Planetary Radio: Space Exploration, Astronomy and Science - Pluto Occults! Join Us on the Mountain

Episode Date: August 22, 2018

Pluto passed in front of a star on the evening of August 14. Mat Kaplan joined pro and amateur astronomers on a mountain to observe this rare event. It may reveal more about the dwarf planet’s tenuous atmosphere and other properties. Everyone hopes that Mars Exploration Rover Opportunity will phone home when the waning worldwide Martian dust storm allows the robot to charge its batteries. Digital Editor Jason Davis tells us about the online mistake that had some fans believing it had already happened. And it will be “raining fire in the sky” when Bruce Betts drops another What’s Up segment. Learn more here: http://www.planetary.org/multimedia/planetary-radio/show/2018/0822-2018-franck-marchis-pluto-occultation.htmlLearn more about your ad choices. Visit megaphone.fm/adchoicesSee omnystudio.com/listener for privacy information.See omnystudio.com/listener for privacy information.

Join me on a mountaintop as we wait for Pluto, 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. It's not an occult science, it's occultation science. On August 14th, Pluto passed in front of a star. Astronomers were waiting. I joined several of them, including the SETI Institute's Frank Marchese, as we waited for this cosmic event that would reveal more of the dwarf planet's secrets. The dust is settling on distant Mars.

Will we hear from Opportunity, the Mars Exploration Rover, when it is once again able to see the sun? Planetary Society digital editor Jason Davis wrote in a June 21st blog post about Internet fans of Oppie who jumped the gun. Jason, you called this piece false alarm. Here's why people thought Opportunity phoned home last week. You can't fault them for their what? Optimism? What's the word I want? We're all hoping to hear from Opportunity again, right? Yeah, I think so. I'm finding that opinions are starting to vary on whether we will ever hear from Opportunity again, but I think everybody

really wants to. A lot of people are really keeping tabs on the Deep Space Network to see if it's talking with Opportunity. Then, of course, there's a neat little dashboard called the Deep Space Network Now, where you can go and see what the Deep Space Network, what missions it's talking to at any given time. So people have kind of been watching that like hawks to see if we get in touch with Opportunity. And that dashboard is very cool. We've mentioned it before, and we'll put a link up on this week's show page, planetary.org slash radio. If all you went by was the dashboard, you could see how people might have been confused because it said MER, right?

Yeah, so it said MER1, which is the call sign for the Opportunity Rover. It was up on the board. And not only that, but it was communicating. There was a little animation of a radio wave coming from space down to the dish, so it looked like something was talking on the board. And not only that, but it was communicating. There was a little animation of a radio wave coming from space down to the dish. So it looked like something was talking to the dish. So everybody got really excited, or at least some people did on Twitter. There was a big to-do about it. But then NASA didn't say anything.

And then finally, some JPL folks, the JPL Media Relations Office, confirmed that no, in fact, Opportunity had not phoned home. And then, so everybody was asking, well, how did this happen? Well, it turns out that right now, whenever Opportunity does wake up, if it wakes up, it will try to phone home during these pre-selected fault recovery windows. And so whenever it could be phoning home, the Deep Space Network turns its dishes towards Mars and it listens. Now, unfortunately, there's a lot of things at Mars, and Mars in the sky is very small. That's not unfortunate, Jason.

That's true. Yeah, exactly. At any given time, a lot of things might be talking from Mars. Now, they use different frequencies, so if we're tuned in to hear opportunity, we shouldn't hear another spacecraft. But there's this pesky thing called the Doppler effect. You know, it's the same thing that causes an ambulance's siren to sound differently as it approaches you and then moves away from you. Anyway, as these spacecraft are moving around Mars, their frequencies are shifting because they're either moving towards Earth or away from Earth. And every now and then, those frequencies shift in a way that one of them overlaps with the frequency for the Opportunity rover. And when that happens, the Deep Space Network, if it happens to be listening, it will

lock onto that signal and say, hey, I hear something. And it will follow it for a little while until it shifts back out of Opportunity's expected range. So that's why everyone saw something talking to the Deep Space Network. And you gave the frequencies for Opportunity and the Mars Reconnaissance Orbiter. They're not too far apart to begin with. And you could see where a little Doppler shift might confuse things further. So we'll just have to keep our fingers crossed, I guess. I mean, what's the outlook? I hear the storm is waning. There's a technical description that NASA used for this saying, well, the amount of dust being thrown into the atmosphere is less than the amount of dust that is falling out of the atmosphere. Yeah. In other words, the dust storm starting to dissipate.

