Planetary Radio: Space Exploration, Astronomy and Science - Opportunity, Phone Home!

Episode Date: September 12, 2018

The dust is settling on the Red Planet.  Is the remaining Mars Exploration Rover about to rise and shine after three months of slumber?  MER Project Manager John Callas returns with a realistic yet hopeful assessment.  He also tells us what Opportunity will be asked to do after we hear from her.  Planetary Society Senior Editor Emily Lakdawalla returns with a preview of China’s next two missions to the Moon, one of which will make the first-ever farside landing. How close is the nearest black hole?  We’ll get the answer as Bruce and Mat explore the night sky in this week’s What’s Up.  Learn and hear more at: http://www.planetary.org/multimedia/planetary-radio/show/2018/0912-2018-john-callas-opportunity.html Learn more about your ad choices. Visit megaphone.fm/adchoicesSee omnystudio.com/listener for privacy information.See omnystudio.com/listener for privacy information.

Opportunity, please phone home this week on Planetary Radio. Welcome, I'm Matt Kaplan of the Planetary Society, with more of the human adventure across our solar system and beyond. The skies over the Red Planet are clearing, and the Mars Exploration Rover team is anxiously, but hopefully, waiting. And the Mars Exploration Rover team is anxiously, but hopefully, waiting. We'll talk with MER Project Manager John Callis about the outlook for the little rover that has already spent nearly 15 years on Mars. How close is the nearest black hole? The answer will come during our What's Up segment, and it will win someone this week's space trivia contest. China is preparing its next voyages to Earth's moon.

We go to the Planetary Society's senior editor, Emily Lakdawalla, to learn more. Emily, other than talking about these terrific missions that are going to get underway very soon, this is also a sneaky way for me to congratulate you on your very first edition of the Planetary Report, the magazine that goes out quarterly to all Planetary Society members, and the first one that you've been in charge of. That's right. It's my first magazine. I got it out on time. It has two feature articles from wonderful contributors. I've got ESA's Elsa Montagnon talking about BepiColombo, the upcoming JAXA-ESA mission to Mercury. And I've got Lang Xiao talking about the upcoming Chinese landers to the moon, the Chang'e program. Elsa Montagnon, a program note, will be our guest here on the program, talking about some of what she covers in greater depth in that article in what we call TPR, the Planetary Report. But we're not likely to talk to that author of the article

about Chang'e 4 and 5. Correct me if I pronounce that incorrectly yet again. So what is China about to begin? Well, China is actually continuing a long-running lander program on the moon. So up there right now is Chang'e 3. It's a lander that landed with a rover. The rover unfortunately malfunctioned, but the lander has been operating for years doing ultraviolet astronomy on the surface. Later this year, they're going to be launching Chang'e 4, which is built off the backup spacecraft, the engineering backup for Chang'e 3. So it's obviously a very similar mission, but they're sending it to a very different

place. They're sending it to the lunar far side. It'll be the first ever landing on the far side of the moon. They already have in orbit a relay satellite named Chitiao that will be relaying the radio communications from the backside of the moon up to the relay satellite and down to Earth so that we can talk to the spacecraft. After that mission, later next year, they'll be launching Chang'e 5, which is a robotic sample return mission that will be the first return samples from the moon since the Apollo and Luna days ended. And so that's going to be very exciting. They're going to be sampling some very young basalts on

the moon. Now, young is relative. It's still 2 billion years old, but there's still going to be some of the youngest rocks we've ever returned from the lunar surface. So I'm really looking forward to that one. And you have an illustration as part of that article, which shows what to me looks like almost a forest of landings that have taken place on the side of the moon that we can see. But just this one that hasn't even happened yet on the far side. Yes. There are a lot of limitations on where people can land on the moon. But the biggest one is the fact that the moon faces Earth with the same face all the time. And so communications are hard if you want to go to the other side of the moon. So that's why this will be the first one. You know, the Indians are also planning to do a lunar lander mission, and they're going to another relatively unexplored place, the south pole of the moon. They're looking to launch early next year. And that mission, Chandrayaan-2, I think it's called, you also have a short piece about

in this brand new edition of the Planetary Report. Emily, is there anything else that you want to mention that's showing up in this first TPR that you've edited? Well, I had fun picking out what my column was going to be. And my recurring column will be one called Where We Are that shows you a map of the solar system and where every single spacecraft beyond Earth orbit is traveling right now. And there are 30 of them on this map this time. That's a lot of interplanetary spacecraft.

