Planetary Radio: Space Exploration, Astronomy and Science - Countdown to Jupiter

Episode Date: June 28, 2016

Juno will enter Jupiter orbit on July 4th. Mat Kaplan talks with the mission’s Principal Investigator, Scott Bolton at the Jet Propulsion Laboratory. Bill Nye helps prepare us for this exciting encounter and the science that will follow.Learn more about your ad choices. Visit megaphone.fm/adchoicesSee omnystudio.com/listener for privacy information.See omnystudio.com/listener for privacy information.

Counting down to Jupiter, this week on Planetary Radio. Welcome, I'm Matt Kaplan of the Planetary Society, with more of the human adventure in our solar system and beyond. And yes, that's the first time we've opened with that line. Another mission leader joins us this week as he prepares for the arrival of his spacecraft at the King of Planets. We'll talk with Principal Investigator Scott Bolton about Juno and Jupiter. Bill Nye prepares us for that conversation, as only the science guy can, and we'll check in with Director of Space Policy Casey Dreyer at Politicon. Senior Editor Emily Lakdawalla gets us rolling with her report about

a mission to one of the nearest yet most mysterious locations in our solar neighborhood. Emily, you've now written about this next mission that China is planning to land on the moon and rove around a little bit. Tell us about it. Well, we're talking about Chang'e 4, which is based on the backup spacecraft of the mission that became Chang'e 3. They've done this with their previous missions. Basically, they build two spacecraft, they launch one, and if the first one achieves its goals, which both Chang'e 1 and Chang'e 3 did, then they launch the backup one as a slightly more ambitious mission. And that's what's happening with Chang'e 4. Is this one going to that mysterious, still somewhat mysterious side of the moon that we can't see? Yes, this one is going to be the world's very first far side lunar lander, which is pretty amazing. And in order to make that work, of course, because the moon keeps that side of it facing away from Earth at all times, there isn't an easy way to communicate with the spacecraft that's back there. spacecraft that's back there. So they're actually going to have to launch an orbiter mission,

a mission that will journey to the Earth-Moon L2 point, kind of this gravitational balance point along the far side of the moon, to serve as a communications relay. And then six months later, they're going to launch the Chang'e 4 lander and rover. Making this mission even more interesting. All right, what is it about the far side, other than that we can't see it from down here, that makes it so special? Well, there's two main reasons to put a mission there. One is the one that the Chinese seem to be pursuing, which is the fact that you can use the great bulk of the moon, which is planet-sized and planet-shaped, to shield your spacecraft from the radio emissions of Earth. So they're going to be doing some radio astronomy back there on the far side of the moon. The other reason is that the far side has this feature called the South Pole Aitken Basin. It's the largest impact basin on the moon

stretching from the South Pole in the south to the Aitken Crater, which is a bit below the equator. If you look at the far side of the moon, it's got this different color to it. It's clearly there's different mineralogy there. It's the oldest impact feature on the moon. It's probably the deepest. They think it may have even dredged up mantle material. So being able to study its chemistry would really tell you a lot about the early history of the moon and the Earth. Yeah, but is this spacecraft going to be able to do the chemistry work that a lot of scientists would like to see?

That's the thing I'm not so sure about. So the spacecraft has quite an ambitious complement of instruments, but one of the things that's not on this mission is any kind of instrument that can do elemental chemistry. They do have something that can do near-infrared spectroscopy, which is sort of one part of being able to identify minerals, but it's really hard to be sure what minerals you're looking at without some information about the elements present. They took off the APXS, the Alpha Particle X-ray Spectrometer, because Chang'e 4's rover will have

no arm. And so that makes it kind of questionable whether they're going to be able to get the geochemistry results that people really want to see, that geologists really want to see from the far side of the moon. All right, still some exciting plans, Emily. To the moon. Thanks so much. Shashe. Shashe, man. She is Emily Lakdawalla, our senior editor and the planetary evangelist for the Planetary Society and a contributing editor to Sky and Telescope magazine. Up next is the CEO of the Planetary Society, Bill Nye the Science Guy. Bill, as you know, we're going to be talking to the head of the Juno mission, Scott Bolton, in just moments. I know from talking to you that you're excited about this mission, too.

