Planetary Radio • Jun 16, 2021
Amateur Astronomers Saving the World
On This Episode
Russell Durkee
Astronomer and high school science teacher for The Shed of Science Observatory
Alessandro Nastasi
Astronomer for GAL Hassin International Center for Astronomical Sciences
Rae Paoletta
Director of Content & Engagement for The Planetary Society
Casey Dreier
Chief of Space Policy for The Planetary Society
Bruce Betts
Chief Scientist / LightSail Program Manager for The Planetary Society
The Planetary Society has awarded more than 60 Shoemaker near-Earth object grants to astronomers around the world, enabling them to discover, track, and characterize thousands of asteroids. We’ll hear from two of these dedicated observers. The Society’s Rae Paoletta takes us to Venus where three new spacecraft will help answer big questions. Senior space policy adviser Casey Dreier helps us think about UFO claims. Chief scientist Bruce Betts offers a new What’s Up space trivia contest.
Video tour of GAL Hassin International Center for Astronomical Sciences in Italy Alessandro Nastasi provides a tour of the GAL Hassin International Center for Astronomical Sciences in Italy. Nastasi and his colleagues received a Planetary Society Shoemaker NEO grant in 2019 to install a new dome and timekeeping system that improved their ability to observe potentially dangerous near-Earth objects.
Related Links
- Shoemaker Near-Earth Object Grants
- Announcing the 2019 Shoemaker NEO Grant Winners
- GAL Hassin Astronomical Observatory
- Double Venus missions: all the burning questions NASA hopes to answer
- Is it aliens? Three questions to evaluate UFO claims
- The Downlink
Trivia Contest
This week's prize:
A hardcover copy of Carbon: One Atom’s Odyssey by John Barnett
This week's question:
After the Sun, what star has the largest angular diameter as seen from Earth?
To submit your answer:
Complete the contest entry form at https://www.planetary.org/radiocontest or write to us at [email protected] no later than Wednesday, June 23 at 8am Pacific Time. Be sure to include your name and mailing address.
Last week's question:
Who holds the record for most launches from Earth (and only Earth) at seven?
Winner:
The winner will be revealed next week.
Question from the June 2, 2021 space trivia contest:
As of June 2021, how many of the nine spacecraft that have visited Jupiter are still communicating with Earth?
Answer:
As of June 2021, four of nine spacecraft that have visited Jupiter are still communicating with Earth: Voyagers 1 and 2, New Horizons, and Juno
Transcript
Mat Kaplan:
Saving the world one asteroid at a time this week on Planetary Radio. Welcome. I'm Mat Kaplan of the Planetary Society. With more of the human adventure across our solar system and beyond, Russ Durkee lives in Minnesota. His astronomical colleague, Alessandro Nastasi, is more than 8,000 kilometers or 5,000 miles away in Sicily, but that separation can't compare to the distance to the objects they study. These amateur astronomers spend nearly every clear night, watching the skies for space rocks that cross our planet's path. They'll tell us about their work. We'll also welcome my colleague Rae Paoletta in a couple of minutes. Rae has written an article reviewing the big questions we have about Venus and the spacecraft that may provide answers. UFOs are back in the headlines, even if the US government now prefers to call them unexplained aerial phenomena or UAPs. Planetary Society Senior Space Policy Advisor, Casey Dreier, will share his thoughts about how to evaluate what Carl Sagan called extraordinary claims. A special welcome this week to Science Rules! listeners, our boss at the society, Bill Nye asked us to fill in while he's way.
Mat Kaplan:
In case you're new to Planetary Radio, we've been talking about space exploration every week for well over 18 years. You can check out our more than 1000 episodes at planetary.org/radio or wherever you get your podcasts. We've always got a lot going on at the Planetary Society, including our free weekly newsletter called the Downlink. Here are few headlines from the most recent edition.
Mat Kaplan:
It's taught by a spectacular image of the eerie overheated Venusian surface. Just below is a shot of Jupiter's moon Ganymede, grab barely a week ago by the Juno orbiter. We haven't seen pictures like this of our solar system's biggest moon since the Galileo mission more than two decades ago. You've probably heard by now that Jeff Bezos and his brother will be onboard his Blue Origin New Shepard when it makes its first crewed suborbital flight. We know yet know the identity of the person in the third seat, but we do know that she or he paid $28 million for the ride. And that's not including the 6% buyer's commission. No word yet regarding carry-on bag fees for the 11 minute flight. Want more? You'll find it at planetary.org/downlink. The long Venusian drought is over. Here's Planetary Society editor, Rae Paoletta. Rae, welcome back. And thank you for this June 9th article, Double Venus missions: all the burning questions NASA hopes to answer. No pun intended, I'm sure. Double, it's now triple, right? Tell us about this new announcement from the European Space Agency.
Rae Paoletta:
Yeah. So we're actually getting not one, not two, but three missions to Venus, which is going to be super exciting. The third mission is actually called EnVision. ESA just announced recently that they're going to be sending their own spacecraft to Venus, which is just incredible. I mean, it's been 30 years since NASA has sent a spacecraft to Venus. The last one I believe was Magellan. So it's wild that everything is just turning up Venus.
Mat Kaplan:
Yeah. It's about time. 31 years since that launch of Magellan. It's just absolutely crazy that we've had to wait this long. We hope to have the principal investigators for both of the NASA missions on pretty soon. Maybe we can get the EnVision equivalent of a PI as well. There are a lot of questions that we hope that these missions are going to help us to answer, even if they don't provide full answers. You cover a lot of them in this article. One of them, we go back to that drought I mentioned at the top of this segment, water. There's all this speculation about did Venus, was it a much wetter place billions of years ago like Mars? Is this going to help us with that?
Rae Paoletta:
Yeah, it's really incredible. I mean, when you think of something like Venus, it's hard to imagine that there was anything ever even just resembling an ocean on the planet, but there's actually a good chance that, hey, there might have been a watery past. So I think that with DAVINCI+, the space craft is actually going to drop a sphere through Venus's atmosphere and measure some of those noble gases that could be there. And that seems to be a big clue in finding out whether or not Venus ever had an ocean. Everything with these Venus questions is interrelated, an ocean, plate tectonics, volcanoes. So I think that DAVINCI and VERITAS together, which is the other NASA mission, they're going to tell us so much about whether or not there was ever an ocean on Venus, or maybe, hey, is there still water on the planet? One idea is that the Venus might have volcanoes that are spewing water out. So I guess we'll get a look into that as well.
