Planetary Radio: Space Exploration, Astronomy and Science - Planetary Society Executive Director Lou Friedman on solar sails IKAROS and LightSail-1

Episode Date: May 17, 2010

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Two, count them, two solar sails, 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. Planetary Society Executive Director Lou Friedman returns with an update on the Society's ambitious solar sail project, LightSail. But Lou also has news about another solar sail that may be in space as you hear this. Japan's innovative Icarus will piggyback into deep space on top of a Venus probe. Emily Lakdawalla has a hopeful report on another deep space traveler.

Troubled Voyager 2 is in the virtual repair shop, even as it shoots past the edge of our solar system. And Bruce Betts will once again get lost in space with me as we present What's Up, a new trivia contest, and try the first ever unplugged version of Random Space Fact. Bill Nye is in Connecticut this week. The science and planetary guy was the immensely popular commencement speaker for Quinnipiac University. He'll be back with a new commentary next time. Emily is ready to review the best of the Planetary Society blog. Ms. Lakdawalla is the Society's Science and Technology Coordinator.

Emily, first, hearkening back to last week's conversation, I want to congratulate you. Your Martian moment in time not only made it onto that New York Times blog, but got some nice comments. It really did. I think people appreciated realizing that there are moments of time all over the solar system, not just here on Earth. Let's go on to something that is maybe not even quite in our solar system anymore. I guess it is, really. And that's Voyager 2, which has run into some trouble. And you went to the boss, Ed Stone, to find out what's going on. Yeah, they had some trouble with Voyager 2 earlier this week. It started sending back basically nonsense data. You know, this is very worrisome for a spacecraft that is 13 light hours from Earth. But they pretty quickly zeroed in on what they think is the problem. They think that there is a flipped

bit somewhere in its flight data system because they were able to successfully command Voyager into a mode where it just sends back engineering data. And so the spacecraft is responding to commands. And when it was put into that mode, it behaved just fine. It just can't format its science data properly. They've instructed Voyager 2 to send back every last bit of the software that's currently residing in its flight data system. And they're going to look at all of the bits, figure out which one is wrong, and then figure out what to do to fix it. Well, hopefully for a spacecraft that old, there aren't too many bits in total to look at. But it's interesting the comparison between this and a biological mutation.

That's right. Well, it's amazing how much havoc one flipped bit can cause. Well, it depends on where in the code the mutation or the flipped bit happens. It can happen in a relatively innocuous location. You just notice because it looks like there's a bad bit of data. But if it happens in an important place in the software, then suddenly the spacecraft isn't talking sense to you anymore, which is what happened. But they're pretty confident they can fix the problem. What has been the public reaction that you've gotten to this, at least from your readers? Well, I think a lot of my readers feel the

same way I do, which is that Voyager 2 is probably the most beloved unmanned mission out there. It was the first surveyor of so many new and distant lands. It's the one that has boldly gone where no one has gone before, and it's still going. And, you know, Voyager 2 is going to have to die one of these days, but I'm sure glad it doesn't seem to be now. You bet. Interesting that you said you could segue from this to a story that has gotten an enormous amount of attention for a planetary science development. That's on Jupiter. That's right. Well, Jupiter is one of the most dynamic places in the solar system.

As we knew before Voyager went by, Voyager was the first to return movies that show how the clouds move around on Jupiter. As seen through a small telescope, Jupiter is usually a disk with two dark bands running across it. And now if you were to take a small telescope and point it at Jupiter, one of those bands would be missing. Now it just has one band. It's kind of surprising. It's the south equatorial belt that has turned from red to white. But evidently this is not an uncommon thing.

It happens pretty regularly. In fact, Jupiter looks now kind of like it did to the pioneers when they flew past. And it's something that happens every 3 to 15 years. Absolutely fascinating. Speaking of this planet that was first really revealed to us in great detail by the Voyager spacecraft. Emily, thanks a lot. We'll talk to you again next week.

All right, Matt. Thanks for having me. Emily Lakawala is the Science and Technology Coordinator for the Planetary Society and a contributing editor to Sky and Telescope magazine. Back with Lou Friedman in just a moment. Lou Friedman has run the Planetary Society for more than 30 years, but he has been in love with solar sailing for much longer than that. He first came to understand the almost limitless potential of sailing on the light of the sun while he was with the Jet Propulsion Lab

back in the 70s. His book, Star Sailing, was published in 1988. Lou believes sails are still the only practical technology humans have come up with that could get a spacecraft to other stars. The Society's executive director recently announced his intent to retire this year, but his involvement with the LightSail project will continue. Lou also headed the Society's earlier attempt to fly the first solar sail. Sadly, Cosmos 1 never made it to orbit. Its Russian submarine-launched rocket failed. Even this did not dim Lou's enthusiasm.

