Planetary Radio • Jun 26, 2019

The News From Saturn-With Linda Spilker

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Linda Spilker

Voyager Mission Project Scientist at NASA's Jet Propulsion Laboratory

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Bruce Betts

Chief Scientist / LightSail Program Manager for The Planetary Society

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Mat Kaplan

Senior Communications Adviser and former Host of Planetary Radio for The Planetary Society

It has been many months since the great Cassini spacecraft plunged into Saturn’s atmosphere and fiery death. Yet the mission lives on as the reams of data and images reveal much more of this beautiful world, its rings, and its moons. Project Scientist Linda Spilker is back with Mat to provide a fascinating update. We close with Bruce Betts and a What’s Up segment that anticipates the mission of LightSail 2.

Saturn's ring-embedded moon, Daphnis
Saturn's ring-embedded moon, Daphnis A false-color image mosaic shows Daphnis, one of Saturn's ring-embedded moons, and the waves it kicks up in the Keeler gap. Images collected by Cassini's close orbits in 2017 are offering new insight into the complex workings of the rings.Image: NASA / JPL-Caltech / SSI
Cassini's 'Last Dance': A final portrait at Saturn
Cassini's 'Last Dance': A final portrait at Saturn In the early afternoon of 13 September 2017, the venerable and much-loved Cassini probe captured this final portrait of Saturn and its main ring system, before plummeting to fiery destruction in the planet's hazy atmosphere just 48 hours later. Using its Wide-Angle Camera (part of the Imaging Science Subsystem), Cassini snapped 75 photos: these images can be grouped into a grid of 6 by 2. Each footprint in that grid was covered with both long and short exposures via the red, green, and blue filters, plus a longer exposure shuttered through the clear filter. The veteran spacecraft took nearly two hours to collect these data: starting at 1:09 PM and concluding at 3:17 PM (all times are UTC). Only three moons—Enceladus, Janus and Mimas—can be picked out in the uncalibrated and compressed data.Image: NASA / JPL-Caltech / SSI / Ian Regan

This week's prizes:

A priceless Planetary Society KickAsteroid rubber asteroid, a 200-point astronomy account AND Apollo, the beautiful graphic novel about the mission of Apollo 11, by Fitch, Baker and Collins.

This week's question:

What does the label of the Mini-DVD on LightSail 2 say? It contains the names of all Planetary Society members and others, along with selfies.

To submit your answer:

Complete the contest entry form at or write to us at [email protected] no later than Wednesday, July 3rd at 8am Pacific Time. Be sure to include your name and mailing address.

Last week's question:

From what type of spacecraft will the six COSMIC-2 spacecraft launching with LightSail 2 draw their signals from in order to study the Earth’s atmosphere?


The answer will be revealed next week.

Question from the May 30 space trivia contest:

Where in the solar system is a feature named Dogana?


We played “Where in the Solar System?” to learn that Dogana is a large crater on Mars.


NOTE: This automated transcript is currently being edited by a human. Check back soon for updates.

[00:00:00] The latest news from Saturn with Linda's bilker this week on planetary radio.

Welcome. I'm at Kaplan of the planetary Society with more of the Human Adventure across our solar system and beyond a slightly abbreviated show this week as I prepare to leave for Florida in a few hours. I'll be joined by many of my colleagues hundreds of planetary Society members and thousands of other space fans headed to the cape for the launch of the third SpaceX Falcon heavy among the 24 payloads carried by that big rocket is the planetary societies like sale to actually by the time you hear this.

We hope lightsail to will be safely in orbit. With our successful static test on the evening of June 19 launch is set for the late evening of Monday, June 24th, but you know how launches are anyway, I've got a great way to distract you and myself [00:01:00] from our attempt to orbit a solar sailing cubesat.

Linda's bilker is still my most frequent guest on planetary radio. She is the project scientist for the cassini-huygens mission that ended on an early September morning in 2017. Or did it you almost wouldn't know judging from the amount of science that is still flowing from the missions data and much of that science is spectacular Linda as always a pleasure to welcome you back to planetary radio, especially here in the planetary Society Studio.

Happy 15th anniversary of reaching Saturn with Casino. Oh, well, thank you very much Matt. It's a pleasure to be here. I surprised you with that why you did I looked it up and I was surprised to see that. It's that nice nice anniversary and we can celebrate by talking about the great science that continues to flow from this Mission, which has been vaporized in the saturnian atmosphere for a year and a half now, that's right.

