Planetary Radio: Space Exploration, Astronomy and Science - Japanese Hayabusa Probe Reaches Asteroid

Episode Date: September 19, 2005

Project Manger Junichiro Kawaguchi celebrates the arrival at asteroid Itokawa, with further insights provided by former JPL Director Bruce Murray. Q&A on ice volcanoes, and a new trivia contest on What's Up.Learn more about your ad choices. Visit megaphone.fm/adchoicesSee omnystudio.com/listener for privacy information.See omnystudio.com/listener for privacy information.

Japan Reaches an Asteroid 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. Little Hayabusa has reached an asteroid named after the father of the Japanese space program. Right now, the probe is hovering only about 20 kilometers, or

12 miles, above Itokawa, carefully examining the kidney bean-shaped rock as it prepares to collect samples for return to Earth. Our first guest is the manager of the Hayabusa mission. Junichiro Kawaguchi will join us from his homeland. Then we'll get the personal insights of planetary scientist

and former director of the Jet Propulsion Lab, Bruce Murray. Bruce has been close to the Japanese space effort for many years. That other Bruce, our own Dr. Betts, is back with an artsy space trivia contest for you, along with his report on the night sky, and we'll be getting to Emily Lakdawalla in just a minute or two. Speaking of Emily, we'll give her the top spot in this week's review of space headlines. Check out her update on what we're learning about Saturn's beautiful and fascinating rings. They're turning out to be far more complex than anyone imagined. Emily's full report from the Annual Division of Planetary Sciences meeting in England

is at planetary.org. As we finish preparing this week's show, NASA has scheduled a press conference to describe what they only describe as interesting changes observed by the Mars Global Surveyor above the Red Planet. We're as curious as you are, and we hope to have details next week. The Senate approved the space agency's budget as part of a much bigger spending package. This version included a $200 million increase for NASA. And the Planetary Society has announced the recipients of its most prestigious awards.

Beloved science fiction author Ray Bradbury is getting the Thomas O. Payne Award for the Advancement of Human Exploration of Mars, while filmmaker James Cameron will receive the inaugural Cosmos Award for Outstanding Public Presentation of Science. The pair will be the guests of honor at the Society's banquet celebrating its 25th anniversary in November. That's no oxymoron, That's a volcano made of ice. Here's Emily to tell us more. I'll be right back with Junichiro Kawaguchi. Hi, I'm Emily Lakdawalla with questions and answers.

A listener asked, what is cryovolcanism? From Latin word roots, you can tell that cryovolcanism means volcanic activity involving ice. This seems contradictory, but on worlds as cold as Titan and Enceladus, ordinary water ice is as solid and unlikely to melt as rock is on Earth. But just as geologic activity can melt rock in some places below Earth's surface, so too does geology act to create pockets of cryomagma on the icy moons. When the cryomagma erupts, it's called cryolava. The cryolava would spill out of a vent and form characteristic volcanic landforms, domes and flows and vents.

Features like these have already been observed on Titan. What could be causing Titan's cryovolcanic activity? Stay tuned to Planetary Radio to find out. The little probe was christened Hayabusa shortly after its 2003 launch. The Japanese word means peregrine falcon. It's an apt name for a bird that will figuratively swoop down on asteroid Itokawa, fire projectiles that will send bits of space rock flying into waiting receptacles, and then return these first-ever samples to Earth.

The first objective was reached last week, as the ion-engine-powered spacecraft pulled within 20 kilometers of the asteroid. Project manager Junichiro Kawaguchi and his relatively small team are now surveying Itokawa, looking for safe spots for what will be more of a docking maneuver than a landing. We talked to him just a few days ago. Dr. Kawaguchi, first of all, thank you very much for joining us on Planetary Radio. Not at all.

You must be very proud. You certainly have a right to be. Your spacecraft, Hayabusa, for which you are the project manager, has reached its destination. Right, okay. But the spacecraft, you know, they successfully, you know, arrived at an asteroid, the biggest step, you know, for that project, which we have aimed at.

And now that the spacecraft and the project starts and the observations, our proximity observations, and we are very excited to have that. You are only 20 kilometers from Itokawa. Yes, that's correct.