I sat down with him a few days ago in the library of the Planetary Society's new home in Pasadena. Lou, it's good to have you back at the Planetary Radio Microphones, and we'll be doing other stuff that'll be available on the web as well today at planetary.org. A topic we've talked about many times, though, solar sails. And it used to be that we only talked about the effort being made by this organization, the two-head. But I guess we'll start talking about one that, if all goes well, may be launching imminently. Yes, indeed. I'm very happy to be here, Matt. I always love to talk about solar sailing and always love to talk on planetary radio. Indeed, Icarus is about to launch a Japanese mission to test out a really novel concept.

I admire the Japanese. They're doing a rather grandiose technology test. They're testing solar power generation inside a solar sail, and the ultimate goal is to develop a hybrid, which seems appropriate these days when we think about energy sources for transportation. They want to develop a solar-powered spacecraft that also uses solar sailing to do outer planets missions. And this first mission that they're doing, this Icarus mission, is testing out the thin-film solar sail that will also be used for solar cells to generate power. If they succeed in everything they want to do, they will actually fly a solar sail flight, the first solar sail flight. So we're wishing them great success in this.

They'll deploy on their way to Venus. them a great success in this. They'll deploy on their way to Venus. They're piggybacking a ride to Venus on the Akatsuki mission. That's a Venus climate orbiter, and they're very lucky. They can act, being a space agency, they can do something we can't do, which is piggyback on side a mission that's going out into interplanetary space. Planetary Society members and those who've seen me write about solar sailing for years always have heard me give the terrestrial analogy, sailing boat analogy. You don't really want to put your sails up in the harbor. You want to be out there in the open ocean sailing with the wind. And the analogy in space is you don't really want to use sails in Earth orbit.

That's where you have to get them to start. But you really would like to be flying on interplanetary space, where you could have the light behind you all the time. And indeed, that's what the Japanese spacecraft is going to do. They're piggybacking a ride on an interplanetary mission to Venus. They're going to be deploying their solar sail, which is some 20 meters by 20 meters in size, a fairly large one. But their spacecraft is very heavy because it's such a technology testing. They've thrown everything into this technology test. They have a 350-kilogram spacecraft.

And if you remember, Cosmos 1 was 100 kilograms. And our light sail is 5 kilograms. Oh, my goodness. So it's a huge difference in scale. Our light sail will be faster than their vehicle, even though they have this wonderful technology test, because our low mass will give us a higher acceleration, and we'll have a very fast vehicle,

because we're trying to do something different. Japanese, having a space agency's power behind them are doing technology tests of all kinds of exotic things that I'm very envious about on the one hand, but it also would be a digression for us. We want to fly pure solar sailing. And so our five kilogram light sail spacecraft will be a step toward that pure solar sail vehicle of the future. Theirs will be a test of a hybrid vehicle of the future that might be more of a workhorse for interplanetary travel. We're going to talk much more about light sail, but I want to come

back to this thought that this is both driven through space by solar energy, in a sense, and generating it. And you've about the thin-film solar cells. This is actually part of the material of the sail on Icarus? Oh, it's even better than that. Yes, it is part of the material on the solar sail. Of course, a little thicker in the spots there, but, you know, so they will get, there'll be real solar cells embedded in the material.

And then they have the ability to control the albedo of different cells. So they can actually change the, they can use that for attitude control because they can make one side of the sail a little darker than the other. They can get a differential light pressure and thereby actually point the sail or tilt the sail. So they electronically steer the sail if this works. Right. Wow, that is fascinating. It is fascinating, and as I say, I'm envious in many ways because it's the kind of thing NASA should be doing and the Europeans should be doing and the Russians should have done in their buildup of these technologies.

But it seems like the Japanese are a little more able to be flexible about doing a technology test in a piggyback mode on this spacecraft. Come back to talking about your analogy to putting the sails up in the harbor. I remember when we were working on Cosmos 1, the much bigger, earlier version of a Planetary Society sail, that there were real questions about being able to navigate that in low Earth orbit. I mean, it's a pretty complex problem, isn't it? It is.