That's right and yet the [00:02:00] analysis of the data continue. There's so much. We're still finding its this Treasure Trove. Data sent back by Cassini and we've learned so much more about the Rings the planet. The icy moons and lots more to come we last talked in October. It was right after another of these big releases of data in papers that were published in Science magazine.

There must be other journals that are very envious that could be mad that could be so we talked about all the stuff there and now you've got new science. It's kind of a shame. We haven't talked sooner than this because. So much has been going on and the big one that I think captured more popular media attention.

Not just you know, folks like us who are Science and Space Geeks was that January 17 publication in science. The one that really made a splash because it told everybody that the Rings are what relatively. That's right. [00:03:00] Matt. The Rings are much younger than the 4.5 billion year age of the solar system.

In fact, there may be only ten to a hundred million years old. Maybe the Rings formed. Around the age of the dinosaurs imagine dinosaurs looking up at all of a sudden. Wow. Look that planet has right. Well, I was thinking that you know Humanity we're kind of lucky that we've reached this stage where we have telescopes and and there they are.

I mean we could have missed this if we been off by 10 million years in our Evolution, that's absolutely right. In fact, the Rings are slowly decaying particles are getting lost to Saturn to space and maybe another few hundred million years. They might be gone how critical to that Discovery was getting in close to Saturn.

Well, the only way Matt we could do that was to dive through the gap between the planet and the Rings and make very sensitive gravity measurements of [00:04:00] Saturn and the Saturn on one side the rings on the other feeling that those minut tiny tugs and from that we could actually then. Figure out the mass how much material would be in the Rings If you scoop them all up and form them into a moon.

So do we now know not only what the Rings way what their mass is really but the massive Saturn itself, right? We know the mass of Saturn very accurately as well as the Rings and what's surprising is the Rings were only about 50% as massive. As we expected a lot of the scientists we even had a little pool how massively the Rings be and a lot of people are saying more massive than the estimates made by Voyager.

And so they just turned out to be much less massive. Pointing to a younger age, huh? How will we far-off? How was it that so many people were thinking that if we were wrong we were wrong in the other direction that they were more massive than we thought. Well the [00:05:00] puzzle came with the most massive ring at Saturn the B ring and we got estimates of the mass from looking at how waves dampen the Rings but the B ring was so thick it blocked all the Starlight.

It blocked radio waves so we couldn't do. Luckily estimated Mass. So we just said, okay. It looks like it's so thick it must be very massive and that's where our estimates came from but it turns out there must be something else going on because that ring is not nearly as massive as we expected so somehow the particles are interacting with each other to block Starlight block radio.

And yet not be quite as massive a good example is if you think about a swimming pool full of water, you can look through that water see the bottom of the swimming pool and yet that water has a lot of mass now. Imagine a very thick fog that very thick fog will keep you from seeing say to the next house or down the street and yet there's far less [00:06:00] water in that fog.

It's just because of how those tiny little droplets of water are reflecting or absorbing. Light so maybe some kind of an analogy like that's going on in the B ring. It's not you know, the more massive like the water in the pool, but instead somehow more like a fog. Obviously the science keeps building on itself.

You keep adding to what we've learned if we move on to March again in Science magazine, March 28, all these new findings about these five tiny moons that are in and near the Rings again. We now know so much more because you were able to take a chance at the end of the mission and fly in there close.

This has been full of surprises to I think you found that in solidus has some influence their to absolutely Matt and turns out that before we hopped across the Rings and flew through the Gap. We [00:07:00] brought the orbit in very close to the outer edge of the F ring and by getting in close we could time it then to get our best ever images of.

These tiny ring moons two of them are in gaps pan is in the Yankee Gap daphnis in the Keeler Gap. Atlas just outside the outer edge of the a ring and then Pandora a couple of the other moons as well. And we found much to our surprise that these little tiny moons look like world's that there was a central Shard or Central object, but then it had these big skirt.

Ring particles around the moon the Rings are only on average maybe 10 feet thick and so these ring particles accumulate around the equator, 's giving them kind of look sort of like a ravioli or maybe a ballerina in a skirt or something. I saw that term used. I know it was a quote from your colleague Bonnie buratti who led a lot of this work that led to this publication in March.

