Planetary Radio: Space Exploration, Astronomy and Science - Alan Stern's Biggest Planetary Science Mysteries

Episode Date: June 8, 2009

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Hey there, faithful podcast listeners. It's Matt, coming to you unscripted, unplugged, mostly, with another one of our little secret podcast listener messages, just for you guys. We haven't done this in a while, but we have a very good reason to make a special appeal to you now. And when I say appeal, that's exactly what I mean. I don't have to tell you that times are tough all over, and they're especially tough for non-profits, and that's what the Planetary Society is. But the Society does need to look for ways to save money, and one of the things being looked at very seriously is this podcast. So we've decided that it was time to ask for your help. So we've decided that it was time to ask for your help.

If it's not there yet, in a day or so, you'll be able to find at planetary.org slash radio a special new link that will allow you to make a donation directly to Planetary Radio without having to become a member of the Planetary Society. Now, of course, we'd love for you to become a member of the Planetary Society, Thank you. over $50 U.S., we'll get you a Planetary Radio t-shirt. You won't even have to answer a trivia question. Anyway, we hope you can help us out. We'd like nothing better than to keep bringing you the most exciting news and people who make the news in space science, planetary science, and really news from all over the universe. We love you folks, and we hope we'll be able to keep doing this for a long, long time.

Once again, that donation link should be at planetary.org slash radio. Thanks very much. Here's the show. Alan Stern's Biggest Planetary Science Questions, this week on Planetary Radio. Hi everyone, welcome to Public Radio's travel show that takes you to the final frontier. I'm Matt Kaplan of the Planetary Society. We've learned so much about our universe, but so many unanswered questions remain. And it's these questions that drive science forward. Planetary scientist Alan Stern will share some of his favorite mysteries on today's show.

We'll also catch Bruce Betts in Manassas, Virginia, where he was helping to prepare the life experiment for a round trip to Mars' moon Phobos. As always, Bruce knows where to look in the night sky for our planetary neighbors, and he knows the answer to our space trivia contest. Or does he? And just because we miss her, stay tuned for Emily Lakdawalla. Emily will be on maternity leave for another month or so, but I found a classic edition of her Q&A segment that is more relevant than ever as Saturn fast approaches its equinox.

NASA has targeted June 13 for the next space shuttle launch. It's Endeavour's turn to visit the International Space Station for completion of the Japanese lab called Kaibo. It will take five spacewalks and 16 days. We also want to mark the recent launch of Herschel and Planck. These European Space Agency spacecraft went up on the same Ariane 5 booster last month, but with very different missions. Herschel will use the biggest mirror ever put in space to help us learn about the formation of stars and planets,

while Planck will look back to just 400,000 years after the Big Bang. There's more news at planetary.org, but let's turn now to Bill Nye. We caught Bill on the road returning from a meeting of the Federation. No, not that Federation, but close. The Federation of Galaxy Explorers was created to inspire and educate kids about space science and engineering. Bill helped host their Galactic Ball on June 6th. Our only chance to hear from the science and planetary guy came as he ran from one plane to

another at the Denver, Colorado airport. So when he says he's got to fly, you know he means it. I'll be right back with Alan Stern. Hey, Bill Nye, the planetary Guy here. I was in Washington, D.C. this weekend for the Federation of Galaxy Explorers banquet. And Miles O'Brien, the CNN reporter, was given an award for his contribution to the communication of space. But the exciting thing was all the young people, all the young people who were getting involved in rockets and space exploration. all the young people who are getting involved in rockets and space exploration. Now, I admit, there are a lot of military people who are kind of a throwback, really want the United States to go back to the moon because other countries are going to go there. But as you may know, my feeling is no hurry to go back to the moon to the United States. We've been there 40 years ago.

But nevertheless, young people are excited. They're exploring space, not at the same level as the Cold War. Not as many people are involved, but the people who are involved are as passionate as ever. And here's hoping that with your support as members of the Planetary Society, we can continue to explore the nearby planets, continue to explore the Lagrange points. There was a lot of talk about that. These are points where the gravity is balanced, so you can put a spacecraft out there without using as much rocket fuel as you might use to go to other places. We can continue to explore the nearby solar system

as well as distant stars with telescopes in space. We can. Dare I say it changed the world, and seeing the Federation of Galaxy Explorers, as they're whimsically called, was really heartening. Well, thanks for listening. I've got to fly. Bill Nye, the Planetary Guy.