Oh, man, I was really invested in this mission years ago. I went to the launch. Now it's finally going to go around Jupiter. I mean, understand, everybody, there's some cool things about the spacecraft. First of all, it got a slingshot from our own Earth. The orbit was so carefully figured out. It's all solar power. There's no plutonium, none of the controversy that's often associated with trying to get a piece of plutonium on a rocket. It's going to do this amazing thing to try to understand if the

core of Jupiter could somehow be made of hydrogen so compact. How compact would it be? It'd be so compact, it would act like a metal. The electrons would move between atoms so easily. And this would inform us a little more about physics, about chemistry, about the cosmos, because most of the cosmos is hydrogen. And so if it behaves in this new, unexpected, or heretofore unexpected way, it would, as I so often say, Matt, change the physics. Which amounts to the world, doesn't it? Yeah, yeah. So it's a cool mission, and it's another thing, everybody, very reasonably priced. You know, I did those videos for it a few years ago.

It's very cool. Scott Bolton and I talk about those during the conversation and how much we both enjoy them. You like the red spot, I heard. That was my favorite, number four. So it's classic. It's just me with the physical models with the props being a hilarious science guy.

I got asked, did you build that model of the red spot with the bands above and below it? Probably. It looked like one of yours. It looked like your handiwork. And hot melt glued the balsa wood. Yeah, all that stuff. There you go.

There you go. It's all—well, this stuff is not at planetary.org. It's on the Juno website. It's the Why With Nye series. There's a bunch of other good resources there. But, of course, we hope you'll take a look at the planetary.org site and our ongoing coverage. Emily Lochte-Wallace, she'll be there for orbital insertion at JPL. I'll be there too, Matt. Well, at least they invited me. I presume I'll show up. They won't kick me out. But you guys, it's an exciting thing. This really is rocket science.

You know, we were talking about this at this Politicon last weekend about the politics of Mars, which is closely related, but there's no business case for exploring the core of Jupiter. You don't really sell tickets to that. It is a society that thinks it's a worthy thing to use our intellect and treasure to explore this other world, to learn more about the cosmos and our place within it. It's a fantastic mission. It's ennobling. Thank you, Matt. Thank you very much.

And I look forward to talking to you next time. And I hope I'll see you there on the 4th of July. On the 4th of July. Independence Day, we're going in orbit around Jupiter. Carry on! Bill Nye, the science guy, is CEO of the Planetary Society. around Jupiter. Carry on! Bill Nye the Science Guy is CEO of the Planetary Society. Another guy who works for him there is the Society's Director of Space Policy, Casey Dreyer. On Saturday, June 25th in Pasadena, Casey led a terrific panel discussion called How We'll Get to Mars. As you might guess,

that how was more about representatives than rockets. Joining him in front of a standing-room-only crowd at Politicon were Bill Nye, former congressional policymaker Bill Adkins of Adkins Strategies, and former NASA Deputy Administrator Lori Garver, who will be my guest on this show next week. We talked moments after the session ended. Casey, great panel. Tell us, what did you want to achieve? There were a couple things I just wanted people to walk out of the room with. You know, these are folks who love politics and they love space, but they probably didn't know that space itself has politics, right? That there's this whole world of people who make decisions about NASA. And so I wanted them to walk

out of here just with an understanding that NASA doesn't get to make decisions in a vacuum, so to speak, right? NASA has to be told what to do by the White House. It can be told what to do by Congress. Different parts of Congress can tell it to do different things. You have a variety of political masters that NASA has to navigate this world within. And we also have this whole new relationship that NASA has with the commercial sector that can impact how the decisions, you know, impact the decisions that it's making, impact the opportunities before it, and also set a number of challenges for it to keep up with this nascent industry that it itself is supporting. And so I just want people to walk out just appreciating that NASA is a complex beast, that they have the role and, in a sense, the responsibility to engage in politically like any other factor of government. You've got a lot of people, mostly young people, waiting here to talk to you and ask you,

