 So every month we highlight an activity that's related to the webinar topic. This month we're looking at some distant objects in our solar system and the activity that a lot of you already have in the Space Rocks outreach toolkit that came out a few years ago there's an activity called sorting the solar system so there's a deck of cards that looks something like this and inside these deck of cards there's each deck has two sets there's actually four sets in total so each deck has two sets this one I happen to have the yellow ones and so there's kind of some games you can play with participants or attendees at your outreach events one of the most popular is to have if you have a large group you could give one of these cards to each of the participants in your if you have 24 or 20 more 20 or more people if each person gets a card and then based on the information on the card based on the image that's on the card and so we have a few terrestrial objects but they might just be related to some of the objects that are in the solar system so there's some information on it and there's an image and the idea is that they go through and they attempt to organize themselves and classify themselves according to the properties of these objects alternatively if you have a table setup they can do this on the tabletop and create categories the really cool thing that we that we really like people to do is to take the series card out and so there's a card for series the one that was in the toolkit has an older image on it but we've recently updated those and that's on the website Dave's going to show that in just a minute and so we take this out and a lot of times what when I do this with large groups I like to give this to one person who observes everyone else doing their classifying and then give them this and say okay which group would you like to be a member of which group should you take series to and invariably everyone has sorted themselves and they have to choose between a couple of groups that make a whole lot of sense for them to join and so it really kind of points out that classifying solar system objects is not nearly as easy as what we are taught in school it's actually kind of messy and so hopefully we just might be able to hear a little bit about that here I think that Dave will put the link for the outreach toolkit and this activity from the night sky network website in the chat window and now for our featured program Dr. Alan Stern is a planetary scientist space program executive aerospace consultant and author he leads NASA's new horizons mission that successfully explored the Pluto system and is now exploring the Kuiper belt the farthest exploration in the history of humankind Dr. David Grinspoon is an astrobiologist award-winning science communicator and prize-winning author his newest book is chasing new horizons inside the epic first mission to Pluto co-authored with Alan Stern he's a senior scientist at the planetary science institute and adjunct professor of astrophysical and planetary science at the University of Colorado his research focuses on climate evolution of Earth like planets and potential conditions for life elsewhere in the universe please welcome Drs. Alan Stern and David Grinspoon. Hey guys it's great to see you. How's it going? Yep we can hear you great thanks. Excellent well this is really fun it's like we're all together even though we're dispersed across the continent. Yeah we're looking forward to this this evening would you like us to start or do you have some questions? Oh we're ready we're ready for you to go and then we'll walk you through for a Q&A at the end. That was our cue. We'll jump right in so what we're gonna do this evening is I'll tell you a little bit of the backstory what went into the exploration of Pluto I'm gonna put up some PowerPoint and sort of walk you through a little one-on-one on the mission but then Dave's gonna really tell you about the book and the plot line in the book and what it consists of and then we're gonna answer questions so we'll jump right in I'm gonna share my screen here we are and then I will launch the slides move the camera out of the way there we go okay so the title of my talk this evening is is about chasing new horizons it's to explore Pluto and there you see that wonderful open door to what we imagine Pluto might look like before we did the flyby in 2015 and we just completely underestimated that planet and its system of moons they have blown us away and so let me jump right in and show you how much new horizons change the game because this is the best picture image Pluto ever made before New Horizons and it's just a fuzzy blob now this was taken with the Hubble Space Telescope which is as good a tool as we have but because Pluto is only about the width of North America and it's three billion miles away this is the best we could do with modern technology from such a large distance and really it's because of those large distances that we have to send spacecraft out to these planets to explore them in detail you know take a look at a picture of the Earth like this now with this kind of imagery you can really do science you can tell that the Earth has continents and oceans complex weather a polar cap down there in the south in Antarctica and in fact by carefully analyzing this image just this one image at this kind of resolution you can learn a lot about our home planet and its atmosphere and a little bit even about its internal engine and its geology but if you smear if you repixelate this image of the earth to the best resolution of that Pluto image the best we had before New Horizons that's all you get that is a faithfully repixelated version of the image of the earth that you just saw and from this what could you tell about the earth very very little and I think we can drive that hope point home a little bit further you might think to yourself what are we looking at here and no telling what you're guessing but I bet you're not guessing what you're really looking at because at that resolution you really can't tell one type of object from another as illustrated by that pixelated version of the flag and the full resolution version so we go to the planets to explore them we have to see them up close in order to do that at the conclusion of the Voyager project that explored all the giant planets in the 1980s a group of us as young scientists wanted to see NASA go on and cover a little bit of unfinished business and explore Pluto which Voyager unfortunately couldn't explore and listed there on this slide are a whole series of attempts to get a mission to Pluto it stretched all the way across the 90s and as we describe in our book Chasing New Horizons there was a lot of complicated politics involved a lot of intrigue and it took a long time to make the case to raise the kind of money that it takes we had to overcome some management challenges some mismanagement challenges there were really no technical barriers it just took a long time it was 2001 before New Horizons came on the scene and actually became a mission that got off the drawing board and actually got built and a big part of