Again, for those of you who sail boats on Earth, you know that tacking in a harbor or in a channel can be a pretty tricky business. The analogy for us in Earth orbit is we have to keep tilting the sail so that the sun is reflecting off the sail as we go around the Earth, and we never have the sail force being actually opposed so that we would fall in toward the Earth. We always want to be increasing our velocity in Earth orbit. So, yes, we have a tricky navigation job, somewhat harder than if you would an interplanetary travel where the sun direction is more or less constant, at least over days and weeks. So therefore, you have a much easier,

slower turning rate that you have to do when you want to control the direction of the sail. But unfortunately, we live in a gravity well. Every day I wake up and I realize, oh my gosh, another day in the gravity well. I went to the doctor and he says, why do you have all those aches and pains, I ask him. And he says, because we live on this heavy planet. If we lived in space, we wouldn't have so many aches and pains. This is the answer to health care. This is, I mean, and not only is it a pain for me personally, but it's a pain for my solar sail vehicle, which has to get off the Earth. And this has been the big impediment. We have to get off the Earth in a heavy rocket,

and then we have to work in the Earth orbit in order to slowly spiral our way away from Earth and get into deep space. Access to space is a big issue. It's a big issue for our physiology, as well as being a big issue for our test vehicles. It's a little early, as we said, to wish them, to congratulate them, I should say. I hope by the time this show airs that we are congratulating them. I was asked in an interview last week whether I feel some competition because we want to be the first solar sail flight. And yes, of course, we want to be the first solar sail flight.

We want to be the best at whatever we do. Yes, of course, we want to be the first solar sail flight. We want to be the best at whatever we do. But the real purpose of all Planetary Society projects and all what we're trying to do is advance space travel and advance a new technology that will enable new kinds of space travel in the future. If they succeed in this mission and then we fly our mission later this year or next year, and we succeed in a very different type of vehicle, a pure solar sail at 5 kilogram total weight. We are both advancing it in a big way. And so I think in the sense of advancement of our objectives, we wish them all the best of luck. Of course, the launch is a major milestone, but the deployment of the sail is

the trickiest of the milestones, and then getting it all to work right. You know, there have been tests of solar sails in space before, including by the Japanese, that haven't worked. They've gotten wrapped up a little bit on the deployment. There's never been a flight yet of a solar sail, but even some of the deployment tests have had these impediments. It's a tricky business, and we're wishing them all the best of luck. I'll be back with Lou Friedman and more about solar sails Icarus and LightSail 1. This is Planetary Radio. I'm Robert Picardo. I traveled across the galaxy as the doctor in Star Trek Voyager. Then I joined the Planetary Society to become part of the real adventure of space exploration.

The Society fights for missions that unveil the secrets of the solar system. It searches for other intelligences in the universe, and it built the first solar sail. It also shares the wonder through this radio show, its website, and other exciting projects that reach around the globe. I'm proud to be part of this greatest of all voyages,

and I hope you'll consider joining us. 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. Our nearly 100,000 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. The first test of actual solar sails is imminent, according to our guest. Lou Friedman is the executive director of the Planetary Society and a longtime booster of solar sailing. He usually reports to us on the progress of the Society's LightSail1 mission, but this time he is also sharing his excitement about Icarus, the ambitious Japanese sail that may have been launched toward Venus by the time you hear this.

And they're not deploying right away. I mean, it's going to be a while. Yes, it'll be several weeks. Well, they don't know yet exactly. They'll check out a lot of things on the spacecraft, but it'll be more than a few weeks. But it won't be many months either, because they want to do it somewhat near the Earth for better communications and better visibility of being able to image. LightSail 1, and you just said you're still looking at, the whole team that you head is looking at,

late this year or sometime next year? Yes, I think we're going to be ready before our launch vehicle, which is unfortunately, if you heard my earlier remarks, too often the case in space travel. It was true when I first worked on solar sails back at JPL back in the 70s. We thought we were audacious in proposing a very large solar sail to go to Halley's Comet, but we had a launch on the shuttle. Turned out the shuttle wouldn't have been ready in time. It didn't matter what we did with our spacecraft. I think in light sail, we will complete our spacecraft work this year, or at least we could, but the launch opportunity may be slipping into 2011, and maybe even, we're just not sure. It won't go later than 2011, but I mean, it won't go at the beginning necessarily either. So we're now looking very

hard at the launch manifest. We're talking to launch vehicle providers. NASA's being terrific. We have a space act agreement with NASA Ames. We share the technical results of our project and they're helping interface with the launch vehicle people. We hope to get a launch pinned down pretty soon. It's absolutely necessary that we do know what our launch vehicle is. As far as our spacecraft development goes, we're headed up toward a critical design review in a couple of weeks. If we get through that critical design review well, we will freeze what we call freeze the design. No more arguing about which component is better or which way to do something. Just build it.

