiter is the most massive object in our solar system and Jupiter's gravity pulls on Europa's surface when Europe is a little bit closer to Jupiter the surface gets tugged on it gets stretched and then when it's a little further away the surface goes back down so if you were standing at a point on Europe a surface it would be like the ground would go up and down maybe as much as 30 meters over the course of this tidal cycle and so tides happen on the earth that's what happens when the moon's gravity tugs on the earth and that's what makes the oceans move and slosh back and forth that same process happens on Europa but there's so much more force that we think that that produces titled heated and that heating takes place we think deep in the ice layer of Europa and it squishes and pulls in just that frictional motion creates Heat and so there's enough tidal heating that it could keep your opus ocean liquid over the whole age of the solar system we think this resonance has been there since you know for the last four billion years so since very soon after Europa and Ganymede and IO and Jupiter formed we think this resonance is very old and so we think that it's that heating that's created this ocean that could have been there for four billion years Wow so it's being stretched and squeezed and that like a rubber ball and if you do that enough and there's an experiment you can do at home you would feel that all heating up and that that's Jupiter's stretching and squeezing with the moon's so you know we needn't limit ourselves to the habitable zone when we look at exoplanets and look further for ocean life that's that's quite amazing she'll tell us a little bit more about a day in the life in Antarctica and and of course you're you're you know looking for biomarkers as things that indicate that life is present or maybe was present not necessarily there for the little little fish or bugs themselves tell us how you go about planning that that expedition and what you're looking for yeah so I mean it's one of those things where you have to go in with an open mind you're not gonna see trees or or fish or other things lying around you're gonna just see what looks like barren rock or ice and so it's really challenging to find that microbial life within that and so the I guess the process first starts when you imagine where you want to go to look for life and so it's really a strong collaboration right you have to work with two physicists and biologists and other scientists so you can collaborate and think about where these pockets for life might be much like Cynthia was talking about how it was a surprise to find these oceans on Europa for a long time we didn't think there was these large lakes below on the ice sheet of Antarctica but when scientists use modern tools and looked back over old radar data they found hundreds of lakes below the ice and so when microbial ecologist hears that kind of story then I think that's where I want to go and so that's then where the logistical package starts to come together where you think okay what do we need to get through the ice well I guess we need a drill of some kind and so then you have to reach out to engineers and work with them to help you design tools to collect your samples and then you start thinking about your basic human needs like how do we get there what kind of protective clothing do we need what kind of sample gears so in the one sense you're you're trying to think about all the things you need for your science but then you're also trying to think about all the things you need as human to be operating down there in and living and sampling yeah because you know you're complaining about Antarctica you miss it's cold and you know where it and everything but this of course is nothing compared to Europa it's the extremes of what's on the surface of Europa a quite phenomenal aren't they as Cynthia so let's tell us what it would be like for an expedition they're an expedition to the surface of Europa would be a very short lives unless you brought a whole bunch of protective gear basically this that so there's there's no atmosphere so you'd need like a serious vacuum spacesuit it's really really cold so you'd have to stay warm but even beyond that you'd have to deal with that radiation the radiation is just punishing if you were just in a standard kind of NASA issue moon type of spacesuit you could probably only survive on the surface for you know maybe tens of minutes before you got a lethal dose of radiation so the surface of Europe but really is not going to be a good place to build your next you know resort um but I you know and I think that one of the good things about Europa is that ice is a pretty good insulator and so if you can get down below that ice somewhat then the radiation is really a lot better and so I think that you know eventually when we go and build our field camps and our you know luxury hotels on Europa they're gonna be buried beneath the ice and maybe you have some nice like radiation proof stones or something so you can see Jupiter in the horizon but you're probably not going to be walking around the surface too much and that's actually a concern so we're thinking about a future mission called Europa Lander that would actually land on the surface of Europa and dig a little bit below the surface and take some samples and bring them on board for study and the radiation environment is certainly one of the constraints that we're dealing with even a radiation hardened spacecraft where you put most of the instrumentation inside of a shielded vault to help protect all of your electronics um even something like that can probably only survive