Definitely something to celebrate. And it is a great addition to the magazine. Thanks very much, Emily. Thank you, Matt. That's Emily Lakdawalla, Senior Editor for the Planetary Society and our Planetary Evangelist, and now the Editor-in-Chief of the Planetary Report.

John Callis has been the Mars Exploration Rover project manager for 12 and a half years, but it was in 2000 that he joined the project that would send two small but mighty rovers to the Red Planet. That was three years before Spirit and Opportunity would begin their voyage. We lost Spirit in 2010, but not before it had spent six years following the water and accomplishing other great science as our emissary on the red planet. Spirit's sister Opportunity soldiered on and on until last June, the solar-powered robot was halted by Mars itself. Now, hopes are rising that the little rover will soon reawaken and reestablish contact. And here's an update from John that he gave me hours before we published this episode.

The MER team delayed beginning the period of what they call active commanding till at least late in the day on Tuesday, September 11th. You'll understand what that means as you listen to this conversation I had with John the day before. what that means as you listen to this conversation I had with John the day before. He spoke to me from his office at the Jet Propulsion Lab near Pasadena, California. John, thank you so much for returning to Planetary Radio. It is a great pleasure to talk to you as a leader of the Mars Exploration Rover's mission. How are we doing 14 and two-thirds years into this 90-day mission? Well, we have a situation on Mars. As of June 10th, we have not heard from the rover Opportunity. A large global dust storm has obscured the sunlight over the rover site, shutting down the rover's ability to generate

electricity, which powers the vehicle. And since June 10th, we haven't had any signals from the vehicle. Our expectation is that the rover will survive the storm when the sky is clear, and they're clearing now. And we've been listening, and our hope is that opportunity will fall on home soon. I read about a lot of optimism on your part by other people on the team, and it sounds like you're sticking with that. Well, our estimates are that the vehicle should stay warm enough during this storm. People should appreciate the rover actually powers down every single day. So the fact that we're powered down right now is no different than what it normally goes through every day. It's just that it's for an extended period of time. And so as long as it stays warm enough, the vehicle

should power back up when the sky's clear and as long as there's not too much dust on the arrays. Are we fortunate that it's, I think it's summer on Mars, or at least where opportunity is? Yeah, we are fortunate that we're at the time of maximum solar energy availability on Mars and the warmest temperatures. And both of those are contributing to our optimism about hearing from the vehicle again. I have read a lot about this term called tau, which is this measure of how much light is able to get to Opportunity or anyplace else on the Martian surface. Can you give a brief explanation of what we're talking about here? Yeah, this number tau, it's the Greek symbol for T. We use it as a measure of what's called

atmospheric opacity. And people will be familiar with this because, you know, at the sunset as you're driving along and the sun is on the horizon, the sun looks very orange because you're looking through a lot of atmosphere. And on dusty days or smoggy days, the sun is even dimmer. On Mars, we do the same thing. We use our cameras and we take a picture of the sun and we know how much light is coming from the sun. So how much it actually gets through the cameras tells us how much is absorbed in the atmosphere. On Mars, because it's a dusty planet, there's actually a tremendous amount of dust that obscures sunlight and affects the amount of energy production on the rover. So

we like to track this quantity continuously throughout the mission. Normally on Mars, this Tau number is less than one. In good weather, it's about 0.5. At the peak of this recent storm, At the peak of this recent storm, we measured a historic high of almost 11 in tau. And to make the point with people, actually, it's an exponential coefficient. So it's like the earthquake magnitudes. Yeah, yeah. So each unit of tau is a factor of 2.7 worse than the previous number. To go from a tau of, say, 1 to 2 is actually a factor of 2.7 worse than the previous number. To go from a tau of, say, 1 to 2 is actually a factor of 2.7. A tau of 11 is almost completely dark sky. I mean, it was nighttime during the day

for the rover at that time. Man, as if you were under a solar eclipse, but for months at a time. Yes. That's amazing. Now, how are you able to determine the tau? You obviously can't do it from opportunities observations. We've been relying on orbiting spacecraft, mostly the MARSI, the Mars Color Imager Instrument on the Mars Reconnaissance Orbiter. And they can look down at the surface. They take daily images of the planet. And by using a combination of identifying features on the surface and some algorithms, they can make an estimate of tau over the rover site. And we've been using that as a proxy for the conditions for Opportunity. And

that proxy has been showing that the storm is clearing, and it's clearing now. And so we're hopeful soon to be able to hear from the rover. Kudos to Bruce Cantor and all the folks at Malin Space Science Systems for all their help with that. Has there been any help getting data from Curiosity, which is pretty far away on the red planet? It's helpful in a general sense. Gale Crater is very different from Meridiani. However, this is a global storm. And so there are global aspects of the storm that Curiosity can measure for us that we can use to as an indicator of what's happening. So the storm is clearing all over the planet. So improvements in Gale Crater suggest improvements at Meridiani for opportunity.