We intended to make the spacecraft hover at the distance of 20 kilometers first. That's another what we call gate position. And followed by the lower altitude box, that's another home position box, located at 7 kilometers toward Earth's direction, and that will happen next month. The mission is far from over. You have many events still to come,

but for now, you begin a process of observing the asteroid, and part of this is to decide where you will draw your samples from. We are really interested in where to collect the samples from which point. However, still the distance is 20 kilometers, and the resolution is not high. So the only thing we can have currently is looking flat on the plane on the surface but it looks like every point has a boulder and the slope is relatively steep so we may have some difficulty finding a good place at a distance of 20 kilometers. So you have to find a fairly flat area, a flat plane, as you said,

to safely collect these samples. Right. The biggest difficulty in making the spacecraft descend to the asteroid is in how accurately we can guide the spacecraft to that intended point. Through speed and maneuver, that means that we cannot tell exactly which direction the spacecraft starts to descend. So that the dispersion may be

a little bit large. The asteroid is just 450 meters in width, but the dispersion may be several tens of meters. We want to have a wide area which should be in the front, but that area may not be found.

So you will obviously be able to pick the site, but I know that Hayabusa is a very smart, a very intelligent spacecraft that has done some autonomous navigation. Will it be on its own to a degree as it approaches the asteroid later this year? Touching down, of course, in November, almost two months ahead. And by that time, almost for one and a half months, we will concentrate our activity to the mapping activity, based on which we can decide where to land and where to collect

samples. The spacecraft is equipped with a kind of a sophisticated intelligent function to guide itself to target marker, which is illuminated by the flash lamp on board. So every one second, the spacecraft makes a flash lamp on, and the spacecraft identifies where the target marker is, and the spacecraft approaches to that target marker. That's a brief description about how we can make the spacecraft land. I see. And you'll actually, I suppose it's in November, as you said,

that there will be, you hope, two touchdowns to collect these samples. Right, two times. This craft has three target markers as well as three projectiles, well, three guns. However, we think currently the sampling should be two times, preceded by one rehearsal descent without touching down. The purpose of rehearsal descent is to make sure that the onboard navigation system functions and also that we can find out the laser rangefinder aboard should function. This reminds me a bit of

some of the Apollo missions, particularly Apollo 10, just before the moon landing of Apollo 11. The astronauts who came very close to the moon but didn't get to land. Your approach to Itokawa, of course, I suppose should be easier in some ways in that Itokawa doesn't have much of an influence with gravity on your spacecraft, does it? Yeah, that's a good question. You know, touching down and landing on the bigger and the huger planet requires a tremendous amount of fuel.

You know, that requires the biggest thrust and propulsion. From that point of view, those spacecraft must carry the fuel bigger than the propulsion system. craft must carry a fuel bigger than the propulsion system. Instead, landing on this is a kind of docking space station, space shuttle.

More like the space station, yes. However, even though the gravity is very small, ultra-small, almost 10 to the minus 4 of 10 to the minus 5 G, but very enough, you small, almost 10 to the minus 4 of 10 to the minus 5 G. But then very enough, you know, so that's the big gravity, enough gravity, so that we have to take seriously into that gravity into account.

I see. So once these samples are picked up, in December, Hayabusa will leave Itokawa to return with them to Earth and arrives back here in 2007. Yes. In June of 2007, our plan is to make the re-entry capsule land in the desert over in Australia in the south hemisphere. in the south hemisphere. Originally, you know, when our target was a different asteroid, our recovery area was planned in the Utah desert area, where the Genesis and Stardust are going to use.

But currently, from Itokawa, the return trajectory may not plunge into the north hemisphere. The south hemisphere is only a choice. Yes, I see. And so that's expected in June of 2007, and there is a small reentry capsule that will descend with a parachute? Yes, that's right. The spacecraft separates, and that full diameter of about 400 millimeters, that weighs about 20 kilograms,

and the Zatu is released almost in the middle of the moon's distance, and almost 10 hours before the re-entry, and only the capsule plunges into the atmosphere and lands in the desert. And if all goes well, you will have returned about how much material from asteroid Itokawa? not a powder, that should be another kind of the bulk, not the fragments. And that's not very enough for many researchers to analyze. Dr. Kabaguchi, we certainly once again congratulate you and the entire team behind Hayabusa on this first very impressive success. And we wish you the best of luck for the ambitious effort that remains,