for you know a month or two on the surface before it gets totally fried and I didn't mean to so Jill if you were you know and we'll come back in a moment Cynthia to talk about the Europe a clipper mission what's the things Jill are you looking for as as a biologist or somebody who studies biomarker and you know the effects that life has on environments what sort of things would you be looking for in a mission to Europa either sort of look getting close to the surface obviously you'd like to land something and maybe we can talk about that later but but what sort of biomarkers what sort of things are you thinking you're looking for on the surface Oh on the surface I was just gonna say what Cynthia was saying about human landers it's the same thing that I would expect for microbial life right like below an ice sheet is actually pretty comfortable place to be and you have a lot of potential for nutrients and energy sources coming from for example these hydrothermal vents but if I was only able to access the surface given all the logistical constraints I would look for places sorry there's a I would I would look through places of differences right like edges so Cynthia pointed out some of those what looked to be salt rich stripes on the surface right so maybe these are places where parts of the subsurface ocean have come to the surface and in there potentially some biomarkers can survive we see this in Antarctica granted it's not as harsh on the surface but we do see evidence of subsurface life eek out onto the surface either through metabolic substrates so things that micro organisms have breathed out like we breathe out co2 microbes breathe out all sorts of metabolites not just energy metabolites like methane or co2 but other volatiles that talk about their lifestyle in a chemical form and then maybe also some of these mineral precipitous may be the salt crystals are shaped differently because you have they've interacted with life in some way okay because it go until we can get drilled down as you say wewe need to have stuff hopefully rising to the surface and leaving some sort of deposit on the surface that gives us gives us a hint that something might be down there yeah yeah it's still probably beneficial to get a little bit below the surface though if you if you possibly can yeah Cynthia tell us about Europa clipper and you know some of the design constraints that that has considering the the harsh environment because that's that's that a limitation isn't it on on how close and how long you can stay around your OPA yeah absolutely um and so if you were on Europe I'd put up my ad my fun backdrop that has some dinosaurs that no radiation hardened spacesuits so you certainly would need some of those if you were gonna be on the surface but um so you're up the Clipper is a great mission that we're working on at JPL that's gonna launch sometime and in the the middle of this decade and when you think of a mission that's gonna map something from orbit you usually think about missions to places like Mars where you can just go into a nice stable mapping orbit and you're able to you're able to just look at the surface from a nice consistent view and misses like that are great to places like Mars but for somewhere like Europa unfortunately if you were in orbit around Europa you'd be subject to that same punishing radiation and so a mission like that could you know maybe survive a month in orbit and that's just not enough and so unfortunately Europe Leclaire it's a mission that's going to have multiple close flybys of Europa but it's actually going to be an orbit around Jupiter and so this was a really clever strategy that the the mission planning folks at JPL came up with where basically you you go by Jupiter so you you you circle around Jupiter you go in for a close flyby if Europa and as you go in you're kind of going into that radiation hot zone it's sort of like you hold your breath you get as close as you can to Europa you turn on all your instruments you go flying fast it pretty fast you take all of your clothes approaches observations and then you get out of there you go back into this orbit back around the other side of Jupiter it's kind of like you takes deep breath you know you've been underwater you finally get to breathe again and then you have some time the matter of you know days or so you know maybe as much as two weeks to finish taking up your observations to process them onboard the space to downlink them back to earth to uplink the new plans for the next orbit and then you go in again for another flyby so what Europe will be able to do is have about 45 or 50 close flybys of Europa over a couple of years in the Jupiter system and so that means that we can map a very large percentage of the surface at very good resolution and we can we can do things that we just wouldn't have been able to do in a shorter lifetime mission that was actually in orbit around Europa okay what sort of resolution I'm thinking you know what if for instance you had you wrote you had you wrote a clip of doing the same thing over and arctica I'm wondering if if the resolution you're getting for Europa would be enough Jill to actually recognize some of the features she's seeing in Antarctica mmm that would be fabulous but so the the highest resolution data that we're gonna get from Europe and clipper it's probably going to be about like half a meter per pixel or so I mean it depends on the the actual altitude of the close-up approach flybys and so you know that's that's pretty amazing compared to the highest resolution images that we got from the previous spacecraft from the Galileo spacecraft that's the only close