that was convincing the planetary science community that going to Pluto was one of the most important things we could do with our limited budgets because we all have to share those budgets and there are many competing desires scientifically to study small bodies like comets and asteroids to go back to the giant planets and their fascinating systems of moons to go back to our own moon to study Mars in more depth and they're all jostling and competing for priority and only the very top most highly ranked science can be afforded because there are many times more ideas than there's money to go around for all those ideas and the winnowing is very steep it's not just the top 10 percent it's more like the top 5% that actually get funded so if you wonder what it was that got Pluto funded let me tell you what almost got us there and it was what we learned about Pluto from the earth fascinating Pluto and that system from telescopes back on the earth and even though our imagery even using the Hubble was blurry that top graph is a reflectant spectrum of the surface of Pluto made in the early 90s that showed us just how complicated Pluto's surface is it's dominated by molecular nitrogen ices but there are also dips in those spectra due to methane which is basically fuel that's scattered all around the surface and carbon monoxide a third ice and at Pluto's temperatures all three of those ices are mobile that's a complicated situation that's really outdoes not only the earth but even Mars and it's in its complexity the other figures here show some other aspects of what we were learning in the late 80s and the 90s about Pluto on the bottom left is a graph from what's called a stellar occultation that showed us that Pluto has an atmosphere and one with complicated vertical structure and of course that excited the atmospheric scientists when we discovered Pluto's large moon Sharon and understood that it was half the size of almost a tenth the mass of Pluto it became clear that the origin mechanism for the Pluto Sharon binary planet as we call it is very similar to the giant impact that form the earth moon system in fact it's ironic but nowhere else in the solar system from the earth all the way out to where Pluto is nowhere in between did we find another example to study by analogy how the earth moon system was formed but we knew that at Pluto we could we could do that because it's such a similar formation that's and then on the right is a cutaway drawing of what we came to understand in the 90s composition of Pluto you know we found all these ices on its surface and we expected an icy planet through and through but when we understood its mass and its size it could get its density became clear that you can't judge that book by its cover Pluto is ice covered on the outside but inside it's about 70% rock by mass so it's really a rocky planet with an icy shell and that was highly surprising not expected for something in the deep outer solar system and all these attributes from Pluto's giant satellite to its atmosphere to its interior it's complicated surface composition all those were strongly indicating this was a place that was going to be worthwhile exploration target but what really made the difference was a change in our view of the map of our solar system the architecture if you will this is the old view it's probably something you saw like I did in grade school textbooks it's kind of a map a 20th century era map of the solar system shows the Sun in the middle the four rocky planets orbiting in those tight orbits down by the Sun Mercury Venus Earth and Mars a little asteroid belt and then on a much expanded scale the orbits of the four gargantuan giant planets Jupiter Saturn Uranus and Neptune in order that way tends to hundreds of times what the earth the largest of the terrestrial planets ways and then orbiting beyond both that inner zone with the rocky planets where the earth orbits and the realm of the giant planets was Pluto which when it was discovered in 1930 immediately stood out as not fitting either pattern didn't look like a giant planet didn't look like a terrestrial planet orbited much further out much more egg-shaped orbit that really left our 20th century view as Pluto's the misfit of the solar system but as it turned out eventually as technology got better the telescopes the CCD detectors the computer technology to detect faint moving targets we eventually found that that view was completely myopic that the real view of the solar system is more like what we're gonna show right now and I have to start a little video we're looking down on the solar system and there you see dots appearing out there where Pluto the big dot is orbiting these are actual discoveries of other objects that orbit with Pluto they're much smaller than Pluto generally but every now and then you'll see a big dot this is the Kuiper belt it's the third zone of our solar system and it's the biggest discovery about the architecture of our solar system in any of our lifetimes it revolutionized what we know and I want to stop the video and say that it wasn't just that the discovery of the Kuiper belt provided context for Pluto and redrew the map of the solar system the most interesting thing was we found the Kuiper belt is littered with small planets of which Pluto turns out to be the largest and the brightest and the one that we knew the most about but there are plenty more and you see some of their names like Sedna and how may I mock you mock a eras and Ixion and Varuna and so forth and it was this discovery that really rocketed the priority to go out and explore Pluto up to the very top of the list because we realized and all the way up to the National Academy of Sciences that there was this third zone to the solar system with a third class of planets the so-called dwarf planets that had never been explored and Pluto represented the archetype of that whole class and so by going to Pluto you could begin the exploration of this new class of planets in this new region of the solar system and in fact just to put that in perspective up here along the top are all the planets of the solar system from Jupiter through the four giant planets to earth and Venus all ordered in size all the way down to the tiniest skies and you know Pluto which we had thought had been to be the smallest planet actually turns out to be right here where I'm pointing the middle of the distribution just amazing who knew the solar system was so good at making planets and that did cause the National Academy of Sciences in the early 2000s and prioritizing missions in a process we call the Decadal Survey to rank the exploration of Pluto in the Kuiper Belt number one on the runway for priority and that unleashed the funding and as we tell the story in Chasing New Horizons NASA put on a competition and let teams form to propose their own mission I led the New Horizons team of course and this is the cover of our proposal here in the lower right that proposal is about well even thicker than that about the thickness of a an old New York City phone book with technical designs and scientific case and scientific instrument designs plans