So like a like a big belt around the middle of these [00:08:00] little Little Moons that's right made completely of ring. Collison that that belt or that skirt can only grow so large until it gets to the point where Saturn's gravity is just balanced by the moon's gravity and so particle just won't stick any longer.

So the skirts grow to a certain characteristic size. We found that the the skirts and the moon's themselves are have a lot of porous a lot of empty space, you know, maybe half of it is empty and then their colors depending on where they're located if you're in the. Kings and of course your reddish in your colors look a lot like the ring particles but as you move away from the Rings those tiny particles from the earring and from Enceladus play more and more of a role in so those moon start to get Bluer especially on the side that sweeps up.

The particles from Enceladus. So we're seeing this really fascinating interplay between the Rings and the moons and also with the earring in the particles coming in from [00:09:00] Enceladus. I'm glad you mentioned that that variation in color because there is an illustration will link to all the press releases the media releases from JPL about all of this stuff and there is one where it's Zooms in on one section of the Rings and there are these beautiful someone enhance.

There's a little bit of false color stuff going on. Right. Yes, you're looking across the Rings and it's it's a it's it's own sort of rainbow. It's very amazing. It's the Keeler Gap and you see Tiny daphnis orbiting in the Gap and it's pulled a small tendril or ring particles away from it. And the Rings are very reddish As you move towards Saturn and yet outside of the Keeler Gap, they become grayer and grayer looking like a very different ring.

And so we're puzzled about. What's causing that change that abrupt change right at the Gap in color and then daphnis is so fascinating its orbit is inclined just a little bit related to the ring plane and [00:10:00] it creates tremendous waves on either edge of the Gap and the waves not only move in and out relative to Saturn but up and down as well.

So imagine surfing on this giant daphnis wave of ring particles lifted above and below the ring play. I was going to bring it up in a couple of minutes. But because you're talking about daphnis. I mean there is this image not in the March release but in the June 1 and will be coming to that. It's this breathtaking image of daphnis this little not quite rock that is shaping the Rings Edge like a world-class sculptor and it is just so beautiful.

Yeah, it's absolutely stunning. You can see three wavelengths of that wave and the final one the most distant from daphnis. You can actually see the way of separating from the Rings as it gets lifted above and below and then very slowly damps out like waves on a beach until daphnis comes around again.

And the process [00:11:00] starts over instead of just a link. I mean, we'll do the link as well. But we'll probably put that image on this week's show page. The people will find a planetary dot org slash radio, but. I was looking at it again on my train coming here this morning and there was this little wisp around daphnis and I thought is this smudge on my on my iPad screen.

And so I moved it back and forth and I said no that's part of the image. What was I looking at? There was this tiny wisp almost like a tiny little section of a ring around daphnis itself. Right? Daphnis is gravity had pulled some ring particles away and it made this little curved piece of array right next to deafness just beautiful probably some of them are falling onto deafness and and made some of the skirt that's on deafness as well back to the color.

You talked about it being read. On the inside edges of the Rings. Why red is that iron oxide or something? What are we looking [00:12:00] at there that composition that called causes? The redness is really a good question. We know that the Rings are mostly water ice. We've seen silicates now in the ring by diving through the Gap and also some complex Organics that were measured so it could also be tiny grains of iron giving it its reddish color.

So we're just not completely sure we know. We saw in the Gap but are though that same material than much much further away from Saturn. And so we're still puzzling because the spectrometers the instruments that measure. And look at the composition didn't see Organics and rings and if there's a lot of Organics there we should have been able to see it none of those in and this is the term that has come up several times in recent months on the show The tholians those complex Organics that seemed to be like down on Titan.

Yes, but you just didn't the instruments didn't see these right the the [00:13:00] spectrometers the instruments that measure from a Faraway. Sensing didn't see them but the instruments that flew through the Gap and measured its it you one of those instruments did see Organics in the grains and the gases that it measured we can talk about this at any point in this conversation.

But what you seem to be indicating already is that as much as Cassini has told us you must be dreaming of it yet another mission. Oh, absolutely it would as with any mission. Reveals all of this very interesting data. There are so many open questions that invariably you say I want to go back, you know a mission to fly through the Enceladus plume and look for those big molecules that could indicate life Reven land on the surface and send something down into one of those vents mission to Titan.