Mat Kaplan:
Just crazy. Wouldn't that be? I mean, cryovolcanos in the outer solar system and water volcanoes on Venus. Very quickly, are these missions going to be able to help us with the great phosphine debate and the question about whether, not just past life, but maybe current life in the atmosphere above the world?
Rae Paoletta:
Oh yeah, it's incredible. I mean, it seems like DAVINCI+ in particular is going to maybe be able to offer us just some clarity here when it goes through Venus's atmosphere like I said before, but both DAVINCI+ and VERITAS, it seems are going to scope this out for us in different ways. It's just so cool to see it, hey, are we going to get some new answers in this possible phosphine detection debate? What does that mean? Does that mean that Venus has clouds or maybe hiding some form of life? Obviously, that would be one of the biggest discoveries in the history of anything ever, but I think that it will be a good start to just see if Venus was ever once habitable.
Mat Kaplan:
And we have a good start. Sadly, it's going to be more than 10 years before these spacecraft reach their destination, second rock. But that is going to be a very exciting occurrence when they all go into orbit around Venus. Rae, thank you very much for joining me once again.
Rae Paoletta:
Always a pleasure, Mat. Thanks so much for having me.
Mat Kaplan:
And I'm going to recommend her article once again, you'll find it at planetary.org about the two NASA Venus missions. I bet we'll have something to say about the European Space Agency mission, EnVision, before too long as well. Rae is one of my esteem colleagues at the Planetary Society. And we're going to go now to another of those colleagues who you hear from pretty regularly, especially on the Space Policy Edition. That's Casey Dreier, who has put together a piece that you can also find at planetary.org about the possibility of aliens.
Mat Kaplan:
Casey great piece also published on June 9th at planetary.org titled, Is It Aliens? Three Questions to Evaluate UFO claims. This is not an article to read to learn a lot about the current stuff that's going on with those sightings by Navy pilots and the report that's coming out. For that, I highly recommend taking a look at this article by our friend Leonard David, the guy I call the dean of space journalists, which we will provide a link to from this week's episode page at planetary.org/radio. Leonard has done a really good job capturing that story. Casey, it looks like you really want people to think about how to think about extraordinary claims like these.
Casey Dreier:
Yeah, there's always going to be some UFO sighting that you can find specific debunkings of pretty readily, but I think the bigger skill to have, particularly for this age where information is free to distribute, so there's going to be a lot of it out there, it's just to be aware of how people present information to you and just basic gut check questions to ask yourself when presented with pretty incredible claims. This article that I contributed to and was a group effort by me and Rae and others here at the society, it was just presents three basic questions to start thinking about when you see these types of big claims that you may want to believe it, right? Particularly this is true for things we want to be the case.
Mat Kaplan:
Yeah. I want to believe.
Casey Dreier:
Yeah. There you go.
Mat Kaplan:
This first one, I'll read it. Does the UFO sighting violate our understanding of physics?
Casey Dreier:
We know physics pretty well. And even the areas in which we don't understand the details of physics, they're areas of extremes, like the insides of black holes, the very beginnings of the universe or the micro, micro, micro microscopic quantum world. Beyond that, in terms of how we understand physics to be things like conservation of mass, conservation of energy, particularly basic ones, they're so well established that yes, there is maybe a fractional possibility they are wrong or need refinement, but the claim to overturn those would be almost bigger than the discovery of UFOs themselves that they were violating the conservation of energy, right? That's how fundamental they are, that's how well established they are.
Casey Dreier:
This is one of the valuable things I've felt I've had. And that's why I always encourage people to take at least some college level physics, regardless of what your future is going to be, because it really helps to have kind of a BS detector about what is established understandings of the physical world in which we exist versus what would be in a really outlandish claim against them. And understanding how the physical world is established and understood to work, then you understand, again, that to say some of these things appear to be moving faster than the speed of light or would create sonic booms based on how fast they would move, you start saying like, is this consistent with what we understand about the natural world?
Casey Dreier:
And if it's not consistent, then you have to tune your dial of probability of being correct down a little bit, because then it's not just asking you to believe that some intelligent life has come all the way over to earth to visit us and not really want to be shown, but just a little bit in blurred videos, or that plus that they seem to violate well-established laws of physics. So that's an even bigger claim where that's a bolder claim that really, really, really then needs a lot more evidence behind it.
Mat Kaplan:
Extraordinary claims require extraordinary evidence said our founder. Here's question number two, does it require a large conspiracy involving aliens because the federal government is so good at keeping secrets?
Casey Dreier:
I've done policy now for a decade and I've been to government, I've met people who work at government. And for the most part, they're just dedicated public servants, pulling in a middle-class income who put up with a lot of crap, but also really dedicated to what they do. Do you require this large conspiracy to hide this, to not tell the truth? I mean, look at Edward Snowden with how much information he released about actual national security issues that tend to be secret, but for very good reason or at least understood by those who participate in that system. It's very easy for things to leak and particularly over time as people age out or get newly involved in it, like the more people you have in a conspiracy, the more likely it is someone's going to blab or record something or find some giveaway.
Casey Dreier:
The amount of effort it would take to maintain a perfect conspiracy for an epical discovery, such as intelligent life visiting us that no one wants us to know, again, that's where you say, okay, you're not just making a claim about aliens, you're making this really audacious claim about massive conspiratorial work by, not just our government, but governments around the world that usually seem to have no interest in collaborating with each other anyway.
Mat Kaplan:
So the third question, and perhaps my favorite, because it has long been my favorite, is there a simpler explanation? And you start right out with Ockham's razor.
Casey Dreier:
Always a good go-to. And I even like to think of this in my physics background as an equivalent of like entropy, right? Entropy is the state of disorder. There are more ways to have dishes in your kitchen spread around the kitchen than there are ways that they would be perfectly packed in your cupboards. And so it's just more likely that your dishes are just going to be spread around. Is it an alien flying around that requires all of these things to be true? Or is there more ways than which uncertain signals can be interpreted incorrectly? High-speed aircraft, weird optical aberrations from highly advanced sensors, image processing, things that you're just not familiar with.
Casey Dreier:
The number of ways in which that information, those photons are collected, processed, interpreted, and then shared with you is so great. There's so many simple explanations along that pathway that can probably give you the same sort of ambiguous signal. We've seen a lot of great, he said Leonard David's article, Nick West on YouTube has been doing a lot of really important and providing a lot of very reasonable interpretations of these data. And most people just don't use those things. We're just not familiar with them. And so we can be tricked all the time.