They use this kind of esoteric figure called tau to determine how thick the dust is at any given time. called Tau to determine how thick the dust is at any given time. They estimate Opportunity probably needs a Tau of less than two to come online and start getting power to its batteries. At the height of the dust storm, right before we lost contact, the Tau was up around 10. But recently, it's been down in the twos and kind of fluctuating around. So it is possible we could hear from it soon, assuming that it did survive the dust storm. So all we can do now, I guess, is just hang out and wait, see what happens. And hope. Thank you, Jason.

Great explanation. We'll hope that those skies continue to brighten and that Opportunity phones home soon. Thanks, Matt. Jason Davis. He is our digital editor at the Planetary Society. Davis. He is our digital editor at the Planetary Society, and you'll frequently hear him or see him writing about LightSail 2 because he's our embedded reporter with that project. Let's go out and watch Pluto occult a star. If you're in the right spot and you know where to look,

there are objects in the sky passing in front of other objects all the time. Many of you were watching a year ago when the moon passed in front of the sun. Well, it's called, in addition to eclipse, occultation. And it is frequently an opportunity to learn something about one or both of the objects. It was Pluto's turn on August 14th. The dwarf planet, or simply planet, take your pick, would briefly block the light of a far more distant star. Astronomers, both pro and amateur, were in position along the path from which this event would be visible. I set out to the northeast of San Diego, California,

heading toward Lake Henshaw, or rather a high bluff above that lake. Turning off my headlights well before I reached them, I joined a hearty group of sky watchers who had staked out what they hoped would be a good spot to catch this stellar event. This is Martin. No, hi. Martin is my lab assistant. He's been working with me. He started two months ago. Also at SETI?

Right now what we are just trying to find out is what's the best integration time for the observation. So we want to make sure we can see the star with a good signal-to-noise so we ensure that we see the star when it disappear occulted by Pluto. We have 30 minutes to test the software to make sure it works and as soon we have done that we're ready in fact we just did the most difficult part which was to find the field of view, to have all the stuff working and it's it's it.

I'm so paranoid about tripping over a tripod. It's somewhere in here. It can't be that bright is it? I don't think so. That's a hot pixel right there. Oh go back. Is that it? There's that one. If you're going one two it goes past the asterism. Is that it? That double?

That's the double right there. Okay. So if we go past the line is that that Pluto? What's that? That tiny thing is that Pluto and that's the star it's going in front of? Yeah. That tiny thing right there? Pluto and that's the star it's going in front of? That tiny thing right there? It could be. I think that's it. I think the magnitude checks out. I think that's it. So go back again. So here's the line of stars right here.

Here's the pointer. It's just past this line of stars right here. I think that's it. I think that's the one. My name is Frank Marchis. I'm a senior researcher at the SETI Institute. And I'm also the chief scientific officer of Unistellar. Frank, it is a great pleasure to join you here on the mountain. It's been a while since we've talked to you on the show. Thank you for inviting me out tonight.

Thank you for coming. I mean, it's a nice night, no? It is a beautiful night, great scene, what beautiful sky. Yeah, you cannot see that because it's radio, but right now we can see the Milky Way. And it's, I mean, it's gorgeous. It's absolutely gorgeous, I guess. Best sky I've seen since my time a few years ago in the Atacama. And it's pretty dark, which is a good thing, right? Because you're going to be trying to pick out Pluto tonight. Yes. So tonight we are going to observe Pluto while he's occulting a star. So in fact, we're not going to see Pluto. We're going to see the small attenuation of light, like the