And so we're anxious, of course, to get to that stage. Let's remind people who can certainly go to the website, planetary.org, and there's a lot of information about light sail there, but they might also see images of the old Cosmos 1 design. This is a very different spacecraft. Well, it's very different. Of course, I like to say that the car hasn't changed in 150 years. They all have four wheels and an engine and a steering wheel.

You know, the cars look the same now as they did in the year 1900, as far as I'm concerned. This, too, about the solar sail. It's a large, thin, kite-like-looking structure with a central hub where the electronics are, where the brain is. You're not going to get away from that. That's going to be the architecture. So, yes, this is very different than Cosmos 1, but it's still a very small 10-by-10-by-30-centimeter hub, three CubeSats put together in a rectangular configuration. And CubeSats are the 10-centimeter-by-10-centimeter-by-10-centimeter boxes

that a lot of universities are working with to put stuff up in orbit. That's right. And we're elaborating on those, building basically one of those up to handle all our electronics and building two more of them to house the solar sail module. The solar sail module will deploy itself into a five.5 by 5.5 meter square area. And that's pretty big. That's impressively large, even though it's much smaller than the size we had with the 15 meter Cosmos 1 radius of the sail, or 30 meter diameter that we had there. It's a medium-sized living room, I guess, as you might...

I think it's larger. It's a large-sized room, very large-sized room. And as I say, that area, 32 square meters, divided by 4.5 kilograms of spacecraft mass, gives you a characteristic acceleration, which will be faster than Cosmos 1, faster than Icarus, faster than NASA's NanoSail, faster than any vehicle that's ever been built to do solar sailing. So we have a speed demon, if this all works.

I hope so. I hope we are the, what is it? Well, I hope we're fast. Of course, the trick will be to harness that energy and that power and that acceleration to control it. And that's what we have to prove. That's the big challenge for solar sailing now. Everybody knows the theory is correct, but they don't know whether you can practically control it. I used to hear jokes about aircraft engineers who would say, I know the airplane works, but I don't understand aerodynamics. And I can't believe

when I'm sitting in the airplane on the runway that this thing is just going to roll down there and start going up in the air. How does that happen? It is kind of like that with the solar sail. We know the theory, but actually practically doing it and seeing it fly is going to be a really big deal. Lou, we'll check back with you again. Maybe sometime after those engineering plans are locked down, you said, in a matter of weeks. Well, check with me about LightSail 1 in a couple of weeks, and I hope to be back and tell you how the Icarus deployment went in a few weeks, too. Thank you very much, Lou.

Lou Friedman is the executive director of the Planetary Society. He joins us periodically here on Planetary Radio. And we'll be joined in a couple of moments by Bruce Betts for this week's edition of What's Up. We've got Bruce Betts here with us. He's the director of projects for the Planetary Society. And we are in, what is this, the library? It's the Matt Kaplan Memorial Library. Here in the new headquarters of the Planetary Society. And it's up to the listeners to figure out how he was done in.

With the lead pipe? I think the butler did it. Or maybe it was Colonel Mustard. Yes, definitely. It's always Colonel Mustard. What's up? Hey, we got the night sky. Venus, the easy thing to see over in the west after sunset.

Looking like a super bright star-like object. But also check out Mars above that and Saturn above that and if you're having trouble finding these I got a way to help you. I've arranged for the moon to go past these objects and so on May 19th the moon will be near Mars that's the reddish thing near it and on May 22nd near Saturn. Now the Saturn thing if you check out Saturn with a telescope, which probably that's not the best time to do it when the moon's right next door, Saturn's got the rings about as edge-on as they're going to get for the next 15 years.

Just like a knife edge. Ow. Also, you can almost always check out Titan, its large moon, looking like a tiny star off to one side or the other. That moves us on to, oh, the pre-dawn. Don't want to forget super bright Jupiter over in the east. Can't miss it, if you're conscious. On to this week in space history. Apollo 10 launched and went oh so close to the lunar surface in 1969 during this week.

Oh, so tempting. Tempting, but don't go there. Do you remember how high they were above the lunar surface before they came back? In English units, 50,000 feet. Oh, gosh, can you imagine? Wow, all right. A stone's throw.

Well, maybe not, but with gravity. On to Random Space Fact! Random Space Fact! I don't think this room has ever had quite that experience until now. It has a nice and inherent echo. Yeah. Going back to, what, the 20s or 30s in this building, I think. That was unique. Moved into a modern building.