I think, how they can be part of this. You just talked to a woman who did exactly that. That's true. Yeah, people are really interested. I think you have this untapped resource of youthful energy who wants to come in and make a difference in politics but love space, right? They've seen what NASA has done. They see what SpaceX has done. And they ask themselves, you know, I'm not an engineer. I'm not an astronaut because few people will have that kind of peak physical capability. But I love politics. What can I do? And that's what I was like five years ago when I came to the Planetary Society. So it's really exciting to see people's interest in this. Just time left now for a shameless plug for what's happening on Friday, July 1st.

Well, Matt, we have this great new podcast called Planter Radio Extra, the Space Policy Edition. We just had our first episode last month. Great, fantastic, wonderful reviews. I was so excited to hear the feedback we got from our members and listeners. I was relieved. I, you know, okay, I thought we did a pretty good show. But I'm really excited we have a new show coming up. We're going to be doing these every month.

We're going to be delving into the weeds of space policy and politics in a way that's totally fun and accessible. It's a great new show, and no one else is doing it. It's going to be very timely. We're going to talk about the Juno mission and Moon versus Mars, which came up in your session today. Absolutely. That's a perennial debate within the human spaceflight community, right?

And we are going to be talking about why people argue this. Just step back from the argument itself and just like, why is this even an issue? And then of course we have Juno going into orbit around Jupiter. Why now? Why Jupiter? Why Juno? Why now? Well, there's a whole process. How does NASA select its science missions? And we'll walk you through that and help you understand what's it take for NASA to explore a new place. It's going to be really fun. Thank you, Casey. I'll be there. I hope so, Matt. You're hosting. Casey Dreyer, he's the Director of Space policy for the Planetary Society. And you can find Space Policy Edition number one and number two at planetary.org, of course. And in a moment, more Juno.

Scott Bolton, the head of that mission, the principal investigator, joins us right here. As I speak, only one spacecraft has ever traveled across the solar system to orbit and study Jupiter. That was Galileo, a mission that ended almost 13 years ago. It's quite possible that by the time some of you hear this, a second emissary from Earth will have been captured by Jupiter's mighty gravitational field. Scott Bolton is principal investigator for the Juno mission, which departed our planet in August of 2011. With just a handful of days left before orbital insertion and with worldwide excitement building, Scott welcomed me to the Jet Propulsion Lab near Pasadena for a conversation about Juno and how the science it seeks may unlock secrets about the origin of our and other solar systems,

and much, much more. Scott spent 24 years at JPL working on a variety of missions and projects. Now this space physicist directs the SWRI, or Southwest Research Institute's Space Science and Engineering Division. Not surprisingly, his research focuses on the formation and origin of, yes, the giant planets in our and other solar systems. Scott, first of all, thanks for getting me into the lab, which was a little bit more of a hassle than usual today. And now we're here at the JPL cafeteria. Yeah, sorry about the little hassle there. Sometimes at the JPL cafeteria. Yeah sorry about the

little hassle there sometimes getting into JPL can be tricky it it is a NASA facility and it's secure so sometimes you need a little more advanced warning and I didn't realize you hadn't been cleared yet. You spent a lot of years here is it good to be back especially with what's coming up? Yeah it's great to be back I mean you know I was here for a really long time and I just have a lot of friends here. And so it's so great to be part of Juno and be part of the JPL team that's making that happen and to come back and see my friends and they all, you know, are helping to celebrate that we're finally arriving. It's great. You've been on the show in the past. We've talked about this years before this great occasion. I have to ask the typical media question. How does it feel

to be really now hours away from this huge event? Yeah, you know, you're the only one that's ever asked that. How do I feel is a great question because I feel really excited that we're finally arriving. And I've got to combat that with the anxiety and tension of knowing how important the orbit insertion event really is. And so I have this mixed set of emotions, this excitement and anticipation that we're finally getting there and we're going to start this cool investigation. and anticipation that we're finally getting there and we're going to start this cool investigation and knowing that, oh my gosh, we've got to get this orbit burned, go just right, or we fly right past the planet and I have no mission. I haven't felt that kind of mixture of excitement and anxiety since the launch where I was really excited we were finally launching, but I was also worried, oh my God, what happens if the launch vehicle blows up?