high resolution data that we have for Europa so far and the highest resolution there was about six to 12 meters per pixel and we only have a very small handful of images at that resolution from Galileo so we're we're certainly going to be much better with Europe a clipper and we're really looking forward to that that what is high resolution data to us but for someone like Jill who can actually go and walk around in her field site I'm sure that that would be you know dramatically insufficient to see these actual surface features but that's where the ties between what we see with the remote sensing data and then what we actually see from say aerial imaging so so like like those pictures that Jill was showing at the beginning where you start zooming in from the orbital data into the closer and closer data until you finally get to the ground that's where those links are so important is that we need to understand we have our remote sensing data we have our orbital data or our flyby data we need to understand what that's actually going to look like and mean when we get down to the surface instruments on the really exciting because there's like the ice penetrating radar for example and so it could potentially reveal like I showed in that first image pockets of dynamic ice within the ice cover as well as may be thinner spots within the ice and so these are all things that while it might not be that that high-resolution picture of a crack in the ice that we really want it's going to show um potential habitats and start to really focus you in and show some potential edges and that's where we tend to find life when there's edges involved that's nice and as you say if you got radon you'd detect me you know we're saying ten kilometres thick for this ice maybe there are regions where it's much thinner and that will be a potential landing opportunity possibly yeah so asking both of you about these plumes we we know I've seen much more detail the plumes on and salad at Enceladus because that was from the Cassini mission tell us a little bit about the plumes are on on Europa Cynthia and then Jill what sort of things with if you could pick up material from that plume what sort of things would you be interested in seeing in that material so it would be really cool if there were active plumes or geysers that were ejecting material from Europa surface into space we haven't we haven't seen any definitive evidence yet that that I would say makes me believe that pollutants exist we've seen a lot of sort of intriguing hints mostly through ground-based sir you know earth-based observations either taken by ground-based telescopes or from Hubble Space Telescope as well as reanalysis of data from back when the Galileo spacecraft was in the Jupiter system and you know it we there's been some sort of single or maybe multiple data point detections but we're really at the limit of what we can do with terrestrial datasets and so the discovery of plumes on Enceladus means that plumes on Europa it's not crazy talk rate it certainly is plausible that plumes could exist one thing to note is that the surface of Europa that the gravity of Europe but it's much higher than Enceladus just because Europe is a lot bigger and so while on Enceladus you can have plumes that are you know they go you know more than the radius of the satellite so they're really there once you know where to look they're pretty easy to spot on Europa they would be much smaller so they're gonna be a lot harder to find than they were on Enceladus and even the Enceladus ones were very tricky until we knew how to find them so so yeah so I would say that plumes are Europe but are an intriguing possibility it hasn't been proven yet but Europa clipper is absolutely going to look for them and one of the cool things about Europe a clipper is that if plumes do exist we'll actually be able to fly through them and sample them with some of our onboard instruments that we'll be able to measure the composition of the dust and the gas that's thrown out of the surface I mean those instruments will work even if there is no plumes at all because small concentrations of particles are just naturally thrown off the surface from that radiation so yep tell us about the plumes will experience a lot of any of the material and then we'll experience a lot of change from radiation etc being to the surface but it still could tell us composition of what source those plumes right so maybe learn more about the composition of the ocean reveal if there's been rock water interactions which means the water has moved through the the sediments at the bottom of the ocean and circulated through the ocean that can tell us about potential energy sources for microbes and if there's any compounds that have some type of isotopic fractionation it could reveal elements of selective feeding where light selects certain molecules so there is a lot of potential in the absence of being able to drill through that thick ice cover to learn a about what that ecosystem might be like I'm just interested Jill you know this at first this is a silly question is there a region on on the surface of the earth but mimics quite closely the surface of your okra and of course it would be Antarctic or maybe the Arctic is there somewhere that you see the same sort of patterns and flows in the Antarctica analog so you have to piece things together right earth is so different but that's one of the reasons why I'm fascinated with blood falls because it's subsurface marine water that slowly leaps to the surface and leaves a pattern on ice and so we can look at how subsurface minerals and microbes interact with an ice surface and