this approach to asteroid Itokawa, the collection of the samples. And then we will hope for a safe return to Earth, along with you and many others. Thank you very much. And we think the TPS will continue to support us. Well, we are certainly happy to do that. support us. Well, we are certainly happy to do that. The Planetary Society is certainly impressed and very pleased to provide this coverage of your mission. We will refer people to the article on our website at planetary.org, which should be available by the time people get to hear this interview. We're going to take a quick break and then come back with Dr. Bruce Murray, your colleague,

the former director of the Jet Propulsion Laboratory, who is someone else who is very excited about Hayabusa, which has now reached asteroid Itokawa. Once again, Dr. Junichiro Kawaguchi, thanks for joining us. Yeah, not at all. Thank you very much. We'll be right back.

This is Buzz Aldrin. When I walked on the moon, I knew it was just the beginning of humankind's great adventure in the solar system. That's why I'm a member of the Planetary Society, the world's largest space interest group. The Planetary Society is helping to explore Mars. We're tracking near-Earth asteroids and comets. We sponsor the search for life on other worlds. And we're building the first ever solar sail.

We didn't just build it. We attempted to put that first solar sail in orbit, and we're going to try again. You can read about all our exciting projects and get the latest space exploration news in depth at the Society's exciting and informative website, planetary.org. You can also preview our full-color magazine, The Planetary Report. It's just one of our many member benefits. Want to learn more? Call us at 1-877-PLANETS. Planetary Scientists and Geologists Bruce Murray has seen many milestones reached in our exploration of the solar system,

but few of those milestones were reached by his colleagues and friends in Japan. That has changed in the last weeks, as the former director of the Jet Propulsion Lab and co-founder of the Planetary Society has witnessed and applauded the success of the Hayabusa mission. Bruce Murray, I'm not surprised to know that you've taken a professional interest in Hayabusa and the work of the Institute of Space and Astronautical Science, now part of JAXA, the Japanese space agency. What I did not know is that you have a personal relationship, a personal interest in their efforts.

That's true. It started about ten years ago. My wife and I, Suzanne, started making repeated visits there almost every summer, and they, at that time, were just going into planetary science, and they looked upon me as an asset in that regard. And then we developed strong personal relationships with a variety of people there and vice versa. So it's a warm and trusted relationship with all concerned. Well, and as a planetary scientist of some renown, you must be quite excited about this mission to return a sample from an asteroid.

Yes, because especially I've seen it develop, and I've seen their previous ones, which sometimes they had some failures, and I know how thin they are. By comparison, JPL's effective workforce is, not including the contractor ones, but the JPL employees, about 4,000 people. Comparably there, it's 400 at JAXA. In addition, this same organization develops rockets, which JPL used to do but does not do. They use other people's rockets. So they have done a lot, and that's been their tradition. They're a lot like JPL was in the early days, the late 50s and 60s,

where JPL also developed rockets and launched the first deep space probes and so forth. So there's a lot of similarity in that level, at least. And so I find that fascinating, and it's also interesting to see how two different cultures have responded to the same natural challenges that are involved. So obviously an organization that small, with a mission that is this successful, or at least this successful on an incremental basis, it's a pretty impressive accomplishment.

Exactly, and that is my point. The earlier ones did fail. They had a number of failures. Since they don't manage to popularize either their failures or their successes very well, you probably don't know much about it. But I know how hard they worked and how disappointing those figures were, but it's the necessary steps, and they have elected to kind of go it alone or go it their own way. They do use some U.S. equipment, but not really.