Mat Kaplan:
Casey, I don't know about you, but I know a lot of planetary scientists. I think every single one of them would be so thrilled to find real, reliable evidence of life elsewhere, anywhere in the universe, especially intelligent life that I think they'd be the first one to talk about it.
Casey Dreier:
Yeah. I mean, there's that too. Scientists and people who dedicate themselves to this, many of them cite that wonder of the idea of not being alone in the universe as their motivation for why they got into these fields. This is why we do missions like Perseverance, this is why we're making missions like Europa Clipper, because these are actual ways to systematically interrogate the question of life beyond earth and not just passively wait for weird blobs to be revealed to us, but to actively seek out in situ or via photons or whatever, I'd say people at SETI are doing the same thing, to actively seek out these answers. And we have the technology to seriously do this.
Casey Dreier:
That's what I think is so sometimes frustrating for us in the community because we have these real commitments to, as you know, here at the Planetary Society, one of our core enterprises is finding life beyond earth if it's out there. So I'd love nothing more than to see this. This is I think what that frustration comes from because actual evidence for, the active positive evidence for these being anything but unidentified blobs, there's so little active evidence for that. Yet it captures so much of the discussion right now, taking away from what we're actually doing. That can be frustrating. The excitement is valid. Let's channel that energy into these areas where we're actively seeking out answers to these questions.
Mat Kaplan:
So much real science going on throughout the solar system and beyond for us to get excited about. Casey, we're not quite done with this topic because you will have a special guest in the July Space Policy Edition. Do you want to tease that a little bit?
Casey Dreier:
Yeah. We'll have Sarah Scoles who wrote, They Are Already Here, a book looking into the culture of folks who seek out and try to understand themselves UFO sightings. And also, she's done a lot of great work, very familiar with the type of people making these big claims right now. And she'll help us shed a little more of a cultural context and insight into these specific issues that are going out right now. But also again, we'll talk more about these ways to approach big claims like this, how we can use our good reasoning skills to interpret and assess the feasibility of some of these wild claims that are going about. And I think those are just good skills to work on and be aware of for anything, not just this issue.
Mat Kaplan:
Watch for that episode of the Space Policy Edition if all goes well Friday, July 2nd, first a Friday in July, where you catch Planetary Radio. Casey, thank you as always.
Casey Dreier:
Always happy to be here, Mat.
Mat Kaplan:
Casey Dreier is the Senior Space Policy Advisor and Chief Advocate for the Planetary Society. Astronomer and planetary scientists, Bruce Betts, is the Planetary Society's Chief Scientist. Just one of his duties is management of the Shoemaker Near Earth Object grant program. Of course, he's also the only other person heard on every episode of Planetary Radio since our premiere in 2002. Bruce, we get to talk to you up front once again, of course, we're going to be back with what's up toward the end of this week show and a contest in which we will be awarding a really terrific, just gorgeous book called Carbon: One Atom's Odyssey. Anyway, more about that later in the show. As you know, I talked with two of your Shoemaker NEO winners, Russ Durkee and Alessandro Nastasi. We're going to hear from them in moments, but there were a lot of other folks who were awarded grants about a year and a half ago.
Bruce Betts:
There were. There were six grant winners at that time, but we've given 62 grants over the 20 plus years of the program for a half million dollars. So there are a lot of grant winners being represented by those two. Shoemaker NEO grants, Near-Earth Object grants fund really advanced amateurs as well as professionals to upgrade their observatory facilities to mostly do tracking and characterizing of near-Earth object to save the world.
Mat Kaplan:
Has it been as successful as anybody hoped? I mean, neither of us was around when this got started, I guess. Were we?
Bruce Betts:
But we were alive. And you may or may not have been, I was not, in '97. It was started after the passing of Gene Shoemaker, the planetary scientist who did so much to teach us about the importance of impact in the solar system and impact on earth. It's been more successful by far than I think anyone ever could have hoped because it really fills a niche for this group that doesn't have obvious sources of funding and they're able to take their observatories to the next level, whether it's, well, you'll hear about what these two have done, everything from cameras to real luminizing mirrors, to automating things so that observatories can act robotically. So it's really, I mean, we have professionals telling us all the time how significant the impact of these amateurs and professionals that get Shoemaker NEO grants have been.
Mat Kaplan:
So we got a US Midwesterner and a fellow in Sicily under the boot of Italy. They really have come from all over the world, haven't they?
Bruce Betts:
We have awarded to, I believe, 19 countries and six continents. Antarctica, we're looking to you.
Mat Kaplan:
Accepting newer Shoemaker NEO proposals right now, huh?
Bruce Betts:
Yep. We've got a call for proposals out. You can go to planetary.org/neogrants, N-E-O grants, and learn more. But the deadline is July 28th of 2021. And if you've got an observatory and doing serious work involving near-Earth asteroids and looking for some help to upgrade your equipment, think about submitting a proposal.
Mat Kaplan:
I don't know if there's anything else that we need to say upfront. We probably ought to hear from these two guys who have seen such benefits in their search, also characterization of near-Earth objects. But Bruce, as I said, we'll be back with you in a few minutes after we've heard from them. Thanks for joining me up front.
Bruce Betts:
Most excellent. They're doing great work.
Mat Kaplan:
The first of the Shoemaker NEO Grant recipients we'll talk with today received his third grant in late 2019. I called on Russell Durkee a few days ago for this report on his work and about the opportunities it has provided for some of his high school students in Minnesota. Russ, welcome back to Planetary Radio a year and a half after our first conversation. When you had just been awarded that Shoemaker NEO Grant, your third. So you are a multiple recipient. Welcome back to the show.
Russ Durkee:
Thank you, Mat. Great to be back.
Mat Kaplan:
Shed of Science. I love it, but how did it get that name?
Russ Durkee:
Well, I have to thank Bill Nye actually.
Mat Kaplan:
Really?
Russ Durkee:
Yeah, because I remember in college, I was in college when Bill Nye was doing his show on television and we'd watch it every Saturday morning. I remember he had a bucket of science at some point in one of his shows and I just thought that was awesome. And so when I was looking for observatory names, it was just a shed in my backyard. And so I said, well, this will now be the Shed of Science. And had I actually thought about it and knew that I would be still using it and trying to get grants and things like that using the name, I probably would've picked something a little more distinguished, but Shed of Science is worked out just fine. And that's where it came from to be honest.
Mat Kaplan:
I love it. I know that the second of these three grants was also to allow you to buy a camera. We talked about that last time. And then something like 10 years passed and you picked up the camera that this current grant was able to get for you. How's it working out? Is it proving to be as valuable as you hoped?