There's a proposal in New Frontiers for something called dragonfly. We've talked about it several what copter Titan [00:14:00] would be so cool and to learn. Or about what's going on in those methane lakes and seas and could you have a very very unusual kind of life that could live? In liquid methane at very very cold temperatures then of course, there's the Rings.

We actually came up with an orbit after Cassini where you could literally skim across the Rings Titans orbit is slightly inclined orbit in the same plane as tighten and you could then get very very close to the Rings. In fact, I think a great dream would be maybe to have a spacecraft that could hover above if like ion propulsion or something hover above a patch of ring and.

Watch individual ring particles interact and look around to propeller and how to propellers grow and why are some places in the Rings clumpy and some places streaky and some places kind of look like strong really understand that that disco particles. There's a lots of analogies for the disc of particles at Saturn in [00:15:00] Hell our solar system might have formed how mass comes together to form planetesimals.

For our own solar system and for exoplanet systems as well. So lots of Clues there. We just have to be really good detectives and go back so you I think you know that I'm something of a Trekkie and I had mentioned to you before we started recording today that I asked you. Do you remember it had you seen the opening title sequence for the old Star Trek Voyager and there is a scene in that when Voyager?

Making its way across the Galaxy and they are skimming right above the ring system of some Planet. So close that you can see the reflection of the spacecraft in the ring itself on the ring particles. I don't suppose you're talking about getting that close, right? No, not quite that close. Although it would be tempting to just see how close could you get because the Rings in general are only about 10 feet thick except when you have waves like the edge of.

Now the deafness creates or some of these bending ways, but mostly they're pretty thin. It would be really cool to [00:16:00] see ring particles up close. You don't really get a great portrait of what's going on in the Rings and kind of get into their their DNA a little bit. If you will Ten Feet 3 meters is one of the most amazing it every time I hear that that's roughly how thick the Rings generally are.

It is maybe one of the most amazing things that. That I hear about the saturnian system obviously adds to our Fascination, right? Yeah, just sort of that sort of an average thickness and places. It could be much more course propellers could be half kilometre or kilometer in size these biggest particles in the rings that are trying to open Tiny gaps and what these final pictures in the final paper we got.

Some very good very close pictures and and more data on propellers and how they work and what they look like up close. Now are you talking now about this recent publication date in the June issue June 13 in the journal science, once again more amazing [00:17:00] stuff. I already mentioned that that image of daphnis which really folks you have to take a look at there is another one though.

And it's a slider so you can interact with it and it you know has an image of the Rings that hat was previously published. Right, but if you slide it to the left, you see this fantastically complex image to tell us about that right when you slide it. You're seeing a processed image where it's in particular looking for any structure.

As smoothly as you go around the ring and by doing some special processing techniques can start to see this these belts of streaky material or clumpy material or straw-like material built for there's a lot of clumping your may be growing larger and larger strands of ring particles or bigger ring particles and the band's end abruptly on either side and then you go to a place where it doesn't look like there's much clumping at all and then you'll jump to something else and there's no.

We are [00:18:00] obvious connection between boundaries. Why do you have these boundaries of clumpiness? And why is it in some places in the Rings and yet not in others. And so we just have now a long list of new questions. How does this work? Why is this clumpiness going on and we're starting to think it's probably a difference with the surfaces of the particles, huh that may be behind how they Collide and interact maybe the somehow the roughness those grains.

Regulus grains on the outside of the particles. Perhaps could have some influence on how they stick together and how the clumpiness works, but we just have a lot of ideas and still trying to come up with a good model for how this works. Is there enough data that. Some people out. There are maybe building mathematical models that that would help to explain this.

I'll absolutely mad at you know, as we got more data about propellers about the clumpiness. The modelers are [00:19:00] happily going back to work and trying to incorporate. This new information into their models. I also read that there was information about revealed about impacts and that we may be understanding better.

What it is that periodically stirs things up impacts on the Rings themselves right will how those impacts might generate a lot of dust in a certain region. We think maybe in the d-ring one of the Ring. Brightened perhaps that's evidence of an impact and maybe as we were flying through the Gap some of those particles is what we saw that got close to Saturn Saturn's atmosphere slowed them down and then they finally went into the atmosphere these tiniest smoke sized particles that were filling the.