for how we would carry out the entire project and other teams formed and wrote their own proposals and then NASA had those proposals reviewed and competed and ultimately selected New Horizons as as the best and off we went to the races that was in late 2001 that we were selected and for the next four years as New Horizons built up to eventually be a team of over 2,500 men and women we were in a real horse race to build outer planet spacecraft in about half the time it had ever been done before because we had to make the one and only remaining Jupiter gravity assist launch window of the 2000 so launch window that lasted only three weeks long in January of 2006 and so this team was working nights was working weekends year after year to design and build and then test that spacecraft racing really against the odds to make that launch window and at the same time we were very heavily challenged by the fact that the budget that we accepted from NASA to do this was only about 20% the size of the Voyager budget so we had to make some pretty big innovations some pretty dramatic breakthroughs and how you do low-cost outer planet exploration but my institution the Southwest Research Institute and our partners at the Johns Hopkins applied physics lab universities around the country ball aerospace and others signed up for that and we actually pulled it off and this is the spacecraft that we built that's New Horizons down in Florida shortly before its launch at the Cape you can see the dish antenna on top my cursor is pointing to the nuclear power battery their so-called radio isotope thermoelectric generator that powers all the spacecraft to go far from the Sun where sunlight isn't strong enough you can see how small the spacecraft is next to these people you know Voyager is the size of a houseboat by comparison and inside this little shell here are all the guidance systems command and control communication systems the propulsion system everything we need for the journey and then in our book we described the whole design process is great for nerds chapter about how we made those innovations to save money and to invent things like how we hibernate a spacecraft as it flies across the solar system so we could have much smaller flight control teams we also talk about the giant advances in scientific instrumentation the quantum leaps in our ability to send much smaller cameras with much higher capability and the same for spectrometers and other instruments on board and and we did make that launch window we finally got to our ride this giant skyscraper sized Atlas 5 that was a customized completely tricked out to make this the fastest spacecraft ever launched so that we could cross the solar system in record time we met the launch vehicle down in Florida in late 2005 with our spacecraft ready to go and right at the end just a few days before launch we fueled that nuclear power generator that I'm pointing at with its radioactive plutonium sealed the cap and because it was radioactive they wanted to put the hatch of course on the on a nose cone and they gave us a chance to have a few of us on the project have our picture taken and as I tell in the book this is was my choice to go last in that list because I knew that that would be the last picture ever taken of New Horizons just minutes after this picture was taken that hatch was closed there in the nose cone that New Horizons sat in the darkness until we launched it six days later on the 19th of January 2006 and that launch was just incredible that big rocket 225 feet tall went supersonic in half a minute put us in Earth orbit in eight minutes and actually in under an hour New Horizons was off the launch vehicle traveling so fast that it crossed the orbit of the moon in only nine hours compare that to Apollo missions it took three days and we were often on our way and there was some drama around the launch there were two launch attempts that didn't succeed before we had the one that did succeed we tell that whole story too and then we tell the story of our journey across the solar system first to Jupiter for that gravity assist and for the only thing that we pass along the way so our only flight test to make sure that things would work at Pluto and then off across a long eight-year journey from early 2007 until July of 2015 towards that that ring of material called a diaper belt where Pluto is to intercept Pluto's orbit right as it crossed the plane of the solar system with our red trajectory of our spacecraft coming out you know during those eight years our team was extremely busy and only 50 of us or so whereas Voyager had 450 people to do a similar job and there's a wonderful chapter called battle plan Pluto where we really tell the inside story of how you plan a one-shot fly by make your backup plans and how you guarantee that you can dodge hazards if you just discover them at the last minute how you train your team how you prepare for every aspect of what we called show time and our encounter with Jupiter was completely successful these are images of Jupiter and its volcanic moon IO made by New Horizons as we pass by and then we were off on that long journey I just spoke about but I'll fast forward here in the interest of time and turn to the fly by which began when we woke the spacecraft up from hibernation in December of 2014 and began in earnest once we prepared the spacecraft with navigation and hazard avoidance imagery in early 2015 heading for that culmination in the summer on the Bastille day on the 14th of July 2015 when New Horizons swept down inside the orbits of all of Pluto's moons down very close to Pluto and used its cameras and onboard spectrometers to study to the surface its geology all five of its moons to map its surface composition assay its atmospheric pressure and temperature and atmospheric composition and where the result was just fabulous these are pictures of a couple of people that are in the book Glenn Fountain on the left who's our was our project manager during the spacecraft build and during the flight across the solar system and there's a view with one of our flight controllers in our homebrew mission control at Johns Hopkins applied physics lab and then we found ourselves on close approach to Pluto to the only new planet explored since the Voyager days a generation before and this is kind of a family portrait with Pluto in the lower right its giant Texas sized moon Sharon there just above into the left and two of its four small moons Nixon Hydra shown here this this image was made when we were literally still millions of miles away but we did much better became because we came so much closer this is a nice montage of global mosaics of Pluto and its big moon and you can see how different the two objects are they've evolved completely differently Pluto's bright and colorful with an atmosphere and very highly varied surface geology Sharon is a lot like the icy satellites of the giant plants covered in water ice and very ancient surface here's Sharon up close and you can see how heavily battered that surfaces and from those crater counts we can age date that surface at four billion years old