disappearance of a star, while Pluto is passing between us and this star. Why, for those who may not be aware, are occultations so important, so useful to astronomers? So occultation is so important, so useful to astronomers. Occultation has been used for years to derive the orbit of a body, because with an occultation you know precisely the position of this body. You can also derive the size of the body. Imagine you have multiple people observing the occultation simultaneously. You can get the size of an asteroid by simply looking at the timing of each of those chords, timing of when the star appears and disappears. And for some cases, like Pluto and Triton,

you can also detect the atmosphere, the signal of the atmosphere, during the occultation. We know now, of course, because New Horizons had not much problem detecting that atmosphere, although there isn't much of it there. Do you believe that with this occultation you'll be catching tonight, that you'll be able to get some more data about that wispy bit of atmosphere? Yeah, we know that Pluto has an atmosphere,

and we also know that Pluto has a very eccentric orbit, so Pluto is kind of cooling down, and also the orientation of the area of Pluto, which has, we think, the most activity, is basically entering into the shadow. So it's cooling down. So we think that the atmosphere, the density of the atmosphere will drop. Models have been showing that. Climatic model of Pluto. We're now reaching the point where we can predict the climate on Pluto, which is absolutely amazing. Isn't it? So we will be able, with this occultation, capable of confirming whether or not this condensation, this disappearance of the atmosphere of Pluto is really happening.

So you're trying to prove out this model? Yes, we try to prove out these models. And I mean, there is always multiple models, and we know that the interaction between the surface of Pluto and the atmosphere is very complex, so probably our models are extremely simple, so probably we're going to see something even more interesting than what we expected. So what we think is on the surface of Pluto, we have ice,

and this ice is not ice, water ice. It's mostly NH3, so it's something that vaporizes at lowest temperature. This ice is basically in the atmosphere of Pluto, it's the main element. We also know that Pluto has on the top of the atmosphere aesis. This aesis is basically a complex interaction between the top of the atmosphere of Pluto and the Sun and the magnetic field, if there is any. It's a very interesting world, in fact. A few years ago, people would have said, oh, Pluto is a very boring, probably, planet.

It's nothing there. It's rocky and icy. But in fact, now we discover that there is a lot of activity on this planet, and this activity is difficult to understand. So with Pluto Pluto we can basically push the ultimate limit and see how well we understand the climate of a planet how rare is an occultation of something like Pluto it's a pretty small body obviously that's an interesting part in fact between 2002 and 2006, we had a lot of occultation, like three per year, roughly, because Pluto was in the Milky Way.

The Milky Way is the area where you see the most stars, because that's the age of the galaxy, basically. Pluto is now drifting away from the Milky Way, so those occultations are getting rarer. They're rare because to see an occultation, you need to make sure that the magnitude of the star which is being occulted is higher than the magnitude of Pluto, so magnitude 13. So we are now in an area of the occultation world for which we think we're going to have one event like this every three years, roughly, in average. So that's why we're here tonight, and that's why there is multiple telescopes across the United States, Mexico, and in Canada as well, which are observing this event.

It reminds me of, and of course it shares a lot of similarity with the total solar eclipse that so many of us enjoyed last year. The tension here tonight, and there are several scopes here tonight and some other folks that we'll meet, is pretty palpable because you've only got a few moments to catch this. How long will the occultation actually last? So we are close to San Diego, so this occultation will last 93, 94 seconds. In some of the places like Baja California, it will last 120 seconds. And more interestingly, if a thousand from here, it will last for a long time,

but we also expect to see a central peak, an additional brightening during the event, an additional brightening of during the event because the star will be located exactly behind us and Pluto. This peak, this brightening, is extremely useful because it gives you a 3D information of the atmosphere of Pluto. It can give you information such as if the atmosphere is circular, if there is a difference of temperature in the atmosphere atmosphere is circular, if there is a difference of temperature in the atmosphere, which is insignificant, etc. So some people move all the way to Baja California to do this observation, and they will cross, they will pass above Houston and above New Orleans.