In other words, they've elected to develop their own launch vehicle capability and their own deep space capability. launch vehicle capability, and their own deep space capability. So they're competing with the U.S., they're competing with Europe and the United States. So if you look at the size of the relative space program, their space program in terms of expenditures is quite small compared to the U.S. or Europe, even though the gross national products are comparable. Now, as you say, the program that is in competition with the United States and the European Space Agency programs, I'm sure that they also complement each other and that this mission is one that is welcomed by planetary scientists like yourself

and others here in the U.S. and around the world. Right, and the same thing is true for European missions that are in competition or Soviet or Russian missions. Of course they are. And the other thing is that the Japanese, of course, have been careful to choose missions that they had a good chance of making a unique contribution in and not, for example, they haven't done any Mars missions yet. So they've chosen things that they could do within their capability that were scientifically

interesting and important, but were not duplicative of what the United States or other countries have done. As we have just a minute or two left, I just want to get your thoughts about, or your feelings, in a sense, about this possibility of returning pristine asteroid material directly from space. Right. It's the best and the worst of times in the sense that it is the most important scientific observation that one can make. It's bringing back samples. There's just no question. The power of terrestrial laboratories are so great, and the ability to compare with meteorites and terrestrial rocks,

and also lunar rocks is so great that the significance, you can hardly overestimate it. On the other hand, to complement that, it is the most difficult mission to do, to actually acquire, go all the way out, get down on the surface, acquire the sample, leave the surface, fly all the way back, and then reenter through the Earth's atmosphere successfully. That is really tough. And so they are trying the most difficult planetary mission category that you can do. We'll see how it works. The odds are, in my view, that it probably won't. I mean, not all those steps. But wisely, they are doing some important science along the way, which means that if there is a failure later on,

they will have already made some important accomplishments, which is what's happening right now. Well, we finished with Dr. Kawaguchi by wishing them luck, and we'll give you the chance to do the same before we close out this segment of Planetary Radio. Yes, I have already talked to him and wished them luck based upon my somewhat detailed knowledge of them and what they're doing, as well as my knowledge of the challenge,

and that if this succeeds, it will be an extraordinary achievement on any scale, and for a country with as small and relatively early planetary programming as there, it will be quite extraordinary. Bruce, thanks so much for taking a couple of minutes for us on the radio. Good. Glad to help. Bye-bye. Bruce Murray is Professor Emeritus, Planetary Science at Caltech, and, of course, the longtime past director of the Jet Propulsion Laboratory near Pasadena, California. And the co-founder of the Planetary Society.

And the co-founder of the Planetary Society. Which is equally important to the other two. Lest we forget. Glad you feel that way, Bruce. Thanks again. We're going to be right back after this return visit from Emily with Bruce Betts in this week's edition of What's Up. I'm Emily Lakdawalla, back with Q&A.

What could be generating the heat necessary to cause cryovolcanism on Titan and Enceladus? These bodies are very small, so small that they've likely lost any significant amount of heat left over from their formation. The usual heat source cited for moons of giant planets is tidal heating, cited for moons of giant planets is tidal heating, frictional heat caused by the motions of tidal bulges raised by the interaction between the moon, its planet, and its neighboring moons. But for Enceladus especially, the math doesn't work. Tidal heating can't produce enough energy to make the moon active today. One thing that could help is if the ice on these moons were not pure water ice, but were instead contaminated by ammonia, a chemical that would likely have been present when the moons were forming.

In the presence of ammonia, ordinary water ice displays unusual behavior. It melts at much lower temperatures. If there were a lot of ammonia present, then any melting water ice would necessarily include around 10 to 30 percent ammonia and would become more viscous, goopy rather than runny. A goopy cryolava could create volcanic landforms on Titan that look a lot like the ones we've seen on Earth and Venus. Ammonia water volcanism is a very attractive explanation for volcanism on Enceladus and Titan. The problem is no ammonia has yet been detected at either place. Got a question about the universe?

Send it to us at planetaryradio at planetary.org. And now here's Matt with more Planetary Radio. Time for What's Up on Planetary Radio. Bruce Batts is here. He's the director of projects for the Planetary Society. And he's going to tell us what's going on in the night sky. And I bet he'll have a new trivia contest, too. Won't he? Oh, yeah.

Yeah, I'll think about that. In the meantime, hey. Really didn't. Hey, go out and look up in the sky and see planets. We've got Venus still in the evening. That bright-looking star-like object is Venus. You may still be able to catch Jupiter below Venus, very low down, but it's going to be tough. We've got Mars, however, rising before 10 p.m. in the east, looking beautiful and bright and orange

and just getting brighter over the next couple months. And if you're up before dawn, which I don't suggest, then Saturn is low in the east before dawn. And always a great telescope object, but it'll get better and easier to see over the coming months, so don't worry. On to this week in space history. Two of the great things in space history ever to happen, of course, this week. In 1962, we had the premiere of the Jetsons. Oh, yeah. We got a real cartoon thing going on.