I don't know if you've had a chance to see it yet, but my colleague AJS Rail has posted the latest of her Mars Exploration Rover updates at planetary.org. She did so as we speak just yesterday, September 9th, Sunday, September 9th. It is, as always, with the stuff that comes from her, it is very comprehensive. She talks about, as we have elsewhere on the Society website and around the world, frankly, about a plan, this plan that you led the formulation of, I believe, for how the recovery operation, the attempt to reestablish contact with Opportunity, will be undertaken. Can you talk a little bit about that? Describe what's ahead.

Right. First of all, this recovery is very different from what we attempted with Spirit. The big differences are that Spirit was going into winter, so there was no expectation or little expectation we'd hear from the vehicle until we got on the other side of winter. So that was a long waiting period there. And the other thing is that Spirit's fault protection had a misset parameter that prevented it from phoning home autonomously. So we had to actively command in the hope of trying to recover Spirit, and we never did. In the case of Opportunity, the vehicle, when it powers up, will automatically phone home. And so for us, it's a listening

campaign. And we plan to listen. We have been listening since the loss of signal back in June. And we plan to listen through at least January, which would be through the period of dust cleaning events, seasonal dust cleaning events on Mars. So it's a matter of waiting. However, we have identified the potential for a couple of complicating fault modes with the vehicle where an active command might help to resolve those. So just to be safe, belt and suspenders, if you will, we are planning some active commanding that actually we're going to start today, where if it happens to be in one of these putative, complex fault modes, commanding may be able to get it out of. It has to do with the fact that the rover's clock will get scrambled because

of loss of power. This is not unlike at home when the power goes out in your home and you wake up and your alarm clock is blinking 12. And I'm late for work, right. And so that happens to the rover. So the rover doesn't know what time it is. And so it attempts to wake up at different times of day. And if it happens to be during when there's sunlight on the solar rays, it will try to communicate. But if it happens at the very end of that window when there's sunlight on the solar rays, it may think that it doesn't have enough time to communicate and shut down. And so there's like a 40 minute window

where that might happen at the end of the day. And so we intend to send commands to say, no, no, no, stay awake and try to talk to us. It's an unlikely situation, but it's not a zero probability situation. So we're going to actively command for a period of some weeks to make sure that that mode is not preventing communication from the rover. Your principal investigator, Steve Squires, he thinks it's a great plan, that this is the right way to go about this.

What happens, though, if let's say the dust storm is mostly finished, but Opportunity has, you know, an inch or so of dust on its solar panels. And what happens if on the 46th day, the day after you stop this active listening to deal with those possible faults, you get a nice little clean off from a dust double? We're not expecting an inch of dust on the arrays. A single monolayer of dust would be too much. That's why we're listening through January. If dust is preventing the rover from talking from us, a cleaning event, which might happen in the November to January timeframe as seasonally as suggested, then the rover may have enough power to wake up and talk to us. The active commanding that we're doing now is focused on a scenario where we have a lot of dust on the rover, but not too much, just a certain amount that allows the rover to power up a little bit, but not enough to allow it to wake up early enough to communicate.

It's an unlikely, but as I said, not zero probability case. So to your question, we're going to be listening. We have been listening. We intend to listen through at least January going to be listening. We have been listening. We intend to listen through at least January. We're listening at every single opportunity. We actually even listen in on other spacecraft's communication with Mars just to see if we might pick up a signal. Did that have something to do with this false alarm that some people in the public jumped on something from the deep space network and thought, oh, my gosh, Opportunity is talking to us.