but we also see really interesting features on top of those craters imprinted on top like the red polar cap that does unlike anything seen anywhere else in the solar system and that giant scar across the equator that I'm pointing out with the cursor which is what the geologist called it equatorial tectonic belt but what it really is is is the result of the freezing of all the water inside of Sharon and as the water froze it expanded of course and created stress patterns that ultimately created this canyon system that dwarfs the Grand Canyon 1500 kilometers long 10 times as deep as the Grand Canyon the largest canyon system seen anywhere in the outer solar system well that's Sharon but I'll tell you it doesn't compare next to Pluto because Pluto turned out to be far beyond our wildest dreams in terms of its complexity and geologic activity I think if you look in the upper right you see that iconic image of Pluto with the heart on its surface that heart is a giant nitrogen glacier that's larger than the states of Texas and Oklahoma combined and here you see it in the main image in close-up where we've wrapped those images on a sphere so it gives you the appearance that you're actually standing above planet Pluto and looking down and you can see that those crater fields in the periphery of the image the older terrains don't look anything like the glacier the glacier doesn't have any craters on it whatsoever even in our highest resolution images we can't find any craters meaning that that surface was born yesterday geologically and that really shook up planetary science to think that a small planet the size of Pluto could be so active as to create a million square kilometers of glacial terrain so recently that not a single crater appears was just jaw-dropping but there was a lot more that we found we found that that glacier is actually flowing we found currents in the glacier particularly where it abuts the mountains we found evidence of avalanches from the mountains above here that you see the yellow and pinkish and green drains that are high altitude more than 20,000 feet above the glacier where material is poured out in avalanches down these shoots into the glacier and we found that Pluto's atmosphere is fascinating with these concentric haze layers and the surface is much more rugged than many expected because the water ice that makes up Pluto's crust is a strong enough material to support towering mountains and not just mountains but mountains with snow caps like these these mountains are the size of the Rockies in Colorado where I live and the snow caps look very similar to the snow caps out my window in Colorado they're bright and white and cresting the top of all those mountains but they're not made of water ice those snow caps were fingerprinted spectroscopically by New Horizons and they're created by methane light hydrocarbon a fuel that we use in kitchens all around the earth it literally snows fuel on Pluto and that's one of the reasons I like to call it a sci-fi planet but there was more we found evidence for ice volcanoes like this one that we call Wright Mons which is the size of Mauna Loa in Hawaii just as tall and just as wide it's massive structure and it by the way also doesn't have any craters on its flanks meaning it must be very young as well that Pluto's active in many different ways in fact it even has what we believe are frozen lakes on its surface like this one which we know from stereo imaging is in a hanging valley and you can see the shoreline around this lake which is about 20 miles stem the stern and made of nitrogen again but the interesting thing about this is you can't have liquids on Pluto's surface today the pressure in the atmosphere is too low and the temperature is too low you can only have ices so the presence of this feature is a strong clue like others that Pluto used to have liquids standing or running on its surface and even beyond the volcanoes and the glaciers and the avalanches and the atmosphere and the frozen lakes we found strong evidence that Pluto has a global liquid water ocean in its interior something that has really turned heads because it could mean that Pluto like Europa and other worlds with oceans on the interior could be in a boat for life and it raises the priority for doing things like going back to Pluto with an orbiter to study it more detail and learn more about that ocean well uh i'm going to close by saying this is our favorite my favorite image of the entire flyby it's true color looking back as we pass through Pluto's shadow looking back at the planet silhouetting being uh silhouetting the sun which is backlighting the atmosphere and as we tell in Chasing New Horizons the story of the 26 years between when a group of young scientists with a dream started to figure out how you could convince NASA and the scientific community that we should go back deep to the frontier of our solar system and explore the Pluto system and how that came to be and all the trials and tribulations and competitions and setbacks and victories and the flight across the solar system and the exploration of Pluto all of that 26 years for me is culminated in this single image because i worked 26 years like a lot of us did to have a picture taken from the far side of Pluto and this is it and i think it's a beautiful image and i think it the it nicely encapsulates the accomplishment of what we did and i think with that i'm going to turn it over to Dave to talk about the Chasing New Horizons and the human story. All right um let's see can you guys hear me? I am unmuted um good evening well uh that was awesome Alan that that's a real encapsulation of of a lot of what what is in the book um but but let me uh talk a little bit more about the experience of writing the book and and about how uh how the book came together and how it's structured and what's in it um for me the uh the story that Alan just summarized uh nicely of of New Horizons is uh really one of the most incredible exploration stories of our time and so the experience of being able to write Chasing New Horizons with Alan uh was really just um such a privilege for me it's it's a story that i've treasured for a long time um that i've known about i've followed uh i've been uh somewhat involved myself in terms of serving on committees that at times were pivotal but mostly i was involved just a member of the planetary science community and as a fan of this mission um and and so i i've watched this unfold really over decades and uh so many times i remember thinking that i cannot believe um what these guys are going through i cannot believe this story if you know someday that some but someday somebody's going to write a book about this uh a good book you know especially if they succeed which you know times when i thought that it seemed like a long shot you know uh but so now to remember feeling that way but to have actually seen the mission through and seen it succeed and then have to have had the opportunity to write the story of this mission with Alan Stern who lived it um has really been a privilege and um when Alan approached me about working on this book together