I've got to tell you my greatest fear tonight, and I'm moving very carefully about here in the dark, because I'm terrified that I'm going to bump someone's tripod. Tell me about the telescope that you have over here because this is a story in itself. So this is the prototype of the EVscope of the company called Unistella. So Unistella is a company that is trying to democratize astronomy, make an object, a telescope, a device that everybody will be able to use. Our idea is not to make an object which is simple to use but also an

object which is useful for science. So people feel compelled to do observations, to take the telescope, drive for one hour in some specific area of the planet to see beautifully the sky and enjoy the sky while doing observation for scientific purpose. Today we brought this telescope because we wanted to validate the fact that we can use this telescope to observe as well an occultation of Pluto. There are some very special features of this telescope. It has an image intensifying system? Yeah, it has a system that basically accumulates light in real time. So what you see in the eyepiece is basically like if you have the power

to accumulate light over minutes of observation. And you see in color as well. So that's the neat features. It's a powerful telescope, and you will see more with this telescope than you will see with a normal telescope. So, for example, when I use my telescope and I point at a nebula, and I know that that nebula is just rich with color, but I'm not going to see that with my naked eye. I mean, that's really a time exposure.

But with this telescope, because of this technology, you would catch some of that color in real time, so to speak? Yeah, you will see it in color. In fact, we're going to show you after the occultation of Pryton. If you stay a few minutes, I'm going to show you that you see nebulas in color. You can see the green from the oxygen, and you can see the red from the hydrogen emission. I wouldn't miss it.

Tell me about, and I'll talk to them in a moment, but the other folks over here from Oceanside Photo and Telescope, I know them pretty well because, you know, full disclosure, I got my telescope from them years ago. So we started a partnership with OPT. They provided this amazing large telescope, a C14. And Joanna from the Observatoire de Paris came here with an EMCCD camera,

which is this extremely powerful camera with very high quantum efficiency, capable of collecting photons, one per one, counting photons. And this partnership is great because Joanna came with this tiny camera, which is kind of expensive, and she knows how to use it. OPT provided the telescope.

They set it up in a few minutes. It's impressive. They know what they're doing, obviously. We are going to observe all together this event, them with this large telescope and the MCCD camera, and us with our small telescope for the general public. Listeners are probably tired of me talking about this, but I have to bring up again the miracle of the camera technology that is available now, even to amateur astronomers, at the level that we're looking at here.

Now, this is a pretty sophisticated 14-inch telescope like that, and a pretty sophisticated, a 14-inch telescope like that and a pretty sophisticated camera. But does it amaze you what people can do now with, I mean, stuff that equals work that was being done not too far from here on Palomar Mountain by the Hale telescope, that 200-inch monster that is still a beautiful instrument. I often say, mention to my students and my colleagues, now I have this tiny telescope, and with this telescope I can observe Pluto in my garden. And I do remember when I started my PhD in 1996,

people were asking one-meter-class telescope time to observe Pluto, to refine this orbit and so on. Now with my small telescope in my garden, I'm capable of observing Pluto. That shows that we, in 20 years, made a significant progress in detector technology, telescope technology as well. And that's because we're using more and more detectors. There are detectors in everything, in your phone, and those detectors in your phone are amazingly powerful and smart. So what we're doing here with this telescope is basically the same.

We're using a smart and powerful telescope that will be taking full advantage of the development of technology around us. It must only be something like 20 minutes now left before the occultation. Maybe even less. I'm going to let you... Maybe we're going to be happy, Maybe we're going to be happy, maybe we're going to be crying in 15 minutes. I hope. Keep the microphone on.

Well, clear skies and success, and I will leave you to your business. We'll talk again afterward. Thanks. Thank you. Thank you very much. I'm going to walk over to that 14-inch telescope over here where they are still working,

and they have this very sophisticated camera hooked up. Yeah, we just got aligned on Pluto here with our wider field camera, switched it over. We're getting everything calibrated. We've got about 15 or 16 minutes before the occultation occurs here. everything calibrated, we've got about 15 or 16 minutes before the occultation occurs here. So we wanted to make sure we were set up in plenty of time to be able to record data leading into it and exiting the occultation. My name is Chris Hendren. I'm the Director of Educational, Government, and Commercial Sales at OPT. Have you done this kind of thing before, the occultation of using a tiny object like Pluto, trying to catch that?