So that was the largest risk of the mission. And I think this orbit insertion is the second biggest risk. Still, though, it's going to be nerve-wracking, I'm sure. I mean, I was talking to my colleague, Emily Lakdawalla, last week on the show about what's coming. And I mentioned, you know, the seven minutes of terror as Curiosity came down to Mars. You're giving people five times that during this rocket burn. That's right. It's 35 minutes of wringing your hands and squeezing the chair really hard. And at 35 minutes, it gets tough.

Your hand gets tired. Because there's not much else you can do, right? There's not much we can do. I mean, it's all in the hands of the great engineers that program the spacecraft. But it's a smart robot, but it only does what you tell it. Travel of the light time back and forth between Jupiter and Earth is 40 minutes. Our burn is 35. So by the time we know there's a problem, it's too late to do anything. Emily told us, though, that even if the burn cuts off after 20, you won't be in the right orbit, but you'll be orbiting. That's right.

So that's a little-known secret, is that while I'm sitting there, everybody is waiting for the 35 minutes and the rocket to go turn off, and then you're in orbit. But when the clock hits 20 minutes, that's when my relief happens, my first relief, because I know now we're in orbit. It may not be the best orbit, but we can do great science from that orbit. But there's another piece that will keep you tense when you're waiting for this. One is the 20 minutes, and then we're in orbit.

It's better if you go 35 because you're in a better orbit. But regardless, after the rocket is done burning, we must turn the spacecraft back to sun point before the batteries drain out. We have to get power positive. To do the burn, we've moved the solar arrays away from the sun in order to fire the rocket in the right direction. That's the second piece of the tension, is I'm not totally relaxed until the engine's turned off, we're in orbit, and we're backed. And, of course, this is a challenge that no other spacecraft that has been out this far has faced because they didn't have those big solar wings.

That's correct. Every other spacecraft that's gone into orbit, it's Jupiter or Saturn, mainly Galileo and Cassini. They were nuclear-powered. So they had to do all the burn just right, but they didn't have to worry about turning back in time to save the mission. And we will have to do that. I am convinced you have a glorious mission ahead of you. But if you had been able to get your hands on some plutonium and have RTGs instead of those big, beautiful wings, would you have done it? Absolutely. We designed, I mean, the Juno team designed the spacecraft to use solar

power because there was no RTGs available. We set out, I mean, NASA was designing some, but I was a little worried that they were going to get the design and the development and creation of them in time. And so we looked at, was there another option? Could we go solar? Which was an out-of-the-box idea because nobody had ever gone to Jupiter on solar power so we had to do a bunch of testing initially of solar cells low light low temperature they call it lilt and we had to prove that the solar rays or the solar cells themselves what you know their efficiency in this very low light, low temperature situation, and how would they degrade from the radiation.

So if we could have gone RTGs, I would have gone that way. I don't think it would have changed our overall science. We were actually able to implement the science that we wanted with solar, but it would have made life a little bit easier because it wouldn't have mattered where we were pointed. The solar system offers some pretty nasty environments, Venus, Io. The space that you're going to be flying through has got to be high on that list. Yeah, it's at the top of the list. There's no question, very close to Jupiter, is the single

worst planetary environment in the entire solar system. It's because Jupiter is extreme, right? I mean, Jupiter is a planet on steroids. Everything about it is extreme and the most extreme. So it has the single worst radiation belts of any planet. It has the strongest magnetic field, the strongest gravity field. It's spinning the fastest. I mean, they don't call it the king of the planets for nothing field. It's spinning the fastest. I mean, they don't call it the king of the planets for nothing. And it's a beautiful world. What do you hope we're

going to learn about it from Juno? So Juno's science, you know, really addresses quite a few different kinds of objectives. The primary and maybe most important objective has to do with the origin of Jupiter. How was it built? How was it made? What formed it? How did, how, what happened in the early solar system that allowed Jupiter to form a little bit different than the sun? We create a star and then somehow from the leftovers, we make the planets. And Jupiter is the first planet. It's got most of the leftovers. I can take everything else and it goes inside Jupiter, right? All the other planets, asteroids, comets, everything, don't add up to Jupiter.