i was like are you kidding you know of course yes let's do this because uh because i because i know it's a great story at the same time i knew it was going to be a big challenge to um to encapsulate all this in you know in a book that's only um you know uh 269 pages because there's so much to tell and in fact when we originally wrote this book there was a lot more and we had to winnow it down and you know what's left is like the really good stuff but uh basically this came about through a long series of conversations um Alan and i um started off by really once we agreed to work on this book together uh and you know came up with a very rough outline which of course evolves as you're working on it what we did was we spoke every saturday for like a year and a half on the phone and it started off Alan had a series of stories a list of stories that he wanted to tell me and then that of course in the telling and in the questions i asked him led to more stories and we went through them and and and um then figured out how they would all fit into the structure of of telling the story of new horizons and in the process also of telling me these stories a lot of other characters came out and he would mention somebody i'd be like i got a follow-up on that and that led to a list of a whole lot of other participants that i interviewed scientists engineers people at nasa who are involved in the political drama and one thing that was fun was hearing the same story from multiple people and then you know trying to synthesize the the the events and pulling in multiple voices and you'll see many places in in chasing new horizons with that we we cut away from the narrative to just let people talk in their own voices so there are places where you hear Alan's voice in the first person but then also people like Alice Bowman the mission operations manager who is absolutely key and is you know a hero of the mission and some of the other scientists and and you'll hear uh the stories narrated in their voices about what the experience was like and and you know roughly it comes down to sort of three three uber stories which then are all told through the personal experience of the people who who experience it and those three stories are number one is the sort of the politics that behind the scenes how it works how a mission really happens how it goes from this dream as Alan said a bunch of young dreamers who didn't fully know how to make this happen but you know first sat in a room together and plotted you know we want to send a mission to Pluto how are we going to make this happen and formulated a plan and then all the struggles they went through um you know ridiculous struggles for years of dead ends and doors slammed in their faces and having to you know go to plan b and plan c and plan d prime but you know eventually uh you know not giving up and um making it happen but then wound through that the science comes out because the science waves into the politics in a lot of ways as Alan described a lot of discoveries happened uh during this struggle that made the case for Pluto more compelling so one of the objections at first was well Pluto's not that interesting it's just an oddball on the on the outer edge of the solar system why would you want to send a mission there it's so far away and would cost so much but as this effort was under was underway to try to make the mission happen several discoveries happened which made it more compelling the discovery of of Pluto's moon Sharon the discovery of the methane on the surface of Pluto the the discovery of the Kuiper Belt most important of all as Alan mentioned that it's this whole zone of the solar system so the story got more and more interesting as they marshaled support and that really became key in getting the scientific community the planetary science community ultimately to line up behind this mission so there's that whole story of marshaling the support and just getting approval and getting funded and getting green lit and the drama that goes into that and then once they have a mission they have to do the mission and you know that's really intense because there's a ticking clock they have to meet the launch window they have to meet the budget and so then there's all the how the sausage is made of how does the mission really come together what are the decisions and how do the teams organize and who does what and how the heck do you make this all happen within this very tight time budget and I think we tell that story in a way that's never been told before so anybody that's interested in space exploration who wants to know how a mission really comes together I think there's a lot for you in this book and then of course finally there's the drama of the launch and the trip across the whole solar system which you know is again there's a lot of untold stories there you know some people think well once you launch you just you're just waiting for nine years and you know aren't you bored but you know no there's it's very intense the the work that goes in and you know the different phases getting to jupiter testing out the spacecraft at jupiter the data that you get from that fly by but mostly you're you know it's a trial run for the spacecraft and then even though the long ride to Pluto there's a lot of really intense you know just the planning that's going on whoa is something happening on my screen here no we're okay i'm still there i just got a glitch there for a second the the amount of just precision planning the choreography of the spacecraft that has to be constructed and has to work flawlessly the first time and then of course there's a couple hairy moments when things do not go as planned and there's uh there's especially one major glitch that happens at the worst possible moment where the spacecraft goes offline there's huge crisis they're almost at Pluto um the team is tested as never before Alice Bowman who i met who i mentioned before the mission operations manager she and her team of engineers um saved the day in um you know literally it's a cliffhanger and just at the last possible moment they get the spacecraft fast back online and if it hadn't happened you know within a space of a few hours literally the the flyby would have been lost and so that's you know more intense drama than you know than anybody would wish but it makes a good story and you know and then and then the flyby itself the the encounter of Pluto of course we tell the technical story and the scientific story but the emotional story the experience of the participants people in their own words telling what it was like to be there the surreal sense of this moment you've lived for you know your whole life your whole career unfolding so quickly um and uh so dramatically and so powerfully and then and then the payoff of course the images Alan showed you a few of them in the book we've got a selection of really high quality nicely reproduced images of Pluto and the moons and of the spacecraft and and candid shots of the team members and the people that we tell you about so that's all there and then you know the payoff it the scientific payoff and the the conceptual