then there's these fumarole features like you might see a meter in Canada or on some of our other Cascade glaciers where this geothermally heated water is migrated through the sediments of the volcano and have blasted out into the ice surface as a vapor and so I think these are great analogues where we can learn about how to better look right I always think we have to be able to do it on earth if we're gonna be able to do it in the really challenging environment get it right here before you launch the thing into space yeah well I think it's time to to open up questions to the audience so what I'm going to do is I'm going to hand over to Rebecca McDonald a director of communications and front matisse is a senior planetary astronomer at the SETI Institute and they are going to ultimately bombard you with questions that have come in from from the audience so over to you from sorry thank you so we had more than 100 questions so we are not going to be able to answer to all of them but we have already very interesting questions and most of them have been answer so far we get one question from Alex Torre with asking about the bio signature that might be detected from orbit assuming plumes exist or do not exist and if the do talk about the difficulty of taking samples to analyze them Jill do you want to take that sorry I was so that was the difficulty of collecting samples from the plumes correct so I yeah that's kind of a combo question I think first Cynthia and I you know on earth it's very different we can set up a time-lapse camera and try to sneak up on some of the brines leaking out of a place in antarctica like blood falls and then I can walk up and collect a sample or we can try to drill into it collect it but on a place like Europa you would need some type of capture mechanism so you would need something that could orbit the planet and Cynthia already talked about some of the challenges with the radiation and then you'd need some kind of net right and I know there's different types of gels and things like that but you'd have to be able to collect that sample so that you could analyze it yeah and so on the Europa clipper spacecraft we have two different instruments we have a dust detector called sudha and then we have a mass spectrometer called mass specs and so the two of them together will be able to look at gases that are ejected from the surface as well as dust particles they're not going to have something like that so they'll be able to look at the composition of material however this material is moving very quickly when it's ejected from the surface and the spacecraft is also moving very quickly and so we're not gonna it's not going to be like the the Stardust mission or some of these missions where we've actually flown an aerogel to capture particles in this very soft bed of really really low density material to bring back to analyze in a terrestrial lab we're not going to do that on your upper clipper instead we're gonna catch the particles and basically break them down to figure out what they're sort of fundamental chemical composition is so we're not going to be able to bring like a microscope to look for little tiny microbes or anything like that so it's going to be a much cruder kind of analysis but we should be able to get sort of the bulk chemical composition of the material that's thrown off the surface and that'll be a great starting point in understanding what sorts of materials could be ejected in these plumes if we see them and if there are no blooms again we can still measure the composition of the surface a bit by by seeing the material that's just ejected from the surface it's at much lower concentrations than if there is a plume but we'll still be able to detect it and measure it great Thank You Rebecca hi this question is from Andrew have the Russians found any life-forms in Lake Vostok and how does their work complement Jill's work great question so unfortunately there was no clear evidence because of the way that Lake Vostok was drilled into there it's it's it's the deepest lake it's the largest lake that we know of in Antarctica it's about the size of Lake Ontario and the drill that was used there was when you're when you have liquid under pressure and you penetrate into it through ice cover you're gonna have this upwelling of a liquid into the borehole and so it rapidly mixed with the drilling fluid it was really difficult to distinguish life from non-life in the actual sample of Lake Vostok that was collected however there's been a lot of work on the ice cover itself right and so that's why I'm interested in variations and ice cover because part of that lake water from Lake Vostok actually freezes onto the bottom of the ice and makes part of that ice that you can collect as a core and you can look at that and start to think about what some of the chemical constituents and microbial cells might be like in that ice cover does the Russian work inform our work up on sufficient Lake Whillans absolutely the one of the wonderful things about Antarctic work is that it's highly collaborative and it's an international community this is really these are really hard complex problems and so we meet together and talk about some of the challenges that we face and some of the protocols that we use so I think Vostok work had really excited the community to look for other lakes and potentially lakes under thinner parts of the ice cover which is what we did when we went to Lake Whillans it was only 800 meters of ice as opposed to the four kilometers so yeah it's an awesome question there's still so many lakes to explore so yeah we need to band together to do it we're gonna stay