Planetary Radio: Space Exploration, Astronomy and Science - Dawn Mission Update and At Home With Marc Rayman

Episode Date: November 19, 2012

Dawn is on its way from Vesta to Ceres, the biggest of the asteroids. Mission Director and Chief Engineer Marc Rayman says all is well, with much more great science to come.Learn more about your ad choices. Visit megaphone.fm/adchoicesSee omnystudio.com/listener for privacy information.See omnystudio.com/listener for privacy information.

At home in space with Mark Raymond of the Dawn Mission, this week on Planetary Radio. Welcome to the travel show that takes you to the final frontier. I'm Matt Kaplan of the Planetary Society. Time for a timely update about the Dawn spacecraft, which recently departed Asteroid Vesta for even bigger series. But this time we'll include a video tour of Mark Raymond's home, which is a living tribute to space exploration. Mark is Dawn's chief engineer and mission director. Everybody else is also on board for this trip across our solar system,

beginning with Emily Lakdawalla. Emily, let's start today with this blog entry that you posted on the 16th of November that has to do with the release of Dawn's data, which actually we thought was happening last January, but apparently not so much. Yeah, so Dawn's data from the Vesta phase of its mission, or at least the beginning part of the Vesta phase of its mission, or at least the beginning part of the Vesta phase, was originally released way early in 2012. But it turns out that that wasn't an authorized release. There is a dispute between the principal investigator and the International Astronomical Union over the choice of coordinate systems for Vesta, which held up

the whole thing for several months. But that's finally been resolved, and now there has been a goodly chunk of the data from Don's mission to Vesta released, and Don's camera is absolutely amazing, so these pictures are really gorgeous. And there is some very nice stuff, a little bit of your own contribution. I like your little rotating Vesta images. Very cute. Yeah, you know, that's one of the easiest things to do with these images is just to stack them and animate them. But what I do when I approach a new data set is I try to make it easier for everybody to get into the images. So I made a couple of index browse pages that show

thumbnails of every image that's released in this data set. And I'm hoping that a lot more people will go in and download them and try to make their own animations and color composites and stuff. And you've got a link to those indexes right here in the blog entry, right? Yes. So now let's go on to someplace else, something I think you're going to be writing about shortly after this conversation. That's right. Hallelujah.

Curiosity has finally started driving again. It's been 40 sols since Curiosity pulled up to Rocknest, where it first started testing the scoop mechanism and put some samples inside its analytical laboratory instruments. And all of that was very necessary and very important. And it was important that they took their time, but I was getting really tired of the view. Curiosity is a rover after all. And so finally, I'm happy to report that Curiosity has roved another, oh, about 20 meters or so and is actually now on the light colored rocks at Glenelg, where pretty soon it's actually going to park again for a little while because it

still has to try out the drill for the first time. Well, that'll be exciting. And then later, it'll continue its trek into them there hills, right? Not just continue, it actually has to turn around and go back whence it came in order to go past there to get started driving toward those hills. So hopefully we'll start seeing that early next year. Great stuff. Thanks so much, Emily. We'll talk to you again soon. You're welcome, Matt. She is the senior editor for the Planetary Society and our planetary evangelist and a contributing editor to Sky and Telescope magazine. That's Emily Lakdawalla. Up next is Bill Nye, once again on the road. Bill, I'm looking at you in a hotel room up in Canada, so you're on the road again. But it's actually a trip from a few days ago that I think you wanted to talk a little bit about,

and not just the trip, but some people you spoke with. Yes, Jennifer Vaughn, our COO at the Planetary Society, and I, the CEO, went to NASA headquarters. And we spoke with Lori Garver, the deputy administrator of NASA. And we also spent quite a bit of time with John Grunsfeld, who's the head of NASA science now. You may remember John Grunsfeld as the guy who repaired the Hubble telescope. Astronaut turned administrator. That's it. Quite an insight about the future of humans in space. For those of you who don't keep up with space news, you know, the astronauts up at the space station were repairing a leak, ammonia,

in the cooling system on the space station. And Grunsfeld was saying, well, that's fine. That's important to do. These people up there spend a lot of time on checklists, and they're very diligent. They're excellent engineers, often very good mechanics, electrical technicians. But what they want is for regular people to go to the space station, regular scientists to go up there and do some, let's call it breakthrough research in zero G or weightlessness. And it's quite an insight. It's that people spend a lot of money putting that thing up there, but they really believe that the best is yet to come. And I mention this because there's all these companies taking you into space right now. Virgin Galactic, Sierra Nevada Corporation, Blue Origin, they want to take

stuff into space. And of course, SpaceX. This movement now is going to enable NASA to go farther and deeper into space. And that's going to be better to go farther and deeper into space, and that's going to be better for all the space agencies around the world. It's really going to be an exciting time. They said, too many checklists. Want to get away from the checklists. Increase reliability, and then we can do some new science. It was really an excellent conversation.