payoff of sort of rewriting what we know about how planets work about how our solar system is constructed about the the potential for small planets to exhibit this you know just incredible diversity and lively behavior you know that is something that we're going to be incorporating into the way we think about planets for a long time you know so so that was you know there were a lot of great surprises and you know finally we end on talking about the public response and you know what what we describe is in a way that the the thing that surprised us the most or the thing the thing that we learned that maybe we weren't expecting we end by talking about just the way that this that the new knowledge and the exploration of Pluto inspired people and the effect that it had on people it was so you know so moving you know that people telling Alan stories and even during our book tour that we just did people telling us stories from around the world of their experience of the Pluto flyby you know and it really was this global event now that we're all connected as as we can see now because we're all talking to each other from different parts of the the country in real time but people were telling us stories from you know we met this guy who was in a bunker in Kabul during the the flyby hit and refresh to see the new pictures and you know just the the outpouring of global interest and inspiration at a time when we all need it let's face it you know that that inspiration that sense of that our country can do great things and that the human race can do great things and that the exploration of new places is is not over you know that that sort of there's a feel-good aspect to this story that is is genuine and that people are really responding to so you know I feel really good about that that we were able to take all of that and you know our initial manuscript of course was much longer than our final manuscript because there really is a lot there and went to it down to a really i think crisp and and compelling story that people are telling us that they're they're finding really inspiring and you know people keep telling us this ought to be a movie and we're like you know okay you know who's going to play Alan but but i mean the point is that there there's genuine drama and genuine it's it's kind of a thriller you know of course there's science but it's not ultimately a book about you know it's certainly not a textbook it's a book about the human drama and what it takes to to fixate on on an idea not let go and ultimately explore in you know go places and go farther than anyone's ever gone before and you know really what is behind that in terms of the human effort and the technical ingenuity and you know that that that's the story we tell and and the way it affected people and i i feel pretty good about the fact that we i think we pulled it off so anyway that's chasing new horizons i i could keep going but i won't because we want to now take some questions i think and we certainly have a lot of questions that have come in and so and i i really like what you said there david i know a lot of times when i'm working with teachers and doing these solar system classification activities and and we think about the demotion of pluto and we talk about whether that was an emotional or a rational reaction that they're having to that and invariably they'll all say oh yeah it's an emotional reaction that you know might you know upset at this or whatever with the with the whole process and we have this emotional attachment to pluto for some reason that we don't have for other planets you know sometimes maybe not even for our own planet so it's interesting yeah by the way one one part of the story that i forgot to mention just now uh this relevant to that is that we do tell the story of clad tombow and his discovery of pluto and the fact that this is all you know that front that it wasn't that long ago 1930 there are people still alive and that this whole sort of generational arc from the discovery of pluto and the beginning of planetary exploration and the you know the attachment that people have to pluto as you mentioned is really remarkable and that's something we keep discovering again and again and you know i to some degree i understand it it's an underdog it's an outlier it's an oddball you know people maybe identify with that but there's also there's some mysterious um i still don't understand it but kids love pluto and people love pluto it's for some reason it's the planet that people love you know if i could just jump in for a minute the the whole story of uh uh how we view and many maybe a vast majority of planetary scientists view that whole iu decision is about one percent of the book we wrote three or four pages about that because you have to cover it but uh the brilliance of the book is really the architecture of the story that david put together and he's such a fine writer and he's done so many award-winning books and you know you could have written just the story in order but he actually starts in 2015 with the spacecraft on approach and having this near-death experience he talked about and then uh you know even though maybe the cover is a spoiler you know you know we got the pluto um he leaves you hanging uh just a dozen pages into the book you this is crisis and it develops and it's horrific and it's proportions the spacecraft is hurtling towards pluto with no instructions for how to carry out the flyby and the minutes are ticking away and then david takes you back to the start and works through all the politics and all the challenges and a flight across the solar system before you find out how it turned out and it's just brilliantly written i can't tell you how many people have come up to me and said you know uh like david said it ought to be a movie you know you wrote a novel um except it really happened you know it was a michael creighton novel that really happened and uh that's david's uh david's uh skill set showing off right there i think i can see uh tom hanks playing you ellen so it's uh okay we've got a few questions on a journey it doesn't work out well yeah that's true that's true spacecraft to blow up or airplanes to crash whatever oh that's true that's true uh well we've got a few questions here and i'm going to try to we i'm going to have to jump back and forth a little bit to try to combine so some marking out so that i i have our i want to add on to them from someone else earlier ask how far is the vessel expected to travel before it no longer receives signals whereas no further energy to accomplish those tests and very early on curts asked about the redirect in terms of the fuel and so and then instruments on board to study interstellar stellar space yeah the prolonged mission you know how are you how are you doing that as far as fuel and instrumentation well you know uh from the beginning when nasa called for this mission they required all the teams that competed to design a spacecraft that could go way beyond pluto could communicate much further out it could last much longer and it could go on exploring across the quicker belt and that's what we're doing