Planetary Radio: Space Exploration, Astronomy and Science - Big News All Around the Solar System From Emily Lakdawalla

Episode Date: March 26, 2012

The 2012 Lunar and Planetary Science Conference attracted many of the world's finest planetary scientists. This year it also attracted Emily Lakdawalla and Bill Nye the Planetary Guy. Emily provides a special report on amazing new discoveries about our solar system. Learn more about your ad choices. Visit megaphone.fm/adchoicesSee omnystudio.com/listener for privacy information.See omnystudio.com/listener for privacy information.

Big news from all around the solar system, 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. Just our regulars this week, two of them, Bill Nye and Emily Lakdawalla, have just returned from the 2012 Lunar and Planetary Science Conference in the Woodlands, Texas. Emily will give us a special report on some of the exciting science unveiled there. I think you'll agree that it makes our planetary neighborhood even more astounding. Later, we'll visit with Bruce Betts for What's Up.

First, though, the science and planetary guy. Bill, I want to welcome you back to Planetary Radio, but also back from LPSC, which we'll be talking to Emily about as well, reversing the order here a bit. Tell me about your experience at the Lunar and Planetary Science Conference. Well, it's just a party of geologists who study other worlds. They do have a good time, don't they? Well, it's good. No, it's great. And they're not just geologists, but a lot of people who you would call an astrobiologist, many, many

of those, talking about the big questions. What happened on Venus? How did it end up the way it is? questions. What happened on Venus? How did it end up the way it is? What's going on on Mercury? They really are engaged in trying to understand what I like to express as our place in space. But we also had a couple of presentations. We had a forum where people talked about political strategies to deal with this very, let's call them stressful budget cuts. And there were presentations by John Grunsfeld and Jim Green from NASA, NASA's Planetary Sciences, or Science Directorate, and especially the Planetary Sciences, talking about what we're going to do when you're missing $309 million every year for the next five or six years. And people agreed after a little bit that we can't go shooting each other. This

is to say, you can't go taking money from James Webb Space Telescope to pay for this $309 million cut to planetary science. You can't cut commercial crew investments because they're the future. They're certainly the medium-term future, let alone the short-term future. And people went around and around about this. It's such a small amount of the United States budget, $309 million. But it's enough to make it impossible to fly any more big missions, like the Curiosity rover, which lands in August. And people are justifying or pointing out or discussing the great value one day of the space launch system, should it ever

come into existence. This would be a rocket in 2017. And then again, in 2021, with four years between launches, it probably will get canceled. I mean, politically, the future Congresses will probably cancel it. That aside, we're all sticking together. And I'm very excited about what might be a minor news item that is closely related to all this. SpaceX and the United Launch Alliance, these are two big rocket companies, are looking to use the old space shuttle launch pad. And I presume the vertical assembly building, the VAB. And this would be quite a boon, Matt. This would be using old infrastructure, modifying it a little bit, and putting it in spectacular service for, if I may, the betterment of humankind. It really would be a great thing to repurpose these old weldments,

these enormous buildings and gantry towers and stuff that were designed for this special purpose and adapt them to be a little more versatile. It's cool. It's a great idea. And you know what? It strikes me that this isn't the first time this will have happened because that stuff was built for the Apollo program. You have crystallized my thoughts. There you go. And when you go to the vertical assembly building, you see where they cut a big hole in the side to get the vertical tail of the – they had to wheel or crane the space shuttle into that building at an angle so it would fit.

It's quite a crazy thing. For any listeners, if you've never been to the Vertical Assembly Building, it's really an astonishing thing. an astonishing thing. It goes straight up, taller than or almost as tall as the Washington Monument in standard units or English units, 500 feet straight up. It is magnificent. Hollow. It's really something. And so it'd be great to use that, the modern word is infrastructure, to launch the rockets of the future and take people to the international space. By the way, they had a great success with a robotic mission to the space station. It got up there and transferred some material without having to use people spacewalking. And so it saves a lot of money and time. It's really good.

So there are good things going on. And I'm going to look for that story online so that we can put up a link at planetary.org slash radio for the listeners. Bill, I've got to let you go. I think you're going to a wedding. No, I came from a wedding, but I'm going to the National Science Teachers Association convention in Indianapolis. These are my people. The science teachers and the science guy go way back. So many students now watch the show, the old science guy show, on recording.

They don't watch them on television when they come home from school in the afternoon. So I still have this crazy, huge following among science teachers. It's really fun. It's very gratifying. Well, I got to fly, Matt. Bill Nye the Planetary Guy. He is the chief executive officer of the Planetary Society. He joins us here every week for What's Up?