This is kind of a first for us. OPT is really interested, especially in my department, in the promotion of scientific research, both in the professional realm and pro-am collaborations. So this is really exciting for us to be able to promote real scientific research and be a part of this very historic event that doesn't happen very often. Something we talk about pretty frequently on Planetary Radio is citizen science and the ability of so-called amateur astronomers, of course, most of whom are amateur only in that they're not getting paid for what they do, staying up all night many times. I imagine that that has been good for business at OPT. That boundary between professional and amateur has really blurred with the quality of equipment that's available. Several employees at OPT have observatories that are, some of them are actually operated remotely from over 100 miles away. They have customers that will buy a setup

that's capable of taking either pretty pictures or tracking asteroid light curves or doing photometric measurements of stars. The range of equipment available to the amateurs has grown immensely over the last decade. We just had a conversation not long ago on the show, not too many weeks ago, with an amateur astronomer, a recipient of one of our Shoemaker NEO grants. With a telescope in Morocco, he lives

in Switzerland and only visits the telescope, I think, once every month or so, if I remember correctly. So even more extreme case than what you were talking about. We see that a lot. And that's the level of sophistication that allows people to do remote scientific research as well as advanced amateur astrophotography. How long have you been at this? I got into the hobby seriously in about 2003. Started shooting with film, actually, if you can believe it.

One of the last holdouts there. Got one of the first generation digital SLRs in 2004 got into CCD astrophotography in 2006 I actually have been with OPT since 2006 so with this year I've been there about 12 years and it's been amazing to watch the hobby grow and how the level of technology has allowed it to reach more people. My first CCD camera was a two megapixel camera from SBIG. I thought I had gotten such a deal getting it under $3,000 and that was amazing. Now we have consumer CMOS based cameras with cooled sensors with 16 megapixels below a thousand. So it's democratized astronomy a little bit as the technology has come out and filtered down,

and it's allowed more people to get into it and experience that wonder. More is law, and it comes to astronomy. Absolutely. So what's the status at the moment? I mean, we're getting very close to this occultation now, and what am I looking at here? You have the operator who's brought you this very special camera, I guess, who's sitting at a laptop. Yeah, Joanna here is working with the University of Paris. She's brought this EMCCD camera with her over from France.

We have Pluto centered in the field, roughly. She had to have a couple of alignment stars in there, so it's not exactly centered. Roughly, she had to have a couple of alignment stars in there, so it's not exactly centered. But we're entering all the data so that we can tag it with the GPS, because that's very important. You want to have both the timing of it entering the occultation and exiting the occultation timed with the GPS, so that way it becomes scientifically relevant. I'll actually bring Joanna into it right now. Please do. Hi, Joanna. Hi.

I'm Matt for the Planetary Society and Planetary Radio. Is this exciting? Nice to meet you. Yeah, it's very exciting. You're with the University of Paris, but you don't sound French. No, I'm not French. I'm Portuguese. How did you end up here tonight? You're a long way from home. So we have a project in France that is about this type of events, occultations. And Frank knows the head of the project. They talked so they could get me here as well with the camera.

And we have people from our projects all around the u.s all observing the occultation tonight everyone's observing the occultation right now because mine's already recording so i'm hopefully everyone else is already recording as well i'm a phd student So I'm a PhD student, and if all goes well, I'll use this data in my PhD as well. And we have just barely visible there. I don't know if that's a helicopter or a plane, but it's pretty big. It looks like it's two things. Oh, you're right.

Probably the military. Okay. Well, fortunately, they're not shining any search lights over this way. You are here and your colleagues from the University of Paris are all here just for this event tonight. Yes. All right. Well, I'm going to stay out of the way because as I told Frank, my greatest fear is that I will bump someone's tripod. So I'll stay well back and let you do your work and keep the microphone out so we can catch some of the excitement thanks very much for talking with me

you're welcome, thank you can you point out Pluto there? well the star that it was in is just up the bright star that's just left of center right there that star just dimmed for about 94 seconds it got significantly dimmer

and then it just started brightening again as it came out of occultation. It happened. It happened. Yep. Yep. We were pointed at it. We watched it.