So it took most of the material. So it's that first step between the transition of making a star and making the solar system. I mean, we're really after the recipe for the solar system. How do you make them? How do you make our solar system? How do you make the other ones that are out there that we're discovering after the recipe for the solar system. How do you make them? How do you make our solar system? How do you make the other ones that are out there that we're discovering around other stars? And Jupiter kind of holds that first key secret for us.

And what we're doing is investigating its interior structure, whether there's a core of heavy elements in the middle of it. What's the water abundance? How much oxygen is inside Jupiter? What are the deep dynamics? What's going on in the deep atmosphere? How deep are the zones and belts go? What's the roots to the Great Red Spot? How is it structured inside? What makes the magnetic field? And finally, how does the polar magnetosphere work? These are

the most powerful auroral emissions in the entire solar system. So we, across the board, are investigating all of those kinds of objectives at the same time. Scott Bolton is principal investigator for the Juno mission, arriving in Jupiter orbit on July 4th. He has much more to tell us after the break, and there's even more from Scott in the online version of this week's show. Planetary Radio returns in a minute. This is Robert Picardo. I've been a member of the Planetary Society since in a minute. across our solar system and beyond. You can join me in this exciting quest. The journey starts at planetary.org. I'll see you there.

Do you know what your favorite presidential candidate thinks about space exploration? Hi, I'm Casey Dreyer, the Planetary Society's Director of Space Policy. You can learn that answer and what all the other candidates think, at planetary.org slash election2016. You know what? We could use your help. If you find anything we've missed, you can let us know. It's all at planetary.org slash election2016. Thank you.

Welcome back to Planetary Radio. I'm Matt Kaplan, still visiting with Juno Mission Principal Investigator Scott Bolton in the cafeteria at the Jet Propulsion Lab. It's at JPL on the 4th of July that Scott will lead an anxious team and world as the spacecraft attempts to enter orbit at Jupiter. Give us the thumbnail description of the instrument suite that is on board that's going to deliver all this data. We're trying to measure the invisible force fields around Jupiter. That's how you get to the interior. So we look at the gravity field.

We measure the magnetic field with magnetometers. The gravity field is investigated using Doppler through the communication system. So we're watching the orbit change as we fly by. We're measuring the internal magnetic field with our magnetometers. We have microwave radiometers. Those are like radio antennas that work in the microwave regime. We have six of them. They basically see through the clouds for us.

They can tell how much water is in Jupiter. They can see how deep the zones and belts go. We also have a full suite of instruments to look at the polar magnetosphere. We have infrared and UV spectrometers and imagers, high-energy particle detectors, low-energy particle detectors, and plasma and radio wave. And then finally, we have a visible camera called JunoCam. Ah, let's talk about that. Because as I told you before we got started, Candy Hanson on your team, who's in charge of JunoCam,

was on the show just two weeks ago talking about that camera, which is pretty special, not so much for its technology, but for why it's part of this mission. That is a really special camera. We designed it to be able to take a picture of Jupiter's poles when we flew over. I couldn't imagine going to Jupiter and not being able to see what the poles look like, especially after seeing the surprise that Saturn had for us. Here we're going to fly over the poles for the first time.

We've got to take a look and see what do they look like. But, of course, the camera's even more powerful than that. We're going to get great images really close up. We're going so close to Jupiter, 5,000 kilometers above the cloud tops. We're going to see what those beautiful zones and belts and clouds really look like up close and personal. So JunoCam represents this great opportunity for us to see these beautiful pictures, but it also represents an opportunity for us to have the public join our team. And that was really important to all of us. And so we set up something on our website, the missionjuno.swery.edu, or you can go to missionjuno.com.