Turned out not to be the case. Right. There's a public web graphic that shows the activity of radio antennas of the Deep Space Network. It indicates when there's a signal being received from a spacecraft. We often get false locks. Often it's MRO, which is a much stronger signal. Mars Reconnaissance Orbiter, of course. That's right. So we may be listening for MER, but we lock up on MRO. And so if you're looking at that graphic, you'll see a lockup signal

and you say, oh, Opportunity is talking. But no, it was a false lockup on the other spacecraft. So that happens quite frequently. So it's not surprising that you might was a false lockup on the other spacecraft. So that happens quite frequently. So it's not surprising that you might get a false alarm like that. You know what I take from that, though? I think it is another sign of the tremendous affection that people around the world, of how much people care about this remaining Mars Exploration rover. of how much people care about this remaining Mars Exploration rover. And I think maybe you may have seen a little bit of that in the reaction to this plan to do 45 days of active listening. People really are attached to your little robot. Oh, indeed. And the people who work on the mission are very much attached to this vehicle.

You know, I could argue that of all the NASA robotic missions, this is the one that people have most endeared with anthropometric qualities. You know, we think of it as a family member. And it's a family member that's doing noble work, great work, historic work on the surface of Mars. And we, over the 14 and a half years, we've all become quite fond and quite attached to this little rover. And plus it's so darn cute. That's true. So yeah. And I see it, my team members, and I feel it myself. I mean, I've been quite anxious and worried since June 10th. Regardless of what happens to Opportunity,

it will be a very long time before another mission exceeds the kind of records that we've set on Mars, either in distance travel or years of exploration. And so that makes it truly historic. During this active listening period, when you will be beginning today, you said, this 45-day period where you're sending commands, is it more labor-intensive than just sort of passively listening, as you'll do, you said, into January? Yes, it is. The passive listening is performed by some automated equipment, and they're automated scripts that clock out over time. So it's very much hands-off. Whereas the active listening, we have to have a team that convenes several times a week and over the course of many hours builds a set of commands that actually get radiated to the spacecraft. And then we have to have a mission controller who works on Mars time, who radiates

these commands and we plan to send them seven days a week, so every single day. And so that's a fair amount of workforce that has to sustain this commanding activity for however long we engage in it. The time may come when on this program we will salute Opportunity and Spirit for all of their accomplishments. But this is not that time. I want to concentrate on the positive and what we are all hoping will happen. If we hear from opportunity, maybe I should make that when we hear from opportunity, what happens next? It still will have gone through a very trying experience. And after all, it is a senior citizen. Yes, it is. And it will take some time to recover the rover.

You know, the first signal may just be a blip or beep. And it actually may be several days before we get the next beep from the rover. Once we can establish a communication pattern for the vehicle, we'll have to go through a process of bringing it back under normal sequence control. And part of that is resetting the clock so the rover knows what time it is, so it knows what time to talk to us. Once we bring it under sequence control, we also want to check to make sure that the vehicle is okay and ready to resume science exploration. So we want to make sure that dust hasn't affected the vehicle in some way. So we want to make sure that there's not too much dust on the optics

and that there isn't a concern with the actuators on the vehicle. So those are all things that will take some time to check out before we can say we're ready to resume. In the best case, opportunity goes back to doing science. After going 45 kilometers or nearly 28 miles, more than 28 miles, I think, and all these years, both Martian and Earth years, what's ahead on the rim of Endeavor Crater if opportunity goes back to work? Well, we were in the middle of a very exciting science campaign. We were on Perseverance Valley, and it's this sinuous valley structure, which from visual images looks like it might have been carved by water. The science team is actively investigating that hypothesis. Was it

water? Was it some combination of dry flows? Or was it aeolian or windblown effects that carved this valley? But for the future, beyond that, we were going to travel down into the inside rim, inside edge of Endeavour Crater, and go along that edge looking at the different geologic units that illustrate the different epics on Mars, the Martian history book, if you will. And to be able to explore those units will tell us a lot about the past of the history of the planet. Further south along the rim, there's actually an exit point where we can get back out onto the plains of Meridiani. And, you know, I wouldn't underestimate this rover. You know, there's still a lot of fight left in this vehicle, and there's a

lot of exploration we can do on Mars. John, you know how we feel at the Planetary Society, all of our members, and I'm willing to bet everybody listening to this program right now. We look forward to that moment, which could happen anytime now, I suppose, when Opportunity phones home and you can get back to work. All the best to you and everybody else on the team. Matt, thank you very much. That's John Callis. He is the project manager for the Mars Exploration Rover Project or mission, which is now awaiting and actively seeking out a signal from Opportunity, the rover that has already spent going on 15 years, Earth years, on the surface of the red planet.