Russ Durkee:
Yeah, so far, so good. It started off a little rough. These cameras aren't things you can buy off the shelf, you order them from specialty manufacturers and they make them to order and it arrived about six months after I made the purchase. And yeah, it's amazing the lead time. Then I installed it a month or two later, since my observatory is across the country for me. Then it proceeded to fail right after I drove across the country. And it took a month or so that the manufacturer was wonderful to work with. They fixed the camera, sent it back and I had a colleague install it for me. And it was off to the races. So it took, I made the order probably in November or December, I received it in March. It went back for repairs and I didn't have it operational until September, I think. So it was a little rough start, but since then it's worked beautifully. And in fact, I ran it last night. And I'm looking at data as we speak.
Mat Kaplan:
So nine or 10 months now where it's been working pretty reliably. What kind of improvement has it made for you? I mean, how dim an object could you really observe in the past and what's the level now, the magnitude?
Russ Durkee:
I typically observe objects that are around 15th magnitude or so, sometimes they're brighter, 14th magnitude is a little unusual. Before this, I was maybe observing objects down to 16th magnitude reliably with sufficient signal, but now I'm routinely going at least a magnitude and a half deeper. I've observed objects 17 and a half magnitude. And it allows me to operate at much cooler temperatures because the electronics are much more sensitive, the cooler they operate. And so cooling is a big deal. And in Texas where the observatory is located, it's not unusual for the temperature to be 90 degrees at sunset and 80 degrees at sunrise, or maybe even warmer at times. So that cooling is really important. And this camera is fantastic at it.
Russ Durkee:
The other amazing thing that has happened is that the camera that I did have didn't go by the wayside. I was able to sell that to a colleague who is doing photometry as well. And so he's continuing to use that camera and he uses it for variable star work. That's happened more than once in this whole process back in 2009, or it was 2010, I believe, the camera that I replaced, I sold it to Gary Hug, I think. And he was a Planetary Society NEO Grant winner and he needed an extra camera. And so all of the people who do this kind of science work on the side, the money doesn't disappear forever. We make sure we take care of each other. And I know even Robert Holmes who was a long time a Planetary Society Grant winner, I bought a camera from him that he had after he got a NEO Grant. So it pays dividends for many, many years. And that's one thing that I really appreciate about these grants. It's an amazing benefit for us. We're really doing this research out of pocket for decades and decades.
Mat Kaplan:
I love hearing this. I had no idea that the benefits of these grants were rippling out across the astronomical community. It's delightfully incestuous, if you would.
Russ Durkee:
It is. It's great. It's fantastic. And since we're all connected, we just shoot emails off to each other, we collaborate like crazy. Don Pray and I collaborate all the time and he's a multiple NEO Grant winner. It's a really great community of people.
Mat Kaplan:
For the non-astronomers out there, 16th, 17th magnitude, we're talking really dim objects here. And when you talked about a magnitude and a half improvement over your previous camera, that may not sound like much to people, but it really is, isn't it?
Russ Durkee:
It's a remarkable difference. Your eye can see down to maybe fifth, sixth, seventh magnitude if you're lucky and you have a dark site. It's remarkable one magnitude, it's enormous really. And the thing is a lot of these objects, we're studying more and more of these objects and the Planetary Society has been investing money in telescopes that are a little larger, telescopes that are in better sites over the years. So you really need to continually update your equipment in order to keep up with the cutting edge research, just like anything else, it's getting more difficult to do good work. And so you need the best equipment out there.
Mat Kaplan:
Yeah. I mean, the objects as we find the bigger ones, they're just getting smaller, right? And a lot of them are really dark.
Russ Durkee:
Yeah. They're dark. I mean, they can be like a piece of coal or it's, we see the moon in the sky lit up all the time and we don't realize it's only reflecting a tiny percentage of the light that actually shines on it and it's dark as coal dust. In the end, these asteroids can be very much the same. And you have to remember, they're really far away. They're out in the asteroid belt sometimes and somewhere in between. And they're tiny. They're only tens of kilometers across a lot of the time. And they're quite tricky to follow.
Mat Kaplan:
Yeah, of course. Tiny is relative, because if one of those that is tens of kilometers across comes across our planet, that's going to make a pretty big dent in our world. Tell me, where are you sitting right now?
Russ Durkee:
I'm sitting in my basement one day after ending the school year. I'm a high school science teacher by trade. This is my first day of summer vacation. And I can tell you, it never gets old, you still get that little thrill at the end of the school year.
Mat Kaplan:
I'm married to an eco former teacher, retired teacher, I know how she felt about it. Congratulations.
Russ Durkee:
Thank you.
Mat Kaplan:
You're in the Minneapolis–Saint Paul area, you said your observatory is in Texas, not the most convenient arrangement. And in fact, your observatory used to be much closer to home, but you eventually hit the time when you had to move it, right?
Russ Durkee:
Yeah, that's right. I was operating sort of a little secret out of my backyard in Minneapolis for years. And it's not an ideal place to have observatory, but you can make it work to a degree. And I did it just to see if it could be done. And then I started studying, doing photometry of asteroids, which is measuring the brightness of asteroids, as opposed to measuring the positions. I'm measuring the brightness changes with these things. And so you can see the brightness change as the object rotates. And so it gets bright as you see the broad side of the object and dimmer as you see the narrower side. And I found I could do this, even though I was in the City of Minneapolis. And eventually had to start using a light pollution filter, but I was still able to get very high quality photometry.
Russ Durkee:
But over time, the object started getting dimmer that I needed to study. And the site just was not as useful anymore. So I had to make that big leap to set up a remote observatory. So with a lot of expense and a lot of careful planning, I found excellent site in Texas where there's a number of observatory setup. We connect them remotely. So I connect from my basement. I have a VPN connection and fiber optic internet on both ends. And it's just like being there. It's an amazing thing. And if you would've told me 20 years ago when I set up my telescope in the backyard that I would be doing this, I would have been shocked to be honest. But here we are.
Mat Kaplan:
I know you still have to head down to Texas periodically, although it sounds like you've got some colleagues down there who are able to take care of some things for you.