in the topic of Antarctica with a question from John B that's for ug our specialized are the microbes you have found in subsurface lays in Antarctica they found elsewhere on earth could we expect the same pattern on Europa that is an awesome question as well and so I showed that picture of a microbial genome on my slide and so there's a lot of information in that that those molecules right it can tell you a lot about the microbes so when you look at their family tree and who they're related to many of these sublation Lake microbes are related to other subsurface microbes that from places that we've explored on our planet right whether the deep subsurface or whether marine sediments around the globe and so there is some heritage there in terms of relation but in terms of specialized function that's what's in that genome and some of it we don't even know what it does like what some of the the genes are for but microbes in some facial environments do have unique adaptations for living in the cold for living in the absence of sunlight and for taking advantage of the food buffet that is there for them which is the crunched up rocks below the glacier so okay so that was the first part of the question and then the second part obviously yes there's some commonalities and some differences when it comes to sublation microbes in terms of what we expect on europa I mean you keep an open mind it could be really really different but some people also think there could be a universal nature to biochemistry just given the elements that are available in the universe for life to take advantage of uh Nawrocki body with water and ice and so I would expect that any life form on your Robo would have to have strategies to deal with the cold to deal with the darkness to potentially deal with salts and to be able to harness its energy from rocks great thank you very much I think this next question is for Cynthia is from Michael we've spoken about life on Europa but this may be simple microscopic life what is the likelihood of intelligent life and what parameters would have a correlation to the discovery of intelligent life that's a that's a great question I think that all of us would love to find intelligent life or even you know multicellular life like you know I take fish on your oven that would just be amazing and mind-blowing but unfortunately it's really really unlikely and the reason for that is just energy you know we talked about how life has certain requirements it needs certain certain parameters to survive and while we think that life could exist on Europe we're talking about very simple you know single-cell life may be multicellular but no complex organisms um some some folks have done basically they've looked at the amount of energy sort of energy and energy density that we think would be available in Europe with subsurface ocean and there's just not enough so we think that the chances of intelligent life on Europa are I would say vanishingly small of course you know there's there's always life as we don't know it so I'm not gonna rule out the possibility of something you know that we've just never seen that we just can't even conceive of that maybe we wouldn't even recognize as life I think that's a possibility but I think that finding you know whales or giant squid or you know mermaids or anything like that in Europa unfortunately vanishingly small and you know the information storage molecules that life on Europa might be using could hold potentially a lot of information so even though we say just in microbial cell there's still like on average what five to six mega base pairs of DNA in there that can store information and could be used in ways that we don't fully understand yeah that's absolutely true probably they're not going to be building radio telescopes to call back to us on earth and say hi but yeah it would still be fascinating and amazing to find life there even if it is you know just single celled life ok so we have a lot of questions about radiation so I'm trying to combine them do that these those are questions coming from Vice Nash run and Dutchbat so one what first a question for you Cynthia well what are the what is the origin of those radiation where are they coming from from Jupiter from Europe of some some other phenomena and then why they so were they much higher near Europa than in orbit around Jupiter and then there is a question for you JD's would this radiation have an effect on the type of life you expect on Europa considering the kind of mutation this microbiological life will find will suffer and do we see the same kind of phenomena on earth okay so starting on the on the radiation question yeah so Jupiter it's a giant planet and has a giant magnetic field and so basically what happens is that when charged particles just from you know the solar winds that are just kind of in the interplanetary space heading out toward Jupiter when they start interacting with Jupiter's magnetic field on they get accelerated and so it's these accelerated charged particles that that produce the really high-energy radiation that we experience that Europa's surface and so it's a variety of you know there's there's different there's there's different kinds of you know there's there's high-speed electrons and there's ions and there's you know all sorts of things that the folks who like to do magneto hydrodynamics look at and you know radiation studies which is not what I do I'm more of a geology kind of person but yeah but so that's the origin of the radiation and so basically the closer you are to Jupiter the higher the radiation zone that you're in and so io is the closest in and so io not only