Even though he's no longer an associate administrator at NASA, Alan Stern remains one of the busiest planetary scientists around. Time magazine named him as one of our planet's 100 most influential people not long ago. He may be best known at the moment as the principal investigator for the New Horizons mission to Pluto and beyond. New Horizons will reach Pluto and Charon in July of 2015. We've talked with him several times about that journey, and we'll get another update in a moment,

but what really made me want to talk to Alan again was a recent entry he penned for the Planetary Society blog. He called it, Ten Things I Wish We Really Knew in Planetary Science. It was just one of his contributions, as the Society offers special guest bloggers a chance to fill in for Emily Laktawalla during her maternity leave. We've got a link at planetary.org slash radio. Alan is also an associate vice president at the Southwest Research Institute, and that's where we caught him a few days ago.

Alan, it's been too long. Welcome back to Planetary Radio. Thanks, Matt. It's good to be back. You know, we're going to talk about these questions that you've posed, not only for others, but for yourself. The 10 things you wish you and we really knew in planetary science. We're not going to be able to get to all 10, or actually 11 of them. I know you've picked out five. We're going to start that in a second, but I'm sure that folks would also like to hear what's the status of that little spacecraft that's headed out to the outer reaches of the solar system. Well, New Horizons, a little spacecraft that could, is barreling its way in the depths of space between Saturn and Uranus, just past 13.5 astronomical units from the sun,

in very good health as it hibernates. We'll be waking it up next month at the start of July for a couple of months of checkouts and updates, and then we'll put it back to bed as we keep flying it farther and farther. Six years to go. Six years to go. Very exciting. I couldn't help wanting to mention this little fascinating segment that I found on your website, and we'll put a link up to the site, of course, about Venetia Burney Thayer,

who passed away at the age of 90 just last month, actually in April, April 30th, in England. What was the significance? Why did she end up on the site? Well, Venetia essentially named Pluto in 1930. When she was 11 years old, she suggested the name Pluto as a student. And, of course, that was the name that was ultimately adopted for the ninth planet. You know, she has a little bit of astronomical history to her credit. You got to meet her, I'm told. That's right. You know, after we launched, because we're flying the first student-built instrument on a planetary mission,

we decided to honor her by renaming the instrument from simply technical name, the Student Dust Counter, to the Venetia Burney Student Dust Counter. On a trip I was making, for other reasons, I joined up with Mihai Harani of the University of Colorado, who's our instrument PI for the student dust counter. And we spent a day with Venetia and her son, made a formal dedication, had a little ceremony and so forth. And she was just an absolutely bright and delightful lady, even at 87 years old.

And it was just a pleasure getting to know her. What did she have to say about your mission? She was amazed that after all these years that we were picking up where Voyager had left off with unfinished business and going on to reconnoiter the Kuiper Belt, and in particular its most famous member, Pluto. Well, it's a wonderful little feature, and thank you for marking her passing. Hey, we better get on to these five questions that you've selected out of the larger group, because it's still going to be a whirlwind tour. And let's start with this one, which I'd say deserves the number one spot.

How many worlds harbor life in our own solar system? Isn't that something that everybody wants to know? Conventional wisdom used to be that most of the worlds after the initial reconnaissance look not very likely as potential abodes for life. But I think that the ball has moved quite a ways downfield on that. And now we're beginning to see evidence of energy sources, liquid water, even carbon-bearing compounds, organic chemistry in a whole variety of places across the solar system, from the potential for oceans inside Europa to the organics on Titan, oceans inside

many of the satellites, of course Mars. I think the most interesting thing about this question, and we may not know the answer for a long time, but the most interesting thing is that if I had to place a bet, my bet would be that we're likely to find more worlds harboring life in the outer solar system than in the terrestrial planet region when it's all said and done. But I might be wrong. We'll just have to go and see. Yeah, let's go and see as soon as we can, okay? Here's number two. How common are solar

systems with architectures like ours, i.e. rocky planets on the inside, giant planets in the middle zone, and dwarf planets, so-called, and comet reservoirs, lots and lots of them, on the outside? Yeah, you know, that's the description of our solar system, and we have yet to find an analog to it. All the ones that are being discovered around other stars are very different. We find pulsar planets, or we find Jupiters in very tight orbits inside even where Mercury would lie, for example. Now, that doesn't mean that our solar system is a rare architecture,

but the techniques that we now have to look for planets bias the kinds of things we can find. When we have better techniques, we'll be able to find a greater variety. And I just wonder if ours is typical, or if ours is really the odd bird. It's a question that keeps me awake some nights. I guess this has, though, shaken the faith of some folks who thought that we were, you know, the model for the galaxy, if not the universe. So far, not so much. You're right. It's another part. It may be another part of the Copernican Revolution.