Russ Durkee:
Yeah, that's right. It's a remote observatory and it's robotic, but I wouldn't call it autonomous. These things need to have somebody nearby to really help you with those situations that are unexpected. If a breaker goes off unexpectedly, you sometimes have to have someone go in there and help you if your telescope gets hopelessly lost and it collides with something, which sometimes happens. I had a telescope that didn't park itself one night and it proceeded just do what telescopes do. And it followed the sky all night long. And 12 hours later, the telescope was upside down and it had pushed the camera, pushed the computer aside very gently and jam the focuser. And these sorts of things happen. And so you need to have very good friends that can help you out of those situations, because that is a long drive, is a couple of day drive or an airplane flight.
Russ Durkee:
For the most part, though, you can, if you design things carefully and you do this right, they'll operate for six months or a year at a time with a little bit of luck. You don't need to go down and do it that often. But I schedule a trip probably every four months to six months. I'm thinking about going down there in August again, and just to do some housekeeping and optics cleaning and different things that need to be done.
Mat Kaplan:
Well, safe travels as you do that. This is, people wonder why at JPL and places like that, APL, puts so much work into the reliability of the spacecraft that they send out. Well, it's because we haven't found any friendly Martian colleagues yet to go kickstart or reboot a rover if it has trouble on Mars. Congratulations again on completing the school year, but I know that a big part of what you do has been involving students. You've been using your tracking of NEOs your idea, your characterization of NEOs, to help in your teaching, because after all, you're a science teacher, you're still doing that. And how has that worked out during this awful year, a little more than a year that we are hopefully coming to the end of?
Russ Durkee:
Yeah, this was the toughest year I've ever had as a teacher. It started off online. And so we had a contingent of students eventually that were at school and some kids that were online. And I was online most of the year myself due to some health issues. It was extraordinarily difficult to teach science, which is really best done with labs and hands-on experiences in addition to the mathematics that you might have. And so it was hard on everybody, but especially the kids. We made it through. I've lost track of how many different schedules we've had and how many different groups of kids that were online at any given time, but we managed to get through it.
Russ Durkee:
I'm also lucky enough to teach an astronomy class. And in that class, we did a few virtual star parties, which was fun with the observatory. Kids were able to log on and see the telescope operating in real time. That inspired a couple of kids to try to do some work with me this year, but this wasn't the perfect year to do that. However, we do regularly have students that I work with on these projects. And I've had in the last couple of years, we've had students that followed near-Earth asteroids, I've had students that tried to identify binary asteroids, and I was lucky enough to have a student even go to the International Science Fair as a result of working with the observatory. And so I'm ready to do that again next year. So it's a great opportunity for kids.
Mat Kaplan:
I'm glad you mentioned binaries, binary asteroids, double asteroid, because that I know has been a specialty of yours, a particular area of success. Why are they so useful in the kind of work that you do? And that's photometry, which I guess you should also define for us.
Russ Durkee:
Yeah. So photometry is essentially just measuring the brightness of the object. And it's harder than you might think it would be to be honest, because you're just measuring light falling down on a sensor, but how do you compare it to something else in order to get it to real brightness is the problem. And so you generally compare them to other stars that happen to be in the field of view, and you might think, oh, great, that's pretty easy to do.
Russ Durkee:
But the problem is we don't always know to a higher degree of accuracy the brightness of the stars on every part of the sky. And so that is also a problem. You do this and you can see the brightness change over time. If it changes at a regular in a regular period like a sine wave, it goes up and down and up and down at a regular pattern, you can say, oh, okay, well, this object is sort of elongated or this object is sort of round because it doesn't change its brightness very much. And so that's a standard measurement of an asteroid light curve. And from that, you might be able to tease out things like its density. You might say that this object obviously must be solid rock, because if it was made up of sand, it would spin itself apart because it's rotating so fast. So you can get that with one object.
Russ Durkee:
But if you have a second object orbiting the other object, suddenly you can use Kepler's laws of motion to figure out things like the density of the two or you could figure out the relative size of the two and you get more information all of a sudden. And so it's a useful way to tease out information about the objects, but the way that looks in practice is instead of having a single curve going up and down at a regular rate, you might have an additional signal in there that you might have a smaller wave on the bigger wave that only appears periodically, or maybe you have an eclipse happening every now and then. So the wave will have a nice up and down character, but then suddenly, there's a dip in there. That would be an eclipse or maybe a partial eclipse or a shadow that's cast across the main object.
Russ Durkee:
You never really quite know, but you can tease it out to a degree and then say, oh, now we know what the density of this object is. And we know that these are two sandy objects, as opposed to two hard rock objects. And they're probably approximately so many kilometers across. This kind of measurement takes that added level of precision in order to tease out those extra little ripples in the light curve, which is why you need the cooling and why you need the latest, greatest camera and the bigger telescopes and so on.
Russ Durkee:
So I've been doing this for almost 20 years now. I tried to add up the number of objects that I've helped discover in this regard, because you need to have multiple people observing these light curves over and over and over just to be lucky enough to catch those little dips. Generally, it's not something that one person is able to accomplish. You're always doing this as a large group of people. And if you're lucky, you might be the first one to notice that binarity of the object, but you're rarely the only person that could pull it off. I don't know, I've been a part of maybe around 30 of these discoveries, but just since August, it looks like there was about nine of them, new ones that we were able to pick up.
Russ Durkee:
And so I'm part of a large research group that is based out of the Czech Republic. There might be 15 observatories that are actively observing these objects at any given time. And there's only two of us in the USA that are really active every month, but we constantly are in contact, we communicate through email groups and different things. We have these campaigns on a list of objects every month. Since the new camera has been installed, it's been a bumper year. I mean, nine and the last eight months or so is pretty remarkable. Partly it's due to the good site. We get maybe 150 clear nights a year, which is good, but it's not the best observing site. It's not like California, where you'd get 300, but still that's a pretty high success rate. And it's thanks to the camera being such a high quality thing.
Mat Kaplan:
Here's something that's just occurred to me. When you look at these light curves, which for a binary object sound like they might be quite complex, do you have software that helps you to tease out what that light curve is telling you? Or is this pretty much just your practiced eye and brain?
Russ Durkee:
No, it's the software because imagine throwing a pile of spaghetti on a table and trying to figure out all the different frequencies that are there, that sometimes it looks that bad when you look at the data. Now, most of the time, it's not. Most of the time you have a pretty well-defined curve and then it just looks messy, like there's an extra noodle in there that's not behaving, and you have to understand or try to figure out is that actually a real signal or is that just noise or a background star? You have to remember that these asteroids are moving throughout the night. And so your telescope has to follow them. If it passes near a background star, that might create a signal that looks exactly like a binary asteroid going around the star. And it might just be at the very limit of the visibility of the telescope. And so there is a little bit of that where you have to look at the data and see if you can spot a background star that's polluting the data, but the software is really where you can deal with this stuff.