Asteroid. The term asteroid. William Herschel. Sir William Herschel. Though not the discoverer of the first asteroid, did suggest the term asteroid, coming from the Greek for star-like, because you have these weird things that were moving across the sky relative to the stars, like planets, but with the equipment of the day,

they couldn't really make out any type of planetary disk. So it was star-like, they went with asteroid. Very interesting, I didn't know that. That's what I'm here for, font of planetary disk. So it was star-like. They went with asteroid. Very interesting. I didn't know that. That's what I'm here for. Font of obscure knowledge. Let us go on to the trivia contest. Speaking of obscure knowledge,

we asked you, what was the first American spacecraft launch following the official beginning of NASA, October 1st, 1958? How'd we do, Matt? It was not our usual response. A little bit on the small side, which just makes the odds better for those who did respond, but a decent response. Of course, this being the first

spacecraft after NACA, I just like to say that, became NASA, the National Aeronautics and Space Administration. It was, according to our winner this week, Pioneer One. Second and most successful, it says, of three Project Able space probes, but not all that successful. Space is hard, they were learning at the hardware. Yes, it was supposed to go off and go to the moon, and it didn't really happen. But this one, as opposed to some of the others, like the little-known Pioneer Zero.

Now, wait. Pioneer Zero actually existed. Yes, there was Pioneer Zero, I believe. And I'm sorry, I'm not sure. We got the Zero after its failure. Ah, okay. Then once there was a second one that had problems, then we just started numbering. Because calling a spacecraft Zero just doesn't seem right.

I'd rather call it 13 than zero. And the big zero, scheduled for lunch today. Yes. All right, let's go on to the... Oh, wait, I do need to say... Oh, you should announce the winner. I certainly... I sointingly...

I sointingly... Etienne. Etienne Fellman. Etienne Fellman, one of our French listeners, not only a first-time winner, but I think this is the first time he's ever entered the contest. And voila. Oh, nice. Etienne, we're going to send you a Planetary Radio t-shirt, so thank you for entering. Now, by the way, you know, Lindsay Dawson, our friend from down under who sends us wonderful entries every week,

Now, by the way, you know, Lindsay Dawson, our friend from down under who sends us wonderful entries every week, he gave us pictures and saw a resemblance, which I'm not exactly sure I see, between Pioneer One and the famous robot from Lost in Space. Danger, danger, Will Robinson. Danger, Will Robinson. Really? I don't think I see it, but maybe they recycled Pioneer One. A little bubble head. Turned it into it. Added a bubble head. Oh, yeah. I they recycled Pioneer One. A little bubble head. Turned it into it.

Added a bubble head. Oh, yeah. I think that was it. It's the bubble head. Flexible arms. By the way, you know that on Lost in Space, the guy who looks like Locke, that's not really Locke. That's the smoke monster. Oh.

Matt? Yeah? I think you got a little confused between your multiple decades apart fiction shows on TV. Okay. But they're both science fiction, right? Sure. Sure they are. Danger, Will Robinson.

It's the smoke monster. Danger, Will Robinson. And we go on to our next trivia contest. Thematically, the Japanese solar sail spacecraft IKAROS. What does IKAROS stand for? Oh, I'd forgotten this was an acronym, and I have actually seen this. It's quite clever.

It is. I mean, obviously they're making a reference as well to Daedalus and IKAROS, the mythological reference, but it is an acronym, an acronym of English words. So go to planetary.org slash radio, find out how to enter, and tell us what the acronym ICARUS, as in the Japanese Solar Sail Spacecraft, what it stands for.

You've got until Monday, May 24, at 2 p.m. Pacific time to get us that answer. You know, I didn't think of this before, but ICARUS, ICARUS, not a name that bodes well for something that hopes to stay up. Yeah, well, yeah, with the whole wings melting thing approaching the sun. We still wish them all the best. But originally it was named Icarus Zero. Okay, not really. Okay, everybody, go out there, look up in the night sky,

and think about wood and what you can do with it. Thank you, and good night. They made very good use of it here in this room. And would I, I would speak forever with Bruce Betts, the director of projects for the Planetary Society, who joins us every week here for What's Up. The Science of Pandora with Avatar creator James Cameron. That's next week on Planetary Radio,

which is produced by the Planetary Society in Pasadena, California and made possible in part by a grant from the Kenneth T. and Eileen L. Norris Foundation. Keep looking up! Редактор субтитров А.Семкин Корректор А.Егорова