Just as the Earth was displaced as the center of the universe, and the sun is nowhere near the center of our galaxy, it may turn out even that our solar system is quite the minority type. We'll see. And I'm delighted every time that happens. Stay with us for more big planetary science questions from Alan Stern. This is Planetary Radio. Hey, hey, Bill Nye the Science Guy here.

I hope you're enjoying Planetary Radio. We put a lot of work into this show and all our other great Planetary Society projects. I've been a member since the disco era. Now I'm the Society's Vice President. And you may well ask, why do we go to all this trouble? Simple. We believe in the PB&J, the passion, beauty, and joy of space exploration. You probably do, too, or you wouldn't be listening. Of course, you can do more than just listen. You can become part of the action, helping us fly solar sails, discover new

planets, and search for extraterrestrial intelligence and life elsewhere in the universe. Here's how to find out more. You can learn more about the Planetary Society at our website, planetary.org slash radio, or by calling 1-800-9-WORLDS. Planetary Radio listeners who aren't yet members can join and receive a Planetary Radio t-shirt. Members receive the internationally acclaimed Planetary Report magazine. That's planetary.org slash radio. The Planetary Society, exploring new worlds. Welcome back to Planetary Radio. I'm Matt Kaplan. Alan Stern is in the middle of sharing with us some of his greatest planetary science mysteries.

Alan is an Associate Vice President at the Southwest Research Institute, Principal Investigator for the New Horizons mission to Pluto and the Kuiper Belt, and is deeply involved with more missions, universities, and aerospace firms than we have time to mention. He also helped run NASA as an associate administrator in 2007 and 2008. So far, we've heard two of his big questions. Let's go on to number three. What causes Triton's surface to be so young, so long after that dwarf planet's internal engine should have run down?

You know, one of the biggest mysteries, from my perspective in planetary science, is the activity of Triton, which is a small world, 2,700 kilometers, and yet its surface is so young that it's essentially indistinguishable from zero in terms of surface age. And when Voyager 2 went there, it saw ongoing activity in the form of geysers and resurfaced terrains where there are no craters. And we don't understand why a world that small should be able to run for 4 or 5 billion years. Now, an interesting possibility has come up recently, suggested by Doug Hamilton and Craig Agenor. It may be that we know Triton was captured from solar orbit. It was

formerly a planet in and of itself. What Agenor and Hamilton suggested is that the capture mechanism was that Triton was a binary planet, like Pluto, and that the other member was slung out of the system, and Triton was the one that lost energy and was captured into orbit. If that happened recently, then the subsequent thermal evolution may still be going on as Triton breaks through tidal interactions. And we may be seeing activity simply because of a recent capture. But it might be that we don't understand the physics of small planets. But it might be that we don't understand the physics of small planets. And I think either is exciting, and either has a lot to teach us about the history of our solar system and how things work.

Fascinating. Here's another one, number four. How many planets are hiding in the deep outer solar system beyond your fave, Pluto. Well, there are strong lines of circumstantial evidence now that the Kuiper Belt and Oort Cloud may contain hundreds, perhaps even a thousand dwarf planets like Pluto and potentially a collection of other worlds that were formed in the middle zone of the solar system but ejected by the giant planets. Mars-sized, Earth-sized, potentially even giant planet core-sized worlds, may be lurking in the Oort cloud,

which I like to call the solar system's attic. And someday we'll have that census. And I suspect that we'll end up finding that almost all the planets in our solar system are way out there in the frozen deep, and only a select few were lucky enough to be in the warmth of the sun. How much hope do you have that your spacecraft, New Horizons, might show us a few of these? Well, we're not built to look for new places. We don't really have the radio communication system or the onboard telescopes to do that. We're really built for visiting places up close and reconnoitering them.

Of course, we'll visit the whole Pluto system and all of its moons, and then go on to one or two Kuiper Belt objects beyond. Okay, here is number five, and I think it's one that you have a lot of personal experience with. If I remember correctly, you've looked for these guys. Are there vulcanoid asteroids orbiting close to the Sun inside Mercury's orbit, or not? You know, I really want to know the answer to this. Every dynamically stable niche in the solar system is occupied by objects. Every place we can

show the orbits are stable, we find either the debris of planet formation or planets themselves. And when you look at Mercury, you see all those craters, you know that many of those projectiles used to be orbiting close to the Sun. The question is, are there any orbiting close to the Sun today other than Mercury? And if so, the prize is pretty great, because it might be a sample of the material out of which the innermost planets were made, an original sample that's not been processed by planetary geology and so forth. It's very hard to look for these vulcanoids, but a number of teams are trying,