It'll work the same way. And we'll include that URL on the show page as well. Okay. And you can go to that website and not only get the raw images and sort of make your own picture but eventually you will be able to go on and the public will be able to go on and help vote and decide what do we take pictures of we want the public's opinion of what what do they want to take a picture of we have amateurs loading up pictures of jupiter so that the public can look and say oh here's a cloud feature i want to take a picture of. We have amateurs loading up pictures of Jupiter so that the public can look

and say, oh, here's a cloud feature I want to take a picture of. They have to make their case. Why is that one more important than when some other person wants to take a picture of? And we will let them vote and the highest votes, that's where we'll point the camera. And then when the data comes down, they can process that data and post their own pictures. Maybe they'll make different colors. Maybe they'll make different resolutions, different montages. It'll all be great to have the public involved. They'll be part of our team, basically. To an unprecedented degree, it sounds like.

That's what we wanted to do. We wanted to open it up so that the public could join us and enjoy the exploration with us to both inspire and motivate them, but in a way that maybe was even more involved than they've been able to enjoy with other missions. And I think that's the right direction. I'm hoping that whole classrooms get involved. Even for people who don't, you know, deal with images in the way that you're talking about, manipulating them, or even if they don't vote, you've provided a lot of stuff for other folks to do, and I have to bring up here the work by my boss, the science guy.

It's this Why With Nye series, part of the education and public outreach arm of this mission, which you also oversee in addition to everything else that's going on. Yeah, Bill Nye's great, and luckily I happen to know him. And so when we were trying to think of things we could do to help bring in the public, and we want to be able to bring in all ages, right, all different types of people, you want to have something for everybody. Bill, of course, has an incredible following, great sense of humor. And I just called him up one day, and I said, how about doing something with us?

And he goes, what do you have in mind? And I described it, and he goes, okay, that sounds great. And he made a series of videos with us that were fantastic. There's one in particular, I think I've seen all of them, the number four. And it's just hilarious, first of all, because it's pure nigh. And he talks about the great red spot, which of course captures everybody's imaginations and why it stays where it is and so on. I mean, is understanding that kind of phenomenon the kind of thing that also might come out of Juno? Absolutely. I mean, you know, we have these high-level objectives that include the formation of Jupiter and maybe the history of volatiles and water all across the solar system. But we also

have the ability to look underneath the surface, or I should say the top cloud layer, because Jupiter doesn't really have a surface, and see how deep do the red spot roots go. Presumably they must be pretty deep because the storm has lasted so long. Our microwave radiometers will sort of sense the heat and pressure and the emission coming out of Jupiter deep, deep down, 100 bars, even maybe some hints of 1,000 bars down below the top layer. And if there's variability in that that's consistent with the red spot that we see on the top, then we're going to know the red spot goes down that deep. And that's pretty good news.

Back to the poles for a moment. You compared it to what Cassini revealed there, and I assume you're talking about those incredibly strange hexagons. Do you expect surprises like that when we see the top and bottom of Jupiter for the first time? Well, I'm reluctant to say I expect it to be a hexagon, but I certainly expect surprises. I mean, that's part of the reason you go out and explore, is you don't really know. If I knew what we were going to measure completely, it wouldn't be so exciting. So I expect we're going to see things that we don't understand, we didn't expect.

And the poles of Jupiter, I actually have no idea what to expect. And so no matter what I see, it's going to be unexpected. I suppose if it looks exactly like Saturn's and there's a hexagon there, I would be surprised at that even. In less than a week, this will be a madhouse because it will be the center of media attention, at least the center of science media attention, as everybody joins you grabbing onto the arms of the chair, hoping those rockets fire as they're supposed to. How soon after that will the science start to come back? Five days prior to July 4th, we'll turn off all the science instruments

because we need the spacecraft to be focused on the engineering activity we need to do. So we don't want even the spacecraft to be distracted. So the science instruments go off five days, and then right after JOI, they go back on. And so we'll start getting some data. But the first orbit is 53 days long. So we don't come close to Jupiter until the end of August. And that will be the first time that we fly by Jupiter with all of Juno's eyes and ears open. And we'll see for the first time all of these key new discoveries that