Well done. Congratulations. I'm glad you didn't come here for nothing. Thank you very much. Absolutely. Congratulations, everyone. First collaboration. We need to do that more often. We need to. I'm sorry. We did it, man. We did it. We did it. Absolutely. Congratulations everyone. First collaboration, we need to do that more often.

We need to, yeah. We did it, congratulations. Oh man. Congrats. You have no idea how difficult this can be. And sometimes, Thank you. Congratulations.

Oh thank you, this has been awesome. Oh man, that was awesome. Mac and Brie, thank you. Congrats. Congrats dude. Oh, we're done. That was awesome, congrats man. I have a video of it, yeah. It worked through your scope as well?

We don't, we're still saving data, so we're going to see that in a few minutes. Okay. But one of them worked for sure, so that's good. So what happens now? You will take this data, the light curve, this dip in brightness of that star, and take it back and analyze it? Yes, so Joanna is basically going to work as a PhD to collect all the light curves and put them together and write a model of the atmosphere of Pluto based on these observations.

Because we have different sampling, we are going to be able to have different information depending on the telescopes, of course. This one is going to probably give us a lot of information about the atmosphere, the density. Some people observe using near-infrared, so we have some information about the composition as well. In our case, it's mostly about the timing and the size of Pluto as well. That's going to be useful.

I'm a bit... Sorry, I hope I make sense. No no no it makes perfect sense. The number of times we try occultation and it doesn't work. It can be anything from the battery dying, from the disk not saving, from the wind, from the weather, from the car not working, from Windows deciding to make an update at this moment. I mean you have a lot of stuff like this that can happen. So it's always great feeling to see that suddenly everything worked. It's been a good night. Yeah, it's been a good night. Definitely. Time for What's Up on Planetary Radio.

Bruce Betts, he's the chief scientist for the Planetary Society, does a lot of other things, including joining me each week for this segment, beginning with his description of the night sky, which is still pretty good, isn't it? Hi. Hi, Matt. Yeah, I'm repetitive, but it just doesn't happen that often that we get to party with four planets in the evening sky. So darn it, go party with four planets in the evening sky. That means you, Matt. So soon after sunset, look to the west and you will see super bright

Venus. Then rotate and in the southwest, you'll see Jupiter looking very bright. Farther around towards the east is Saturn looking yellowish. And then Mars still looking quite lovely and bright after, let's see, we're about three weeks after closest approach. But still awesome and fading. So, hey, enjoy it now. We move on to this week in space history. Enjoy it now. We move on to this week in space history. 2003, 15th anniversary of the launch of the Spitzer Space Telescope.

Despite being planned for an initial period of two and a half years with some extension possible, they've actually figured out, even after they ran out of liquid helium, how to keep doing all sorts of great stuff with the shorter wavelength infrared bands they've got. So happy 15th anniversary, Spitzer Space Telescope. They really know how to build that stuff. They do indeed. They keep me away from it. It's rule number one. All right.

We move on to random space fact. It's something. I can't place it, but I know that from somewhere. Deep within the recesses of the unused neurons of my brain. That's what it is. Now, it'll come to me probably a couple of minutes after we've finished. Anyway, go ahead. All right, you let me know.

Speaking of Spitzer Space Telescope, it's got an 85 centimeter primary mirror made out of beryllium, or at least the structure is made out of beryllium. Beryllium, same material, same element that the JWST's mirrors are made of, I think I remember. I believe you are correct. I believe you are correct. And not coincidental, they're both working in the infrared, different parts of it, and probably using gold as the reflecting material. But I'm going out on a limb. I don't remember for Spitzer. Such a nice infrared reflector.