For those of you who are members of the Planetary Society, Excellent conversation. For those of you who are members of the Planetary Society, we are still working hard to make sure this funding for planetary science is not cut. The deal is not done. We are hopeful. And I don't care whether they're members or not. We're still working on that. That's right, yeah. Thank you, Bill. Thank you, Matt. He's Bill Nye, the CEO of the Planetary Society and the science and planetary guy. He'll join us again next week.

Coming up next, a Dawn mission update from Mark Raymond and a video tour of his home. After orbiting Vesta, the second largest of our solar system's asteroids, for just over a year, the Dawn spacecraft has fired up its ion engine and departed for Ceres, the even larger dwarf planet in the asteroid belt between Mars and Jupiter. It's a milestone that's worth celebrating. So I asked Mark Raymond to return to Planetary Radio. Mark directs the Dawn mission and also serves as its chief engineer. We met in person for the first time, and that's why we have a special treat for you. It's a video tour of Mark's home, where he has collected books, files, artwork, and memorabilia

revolving around our exploration of space. You'll also find out why Mark was investigated by the FBI. You'll see his Mongolian space food, and you'll meet Event Horizon, Mark's rescued iguana. It's on the Planetary Society YouTube page, and we've got a link at planetary.org slash radio. Dawn left Vesta on September 5th. And now it's on its long journey through the asteroid belt, headed for Dwarf Planet Ceres, which it will reach in 2015. So it's a long way.

And how is the spacecraft? The spacecraft is doing very well. It's healthy, spending most of its time thrusting with its ion propulsion system, without which this mission would be truly impossible. Talk a little bit about what it takes in terms of navigation and propulsion to get from the second biggest object in the asteroid belt to the biggest object in the asteroid belt. There's a lot going on here. There is.

Again, the spacecraft has to spend most of its time thrusting with its ion propulsion system because it needs to reshape its orbit around the sun. So it started in Vesta's orbit, and it has to end up in an orbit that looks just like Ceres' orbit, which means it has to enlarge this elliptical path around the sun, and it has to tilt its orbit, and, of course, it has to do all of that and wind up not only in the same orbit that Ceres is in, but at the same place that Ceres is in its orbit. Ceres is a bit farther out even than Vesta.

It is. So Vesta's maximum distance from the sun is almost 2.6 times Earth's average distance from the sun. Or astronomical units. Right, astronomical units. And that's about Ceres' minimum distance from the sun. Ceres goes out to almost exactly three astronomical units. So Dawn has quite a climb up what I like to call the solar system hill. The sun is at the bottom of this hill. Earth is one astronomical unit up the hill. And the objective of all this thrusting with the ion propulsion system is to climb still higher up this hill. How complex is the math, are the calculations, the celestial navigation to get you from one place to another? It is very complicated.

Conceptually, it's easy, and much of the basics can be understood with advanced algebra or just introductory calculus, but the details are much more complicated. We account for the gravitational effects of not only the sun, but all of the planets. We account for the effect of sunlight pushing on the spacecraft. Of course, we have to account for the ion propulsion system because it's how we get there, but the spacecraft also has tiny rocket thrusters that use the conventional propellant hydrazine in order to help it rotate.

And every time it fires one of those, that imparts a little bit of additional orbit change to the spacecraft, or I should say causes a little bit of an additional orbit change. So we have to account for myriad effects. And obviously, we're able to do it because NASA sends spacecraft to destinations from inside the orbit of Mercury to far outside the orbit of Pluto. And we always get where we're going. I love taking into account just the force of sunlight itself, because of course, that means that to some small degree, Dawn is a bit of a solar sail.