does it have the most title heating so it's the most volcanically active body in the solar system it has huge amounts of heat and it also has huge amounts of radiation as we move out so Europa is still kind of in the hot zone it orbits within Jupiter's magnetic field so um so you really have to get out further to Ganymede and even so even Ganymede has a pretty high radiation environment at the surface although than Europa and I'll pass it to Jill for the the effects on life okay yeah so I'm pretty harsh right but every time we see that like oh this is too extreme for life we find something that surprises us even here on earth right oh it's too salty or oh it's too cold or oh it's too hot so I like to be really cautious in that area in terms of what the direct radiation radiation on the ice can do is it can form more complex molecules right on an impure ice surface when radiation hits it it can make organic molecules simple ones but that can be potential substrate so if life is in a place where it's protected from the radiation but it's still receiving those radiation products I think that's actually a potential benefit for life radiation can also split water molecules and make hydrogen which is another great food source for microbes and like like I said there's always surprises microbes always surprise us there's microbes in Chernobyl that can handle the radiation coming out of that site and so again no perfect analogue but that's a place that we can study to learn more about how maybe life takes advantage of this potential energy source that seems dangerous to us but may be a great source of energy on a place like Europa hi I think this is a question from Eric I think is for Cynthia why do we not see more missions like Spirit and Opportunity in which multiple probes are sent simultaneously R&D seems to be the major expense in these missions and with the shear time it takes for these probes to travel it feels like making progress and exploring Europa would take multiple decades instead of multiple years I would love to see multiple probes being sent to different places I think that that's a that's a fabulous plan it's worked out well you know we had two voyagers we had multiple pioneers we had Spirit and Opportunity unfortunately it comes down to dollars even though you know the dollars per science is probably if you build two of something as opposed to building one still the total amount of dollars that it takes to build two of it is a lot of money and so unfortunately missions that go all the way to the outer solar system in particular they're expensive it's a long trip out there you need a lot of radiation shielding a lot of propellant Europa clipper is gonna have you know solar panels that are the size of a basketball court I mean it's a difficult place to send missions and so well I certainly would love if we had two of them or maybe we have one that goes around Jupiter and then one that we send out to Saturn or something I mean that would be amazing but it comes down to money okay thank you Cynthia so we have some interesting questions here one of them that I never thought about from Andrew with asking if it's consumer consumable that microbiological life from Earth sit in Europa at some point and vice-versa via meteorite is that this seems to happen between Earth and Mars will ever really happen also between European Earth actually I can take that one if you don't mind gel so so yeah so that's actually one of the most exciting things in my opinion about the possibility for life on Earth and that's that yeah we know we found meteorites on the surface of Mars and we've also sound meteorites on the surface of the earth that we can prove came from Mars that they match the composition of Mars perfectly so we know sometimes we say that you know Mars and the earth have been swapping spit right they've been sending rocks back and forth life could have started on Mars and then seeded the earth or vice versa you know we could all be Martians but the thing is that if you look at the dynamics while it's possible to get rocks back and forth from Mars to the earth from Earth to Mars you can't do it to Europa so even if we managed to somehow eject a rock off of the earth and it made it out toward the Jupiter system Jupiter is so big it's gravity well is so big that it's gonna hit Jupiter it's basically vanishingly impossible to send a rock or a chunk of ice from Europa to the earth or from earth to Europa and that's actually a really profound compliment because what that means is that if we find life on Mars right I'm not gonna complain I think that would be amazing it would be awesome but it's not going to be proof of a second origin of life in our solar system if we find life on Europa even if it is just those you know those fabulous little microbes that is origin of life number two the second genesis of life and if we can have life that starts not just once but twice in our dinky little solar system then you look up at the sky and you look at all of those stars that now we know the majority of them have planetary systems surrounding them so all of those stars all of those worlds all of those solar systems if life can start twice in our little unremarkable solar system you look up at the sky and life is abundant life become it goes from being a rare special phenomenon to something that's got to be ubiquitous and that to me is one of those paradigm-shifting civilization scale concepts and that's why I've devoted my scientific career to studying Europa here is a question from David any idea what causes the color in the surface stripes of Europa usually when I see red like that I expect organic