Russ Durkee:
Through the software, you can subtract out the primary period of the asteroid, of the main asteroid, and then be left with some other frequencies there. And then you can look at it and say, yeah, that looks pretty good or it looks within the uncertainties that we have and there's probably a signal there. And then it takes a lot of extra effort to confirm that those signals are actually there. So while there is some parts of this that it comes with experience and skill of seeing some of these things that you really have to confirm it with data and with the software.
Mat Kaplan:
I'm glad you've got the right tools for the job. Certainly still takes a lot of dedication to be able to make this work.
Russ Durkee:
We've actually had a recent measurement of a binary asteroid that has changed its rotation rate slightly just due to sunlight pressure on the object. These systems are dynamic.
Mat Kaplan:
Solar sail asteroid.
Russ Durkee:
Yeah, exactly. And I know that the Planetary Society is into solar sailing for sure. And it does change. The sunlight will change the rotation rate of asteroids. If it just has the right combination of shape and sunlight falling on the thing, it's enough to impart a little bit of momentum onto the thing.
Mat Kaplan:
And another reason for us to keep a close eye on these objects that cross the path of our world. I just wonder if you ever think about what some astronomers of the past and in some cases the not so distant past, I mean, people like Edwin Hubble and Fritz Zwicky, a little bit further back, Annie Jump Cannon, there are so many, what they would have given to have a digital camera like this instead of old photographic plates.
Russ Durkee:
Oh, I can't imagine. I think about that every now and then, because of the limited time that's available under a clear sky with a resource like this, I think about what should I be doing with this equipment right now to get the most bang for the buck? And then I worry about, well, am I actually doing what needs to be done? Is this the best use of my resource? And I wish I could speak to those people and say, what am I missing? What really should I be doing with this? Because they would really know. There's like, why are you not taking spectra right now? Or why are you not? Maybe there's something even more important than NEOs, but I can't think of it at the moment. But yeah, I think about that because it's an embarrassment of riches, isn't it, to be able to connect to something that is reasonably reliable, 1500 miles away and make it do my bidding. And we live in an era where I could actually drive that distance if I needed to over the summer here and fix. It's crazy. It's an amazing time.
Mat Kaplan:
Golden age of astronomy. And Russ, thank you for being part of it. Congratulations once again on the great work that you're doing. And just keep it up. And I won't be surprised if we have reason to talk again sometime before too long.
Russ Durkee:
Yeah, I hope so. Keep up the good work and thanks for the support.
Mat Kaplan:
Amateur astronomer and Shoemaker NEO Grant recipient, Russ Durkee. We're one minute away from a trip to Sicily that will also take us to the asteroid belt and beyond.
Bill Nye:
Bill Nye, the planetary guy here. The threat of a deadly asteroid impact is real. The answer to preventing it? Science. And you as a Planetary Society supporter, you're part of our mission to save humankind from the only large scale natural disaster that could one day be prevented. I'm talking about potentially dangerous asteroids and comets. We call them near-Earth object or NEOs. The Planetary Society supports dedicated NEO finders and trackers through our Shoemaker Near-Earth Objects Grant program. We're getting ready to award our next round of grants. We anticipate a stack of worthy requests from talented astronomers around the world. You can become part of this mission with a gift in any amount, visit planetary.org/neo. And when you give today, your contribution will be matched up to $25,000. Thanks to a society member who cares deeply about planetary defense. Together, we can defend earth. Join the search at planetary.org/neo today. We're just trying to save the world.
Mat Kaplan:
We're back with the second of our recent Shoemaker NEO Grant recipients, Alessandro Nastasi wants to give you a tour of the GAL Hassin observatory in Sicily. He was there when we talked last week. Alessandro, it is great to get you back on Planetary Radio. It has been just about a year and a half since we last talk. And at that point, of course, you were one of those who had just received your Shoemaker NEO Grant. And I think we said at the time that we look forward to bringing you back and see what that grant had helped you to accomplish. And we'll be getting to that in just a couple of minutes here, but first of all, welcome back.
Alessandro Nastasi:
Thank you, Mat. Thank you to everyone for the invitation. It's such a pleasure to be here again.
Mat Kaplan:
We so admire the work that you have done with your colleagues there at GAL Hassin, as well as our other Shoemaker NEO Grant awardees over the years. Let's start up front by saying, I mean, you are not the only person who's GAL Hassin. It's quite a collaboration. You have two other people in particular that you introduced last time. Could you do that once again and tell us about Sabrina and Mario?
Alessandro Nastasi:
Sure. GAL Hassin actually is a foundation, [inaudible 00:45:52] foundation to information about that. Sabrina Masiero is our director, and also she is an astronomer and coordinating more or less our activities here in the center. And Mario Di Martino is another major collaborator, is a senior scientists, great expert on asteroids and NEO dynamics, things like that. So we are lots of people working, not even physically here at GAL Hassin, but in collaboration.
Mat Kaplan:
So we congratulate them as well, everybody there at GAL Hassin for the great work that you're doing and what you've been able to do with this grant. Sicily may not be the first place that people think of for astronomy, but there is some great history there. I remember you saying that a Ceres was discovered not far from your location.
Alessandro Nastasi:
Correct. Ceres, the first asteroid, the number one was discovered actually in Palermo, which is less than 100 kilometer from here by the astronomer Piazzi, a man working for church. And that he was working at Observatory of Palermo. Yes.
Mat Kaplan:
Number one and still the biggest in the asteroid belt. Pretty impressive achievement there. It is such a gorgeous location. I hope we're going to be able to share a video that you made for us. We asked all the winners of the most recent round of grants to make little videos for us that we're going to be sharing with members and some of our donors in an upcoming webinar, but your video is so great. I'm trying to get permission to do a sneak preview. And if we get that permission, we will put it on the show page, the episode page, this episode's page at planetary.org/radio. But let me tell you, first of all, you're a great tour guide, but it is just such a beautiful spot. It's like a park, almost an amusement park for astronomy.
Alessandro Nastasi:
Correct, Mat. We actually sit in a very nice landscape because our astronomical center is surrounded by some mountains, which actually helps to preserve the dark sky because block the light pollution from, for example, from the seaside or from the south. So we have a very dark south sky also since we are in Sicily, this is very south part of Europe, we have access to the Galactic Center, which is a very interesting target to observe. The video was created just for the purpose of showing the GAL Hassin landscape, where we work daily actually to the public. So yes, please share the video as much as you want. And yeah, thank you.