It is. Well, in fact, all spacecraft are. Dawn, having among the largest solar arrays ever used on a NASA interplanetary spacecraft, is more subject to that than many other spacecraft are. But of course, the Planetary Society is particularly interested in this effect because of its interest in solar sails, which I fervently its way. And it has this beautiful blue-green stream of ions coming out of its rear end, out of that wonderful ion engine. If we were in space, would we actually see that beautiful color? It wouldn't be that bright, but it is visible to the naked eye

if there aren't any other distracting sources. That is, if you didn't have the sun also in your field of view, you can see this pretty blue-green. And the reason for that is xenon just happens to glow blue-green like neon. Its sister element happens to glow orange, which we know from neon lights. Yeah, it's really not much different, is it? They're just a bunch of excited ions. That's exactly right. But the key difference is that they're leaving the spacecraft

at speeds approaching 90,000 miles per hour. And so with the propellant departing at such incredibly high velocity, it imparts a relatively large push back on the spacecraft, and that's why the ion propulsion system is so efficient. And I know it's hard to express this because it's how fast relative to what, but how fast, what's the fastest that Dawn will eventually travel around the solar system? The fastest it ever went was the day it left Earth, because you and I, and I presume most of your listeners,

day it left Earth, because you and I, and I presume most of your listeners, are here on Earth orbiting the Sun at more than or about 30 kilometers per second, so something like 66,000 miles per hour. But the farther we go away from the Sun, the slower objects move because the Sun's gravitational grip is weaker, and so they don't have to move as quickly in order to stay in orbit. And so while dawn is constantly pushing itself with its propulsion system, it actually is slowing down as it climbs outward from the sun. This is just like the space shuttle, space station, and other satellites in low Earth orbit travel well in excess of 17,000 miles per hour. But as their orbits grow larger, and you get out, say, to the distance of the moon, the orbital velocity is much, much lower.

Similarly, we're going out farther from the sun, and so the spacecraft's velocity keeps going down. That's Mark Raymond of the Dawn Mission. He'll tell us more in a minute. This is Planetary Radio. Hey, hey, Bill Nye here, CEO of the Planetary Society, speaking to you from PlanetFest 2012, the celebration of the Mars Science Laboratory rover Curiosity landing on the surface of Mars. This is taking us our next steps in following the water and the search for life, to understand those two deep questions. Where did we come from, and are we alone? This is the most exciting thing that people do.

And together, we can advocate for planetary science and, dare I say it, change the worlds. Hi, this is Emily Lakdawalla of the Planetary Society. We've spent the last year creating an informative, exciting, and beautiful new website. Your place in space is now open for business. You'll find a whole new look with lots of images, great stories, my popular blog, and new blogs from my colleagues and expert guests. And as the world becomes more social, we are too, giving you the

opportunity to join in through Facebook, Google+, Twitter, and much more. It's all at planetary.org. I hope you'll check it out. Welcome back to Planetary Radio. I'm Matt Kaplan, taking you back to the home of Mark Raymond, the Dawn mission director. Dawn is now on its way from No. 2 Vesta towards Ceres, the largest object in the asteroid belt. Remember that you can join me for a very entertaining video tour of Mark's home, including his space room. entertaining video tour of Mark's home, including his space room. It's on the Planetary Society's YouTube page, and we've also got it in the Planetary Society's multimedia section at planetary.org. Let's turn to science, because you have given, you guys who are running the mission, a lot of scientists, an awful lot of science that I suspect they're going to be dealing with for years and years. Well, that's true.

I mean, we've explored an entire alien world. I think most people think of asteroids as sort of little chunks of rock. That's how they're depicted in movies, maybe the size of mountains or buildings. But Vesta is a big place. Its equatorial diameter is 350 miles. It has more than twice the surface area of California. And so it's not just a chunk of rock. It's a mini planet. And so there's a lot to be investigated there. You compared Vesta to our planet, to Earth, and said it's more like Earth

than a lot of other asteroids. That's right. Vesta, for example, has a dense core, just as Earth does. Now, it's not molten, but it's probably made of iron and nickel. It's high density, and surrounding that core is a mantle, and then above that mantle is a crust. So when Vesta formed, it underwent many of the same geological processes that the planet right underneath our feet did. It's different from the typical small asteroids that tend to be pretty much uniform in their interiors. Vesta is not like that. What are some of the other science results that you're most excited about or intrigued by? I think one of the neatest things on Vesta is this extensive system of troughs near the equator. Now, it's believed that these are a scar from a huge impact about a billion years ago that excavated a crater more than 300 miles in diameter.

that excavated a crater more than 300 miles in diameter. And this crater is very near Vesta's south pole. And yet far away, that is near the equator, there's this large system of troughs, some of which run for hundreds of miles. They're perhaps 10 miles across or so in a comparable depth. And it's believed that this giant impact sent such an incredible shock wave through Vesta that it disrupted it this long distance away at the equator. So these are, again, a sort of scar from this huge impact. Surprising it didn't just tear it apart.