Time for What's Up on Planetary Radio. We are here with the chief scientist of the Planetary Society. And I do mean here. We're in the studio, studio slash warehouse for the Planetary Society, because a lot of stuff has been taken out of storage in the last couple of days. And here it is surrounding us. Yes. If you hear growling, it's probably coming from those boxes.

Don't worry, they're air holes. Oh, man, I thought we donated those back to the zoo ages ago. Anyway, welcome back. It's good to be in the room with you, and we have some special stuff that'll be happening later. But first, what's up? Nothing special. Liar. Oh,, what's up? Nothing special. Liar. Oh, he's still got the cool planets.

But now Venus is starting to get kind of low. So check it out. Half hour after sunset or so, still low in the west, looking super bright. Work your way across the southern sky to Jupiter, looking bright. Saturn, yellowish. And Mars, still bright but dimming and looking reddish. And on the 20th of September, you will find the moon hanging out near Mars as it makes its way across the sky.

We move on to this week in space history. Last week was Star Trek, so it must be Lost in Space! Danger, danger, Will Robinson. 1965, the premiere of Matt's favorite show, Lost in Space. And then on a slightly different note, 2017, Cassini, End of Mission. Actually, I think Time Tunnel and Voyage to the Bottom of the Sea were my favorite Irwin Allen shows, but Lost in Spee, at least that TV show was better than the movie version.

Yuck. I didn't see it. You didn't miss much. Well, okay then. Now that we have had Matt's movie review, although I'm sorry, that TV show, that kid was so annoying, and that other guy, he was so annoying. There

was so much annoyance. Dr. Smith? Dr. Smith, I hated that guy. Well, you were supposed to. Oh, then I'm a good, I was a good boy. Yeah. Hey, you said we've got something special. And it looks like we've got some special guests in the studio. You want to introduce them? I do. It is regular listener Mark Little, who you hear us read some of his responses, his funny additions to the What's Up trivia quiz now and then. And it just happens that he and his lovely family are all here from Northern Ireland. Welcome, Mark. Thank you very much. Great to be here.

And here is the gift, which is going to live here. We're going to keep it. The boss has said it's all right to keep some hard liquor around. So we're going to save this wonderful bottle of Bushmills Irish Whiskey. What else? We wanted to recruit you for the

Random Space Factor. Are you up for that? Yeah, I think we can do that. What do you think, guys? Yes. Yeah? Yeah. Bruce, take it away. All right. One, take it away. All right. One, two, three. Random Space Fact.

Thank you. Well done. Well done. And you're headed home today. Have a great trip. Thank you very much, Steve. It's been a fantastic time we've had here. And thanks for letting us come in and see the studio and everything.

On to the Random Space Fact. We have the Dawn mission winding down after its spectacular voyages. So I thought I'd give a little Ceres information. The asteroid or dwarf planet Ceres was named after the Roman goddess of agriculture, corn, and harvests. The names of craters on Ceres are named after gods and goddesses of agriculture and vegetation from world mythology. And the other features after the names of agricultural festivals around the world. I really got you with that one, didn't I? I did not make that up. It's getting really tough. I mean, what are they going to do? There's still

so many other craters and features to be named. I mean, they're going to be, what, doing amusement parks and maybe my name. Funny you'd mention that. We'll come back to that. But we actually did a trivia random space fact related activity a while back for, I believe it's, I'm trying to remember. I think it's Gaspare. It might be Ida. The asteroid is Spa Towns.

Yeah, I do remember that. Anyway, shall we move on to the trivia contest? Please. All right. I asked you, what is the closest black hole to us? How'd we do, Matt? This got a pretty good response, though fewer jokes than I expected. Well, there are black holes.

And there were a couple of people, actually, who said every joke that will ever be made or can be made about black holes has already been made. But we still got a few from some people. Wow, now I feel like it's a challenge. Bob Klain was chosen by random.org this week. He's out of Chandler, Arizona. We hear from him a lot, but he is a first time winner. He says he listens to the show by Cybernetic Implant, which I really got to get one of those. They are wonderful. I speak from personal experience. The closest black hole he says we know of is V616 Monocerotis, which sounds like something you'd need a lot of bed rest to get over. Also known as V616 Mon, it's located about 3,000 light years

away. I guess that's a good enough distance. I wouldn't want it to be any closer. Is he right? That is correct. Also comes with other more exciting names like A0620-00 or 1A0620-00. 20620-200. Let's go back to Monocerotus. That is named after the constellation it's in, Monoceros, which in Greek is black hole. Oh, is that right? No, I totally lied. It is unicorn.