and I expect that before the next decade is out, we'll have a final answer. Alan, you've done so well. Can I throw you, give you 30 seconds to answer another one that deserves at least 10 times that? Sure, we'll try. Here you go. How many times did life originate on Earth? It sounds like not just punctuated evolution, but punctuated creation. Well, Matt, you know, if life was easy to make on the Earth, and the Earth was undergoing

heavy bombardment, as we know it did in the early days, then life was easy to make on the Earth and the Earth was undergoing heavy bombardment, as we know it did in the early days, then life may have been wiped out and had to restart several times. Or it may have been that life was tough to start and only occurred this once. We don't know, but it sure is an important question, I think, about the history of life on Earth and our understanding of life in the universe. So I'd like to have the answer to that. Can you imagine ever losing your excitement over questions like this? No, planetary science is just the best, isn't it?

Big questions and high technology. Who could ask for a better combination to go off sleuthing the universe? And who could ask for a better opportunity than we have with shows like this to be able to talk to folks like you who are asking and sometimes getting answers for those questions. Alan, thank you so much. I really appreciate the chance to talk again. Thanks, Matt. Alan Stern is an Associate Vice President at the Southwest Research Institute,

consultant all over the place, and as you've heard, the principal investigator for the New Horizons mission, which is now headed to Pluto, about six years to go before its closest path to that planet out there on the edge of the solar system, or maybe not quite the edge of the solar system. He is, of course, a planetary scientist. He's also the former associate administrator, one of the associate administrators at NASA. And Alan, we're going to put up links both to your blog entry where people can see the rest of the questions that you have about our solar system, and also to your information at

the SWRI site where they can see the smiling photo of you in an Aloha shirt. And let me just say, I like you a lot better in this than I did in the suit. Thanks, Fred. I do, too. Alan Stern has been our guest. And Bruce Betts will be our guest, as he is every week, when Planetary Radio continues with What's Up in just a moment. Hi, I'm Emily Lakdawalla with questions and answers.

A listener asked, Which would give Cassini a better view of Saturn's equinox, an orbit in the plane of the rings or one out of the ring plane? When the science team wants Cassini to focus on the icy moons in orbit around Saturn, it's best to have Cassini orbit in the same plane as the moons and rings because that increases the chance of moon flybys. But for most of the other scientific disciplines, it's best to have Cassini flying above and below the ring plane in an inclined orbit.

Cassini arrived at Saturn during late summer in the southern hemisphere, so since the mission started the Sun has illuminated the south poles of Saturn and its moons, and the southern face of Saturn's rings. The equinox arrives in August 2009. The coming of spring to a planetary hemisphere always brings big changes, but the changes should be even more dramatic on Saturn's rings, because the entire ring plane sees only one sunrise and one sunset every year. The greatest drama should happen in the most opaque ring.

The blocks of rock and ice that make up the densest B ring are so tightly packed that they don't travel from the day side of the rings to the night side of the rings as they orbit Saturn. That means that the day side of the rings is nearly 100 degrees Celsius warmer than the night side. When the sun rises on the north side of the rings, we'll see all of that change, and it could have surprising effects. When the equinox comes, Cassini will be near its closest approach to Saturn, and on the south side of the rings, watching the sun set. Just hours after the equinox, Cassini will pass to the north side, and be able to watch

the sun rise over the north side of Saturn's rings for the first time in 15 years. Got a question about the universe? Send it to us at planetaryradio at planetary.org. And now here's Matt with more Planetary Radio. We do have Bruce Betts on the Skype connection, and he is reporting in. Well, where are you and why? I am in Manassas, Virginia.

Just because you're a Civil War buff or what? No, but I'm getting there. Yes, they enjoyed it so much in the Civil War, they didn't just have one battle here, they had two. That's right. But that is not why I am here. I am here because this is where ATCC is located, the American Type Culture Collection, who we are partnering with on our Phobos Life Project. I've been working with them in the final loading of organisms for our Phobos Life Project that we will be delivering soon for launch on board the Phobos Grunt spacecraft, which will be launching to Phobos and then coming

back, returning our samples three years later, and scheduled to launch this October. Pretty exciting mission all by itself, sample return from Phobos, but even more so with this little canister of critters that you've been carrying around but even more so with this little canister of critters that you've been carrying around. It's true, the little canister of critters. It'll be the first time we're testing whether life can survive out an interplanetary space for multi-year periods, returning it back to Earth. We're excited, and it's been great. The ATCC group are so very competent and professional, and it's been a wonderful experience. They have like a drive-through window for critters, or what?