It is. It was close to a planet-wrecking impact. It excavated a tremendous amount of material. Perhaps 1% of Vesta's volume sent much of this out into space. And a fair amount of that material then went into their own orbits around the sun. Some of it, of course, fell back to Vesta. But much of it went its own way. And then some of that material made its way to the part of the solar system

where you and I spend most of our time and eventually landed on Earth. You give this an amazing percentage of the meteorites that have been found on Earth that apparently have come from Vesta? That's right. Something like 6% of the meteorites on Earth. I mean, think of this. Perhaps something like one out of every 16 meteorites found on Earth came from that one impact at Vesta. In fact, in the next room here, I have a meteorite that came from Vesta. I think most people know that we have meteorites from Mars.

Many people may know that we have meteorites from the moon. But we have far, far, far more meteorites from Vesta than we do from the moon or Mars. And those are the only three solar system bodies to which we have linked specific meteorites. to which we have linked specific meteorites. Let's go on to Ceres before we run out of time, because it is bound to be even more interesting and intriguing than this body that you just left behind. For one thing, it's a heck of a lot bigger. It is.

Ceres is the largest body between the Sun and Neptune that has not yet been visited by a spacecraft. Now, when I say that, some of the moons of the outer planets are very large, but of course, Cassini, Voyager, Pioneer flew by the outer planets and glimpsed some of these moons, albeit from a distance, but still the general vicinity. But no spacecraft has ever come near Ceres. It's a very large body. It's more than 600 miles in diameter. It may have subsurface water, perhaps even liquid water. I think there are going to be a lot of interesting things to see on this dwarf planet. And when do you arrive?

The spacecraft will get there in 2015 and go into orbit and then undertake a detailed exploration just as it did at Vesta. And how long will Dawn be active at Ceres? And then is that the end? I mean, is there any expectation that you might then be able to escape the influence of Ceres? This has got to be something that has been considered. Having just left Vesta with the outstanding success of our exploration there, we're using that experience to do the design for our exploration of Ceres. And so I don't know yet exactly how long it will take. It certainly will be more than six

months in order to get all of the measurements that we want to get. And as for what we'll do after that, there are many possibilities. Now, of course, first, it will depend on whether the spacecraft remains healthy and whether NASA chooses to invest more resources in it. Money, basically. That's right. NASA has limited resources, and it's a big universe. There are many, many wonderful missions to undertake, that is, missions that are already in flight that will have many exciting objectives and new missions that we want to get going. flight that will have many exciting objectives and new missions that we want to get going.

And after all, by that time, your spacecraft will have unveiled two worlds that have never been visited before, and that will be quite a legacy. I think it is. I mean, to me, these are among the last uncharted worlds in the inner solar system. So I think two worlds for one mission, it's a pretty good deal. Thanks very much for hosting us and showing us around your beautiful home, and also for continuing to be one of those who's shepherding this wonderful interplanetary mission, really the first of its kind, hopefully to be followed by many others. You're welcome. I appreciate your interest. Now, I only have one other question. Do I get to meet Event Horizon?

You can. He's in the next room. That's your iguana. It is, right. Thanks so much, Mark. Mark Raymond is the Dawn mission's chief engineer and the director of that mission. He has a slew of awards that I just saw some of, at least on the wall in his space room, upstairs in his home. We'll be right back with our in-house planetary scientist, Bruce Betts, for this week's edition of What's Up in just a moment. It's on for What's Up with Dr. Bruce Betts, the Director of Projects for the Planetary Society.

This week, we come to you from the science guy's office, the boss's office. He's got such cool stuff. And he's not here. He's not here. And we are. Look at this. Look at this. Really cool.

This is that British Skylon prototype spaceship. This is so cool. Look at that. It that it's so mean it's just crazy that's actually switching it around the room god it's cool hey what is that that that's where my phobos bio module oh yeah look at that yeah i lent him one for a conference and i never did see that again there it is right there let's go through his drawer it's just extra engineering hardware one-on-one for a conference and I never did see that again. There it is right there. Let's go through his drawers. It's just extra engineering hardware. But yeah, balsawood planes, there's just all sorts of cool stuff. It's the kind of stuff you'd expect to find in the science guy's office. Yeah, it pretty much is. Tell us what we might

find in the night sky. Well, in the evening sky, Jupiter, the dominant thing over there in the east in the early mid evening. And if you look on November 28th, it'll make a lovely sight with the moon very close to it. But the pre-dawn is where there's quite the party going on. You've got super bright Venus dominating the pre-dawn east, but Saturn is rising up and getting closer and closer as the days go along to Venus. Saturn being much dimmer, they're only one degree apart on November 27th. And special guest appearance by Mercury low in the pre-dawn east, so below those other two in late November and early December. Late November and early December.