No, not cartoon. TV science fiction thing. Yeah, it's really, it's for you, Matt. Last week, Lost in Space. Now, The Jetsons. Redsons. Astro. Rastro.

Rory Rorge. Didn't we figure out that Astro is like the grandchild to the nth of Scooby-Doo? That's right. Sorry. Ro-ve-ro-ro! Ro-ve-ro-ro-ro! Moving right along to the arrival, no humor here, the arrival of Wernher von Braun to the United States 60 years ago in 1945 after his stint launching missiles at the UK. He decided to come on.

Well, he was persuaded to come on over and eventually help the United States space program get to the moon. We could get some humor out of that, but we won't go there. We choose not to. But don't worry. There's more humor to come. On to Random Space Fact! we choose not to but don't worry there's more humor to come on to random space fact especially nice oh thank you asteroids restroids the largest asteroid in the asteroid belt series has about 25 of the mass of the entire asteroid belt. Wow. I didn't know that. And there's cool new data from Hubble about Ceres and its roundness and its water iciness.

So if you want to find out about that, go to planetary.org, the source of all wonderful information. Well, okay, not all, but there's good stuff there. Let's move on to the trivia contest. Now, we asked you, as of September 7, 2005, how many Progress supply ships, how many of them had visited the International Space Station? How did we do, Matt? Almost everybody got it right. Almost everybody understood that you were talking about the ships that had arrived to that date,

up until the 7th. Right-o. With all those goodies for the astronaut and the cosmonaut. Our winner, Derek Buckley. Derek from Spokane, Washington, said, must be referring to the upcoming 19th. He's going to do some quick math, he says, and say 18 have visited the International Space Station so far. Correct? That is quite correct.

And he will get a fabulous Planetary Radio t-shirt. And indeed, a 19th launched and is now stuck to the side of the space station. I mean, intentionally. Not accidentally. Alright, well let's go on to the next trivia contest. And I thought it was time to delve into the world of fine art. Or at least art. We need to class the place up.

We do. And so, you think I kid, but I'm going to class the place up. Now I'm frightened. We'll need an air freshener. What is the name of the famous tapestry that depicts, among other things, the view of Halley's Comet in 1066 A.D.? Excellent question. I remember this.

From the U.K. From the U.K. For what is now the U.K. I might know the answer to this. Don't say it! I'm not eligible. Tell the people who are how they can enter. Go to planetary.org slash radio.

Follow the links for trivia contests. Find out how to enter and send us your answer to try to be randomly selected from the correct answers to win a Planetary Radio t-shirt. You're going to want to get that entry to us by Monday, September 26th at 2 p.m. Pacific time. Monday the 26th at 2 p.m. Pacific time. And I can't remember if it was in one of my art history books or in my astronomy book, but it's out there, folks. And, you know, before people correct me, it's referred to, its name, its title, even uses the word tapestry, but apparently it is actually an embroidery.

Oh. So all of those into such things. Don't worry. You took art history, too? Yeah, but not for that. Because there was a lot of girls in that. I know. He's got no comeback.

Wow, I'm actually speechless. Two and a half years of the show. I'm not sure that's ever happened. I don't think it has. Well, are we done? We are done. I'm sorry. I know that's my job.

Bruce, we're done. Oh, thank you. Well, everybody, go out there, look up in the night sky, and think about Ruby Snacks. Right, right. Ruby Snacks. Ruby, do, do, do. He's Bruce Betts. He's the director of projects for the Planetary Society.

He joins us each week here on What's Up. Good boy. Right. Good right. Planetary Radio is produced by the Planetary Society in Pasadena, California, where we welcome our newest listeners, catching us for the first time on KWRP, free-form radio for beautiful Santa Fe, New Mexico.

We hope you enjoy our little space opera. Got any questions about the universe? Send them to planetaryradio at planetary.org, and we'll pass them right along to Emily for her Q&A segment. Have a great week, everyone.