Jupiter's holding for us. I think the first science will be, it'll come down right after the end of August. So by the first week of September, we will have our first glimpse. We won't have all the answers yet, but we'll certainly get data that is surprising and fantastic. I'm incredibly fortunate to be able to talk to people like you who are part of this pretty small fraternity or sorority club of principal investigators, project scientists, who get to realize these dreams that you're among them. You've been working on for so many years seeing this all come together. It's a pretty fortunate position. It is. I feel really lucky to be part of this team and to be able to share in the excitement so up close and personal.

And in fact, it's that excitement and that I'm so thankful to be part of the team is part of the reason I want to reach out and let other people share. I think it's really lucky that I'm able to be part of this. I worked hard for it. But I really believe that we're all doing this together. And my position is really to represent the rest of the public that maybe didn't get so lucky to be part of this mission, but they can share in the results. We're all reaching together out, trying to learn about ourselves and nature.

And if we didn't reach together, we really couldn't reach at all. Well said. You ever read the book 2010, the sequel to 2001 by Arthur C. Clarke? Absolutely. And the movie, of course, as well. And Dave Bowman, right out there

where you guys are going to be flying around, delivering science, said something wonderful is going to happen. Well, I think something wonderful is going to happen. Well, I think something wonderful is going to happen. Yeah, I agree. I mean, it's going to be wonderful to get so close to this giant planet and learn so much about not only Jupiter's history, but our whole solar system's history.

We're really going to learn about our interaction with nature, how it all works, what is the first step when you go to make the planets, what's some of our own history. Jupiter is made of almost the same thing as the sun. It's almost all hydrogen and helium. But we've learned from previous missions that it's enriched in what we call heavy elements, the carbon, the nitrogen, the sulfur. We don't actually know why or how that happened, but we know it's important because the stuff that Jupiter

has more of is what we're all made out of. And so it comes back to us. Jupiter represents that first step that must have taken place very early in the solar system where the sun forms and already the planets are getting their endowment of these heavy elements. They're getting enriched. And we don't know how that happens, but we know that it's important because whatever the reason for that happening, it's responsible for our existence. Thank you, Scott. And best of luck on the 4th of July and in the months to follow as Juno reveals this glorious planet.

Thank you. And thank you and all of your audience for sharing this journey with us. Time for What's Up on Planetary Radio. Bruce Betts is the Director of Science and Technology for the Planetary Society. He is on the Skype line. We have a special message from listener John Gallant in New York. He says, the world wants a picture of Bruce's new fashion fad, the mask earring. A little scared to put that out in the world, but maybe it will start a fashion fad. We'll see.

You need to give Zoolander a run for his money. I want to see your version of Magnum. I'll work on the look that goes along with the mask earring. What's up? All right, we got our three friends in the evening sky still. We've got Jupiter over in the west, brightest star-like object over there in the early evening. And as you move towards south and east,

you will see Mars, which a little tidbit about Mars, it is now merely as bright as the brightest star in the sky. Dimmer than Jupiter. It's about serious brightness. It will continue to dim, so check it out because it's still bright, pretty reddish, and then Saturn is not too far away from it, much dimmer and yellowish. We move on to this week in space history. In 1971, we honor the death of the Soyuz 11 crew who died during reentry. And then in 1908, the Tunguska impact is a roughly 30-meter asteroid or comet object

exploded high over Tunguska, Siberia, leveling 2,000 square kilometers of forest. So we use that as a reminder that asteroid defense, it's important. Happy Asteroid Day to all. Happy Asteroid Day. I don't know what the right presentation of that is, but yes, acknowledging Asteroid Day and the importance of planetary defense. We move on to... And I got a good one for you next week. We move on to Romans Bay.