right now i don't know if you can see the mission sticker for our first extended mission which is uh now reaching a tide point because in six months we're at the end of june at the end of december we're going to explore another object a billion miles it's easy to say but hard to fathom a billion miles further than pluto uh one of the building blocks in these small planets like pluto which we've nicknamed ultimate tully and uh we're real excited because we are right on approach for that final approach for that now but the spacecraft has the power uh on board from its nuclear battery to go on for decades it should operate into the 2030s before the power levels drop to where we can't really operate it and across that next 15 or 20 years spacecraft will travel to a distance about three times as far away as pluto almost a hundred times as far from the sun as the earth is and we expect to look for more flyby targets we expect to study dozens of kuiper belt objects and the environment out there and the spacecraft is completely healthy none of the backup systems are being used and we expect to to be out exploring the kuiper belt for a long time. Stuart has an interesting question back to uh pluto itself any thoughts on the idea that what appears as geological activity might be pluto responding to the variation in solar heating that receives um due to its uh you know highly elliptical orbit? well that's a clever idea but the arithmetic doesn't work out pluto is very far from the sun even at its closest approach to the sun each orbit the sunlight is only one one thousandth as powerful as it is here on the earth so it's very feeble and yeah it goes almost twice that far out so now it's down another factor of four times less but you know it's like feeble and ultra feeble and the difference is so small in terms of the numbers that it can't it can't even power the atmosphere barely power the atmosphere it's not about to be enough energy budget to power geology that can lift mountain ranges or create avalanches and you know vast volcanoes so um it's a clever idea but it just doesn't work by the numbers there must be something going on in the interior of pluto that creates this this very active geology that rivals the earth and mars and we don't admit it we don't understand it people have a lot of ideas we don't know if any of them are right i mean it must be it's certainly true that that some of those long-term cycles of climate and season on pluto add to the complexity and the interest of what's going on on the surface you know the interesting frosting on the cake for sure but the cake itself i mean you don't make 14 000 foot mountains by you know by interesting weather there's something going on in the interior that's doing that geology and uh this kind of uh there might be a follow-up here mark asked or maybe you already answered this mark asked do any other kbos have atmospheres and then he also asked about possible energy sources for generating those in any new surface features well there are objects uh you know other planets in the quiper belt that have the same volatiles on their surface the scent the nitrogen for example and the methane uh and even the carbon monoxide are seen on the surfaces of other small planets out there but so far we haven't detected an atmosphere anywhere but in pluto and uh you know i hope to see in my lifetime uh missions to go exploring some of those other worlds that are out there and where we can really get up close and i showed why we need to get up close because we can't study them very well from afar we might find that they have atmospheres now or atmospheres in the past currently pluto is the only one with an atmosphere and interestingly enough an atmosphere of blue skies see so Lloyd asked a question and i know a couple years ago mike brown announced a possible other planet out there is there any instrumentation on new horizons to potentially look for evidence of this additional large planet it would be great if there were um the telescopes on new horizons are pretty small the largest one is about this diameter and you can do better from the earth not only because we have vastly larger telescopes uh but also because our data transmission rates are pretty low and the amount of data that you have to take uh to search the entire sky to maybe find uh more distant planets is something we really can't do from new horizons it's better to do it from big ground-based observatories so brian asked uh based on what we've learned from new horizons are there any new questions that have come up that would justify another mission to the kiter belt or maybe we can even extend that and say what real well there are lots of surprises but what new questions are you most interested in investigating well we're both scientists so we ought to both take a crack at that one you want to go first day well yeah i mean in general i would say that new horizons has vastly raised the scientific profile of the kuiper belt as a um as a set of targets for future missions um because um you know i mean there was a wide wide spectrum of how interesting Pluto could have been and you know at a scale of one to ten it's you know it's like a 275 as far as how interesting it is it's just way off the scale and um you know so the real i mean to me the burning question is do you send the next mission back to Pluto or do you go elsewhere in the kuiper belt but it's like you know the kuiper belt itself is is such a rich place uh that we know now that you know that a small planet can be as active and as interesting a small planet that far from the sun new horizons has raised so many more questions than it's answered now i mean i just want i want to see what's on the other side of Pluto you know for one thing and that's and you want to do long-term investigations and deeper investigations and and follow up on you know is there really an ocean and and what are its characteristics that's just on Pluto alone and then yeah there are all these other interesting objects out there so so absolutely we're going to need new missions and i think the case for that is going to be much easier to make now than it would have been you know a few years ago and i have no doubt that there'll be more missions to the kuiper belt we're coming up on a new decade old survey and new horizons showed how scientifically game-changing Pluto is uh it deserves an orbiter we really want to understand that ocean the geology as Dave said map the rest of the planet get up close to the moons that we couldn't do there's so much to learn at Pluto uh that uh there's no question it's just too hard to figure out with one mission on a simple flyby but on the other side of the equation is the fact that when we look at the planets of the kuiper belt we see there is diverse as the terrestrial planets there are places out there that are as different from Pluto as venuses from earth or mercury for that matter there's some that have inert surfaces the some that have active surfaces and some that have a bunch of moons some that have no moons and some that are pink and some that are blue and you know in every respect it's a diverse