Have fun with those science teachers. And I will be back in a minute for more about the LPSC with Emily Lakdawalla. Emily Lakdawalla may never feel quite so professionally at home as she does at the Lunar and Planetary Science Conference, or LPSC. Surrounded by thousands of like-minded planetary geologists and other scientists, the Planetary Society's Science and Technology Coordinator spent last week jumping from poster session to presentation to luncheon, jumping from poster session to presentation to luncheon,

gathering the very latest news and findings by the top experts on worlds throughout our solar system. She had only just returned to Southern California when I reached her via Skype. Emily, welcome home, first of all. Thank you very much, Matt. It was quite a busy week. Yeah, you must have very sore thumbs, because, boy, were you hitting Twitter. And it was very hard to hit Twitter, actually, because we had terrible network coverage in there. But I took, I think, probably 20,000 words worth of notes. So I don't know what I'm going to do with it all, but I'll try to get through some of it today. Well, some of this has made it to the blog. A lot has not. And we're

going to do a little review here, a little extended conversation with Emily. And I keep saying Emily, but maybe I should say MLA. M-L-A. Right. Because that caused some confusion, didn't it? Yes, MLA certainly caused a lot of confusion. MLA is one of many TLAs, which is short for three-letter acronyms that I heard this week. And MLA is the Mercury Laser Altimeter on Messenger. And they have an absolutely gorgeous map right now. And it's showing them a lot of very interesting things about Mercury's topography. One of the most

interesting is that if you look at this gigantic basin that Mercury has called Caloris, it's one of the biggest impact basins in the solar system. Most basins have a raised ring or even multiple rings, and that shows up in topography. But if you look at Caloris' topography, there's virtually no sign of rings. And even stranger than that is that there's some places of the floor of the basin that are actually higher than parts of the rim. And so Caloris, the topography has been totally wiped out and replaced by these more linear kind of very long wavelength folds in the crust of Mercury. And this is the kind of thing that they expect to happen because Mercury has shrunk with time as its core is solidified.

But I don't think they expected Caloris' topography to be so subtle. In fact, they've mapped ridges all over the planet, and some of them are lining up into these fold and thrust belts, which really you've only seen on Earth before. So that was a very exciting part of the MESSENGER mission. So MESSENGER is indeed living up to what we had hoped, that it's revealing a lot of surprises on this planet. Absolutely. And of course, the more that we learn about Mercury, the more that we find that it's a

unique planet. It's not the Moon. It's not Mars. It's not Earth. It's had a totally unique history. And it's possible that it has an internal structure that's also quite different from other planets. We know that it has a liquid outer core because it has a magnetic field. But actually, that could be a liquid middle core.

There could be a little layer of core material made of iron sulfide, which we would know as iron pyrite, that's plastered on the bottom of the mantle at the very top of Mercury. And so that makes Mercury's uppermost stiff layer very, very dense. And that's unusual compared to all the other planets. However, there are some other geophysicists that I talked to during the conference who weren't totally convinced by the MESSENGER team's arguments here. Another thing that is extremely gratifying to me and many other people is seeing the amount of mass media, non-science media attention that Mercury is getting out of these reports at LPSC. I don't think you had seen that it was, and I think it was from the laser

altimeter, it adorned the above-the-fold front page of the LA Times just a few days ago. Yeah, and there were quite a few reporters there on site, and they had, for the first time, some press conferences out of the meeting. So this is definitely a very exciting time in planetary science, and it was very exciting to be there. And I just want to mention in passing that you do have a major blog entry from the week of LPSC about this possible, possible find of ice up near the poles, much as we've now found ice, we believe, at the poles of our own moon. Yeah, and I'd say that scientists are pretty confident about this one, actually. They've thought that there was ice at Mercury's poles ever since, I think, 1991,

when the Arecibo radar turned to Mercury's poles and found this very reflective material up there within in very circular patches that look a lot like craters. And so Messenger has actually really, I think, confirmed this finding from Arecibo's radar, where they did find that there was quite a bit of hydrogen near Mercury's poles. They find that the material is not very reflective to the laser altimeter. But that's because of an even more exciting result, which is that the same process that traps ice in the poles has also been trapping complex organics, the kind of stuff that comes in from carbonaceous chondrite

meteorites. So at Mercury's poles, you've got ice, you've got organic material, and if you dig just a bit down below the surface, you actually have a pretty comfortable temperature. So, hey, let's settle Mercury. Life on Mercury, maybe actually a livable place. It is an amazing place, our solar system. Another amazing place, which you do talk about in a blog entry, but have more to say, is Titan, that cloudy moon of Saturn. Yeah, I wrote quite a bit about Titan's changing seasons. Cassini has been there long enough to see it arrived at near southern summer solstice and it went through the equinox.