And I got a good one for you next week. Just wait. Oh, I can hardly wait. The center density of the sun is more than 12 times the center density of Earth. But the average density of the sun is only about 25% the average density of Earth because it gets all light and fluffy towards the outside. Chewy on the inside, but no. If the Earth were big enough, would the sun float

to say nothing of what it would do to the water? Yeah, yeah, I suppose so. Well, wait. No, it would not float in water. It has an average density of about 1.4 grams per cubic centimeter water by definition has a density of one gram per cubic centimeter thank you that's a good float in molten earth so if you whip up a shake of molten earth and it's big enough to put the, this is just ridiculous. But okay. All right, we move on to the trivia contest.

And I ask you, what was the first human spaceflight of the Chinese space program? How'd we do? A very big response this time around. Bigger than usual. Chosen by Random.org was, full disclosure here, Craig Jernay in Los Alamitos, California. Been about two years since Craig has won the contest, but he hung in there. It really was just chosen by random.org in spite of the fact that I used to work with this guy. And that's why I happen to know that he used to work on the Deep Space Network out at Goldstone.

So interesting guy. His answer was that that first human spaceflight by the Chinese, Shenzhou 5. That is correct. Then, Craig, you have won yourself a new Planetary Radio t-shirt. We might have had the old style the last time he won. A genuine Planetary Society rubber asteroid and a 200-point itelescope.net astronomy account for the worldwide network of telescopes operated by those good folks at iTelescope. So have fun with that. John Kurtz in Naperville, Illinois, said that loves space science

and spent a lot of time in China, so he's a good person to explain this to us. Shenzhou roughly means boat of the gods or vessel of the gods. Shenzhou means god god and Zhu meaning boat. He was also one of many people who said that space capsule was piloted by Yang Liwei, who was not even born when the first humans, the first Soviet and the first American went into orbit. In fact, he was only 19 years old when the first ethnic Chinese person went into space. That was Taylor Gunjin Wang, who was a JPL employee and a payload specialist on STS-51B.

We got that from Martin Hajoski. Wow, good stuff. And Dave Fairchild chimed in. Russia and NASA had been the first two to orbit a human in space, and then the Chinese said, hello, if you please, we'll add Shenzhou 5 to the race. Thank you, Dave. We move on. Matt, I know you like to hang out on the surface of the sun.

I go at night. Brilliant, brilliant. If Matt or anyone is on the surface of the sun, moments before they vaporize, and by surface of the sun, we're going to define that as it's usually defined as the edge of the photosphere, so the visible surface. What do we see at visible wavelengths? What is the ratio of the equatorial surface gravity of the sun at its surface compared to that of Earth approximately?

In other words, how much more pull downwards are you going to get? So how much are you going to be pulled downwards while you're being vaporized? Did that make sense, Matt? Absolutely. I love that. That's a great question. All right. You can give it in terms of Earth. So it's ratio. So give it in terms of Earth's surface gravity, 1g often is the terminology. Go to planetary.org slash radio contest. You got until July 5th, Tuesday, July 5th at 8 a.m. Pacific time, and you'll get that same prize package, a Planetary Radio t-shirt, a rubber asteroid, and a 200-point itelescope.net account. We are done.

All right, everybody, go out there, look up at the night sky, think about bumper stickers and where have they gone? Thank you, and good night. I wonder if Shenzhou 5 had a bumper sticker. He's Bruce Betts, the Director of Science and Technology for the Planetary Society, who joins us every week here for What's Up. Asteroid Day is or was June 30th. I promised you last week that we'd be marking it with yet another special segment. That segment is waiting for you at planetary.org slash radio, as well as iTunes, SoundCloud, and many other online sources.

It's a fascinating conversation with UCLA grad student Adam Greenberg. Adam talked with me from the giant radio telescope at Arecibo, Puerto Rico, where he was using that Great Dish's million-watt radar beam to explore a near-Earth asteroid. Planetary Radio is produced by the Planetary Society in Pasadena, California, and is made possible by its Jovial members. Josh Doyle composed our theme, which was arranged and performed by Peter Schlosser. I'm Matt Kaplan. Clear skies.