I was going to say mono-something is single horn, right? Okay, that makes sense. Wow, way to know language. Good job. Matt the linguist. We're going to send Bob a Planetary Radio t-shirt, which you can check out, as always, in the Chop Shop store, chopshopstore.com. And that's where the Planetary Society store is. It's a store within a store. And a 200-point itelescope.net account,

that worldwide network of nonprofit telescopes. I guess it's a worldwide nonprofit network of telescopes, actually. You know, I've been saying that you can donate that account if you don't want to use it yourself. We've always said if you have someplace in mind, a school or a nonprofit, well, we now have cut a deal with Astronomers Without Borders. In fact, we are going to be sending a recent winner's account to some schools in Puerto Rico, who I am told don't have telescopes, and they do have the internet, though, and they're going to be able to make good use of these. So

we're very grateful to that winner for donating this and to Astronomers Without Borders for sending it all up. That is excellent. It's a nice program. So now here are some other responses. The first one from Brian Mangold in Maricopa, Arizona. Clearly, the nearest black hole is the one where all my space trivia contest entries wind up. Except that one, apparently. Except this one. Similar from Mel Powell, who we hear from a lot.

He says, anyone who gives any answer to closest known black hole other than my sock drawer or the space under the driver's seat in my car is lying. Did he say just the sock drawer? I would say the dryer because that's where my socks disappear. How do you know where your socks disappear? I don't. That's a good point. Do you know about this, that there was a transmission?

We got this from Pietro Carboni in Chester, New York. An ESA radio telescope transmitted a signal in honor of Stephen Hawking toward this very black hole. That signal will reach there in roughly 5,475. Be there! Which doesn't make much sense if it's 3,000 light years away. I don't know. It must be slow, a very slow signal. Maybe it's an approximation.

Maybe something's moving. Maybe there's an approximation. Maybe something's moving. Maybe there's jello between us and it. I like the jello explanation best. That seemed like the most realistic. It just took me a couple minutes. Everybody knows light travels slower through jello. That actually is true. No, really, it is.

Finally, our poet laureate, Dave Fairchild. Haven't heard from him in a couple of weeks. V616 monocerotis is the closest spot where you have some light and then you suddenly have not. It's not a supermassive hole, but if you ever tried to get too close, you'd find that you had been spaghettified. That was a challenging set of words to try to rhyme together. I think we're ready to go on. It is time once again, as you may have guessed, to play Where in the Solar System? So I periodically, I always try to find out if anyone's named a feature after you, Matt,

and they haven't. But I did the closest I could come up with, Matt, with one T, but with an H on the end. So here's your question. Where in the solar system is a crater named math? Like mathematics, but it's not mathematics. It's a crater named math. Where is it? Go to planetary.org slash radio contest. Thank you. I love it. I did have a couple of friends who used to call me Math. They're not my friends anymore. Okay, Math.

Nice try, but you're not getting off that easy. You have until the 19th. That's September 19th at 8 a.m. Pacific time to enter this one. You might win a Planetary Radio t-shirt, a 200-point itelescope.net account, and because our previous winner of one of those Distant Suns VR codes to get that wonderful app for free, I've been playing with it. It really is cool. He's not an iOS guy, an iOS guy.

He's got an Android phone. So he said, why don't you give it to somebody else? So if you have an iPhone or an iPad, one of those iOS devices, we will happily add that to the prize package to whomever wins this week. We're done. All right, everybody, go out there, look up the night sky, and think about what's stored somewhere in a box in your house that you haven't thought about in a long time. Thank you, and good night. We're in a box in your house that you haven't thought about in a long time. Thank you, and good night.

We moved two years ago, and there are still boxes in the garage that have mysteries awaiting us. Yeah, I still have boxes from grad school. Okay, you win. The winner is Bruce Betts, the chief scientist for the Planetary Society, who joins us every week here for What's Up. Planetary Radio is produced by the Planetary Society in Pasadena, California and is made possible by its members who are the Martians. Mary Liz Bender is our associate producer. Josh Doyle composed our theme, which was arranged and performed by Peter Schlosser.

I'm Matt Kaplan, Ad Astra.