Mat Kaplan:
It really is gorgeous and the facility is so beautiful. I told you a year and a half ago that it really made me want more, even more to go to Sicily. And now seeing the video, I feel much more so that way. I would love to be able to walk around there. Did I see, did you have it look like a model of the solar system that people could walk around?
Alessandro Nastasi:
Correct. It's a panel with a series of discs where we show the solar system in scale. So the sun is a disc of two and a half meters. And then you in a glimpse, let's say, we have an idea of how the planets look like if we shrink the sun two and a half meter side dish. It's very impressive that you see that our entire life and history is reduced to a mere 1.5 centimeter disc down there and almost disappear. And actually the other way back, I mean, the other side of the tunnel show how big is the sun respect to the biggest stars in our galaxy. And again, I mean, when you see the sun shrink into 1.6 millimeter respect, for example, to the biggest red hypergiants, I mean, it's something that is shocking. Most people are shocked by this. I think it's useful for our egos or perspective, things like that.
Mat Kaplan:
Absolutely. I remember how shocked I was when I first saw how puny our sun is compared to some of the super giant stars in our own galaxy. There's something else that you showed us in this video. It's a beautiful little dome, which I take it as pretty new, inside is one of your telescopes, this 0.4 meter or 40 centimeter telescope. That dome is one of the results of this grant, isn't it?
Alessandro Nastasi:
Absolutely, yes. It's brand new because it's a 3-Meter ScopeDome that we purchased thanks to the funding of the Shoemaker NEO Grant in 2019. This allows us to actually move the telescope you mentioned, we call the GAL Hassin Robotic Telescope 1, so GRT1, outside the, let's say the area where I work, which is nice, but actually, which is mainly devoted to outreach activity with public. So I mean, since you have to open the entire hangar, it takes time and you're not probably active to observe the sky. Within this dome, actually, we take just seven minutes to turn on the telescope, the camera, open the shutter of the dome and point to the target. So it helps really a lot to get also efficient, because for example, in winter, we can operate just for short time because if the weather may change soon. I mean, we can observe just for one, two hours, target our NEO and then close the shutter with the dome. And this is very, very helpful.
Mat Kaplan:
I also suppose that that's important because I remember you saying that one of the things you specialize in at GAL Hassin is very fast followup observation so that, for example, if the Catalina Sky Survey notes a new asteroid, you folks are able to jump on that pretty quickly.
Alessandro Nastasi:
That's right. That's correct. In fact, when we, I mean, from some statistics, for example, when we follow up the NEO [inaudible 00:52:02] targets, we've been able to be like the first three in 70% of cases, the first one in 40% of cases. So we are quite fast in following up targets that are the most interesting one.
Mat Kaplan:
When we talked a year and a half ago, you were also getting ready to install a much bigger telescope, not at the GAL Hassin site. We should make clear it was not paid for by the grant, but there is a relationship here. Did that happen? Is that telescope now in operation?
Alessandro Nastasi:
The telescope is installed on the peak of the mountain. The name is Wide Field Mufara Telescope, is a one meter f2.1 prime focus telescope made by Officina Stellare. And is going to be like a prime tool for spotting NEO new, and actually is installed, but not yet operative as the camera, something has to be fixed for the cooling system, but we are confident that before the end of the summer, it will get to [inaudible 00:53:06]. And it will work in synergy with our tools because as you know, I mean, one of the thing that we purchase also thanks to the prize, the Shoemaker NEO Grant, is our timekeeping system. So we have a two timekeeping system to keep the two computer controlling synchronized. So they are going to work in strict synergy and collaboration.
Mat Kaplan:
When you talk about this synergy or connection between your existing telescope, the 0.4 meter and this new one meter telescope, how do you use those in a coordinated way that requires this very precise synchronization?
Alessandro Nastasi:
It's important, for example, for measurement of a parallax to estimate the distance of a target, but also when you have occultation events of stars, you can't estimate the shape of asteroids from his silhouette by occulting a star just with one instrument. You need at least two courts to have an idea of the sizes and some of the shapes. So with our baseline of eight kilometers, we may efforts observation like this. And so we may carry on observation of this kind.
Mat Kaplan:
So even with just an eight kilometer separation between these two telescopes, you expect that you'll be able to use parallax to triangulate more and get the location of asteroids more accurately, but also characterize them better as you're saying, by using, watching the occultation stars. And I assume maybe some of the photometric work that we heard about from Russ Durkee, although you folks, you really specialize in astrometric work, right?
Alessandro Nastasi:
Right. Although both our 0.21 and the future forthcoming WMT will have a photometric as long filters. So we can also characterize these objects in terms of photometry. And so the colors, but we are specialized in astrometry.
Mat Kaplan:
So it sounds like particularly once that one meter telescope is in operation, but it does sound like that the Shoemaker NEO Grant that you received is accomplishing what you hope for.
Alessandro Nastasi:
Yes. Definitely, yes. Already with our 0.4 meters, we've seen how hard we could go thanks to this funding and the dome and also the timekeeping keeping system really helped us in getting more efficient and faster and more effective in monitoring the NEOs, the fastest and the most interesting targets.
Mat Kaplan:
Fantastic work, Alessandro. Once again, congratulations to you and the entire team there, your colleagues at GAL Hassin. I sure hope to see it all happening in person someday. I can't wait to spend the night there with you at GAL Hassin, watching for near-Earth objects, and hopefully, not yet finding the one that is headed directly our way toward earth, but just doing the terrific science that can be done on these asteroids and comets that pass so close to our planet. Thank you and keep up the great work. Clear skies.
Alessandro Nastasi:
Thank you, Mat. Thank you. Clear sky to everyone. I conclude my video saying, and I hope to see you all at the GAL Hassin. So I wish really to see all you're visiting us. So thank you again.
Mat Kaplan:
Highly recommended. Alessandro Nastasi's video tour of GAL Hassin is on this week's episode page at planetary.org/radio. As promised, it's time for What's Up on Planetary Radio. Here again is the Chief Scientist of the Planetary Society, Bruce Betts. Welcome once again.
Bruce Betts:
Good to be back. Mat, It's been so long.
Mat Kaplan:
Yes. Simply many, many, many milliseconds since you last visited. What's up there in the night sky?