As Cassini dose through 22 times those smoke like particles nanoparticles. So tiny that caused so much anxiety before Cassini [00:20:00] went through the gap for the first time and it turns out you had nothing to worry about absolutely we didn't know in fact the first orbit. We used the high-gain antenna that big dish antenna as a shield to take the particle impacts in case there were millimeter or bigger part.

It's in there and then we found that we really didn't see much of anything until finally the particle detector said hey, they're really tiny like Nano grain size. And we said, ah, we can fly through smoke sized grains, and then we went on to do all of the science we needed to do we no longer had to worry about.

Pointing the high-gain antenna into the direction of those particles which which meant that you couldn't use some of the instruments right as you went through the Gap because the dish was blocking. That's right. That's right as in particular for getting samples of those particles. You really want to turn the spacecraft 90° and point those instruments into the incoming ring particles back to those impacts.

What is the thinking now about where that [00:21:00] material is coming from? Is it coming from outside of Saturn or is it is it stuff that was already there the nanograins we saw they're all in the same plane as the ring. So they're coming from The Ring. Something is ground up. The ring particles may be removed a lot of the water and just left the silicates and other materials are still water there as well.

But it allowed us to see the Organics and other material and then is that boundary is the atmosphere of Saturn is thick enough. It just slows them down and then they fall into. Some of the other tiniest grains in the A and B and C Rings, they get charged up by Saturn's magnetic field. They can spiral along field lines and they go into Saturn at different latitudes on the planet.

In something we call ring rain. Yes because we can see in these latitude bands. There's water and that water is coming from Saturn's rings. Wow. And the first thing I thought I had it occurred to me before but talking about those spiraling particles going [00:22:00] in it sounds almost as if you were looking at a cloud chamber on the end of some particle accelerator because of the same kinds of things happening you're reacting to a magnetic field right is just as great to verify.

Then in those final orbits Cassini flew across those magnetic field lines and could directly measure the particles how many of them and what they were made of so we got a close-up look to sample and taste the ring, right? As we see these things happening in the Rings and for example that clumping of material around the midriffs of those little moons is Saturn helping us to understand how our solar system and other solar systems may have been formed exactly right by understanding how these particles stick together how they interact in a disc all of the things that go on.

Give us Clues to what that huge protoplanetary disk of material [00:23:00] look like and how clumps of material grew their that eventually became the planets and we can apply that. To our solar system and EXO planets solar systems as well. So before we talk about the future, what have I missed what stands out?

I think what stands out is just how much we still don't know how long the list of questions still is and there are many scientists happily working away probably will continue to do so for decades to come to look at through that data set and learn more about. Planet the moons and the Rings themselves and yet do you ever stop now and then and think about how much we didn't know and now do know if you look back just 15 years when Cassini was arriving at?

When Cassini first arrived at Saturn we were literally standing on the shoulders of Voyager because we had the two Voyager flybys of the Saturn system [00:24:00] and a Pioneer fly by and we thought we had lots of answers. But still what was the source of the e-ring Cassini found Enceladus with a liquid water ocean underneath its icy crust.

We thought the Rings were individual particles gently colliding and now. Most of the Ring material clumps together in very very unusual and unique ways. The Rings are young just so many things tightened seeing the surface for the first time with the Huygens probe landing on the surface and finding methane lakes and seas and River channels and dunes of tiny particles that grow in the upper atmosphere.

So many things that kind of like, you know, you may be in a sense that with wager we got closer to the cover of the book and Cassini is now open. Looking through the chapters and the pages of that book and there's so much more to read this. That's right so much their new books to write. In fact many new books have come out about from Cassini with Cassini data.

There's a book of new book about [00:25:00] Saturn a new book about planetary Rings a new book about the icy moons and Enceladus. So we're in a sense rewriting a lot of the history and a lot of what we thought we knew before Cassini. You've sort of touched on this but what is currently on the frontier? What is the research that's underway.

Now that will continue to build on this data. There's research in particular about Enceladus and how those jets work and come out of the surface come out from Enceladus to think about if we were going to land someday. He'd want to know as much about what is coming out and how close could you get and what kinds of instruments would you want to take for some kind of a Lander mission on the moon Enceladus?

Same thing for Titan looking in detail at those data. If you're going back to tightened say with an Orbiter and maybe something to land on the surface. What questions and what things do you need to know about Titan how the winds blow if you go down to the surface [00:26:00] who answer those questions as well.