And now we're seeing the seasons change toward the northern summer solstice. So Cassini is seeing a lot of weather changes, some major storms of methane that have changed the appearance of the surface. But I'm actually going to talk about something else today. And that's some gravity results. Now, gravity is kind of an esoteric subject. Basically, they track a spacecraft as it flies past a planet. And just from the little motions, little accelerations, they can tell actually quite a lot about the interior structure of a moon. This is the Doppler effect because of the radio transmissions, right?

That's right. And the way that the Doppler effect affects the spacecraft depends on how much the mass is concentrated near the center of the moon. Because Titan has an elliptical orbit, this actually changes over time because of the way Saturn's tides affect Titan. So what Cassini has found, actually, is that Titan, it's confirmed that Titan has an internal ocean. It must be at least partially differentiated and it must currently have a fluid layer which really can only be liquid water underneath the surface. And that's really quite an amazing thing for Cassini to have confirmed this without even being an orbital mission. We're going to have to do this at Europa with an orbiter eventually. But it looks like, based on what Cassini has accomplished, that we might be able to do the same thing at Europa with just a Jupiter orbiter and not a Europa orbiter. Although, of course, a Europa orbiter would get better quality data. So that was really, I think, quite an accomplishment of the Cassini team.

But this is flabbergasting. Methane seas above and water ocean below? Good Lord. Plane seas above and water ocean below? Good Lord. Yeah, it's worthy of being called a planet. And actually, I was keeping track this week of how many things that are technically not planets that were called planets during the week. Because, of course, you know, we're all geologists. We're discussing these planetary processes, things like rain and tectonics and volcanism and all that kind of stuff. And it's things that happen on planets. And it makes it extremely hard not to call even pretty small things like Vesta a planet. That's Emily Lakdawalla sharing her notes about the just-completed Lunar and Planetary Science Conference.

She'll tell us more in a minute. 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.

We're going to continue our extended visit with the Planetary Society's ace blogger, Emily Lakdawalla. She's back from the 2012 Lunar and Planetary Science Conference, bursting with the coolest of data revealed there about nearly every spot in our solar system. She had just mentioned Vesta, second largest of the asteroids, before the break. You heard some results from the Dawn mission, which of course is orbiting that little minor planet right now. That's right. And these results are a lot more preliminary

than the messenger results are because after all, they haven't been at Vesta very long. But they're beginning to look at the patterns of different kinds of materials that are on the surface. And they see these kinds of wispy tracks of bright materials in some places and dark materials in other places. And they're beginning to see little traces of impact melt

running inside some of the craters. They've looked at a lot of the craters and found that they have very weird shapes. And it's because Vesta has really extreme slopes. Most places in the solar system have, you know, slopes of maybe up to, I don't know, 15, 20 degrees would be pretty steep. On Vesta, you have some slopes as steep as 40 degrees. And that's just nutty. And it makes the craters very strange shapes. And another thing, speaking of hydrogen on planets and water on planets, Vesta could, in theory, have water ice at its poles like other places do. It looks like Vesta does not have any water ice at its poles, but it actually has a reasonable amount, about 400 parts per million of hydrogen concentrated more toward its equator in the ejecta from the

gigantic impact that made its huge southern crater. So it does have some water. These are probably more different kinds of minerals that you ordinarily get on asteroids. And it's not in the form, it's not like ice. You couldn't go up there and melt it and drink it. But it's got a significant amount of hydrogen. That's pretty cool. Let's go a bit closer to the sun. You got an update from Steve Squires about, well, I can't say the Mars exploration rovers anymore, but about what opportunity is up to.

Yeah, you know, I'm going to have a hard time because I keep calling them the Rovers. And now there's only one rover, and then there's another one that is not one of the rovers that is on its way to Mars. So I'm really tongue-tied. So, yeah, Steve Squires, every LPSC, he gives a very well-attended, very rapid talk about the latest thing that Opportunity has been doing in the last year. And this last year, of course, the story was that it arrived at Cape York, which is part of the rim of this gigantic crater, Endeavour Crater. And he looked at the rocks with all of the different instruments on Opportunity and has confirmed that they're a kind of rock called Swaybite.. Now, suavite is a rock that forms particularly at the sites of impacts. And now, of course, we knew that it never was an impact.