population and it deserves a survey a suite of missions that go out there and look at these diverse planets of the kuiper belt and so i think the big choice is between looking at the diversity or going back to Pluto and studying in depth and i don't know how that's going to turn out in the decade old survey there forces marshaling on both sides and uh one or the other will end up getting the next mission of the kuiper belt that's part of the adventure okay Gordon asks if there's any way to know if other planetary systems have include Pluto-like objects and right now our technology isn't capable of detecting these although we do have next month we're going to hear from Tabitha Boyajian with a Tabistar and so she might have some insight under that question actually you know we think Pluto-like planets are common but we don't have actual evidence of that except in our solar system we know that they're the most populous class of planets the dwarf planets the kuiper belt but we do know that kuiper belts are common even though we don't know what kinds of planets are in those kuiper belts we can see them as dust disks on the outer fringes of other solar systems and they appear to be a very common construct so there are going to be kuiper belts around many if not most solar systems okay i want to do a quick time check we are at the top of the hour and we promise that we'd be done by seven but we have a lot of questions are you willing to hang in there for just a few more questions for a few okay um okay so uh William asks um if you had doubled the budget of the new horizons mission how much faster could you have gotten this done and what would you have done to improve the mission well that's easy i think we wouldn't have done it any faster if we had twice the money we would have sent two spacecraft and we would have covered the far side of Pluto that Dave was talking about so frustrating that we see in low resolution images but we just weren't able to fly by up close uh i'm sure that that's what we'd have done if we had twice the money uh but we didn't have the money to afford what voyager could afford which was two spacecraft and so we sent one and we rolled the dice and it it turned out very well at work and uh Pluto certainly performed scientifically and the combination uh was a dream come true for all of us who worked on this project a number of people are also asking if the results of this mission are going to result in some sort of reevaluation of the status of Pluto as a planet or a dwarf planet if there's going to be some voting at iau about its status any any potential changes well we should want to try to explain what our planets we won't planetary science just to do that because we see what bs resulted when they uh when the astronomers did it now bs i should clarify as an acronym for bad science David you're trying to do it it's it's funny because uh you know i think neither Alan or i is is really advocating for the iau to take another vote on this uh you know maybe they will at some point it's clear that a lot of people recognize that their uh definition is inadequate i mean for one thing it doesn't even recognize the exoplanets it talks about uh a planet having to orbit the sun and you know there's a lot there's a lot of problems with it but what we notice is that planetary scientists are using uh the word planet in a way that makes sense to us when we go to meetings people uh refer to Pluto as a planet they refer to Titan as a planet you know because we're talking about the characteristics of these objects and uh we do comparative planetology and you know these objects have we compare mountains on on Pluto and mountains on Titan and mountains on earth and you know for planetary scientists there's sort of a natural use of that that word that is uh is the usage that's happening and so a lot of the professionals in our field are you know they just kind of ignore the iau ruling you know they're not the boss of us but also the science doesn't work by voting we don't take votes on anything in science we don't vote on whether the periodic table is right we don't take votes on the theory of durability or human evolution or anything else and voting is a is a really bad practice for science it gives the impression that things are arbitrary that uh uh you know by uh by ad campaign or something that you can sway a vote it's not enough science works it works one scientist at a time making up their minds until a consensus is reached and what David's telling you is in planetary science there is a consensus the experts the people who really do this for a living not astronomers but planetary scientists called these bodies planets because that's what they are and they voted with their feet and with their mouth and with their mind and uh all of you out there are now deputized and authorized to call the dwarf planets planets just as planetary scientists do all right well we're going to go last question here and i like this one uh Gordon says if we stood on Pluto on the side facing the sun and i think that that would be a really fascinating you know thing for any of us to do if we were to stand on Pluto on the side facing the sun how bright or dark would it appear compared to doing the same thing on earth well i'll take a crack at it um we've actually calculated that uh you know uh and before we got new horizons to Pluto as a public engagement activity we uh we did the calculation and then we put it out there and said you know it's about as bright as a nice clear day on earth 20 minutes after sunset so go outside 20 minutes after sunset and we'll call that Pluto time and take a picture and it turns out thousands even tens of thousands of people all around the world are taking pictures in the dusky twilight showing scenes in europe and in africa and across north america and you know you can read a book by that kind of light and you can see your friends faces and the colors of their clothes it's a maddeningly dim light compared to what we're used to at high noon on the earth but it's enough light to see to walk around to explore the surface of Pluto and uh you can go out now even though we've done the fly by at Pluto 20 minutes after sunset that's Pluto time okay yeah i was i was actually really uh surprised by that and when you look at those pictures that people take the Pluto time there's plenty of light you know and it's partly because the human eye has such an amazing dynamic range but the fact is yeah if you were on Pluto uh at noon looking around uh you'd be able to see just fine wow well i think that that would be an aspiration that hopefully someday some humans will be out there and be able to have just that experience so thank you very much dr stern and grinspoon this has been a most fascinating you know talk and i'm certainly looking forward to uh reading the book and and i think that we've got uh many of our members have read it they've indicated that they've really enjoyed that and so thank you again for joining us from uh you know ellen anyway from somewhere on his travels so thank you very much for taking time out to join us thank you brian and thank you day