They do, but you can also mail order them. They are the place in the U.S. to store your bugs, your organisms, your microorganisms. If you've done studies on them and you send strains to them, they store them. Someone else wants to play with them either in their lab or their high school science class. They're the place to go. But they also have some, not surprisingly, very competent biologists on staff that are experts at storing microorganisms, which is exactly what we wanted. Are they excited about this thing? They are. They're probably tired of having us around for a few days.

But other than that, I think they're excited that, A, we're leaving, and, B, that the experiment is cool and something different, and that their organisms get to go to space. Tell us about what's up in space right now. Tell us about the night sky. All right. We've got in the pre-dawn sky over there in the east, spectacular Venus. Snuggling up pretty darn close to it these days, reddish, much dimmer Mars. Then to its far upper right over in the southeast in the pre-dawn, you'll see also extremely bright Jupiter in the evening sky. Over in the west in the evening, we've got Saturn up

in Leo looking kind of yellowish and like a bright star. And I think you've got my year in space calendar because I left it at the Planetary Society. I don't imagine you have your copy along. because I left it at the Planetary Society. I don't imagine you have your copy along. No, I stole your copy, and it almost made the final cut to come with me to Virginia. No. Darn those weight limitations.

No, this week in space, there was work done on packing up organisms for the Phobos Life Module in 2009. All right, so back next week with that little piece of, that little feature within WhatsApp. Do we then go on to? We do. We go on to random space fact. But you know what?

I'm using my elective once every six or seven years. Yes. I transform this into random bio fact critters and bugs in space biologists and and they've been telling me all sorts of creepy things there are at least 10 times as many bacteria cells as human cells in the body are you joking Ten times as many bacteria right now inside me? Yeah, yeah, in or on you. Most of them in your gut, but, you know, all over you. It's a party. They're mostly much smaller, apparently, than the human cells, so they don't outweigh us, but they do outnumber us. I am going to fire my immune system.

As people will point out, some of them are actually beneficial. Most of them are just hangers-on that like a nice warm place to hang out. All right. Well, they're tough little critters, I guess, and we'll see if some of those can make it to Mars and back, or at least Phobos. Mostly sitting critters that don't hang out inside us. Seeds. We've got water bears. We got animals. But mostly we have representatives of all three domains of life, the bacteria, archaea, and eukaryota. Yes, and the eukaryota, that's our family.

That's us. That's us. That's our domain. Anywho, anyway, let us go on to the trivia contest. I shook things up by asking you who is the second oldest person to fly in space, John Glenn having been the oldest person to fly in space. How did we do, Matt? Well, first of all, I beg to differ about John Glenn. Well, I guess you did put that small qualifier on it of person. You might have even been human. But we did get from Ivan Winther, Yoda, who was 877 years old.

Slightly beating out John Glenn, actually. Just slightly. Yeah. But your question was, who was second, right? Yes, who was second to John Glenn, not counting Yoda. And we got a surprise because neither of us figured this out, but several listeners, and there was a lot of disagreement about this, but several listeners figured it out.

It was not anybody on a space shuttle or on a Soyuz or any other way to get the International Space Station. It was Mike Melville, the pilot of Spaceship One. He was 64 years old or 63 or 62, depending on who you talk to, followed by Story Musgrave, who was either 61 or 60. Or 62. Or 62. What does this tell us?

That astronauts lie about their age. Well, really, that's the conclusion I was going for with this question. Well, for this answer, we're going to get a T-shirt out to Eric Bruner, who I thought had won before, but I think he is a first-time winner in Cary, North Carolina. Send him out the T-shirt and an Oceanside Photo and Telescope Rewards card. Congratulations, Eric. Nice job. I think we'll give something a little easier and less insightful this time around, but equally as fascinating,

what are the two brightest stars in the constellation Orion? Two brightest stars, constellation Orion. Go to planetary.org slash radio. Find out how to enter. And, just in case you're wondering, you have until June 15, Monday, June 15, at 2 p.m. to get us that answer.

Have a good trip home. Thank you. All right, everybody, go out there, look up the night sky, and think about that artwork in hotel rooms. Thank you, and good night. You want to be a little bit more descriptive of that masterpiece hanging over your bed?

Something involving a burn? I think. All right. Column? Are those skulls? No, no. Gosh, maybe not. He's Bruce Betts, the director of projects for the Planetary Society.

He joins us every week here or there for What's Up. Planetary Radio is produced by the Planetary Society in Pasadena, California. Have a great week.