Bruce Betts:
Well, the evening sky over in the West soon after sunset, you've got super bright Venus, very easy to see if you've got a clear view to the Western horizon. It will keep getting higher in the sky over the coming weeks. And much dimmer, reddish Mars is up above that. And they will be growing closer and closer until they have a mid-July snuggle low in the West. In the pre-dawn or even rising around the middle of the night in the East is bright Jupiter. And to it's a right, yellowish Saturn. All right, we move on to this week in space history. 1963, Valentina Tereshkova became the first woman in space. Oddly, it would be another, almost 20 years before the second woman in space. But now they're flying all the time. Yay. Hard to believe it was 2004, SpaceShipOne became the first privately funded human to space mission.
Mat Kaplan:
Wait. That's right. I'm getting so old. That was the one I was standing on the tarmac. Holy cow.
Bruce Betts:
Yeah. That was amazing because you were still in elementary school.
Mat Kaplan:
Yeah. Yeah. I was very lucky that my uncle brought me out. No, I was actually doing it for this show even more incredibly.
Bruce Betts:
Yeah. You can go back in the archives and listen. All right. We move on to [inaudible 00:58:22].
Mat Kaplan:
I don't know what Bill's Science Rules! audience is going to make it that, but yeah, we do this pretty much every week, although he does it differently every week, folks.
Bruce Betts:
It's amazing and probably annoying. And for that, I apologize. But I've got a good random space fact to make up for it. We've talked about how enormous the sun is compared to the earth, you can fit a million earths inside the sun, but let's talk about the star Betelgeuse and Orion. It is so big.
Mat Kaplan:
How big is it?
Bruce Betts:
It is so big.
Mat Kaplan:
How big is it? I can't resist the Q line. It's like that scene in Roger Rabbit, Shave and a Haircut.
Bruce Betts:
It's so big that you could fit a billion suns inside, they don't choose. And so let me give you an analogy for this impossible to imagine. Oh, wait, it's not impossible to imagine. If you go to the Rose Bowl near me or any very large stadium, and imagine that as the size of Betelgeuse, then the sun would be about the size of a soccer ball and the earth would be about the size of a tomato seed hanging out on your burger at the game.
Mat Kaplan:
I love the universe.
Bruce Betts:
And it loves you, man.
Mat Kaplan:
I'm glad. It's the best of all possible universes.
Bruce Betts:
It is indeed. And that reminds me, we have a trivia contest. I don't know why that reminds me of that. So I asked you as of now, June, 2021, how many of the nine spacecraft that have visited Jupiter are still communicating with earth? How do we do that?
Mat Kaplan:
I know why it reminded you because these are the only spacecraft that are headed out across that universe. Well, one of them is not, come to think of it. Here is the answer from our Poet Laureate. Yes, we have a Poet Laureate, Dave Fairchild in Kansas, nine robotic spacecraft have gone by the planet king. Five of them are off the grid, a disappointing thing. The Voyagers are still alive and New Horizons too, while Juno keeps in contact from its polar point of view for spacecraft, right?
Bruce Betts:
Yes, indeed. Voyager 1 and Voyager 2, New Horizons and in orbit around Jupiter, Juno.
Mat Kaplan:
Here is our winner, Perry Metzker in New Hampshire. And here's what's interesting. Perry won exactly 365 days ago. That's including the leap day in the year 2020. We do have repeat performances here, everybody. Perry, congratulations. You're going to get a Planetary Radio t-shirt that can be checked out in the Planetary Society store at chopshopstore.com. Thanks for staying in the game, Perry.
Bruce Betts:
Congratulations.
Mat Kaplan:
I love this. I have to read it just because he's from Kuala Lumpur, Malaysia, a city I've actually visited. I didn't get to see much of it at all. It was just during a layover between flights, but [Jonathan Jone Shin Howe 01:01:32] says to these four spacecraft, thanks for all the awesome data and images. I've learned so much from them. Haven't we all, Jonathan?
Bruce Betts:
Yeah, that's for sure.
Mat Kaplan:
Not just one, but several, 2001: A Space Odyssey references Joseph Portray in New Jersey and Ian Jackson in Germany. Both mentioned HAL 9000, but of course, we haven't heard from him since 2010. I think Thorsten Zimmer in Germany, practical joker, Juno has already decided that at the end of her mission, she will transmit one final message, my God, it's full of stars. Nell Powell, one of our regular contributors in California. Plus those US government filmed unidentified craft if they visited Jupiter and are still talking to their advanced scouts here on earth. Bruce will neither confirm nor deny that he's one of them, but ask him anyway.
Bruce Betts:
I neither confirm nor deny that.
Mat Kaplan:
That's exactly what we expected. And finally, this from another of our poets, Jean Lewin in Washington, four of nine still stay in touch. And though they are far away, their mother earth still enjoys to hear what they have to say. But if one day one does return, the one that I would not wager will need to contact James T. Kirk, because it might just be future. Multiple science fiction references in this What's Up. We're ready for another one. Maybe we'll get some more sci-fi next time.
Bruce Betts:
First, a little background Betelgeuse. So we talked about despite being 500 light years away-ish is actually the third widest star seen from earth, the third largest angular diameter. And of course, the sun is first. Here's your trivia question? After the sun, what star has the largest angular diameter as seen from earth? Go to planetary.org/radiocontest. So what's the widest looking star when you look out from earth that's not the sun?
Mat Kaplan:
You have until June 23 at 8:00 A.M. Pacific Time to get us the answer for this one. And you will be in the running and could win if random.org picks your correct answer for this beautiful book that I mentioned upfront, Carbon: One Atom's Odyssey, lovingly and exquisitely illustrated by John Barnett with a foreword by Roald Hoffmann, the recent Nobel Laureate in Chemistry. It's basically the life story from the beginning of our universe of a carbon molecule or a carbon atom, I guess. It is absolutely gorgeous. It's published by No Starch Press by the way. And we'll put up a link on this week show page of planetary.org/radio, where you can also handle the contest. Bruce, we're done.
Bruce Betts:
Holy moly. All right, everybody. Go out there and look up in the night sky and think about tomatoes in space. Thank you and good night.
Mat Kaplan:
How many tomatoes in a mole?
Bruce Betts:
6.02 times 10 to the 23rd.
Mat Kaplan:
Boy, that's a lot of catch up. You can make a lot of moly. He's Bruce Betts, the Chief Scientist and sometimes chemist of 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 it's made possible by our more than 50,000 members. You can get in on the action at planetary.org/join. Editorial Director Jason Davis is filling in as our associate producer this week, Josh Doyle composed our theme, which is ranged and performed by Pieter Schlosser. Thanks and Ad Astra, Bill.