All right, we move on to this week in space history. It was this week in 1969 that Apollo 12 became the second set of people hanging out on the surface of the moon. Really not that long after Apollo 11. They were cranking them out for a while there. Yes, they were. Speaking of which, no, speaking of nothing, we move on to the Rundrum Space Fact. Yeah. There's a nice kind of natural echo in there. The acoustics are pretty terrible, actually.

Okay, can we move on now? Oh, sorry. So I find this interesting, which is why i share so the sun of course the very center of the sun has the nuclear fusion this ridiculous density 151 times the density of water but if you average the entire volume of the sun the density is only 1.4 grams per cubic centimeter water is one so it's not that much more dense on average than water and earth really kicks its booty because we have an average density of 5.5 compared to that wussy sun fascinating watch i'm gonna get a sunburn in the middle of winter soon just to make up for that i know a few people who are

almost as dense as the core of the sun why are are you looking at me like that? Because it's time for the contest. No, nothing to do with density. Right. I asked you, what was the last space mission that launched exactly two people? No more, no less. How did we do, Matt? Real well. And the prize this time around, we've gone back to a Planet Show Radio t-shirt.

We're going to get new shirts soon. We know. You've all got one now. Everybody's won. Actually, there are a lot of people who have never won a shirt. Exactly. And we're going to give away a year of year in space wall calendars for a while. In fact, next week we'll start that.

You're waiting for me to say the winner. Desperately. It was Ian Bethune. Ian Bethune of Edinburgh, Scotland. Edinburgh? Yeah. He works at the University of Edinburgh. Oh, that'd be great.

He is at the Supercomputer Center there at the university. He's a project manager. So congratulations, Ian. He said it was the Shenzhou 6 mission in 2005. Yeah, it just wasn't true. I'd throw people off looking farther back or looking at other countries. But yeah. So is this cool or what?

We got a guy in Scotland who won the contest with an answer about two Chinese taikonauts on this American radio show that's disappointed people around the world who did not win. Till you reached that last part. It was really cool. Oh, okay. No, that's good. That's good. All right. We move on. Wait, wait. Before you go on. was really cool. Oh, okay. No, that's good. That's good. All right, we move on to the next. Oh, wait, wait.

Before you go on. No, we don't move on. No, we don't. Mark Wilson of San Diego, California. Mark said he originally thought that it was Han Solo and Chewbacca when they took off in the Millennium Falcon to help Luke destroy the Death Star. But after all, that mission was a long time ago in a galaxy far, far away. Yeah, and it's the long time ago that, of course,

discounts it for this contest. And also, I can't remember if I said people. I don't know if Wookiees... We don't serve his kind in here. I mean, if Chewbacca wants to be counted, that's fine with me. That was a terrible wookiee sound wasn't it that was really bad that was chewbacca with the flu and a gag in his mouth i've never attempted wookiee before and i never will i'm not going

to try i i don't i don't speak wookiee okay but i do speak trivia contest and we move back to to our friend the sun what is the third most common element in the photosphere of the sun by weight in case there's any questions so most people would come up with hydrogen helium top two but when you go way down the list what's number three go to planetary.org slash radio, find out how to enter. I like this. Good question. So this week, the deadline is November 26, Monday the 26th at 2 p.m. Are you sure that's right?

Pacific time. I am absolutely confident. Excellent. And what are we giving away? Another one of those fabulous calendars? Yeah. Let's do that. Urine space wall calendar.

They really are beautiful. They are awesome. All right, everybody. Go out there, look up at the night sky and think about what toys Bill Nye has in his office. Thank you. Good night. Alright, I'm throwing the ball so lighter now.

Whoop. Oh. He's Bruce Betts, the Director of Projects for the Planetary Society. Joins us every week here for What's Up. I hope you can buy another one of those. Planetary Radio is produced by the Planetary Society in Pasadena, California

and made possible by a grant from the Kenneth T. and Eileen L. Norris Foundation and by those intrepid explorers known as the members of the Planetary Society. Clear skies. Thank you.