But still, it's really nice when things match your expectations. And it's a rock that's a breccia. It's a kind of rock that has lots of chunks of other rock cemented together by a much finer matrix of material. And in this case, it's probably impact glass because its crystals are so tiny that Opportunity's microscopic imager can't even see the grains in the matrix of this rock. Did Steve also say anything about the health of Opportunity

as it heads into the winter? Opportunity's really doing okay right now, and we're actually coming out of the winter. Now, Opportunity has finished the winter with pretty dusty solar panels, and I actually did hear some hallway conversation from people who are concerned, not about this winter, but next winter, unless Opportunity gets a real good cleaning event. There is some concern about her health.

But what they are going to be able to do this year is start driving south. They're going to leave Cape York and will maybe actually start climbing mountains, which is just incredible because Spirit used to do that, but Opportunity has never been on anything you could even remotely call a mountain before. And who knows, if she's lucky, she'll get a nice gust of wind that'll clean those solar panels off again and give her a new lease on life. Very briefly, because you do cover it in a fairly extensive blog entry from last week, just summarize what we've learned about Phobos and Deimos up above Opportunity. This was a talk I was really looking forward to because it

was given by Abigail Freeman, who is one of the kids who was on the student astronaut program on the Mars Exploration Rovers that the Planetary Society ran, and I trained these kids. Of course, she's not a kid anymore. She's an advanced grad student with Ray Arvidson at Washington University. She was using omega and chrism data. And these are the two imaging spectrometers on the Mars Express and Mars Reconnaissance Orbiter spacecraft to study the composition of Phobos and Deimos. And she found that the two have surfaces, reddish surfaces that are very similar, and actually similar to each other, but dissimilar to anything else in the solar system. But then there was this other talk that was given by a guy who was not a geologist.

He was an engineer. And the reason that there is an engineer giving a talk at a geology conference is because there is this theory that I've always really liked that explains the grooves on Phobos. And Phobos is covered with these parallel linear grooves. Some of them seem like chains of craters and some of them don't. And there's this idea that said that maybe they were just chains of secondaries from impacts on Mars where a gigantic thing hit Mars. And then it sprays up this liquid impact melt that separates into little blobs and kind of goes all along Phobos and makes

these grooves. And he had come up with a lot of very convincing reasons why this was a feasible idea. Well, this engineer came to the meeting and he knows orbital mechanics very well. And he went through six different arguments about why this is, from an orbital mechanics point of view, pretty ridiculous, unfortunately. So I think that was the death of a very pretty theory. Too bad, I guess. But listen, the truth is the best outcome of all. Just a few seconds left to bring it very close to home. And tell us what's happening early in the science mission of GRAIL, those twin spacecraft circling our own moon. So GRAIL has

only just started its science mission. It's only a couple of weeks into the mission. So there was only one GRAIL talk given by the principal investigator, Maria Zuber. And I have to say, it was a very happy Maria Zuber who was up there talking about the health of her spacecraft there in orbit around the moon. And with just 15 days worth of data, she showed how it's already improved on what we know about the lunar gravity field. And that's even just on the near side, which we've mapped fairly well. The far side has really not been mapped all that well. And so she was very pleased with the quality of the data,

and she also was very happy to announce that NASA has actually funded their extended mission. So they're going to go for twice as long as they expected to. Excellent. Emily, I'm tired just hearing you recount all of this. Get some rest and recover from LPSC. And we'll look forward to talking to you again very soon. Yeah, it was exhausting, but it was many people said it was one of the best LPSCs in many years. So I was very pleased to have been able to go. A bit of a party too, wasn't it? It always is. Emily Lactewal is the science and technology coordinator for the Planetary Society and a contributing editor to Sky and Telescope magazine. And we will be back with her with her regular commentary on next week's Planetary Radio.

I will be back with Bruce Betts for a look around the solar system in this week's edition of What's Up. Wow, it's kind of weird. It's almost the exception now to connect with Bruce via Skype rather than talking to him at headquarters. But Skype it is this week. Are you there? Testing one. Hello, hello, hello, hello. It's a miracle. It's a miracle. Welcome. Tell us about the night sky. Goodness. We've got Venus and Jupiter over in the west after sunset, still super bright. Venus staying high, Jupiter dropping lower, Venus the brighter of the two. Look over in the opposite side of the sky over in the east, and you will see Mars looking orange-ish and dimming as the weeks go along as Earth and Mars grow farther apart. And Saturn also rising in the early to mid-evening now over in the east, looking yellowish, cool with a telescope.