We're ready for the contest. We go, as always, to music. We go, as always, to music. I asked you, what singer-songwriter referred to an experience watching the Per, and in that was this line. And like our winner this week, Claude Plymate, who said, I had no idea that is what John Denver was referring to in Rocky Mountain High. How cool. He said he always assumed the line was describing a lightning storm, and he's going to take a fresh listen. Claude Plymate, John Denver, you don't have to tell us. I know it's correct. Claude is our friend who's been a guest on the show a long time, listener, first time winner. He is an astronomer at the Big Bear Solar Observatory that we featured a few months back on this very program.

Congratulations, Claude. Congratulations. He got himself a Planetary Radio t-shirt, which will look great up there in the observatory, a 200-point itelescope.net astronomy account, and the first of those two codes, download codes for Distant Suns VR, Distant Suns Virtual Reality. The terrific astronomy program's been around forever, the work of one wonderful guy, and he's just come out with the virtual reality version. It's only for iOS,

so sorry about that, Android people, but Claude's going to get to play with it, and he'll have nice guys to try it out with up there in Big Bear. Very cool. We got some great responses from other people as well. Mark Smith, my countryman here in San Diego, he says, John Denver, of course, he was 27

the year he saw that shower. He had just moved to Aspen. The first words of the song that came to him were actually, the shadow from the starlight, which is a great line. Mark would like more song poetry quotes to research, please. All right, I will take that under consideration. I've used it only very occasionally in the trivia questions. Robert Klain wants to ruin some of your other opportunities to do this. He says, however, both the Nitty Gritty Dirt Band and Ozzy Osbourne, rock and roll, have songs with fire in the sky lyrics. And then he adds, I never thought I'd be using Ozzy Osbourne and the Planetary Society in the same sentence. Why not? It just seems obvious to

me. Just listen to us. We're definitely on a crazy train. David Fisher, Deep Purple had fire in the sky with smoke in the water, but that's another story. Dinosaurs had a fire in the sky, but they forgot to write about it. You know, one of the few times I've used song lyrics was Deep Purple for their lyrics from Space Truckin'. I remember that. That was a random space fact, random fact. That was a random space fact, random fact. Adam Kajokar. Interestingly, Denver, and this is true, I checked it out, was born in Roswell, New Mexico, four years before the famous incident there. What if he wasn't referring to the Perseid shower, but a UFO streaking across the sky?

A parentheses, a just tinfoil hat. Finally, from Jake Spear in Sydney, I wonder if John's song Calypso is actually about the Saturnian moon. He says, though I'm a big fan of John Denver, I'm an even bigger fan of Planetary Radio and all that the Planetary Society does. Always love tuning in every week here, Down Under. That's it. That's the select few that made the cut this week. Thank you to everybody who entered and sent us fun stuff. Yes, thank you. Thank you all. And here's a new question for you.

Sorry, there are no song lyrics that I'm aware of involved. Who was the Spitzer Space Telescope named after? And don't just say someone named Spitzer. I need at least a first name with this. Who was the Spitzer Space Telescope named after? Go to planetary.org slash radio contest. This should make some of you very happy. The ones who are looking for another easy one here.

Shouldn't be too difficult, right? You have until the 29th. That'll be Wednesday, August 29, at 8 a.m. Pacific time to get us the answer. And somebody out there, someone is going to win a Planetary Radio t-shirt. You can have a look at it at chopshopstore.com, where the Planetary Society store is,

and a 200-point itelescope.net account, which is that worldwide network of telescopes has a brand-point itelescope.net account, which is that a worldwide network of telescopes has a brand-new wonderful tool for using those telescopes. It makes it easier than ever to take a look around the sky. And that's it. We've had our look. All right, everybody, go out there, look up at the night sky, and think about if a cubicle had a circular cross-section, would it be called a spherical?

Thank you, and good night. You haven't touched the pie in my spherical, have you? That's Bruce Betts. He's the chief scientist of the Planetary Society. He joins us every week for What's Up. Planetary Radio is produced by the Planetary Society in Pasadena, California and is made possible by its Pluto-loving members. Mary Liz Bender is our associate producer. Josh Doyle composed our theme, which was arranged and

performed by Peter Schlosser. I'm Matt Kaplan at Astra.