compounds so when we when we look at the surface of Europa most of it so so one data point first is that most of the pictures you see of Europe are highly color enhanced they've been they've been stretched and modified so that we can really see the color differences Europa's surface is mostly bright kind of white and then there's some places there kind of a reddish brownish yellowish sort of non-white material I once called that the non ice contaminants and Frank Drake actually came up to me after a talk and said note don't call them contaminants because that's the good stuff so I always remember that and I make sure I call them you know constituents or components right because yeah we don't want to be you know Frank Drake is a really smart guy right so you don't want to be dismissive of anything he says but he was absolutely right that's the good stuff that's the nah nice materials and so we knows from spectroscopy that that material it contains some kind of either highly hydrated salts or you know so it could be things like magnesium sulfates or sulfuric acid there's a bunch of kind of compounds in that same category that seem to match the spectral features that we have so far we haven't seen any signs of organics yet um the Europa clipper spacecraft will have a very good high resolution mapping infrared spectrometer called Mies and the Mies instrument will be able to determine the composition using spectroscopy I'm much better than we've been able to do so far so we'll get more information on that we were running short on time so there's gonna be one more question from Frank but I don't want to pose another you know this is there's no money on this but but the next question that's going to come up on your screen is Mars or Europa where will we find life first and we'll see what happens there okay Brown that's question from the audience I'm very disappointed at cannot vote for this so having a question from Liana Leonardo here combined with another question - in a concern of contaminating potential subsurface subsurface life if we drill on Europe as your face and if we learn anything while drilling Antarctica lakes to avoid this kind of contamination so it's a question for both of you in fact you want me to go once you're sorry I think about that all the time I'm always worried about contamination and so we take it very seriously in Antarctica and it's really hard not to bring something from the surface into these subsurface lakes and so the best prevention I mean we clean using some of the specs developed by NASA for their clean rings the rigorous way that they clean their instruments we do that even for the instruments that we use in Antarctica but I also am very careful to take an inventory of any of the microbes that may be on the instruments that I use to collect samples and that way I know what may potentially be on the surface right and so knowing what may be a contaminant I think is really important I think once a human gets involved I call it trying to be mindful but it's we are just covered with microbes there's orders of magnitude more microbial cells than human cells and so I think it's a it's a real challenge and maybe Cynthia can touch upon how maybe the journey to Europa the time on the surface might help with that a little yeah and so when you're talking about going to Europa one of the advantages well you have a couple advantages one is you're not bringing any of those pesky humans along with you so you know you you build your spacecraft the is less of a concern for the Europa clipper spacecraft although there are so NASA has what's called planetary protection requirements that make sure that we don't contaminate other places in the act of studying them and so the orbiter will the Europa clipper orbiter will need to meet pretty strict planetary protection requirements but where it really comes into play is with a mission like that proposed Europa Lander that would actually land on the surface and so there we need to be extremely careful not to contaminate the surface not to bring anything with us and fortunately so we're not going to land humans on the surface so that's good they're not gonna be breathing all over our nice pristine location the radiation on route so while we're traveling from the earth all the way out to Jupiter there's plenty of radiation that will help to sterilize come the outside of a lot of us of a lot of our spacecraft and then yeah we do the same things that Jill is talking about where we try to very carefully sterilize everything on the inside as well as we can and we also take a very careful inventory of everything we're bringing with us so yeah the last thing we want to do is to go there discover life and then oops nope sorry that was just a hitchhiker from Earth someone sneezed on the spacecraft we do the same thing for the Mars rovers as well so so the new Mars 2020 that perseverance Rover goes through very very careful cleaning for planetary protection and we would do the same thing for a mission to Europa surface as well all those amazing questions that was was really really good there be the poll results are in and I think Mars just about comes comes ahead 183 votes to 116 so I'd be fine hand back to Bill just just one wrap-up question for both of you thank you very much for all this amazing stuff I learned so much I'm not a planetary astronomer so this is all very exciting to me so if you had a wish list for the next mission or the next experiment doesn't have to be you know off planet and you know we don't have to worry about contamination issues so there what would you like what would you like to build I want to land on Europa's surface and