You must be very excited about this possibility of dragonfly that little autonomous drone going down to maybe explore the shores of Titan. That would be so dragonfly if it's selected in NASA's New Frontiers program. It would be such an exciting mission to really then be able to move to different locations on Titan and take that one place that we know from the Huygens probe and start to really understand what's going on on Titan and.

Dragonfly I'll be carrying the instruments that we've learned as we've learned about Titan with Cassini that will help answer additional questions. So hopefully a few months from now we'll know if dragonfly is the the mission selective. Yeah, we're getting close and of course, we don't play favorites at the planetary Society.

We wish that there was money for all of the missions that are in this current round of competition because they all have tremendous value, [00:27:00] but there certainly is something especially exciting about. Sending a flying machine to another. Oh absolutely just yet. This is the picture of a quadcopter Landing tightness.

Just it's really a cool Mission. Well, what else is keeping? You busy? I know that you're getting ready helping to put together one of our favorite events around here one that my colleague Emily locked abhaile. Never misses. Oh, yes that what's coming up is the DPS or division for planetary Sciences meeting this year.

It's a joint meeting with our European colleagues. It will be held in Geneva. It's your land and it's going to be a huge meeting where planetary scientists from around the world come together talk about their newest results their newest science and look forward to Future missions as well. And as chair of the DPS.

I'm helping plan and organize that. And it's going to be a great meeting that because now you have slightly more time than when you had a spacecraft orbiting Saturn. Right right. [00:28:00] Now the Cassini is you know, that we're looking through the data. There's a bit more time to try and get the scientists together to talk about and encourage them to look at the data.

Linda may not be quite as frequent as it was when Cassini was still sending back data, but we will continue. I hope to have these conversations certainly. By the time of DPS because I bet there will be more research released at that time by your team when they meet with all their colleagues in Geneva.

Right ran. I just want to add one more thing along with the science papers that came out. There's a special issue of the geophysical research letters, probably 40 or so. Additional papers on Cassini data, they've been online for a while, but now there's a special print issue that's available with additional papers a lot of them about this final year of the mission in particular the grand finale May the science continue to flow over the decades to come.

I'm [00:29:00] sure it will yes. I I certainly hope so thank you Linda. Thanks, man. That's Linda spill core project scientist for the cassini-huygens mission. Telling us about the latest and stay tuned because there is much more to come it is time for what's up on planetary radio back with me is the chief scientist of the planetary Society.

That's a Bruce Betts. Dr. Bruce Betts. Welcome. Thank you. Good to be here man. How you doing? I'm fine, and I only wish because we're having to record this. Before June 24th because I'll be in Florida because everything will be happening in Florida. We don't know if lightsail has launched or not.

We'll just have to keep our fingers crossed. I will still dare to talk about a light selling this in this time period. I invite you to proceed and begin with the night sky. All right in the night sky got Jupiter in the evening up in the East looking like a super bright [00:30:00] star and Saturn coming up on Saturn Opposition opposite side of the Earth from the Sun.

So it's rising just a little after Sunset now, it'll pretty much be rising around the time of sunset when it reaches opposition in July. It's a total solar eclipse time. That's right. Or eclipse on July 2nd and that will be visible from parts of the South Pacific and Chile and Argentina at least totality much of South America will see a partial solar eclipse.

Yeah. I know our recent guest jpas a coffee is going to be there in Chile waiting for I don't know something like his 40th total eclipse. She's amazing this week in space history 1908. Tunguska impact is much forest from that asteroid impact airburst as 50% larger than the city of Los Angeles. It was a it was pretty big.

Lot of Timber quite the [00:31:00] reminder of hey we need to do something about planetary defense Asteroid Defense. Hey, by the way, I've got an asteroid defense class online. You can find it courses dot planetary that organ only take you about an hour and you'll be a super Asteroid Defense smart and it's free right?

It's free. All right, we move onto one bums spins fact. So white sale to when you're building a spacecraft and you really want to think about it working. It's good to plan for contingencies. So we've actually built into light sail to which lights I want to not have a number of software timers that check things and figure out if process is need to be restarted or even the spacecraft rebooted but we also have a hardware timer so built into the hardware.

There is a timer that a little more than 12 days into the. No matter what's happened or happening. It will reboot the spacecraft because you know rebooting your computer tends to fix [00:32:00] stuff. Yeah. I keep telling my wife that you need to build in a timer to the just automatically reboot. That's a good idea.