We move on to this week in space history. And this week was a big week for Heinrich. on to this week in space history. And this week was a big week for Heinrich. That's right, Heinrich Olbers discovered it's the 210th anniversary of Heinrich Olbers' discovery of Asteroid 2 Pallas, Asteroid Pallas. And then five years later, during the same week, he discovered Vesta, which of course Don is at right now, orbiting and playing and learning all sorts of good stuff.

Besides Ceres, the two largest asteroids out there, both discovered by Heinrich this week, 210 and 205 years ago. I forgot that Pallas is number three behind Vesta. It is. It is, but they're confusing in that they're very similar. Depends on whether you're talking mass and volume, but yeah, basically. Cluster of Pallas and Vesta pretty close together, and Ceres way out ahead,

and everyone else behind Pallas and Vesta. Well, happy anniversary, double anniversary, Heinrich. Okay, I'm sure he'll appreciate that. All right, we move on to... Run, run, run, run. Run, run, run, run, run. Run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, run, for everyone. If you, as I know, you have a summer home, I believe, in the cloud tops of Jupiter. When you're there. We don't get there often, but yeah.

When you're there and you look up in the sky, I know it must be stunning to see Io looking just slightly larger than the full moon in Earth's sky. Although much less bright because of it being much farther from the sun. All right, let's go on to the trivia contest. And we asked you, what is the name, unofficial name, for where Opportunity is now? And we'll spend the Martian winter. How'd we do, Matt? This is so interesting. This may have stumped a lot of people because we didn't get that many entries this week.

Interesting. This may have stumped a lot of people because we didn't get that many entries this week. Random.org picked out first David Bixler, who would be a first-time winner if this is correct. He is out of Seneca, Missouri. Now, it's not the answer we were looking for, but technically it may be correct. He says that Opportunity is currently parked for the Martian winter next to a rock named Amboy on Shoemaker Ridge, the highest spine of the Cape York segment of Endeavor Crater's rim. Is he correct? my mind was Greeley Haven, which defines the more localized area that it is in and will spend the Martian winter. But as I understand it, Greeley Haven is part of Shoemaker Ridge that's part of Cape York, so it's all one big party. Greeley Haven, named after Ron Greeley, Arizona State professor who passed away in the last

few months and was a trainer of planetary scientists and involved in a lot of the political and scientific committee side of things and also a great guy. Ironically, I think I hinted at a passed away planetary scientist. Well, Shoemaker Ridge was named after Gene Shoemaker, although he passed away in 1997 and studied impacts particularly, made a lot of impact there, so to speak. So I'd say we go with it. Yes, it wasn't quite what I was after, but it is, I believe, technically accurate or darn close. I'm going with yes. So congratulations to you, David.

You squeaked through here. We're going to let it slide because you are correct. And we're going to send you a Planetary Radio t-shirt. We also got from Tony Gray this beautiful image. It's the Vista from Greeley Haven. So I think this is the next place I'm going to build a guest home. Hey, nice. You'll be able to check out more moons.

That's right. Yeah. Two is better than one. Speaking of moons, going to a place that we've discovered. Back to the place we've discovered 66 so far. And, oh, wait. No, okay, I thought that was another one coming in. And that's Jupiter.

Here's your question. What is the fifth most massive moon of Jupiter? So we have the four really big ones, the Galilean satellites, Io, Europa, Ganymede, and Callisto. And then, as they said in the Gill, Ganymede, and Callisto. And then, as they said in the Gilligan's Island original theme, and the rest. Well, this is the most massive of the rest. And note, kind of like that Vesta Pallas thing, in terms of size, it's really close. In terms of what's five and what's six, in terms of mass, it's not. So I'm asking you, what's the fifth most massive moon of Jupiter? Go to planetary.org slash radio. Find out how to enter. You have until Monday, April 2nd at 2 p.m.

Pacific Daylight Time to get us that answer. And that completes another one. All righty, everybody, go out there, look up the night sky. Think about what moon you'd like to be seeing up in that sky. out there, look up at the night sky, think about what moon you'd like to be seeing up in that sky. Thank you and good night. La Luna! La Luna! I don't know, there'll be a few people out there who get that reference right, that cinema reference. He's Bruce Betts, the Director of Projects

for the Planetary Society, who joins us each and every week here for What's Up. Join us next week for a visit with world-famous searcher for extraterrestrial intelligence, Jill Tarter. Planetary Radio is produced by the Planetary Society in Pasadena, California,

and made possible by the Kenneth T. and Eileen L. Norris Foundation and by the members of the Planetary Society. Clear skies. Thank you.