you know that's probably not gonna surprise anyone but it's not so much for the biology right I mean you know the biology and the chemistry and you know all of the stuff we can do it from the surface will be amazing but I'm a I'm an image processing person and so what I want I want that picture from the surface I want to actually see what it would be like to sit or stand on the surface of Europa and look out and see that ice-covered horizon see Jupiter in the sky above you it's just gonna be amazing I can't wait to get that picture so that's what I'm in it for to be truly honest no budget restrictions on this I mean I wanna I want to see that picture - I think that sounds amazing ice is a fabulous ecosystem it doesn't seem like that at first but there's really all sorts of nooks and crannies and so if I had an englis budget I'd want to create a large walk-in Europa cooler where I could set up all different types of experiments long-term experiments that like future generations could actually look at these microbes to see what true growth rate might be like in a really cold system and I just wanted to touch on Cynthia's statement about this second origin of life I think that if it happens on Europa it's gonna be really different the conditions are really different than even what early Earth was like and so I just think there's there's so much potential to learn there great thank you so much both of you and to wrap up the evening and thank you everybody else for for tuning in this will be available in YouTube I believe and Facebook as well it's streaming so I'm gonna hand back over to Bill to wrap things up all right well thank you Simon and Thank You Cynthia and Thank You Jill this was absolutely awesome and it was just fantastic to see the range of questions some incredibly insightful and wonderful questions coming in from the audience but but for to both of you it's like you know I'm sorry but I've already fulfilled your wish I mean Here I am on the surface of Europa you can see Jupiter over my shoulder there you can see the Sun in the distance you can see the icy surface I'm standing on and I've got my radiation shield up to prevent me from getting cooked like a fried chicken but know it taking social distancing a bit too far Bell yeah but I will say synthy I don't know if this is something you can get your hands on that we could at some point share with our audience but I was at a NASA autonomy workshop year and a half ago and and one of your colleagues from JPL was sharing this animated video of a future Europa mission in which a lander lands on the surface and deploys a drill basically that's you know on a cable tether that drills all the way through the ice and then it deploys another little crawler that crawls underneath the the the subsurface layer of ice and also has instrumentation to you know detect biology and the the animation is absolutely stunning in mind-blowing so that's very cool if you ever get a chance to see it but I also just like Jill Cynthia I want to comment on your your your notion about a second you know unique biogenesis I mean that that would be indeed extraordinary and you know when you're in the business of searching for life in the universe and in your own backyard you find two unique and distinct Genesis events it does pretty much say you know game over as far as life in the universe is concerned and you know long before I joined the SETI Institute and had the privilege of working with people like you I commented years ago I said you know I think what we will find and this is even before the Kepler mission is that one of the most remarkable things about life may be that it's not remarkable after all that life as a phenomena is is present throughout the universe and you know I think explorers in the future will bear me out on this but this was absolutely brilliant thank you both so much thank you everybody for joining us tonight we had at the peak over 450 folks joining us on zoom' and another 100 or so on our Facebook channel as Simon didn't know this will be available to everybody on our Facebook sorry well on Facebook yes and also on our SETI YouTube channel so you'll be able to see this anytime and share that link with your friends so please do that this was absolutely brilliant and we'll see you again next month for another virtual SETI talk and we'll be sharing information about that talk upcoming and hope to see many of you back for that or even more some of the poll results as well you know 40% of you said that you have seen and and participated in said he talks before 19 percent said you you've done it before but only online and 42 percent of you said this was your first time somehow that doesn't add up to a hundred percent but you know it's the new math that is available on Zoom and the question about whether or not you think there is life on Europa 37 percent said yes only 4% of said no and a sort of conservative 59% said I don't know which is fair enough but but I'm kind of in the yes camp myself along with our speakers I think so I did and thank you all very much for joining us tonight thank you again Jill and Cynthia and Simon for your moderation for Frank and Rebecca to Lee and jasmine and the team back at the Institute for putting all the technology together to make this happen everybody stay safe have a great rest of the week don't forget to say hi happy birthday to Frank Drake and we'll see you next time at the SETI Institute SETI talk series thanks again

Channel: SETI Institute

Views: 24,451

Keywords: SETI, astrobiology, europa, planetary exploration, life

Id: uPYq4IbtKgM

Length: 71min 49sec (4309 seconds)

Published: Fri May 22 2020