We keep saying that light sail is the size of a loaf of bread. Does it make toast? Yes, it does but no one can eat it it in space. No one can eat your toast. That'll be a great tagline from movie. I'd be scared to think what that movie might be about but it would be scary. Yeah, we move on to the trivia contest I and we were playing we're in the solar system.

So we're in the solar system is a feature named die gotta hide we do man. I know you're going to stick with that canine pronunciation of this but I do think based on the responses. We got it's probably dogen. Because it seems to be based on some place in Italy. We'll get to that Alex Schumann. He says [00:33:00] it's a crater on Mars.

That is correct. 41 kilometres on Mars. Congratulations Alex first-time winner. He listens to us on W. MF e Orlando not far from where light sail will begin its historic Mission or maybe already has begun. He is one a planetary Society kick asteroid rubber asteroid 200-point. I telescope dotnet astronomy account and a terrific book for young people this the Space Race by Sarah cratis beautifully illustrated book for young people about human space exploration and more.

It's really delightful itself full of great illustration. So congratulations Alex. Can I read you a few more? No, please do this is from our friend Claude Playmate at the Big Bear solar Observatory here in Southern California to Ghana is a beautiful Martian crater perfectly situated just north of the Valles marineris.

One of [00:34:00] the wonders of the solar system with superb views towards the outflow channels. This property is located at a temperate 10 Degrees South giving it some of the best weather on the planet as well as plenty of solar exposure for your photovoltaic Farm to Ghana is a perfect place for year round living the 41.2 km/h amateur crater has plenty of room for your growing Colony come for the views stay for the weather.

I'm so the problem is well, it's not there anymore. But as Laura Dodd and a few other people pointed out it apparently used to have a lake at least that's what a lot of researchers think a Paleo Lake which is a nice way to put it I guess our Poet Laureate. I'm going to forgo his poem this this time because he provided such great information.

About this crater and its namesake on Earth southern hemisphere of Mars on Earth. This location would be on the eastern coast of [00:35:00] Brazil. It is named for the largest town in San Marino that little tiny Nation. That's totally surrounded by Italy how small is it of Interest the entire country of San Marino would fit inside the crater 27 times with room to spare crave random space fact within the trivia.

Indeed. I got one more and this will be our poem for the week. David do that in Charlestown West Virginia sent us this on Mars. They might ask if you want to go sightseeing at Crater dogana where a lake used to be. But today you won't see any water nor Flora nor fauna. Nice work David. Thank you very much.

Got another one for us. I do there is a mini DVD on light sail to the contains the names of all of our planetary Society members Kickstarter backers and people who signed up send their names or selfies to space Here's your question. [00:36:00] On lightsail to what is the label of the mini DVD? Say what are the words on the label of the mini DVD go to planetary dot org slash radio contest.

You have until the 3rd of July the day before independence day here in the US July 3rd at 8:00 a.m. Pacific time to get us the answer this time with somebody is going to win. I promise a 200-point i telescope dotnet account worldwide network of telescopes. Anybody can use if you have an account to look at stuff all over the universe a planetary Society kick asteroid.

Rubber asteroid had trouble getting my engine started and let's see. How about another book Apollo the graphic novel, which is it's very cool. I have read it all I have it here and that's the copy that will make available. It actually does a fantastic graphic [00:37:00] visual job of documenting not just the mission of Apollo 11, but to a degree the lives of the three astronauts and interestingly enough.

One of the guys responsible one of the three authors of this graphic novel is named Mike Collins. Not that not that my Collins but definitely Mike Collins Michael Collins. We are ready to finish her off. All right, everybody go out there. Look up the night sky and think about where you'd buy property on Mars.

Thank you and good night. I'm gonna I want the top of Mount Olympus because you know, why because that's where according to Kim Stanley Robinson. They're going to put the bottom of the space elevator. So that property is going to be worth a lot. Oh, yeah, that's a Bruce Betts the chief scientist of the planetary Society.

He joins us every week here for what's up planetary radio is produced by the planetary Society in [00:38:00] Pasadena, California and is made possible by our anxious yet. Thrilled members. Would somebody tell me if the launch went. Okay, Mary Liz Bender is our associate producer Josh Doyle composed our theme which was arranged and performed by Peter Schlosser.

I'm at Kaplan. Ad Astra and go light sale.