Planetary Radio: Space Exploration, Astronomy and Science - We have touched the Sun: The Parker Solar Probe’s triumph

Episode Date: January 12, 2022

The Parker Solar Probe dipped within the corona on its eighth encounter with our star. It found phenomena that have surprised and delighted heliophysicists, and it captured a movie that is one of the greatest space videos ever. We’ll talk about these and more with Nicola “Nicky” Fox, director of NASA’s Heliophysics Division, and Nour Raouafi, the mission’s project scientist. Get out your calculators! Winning the new space trivia contest will require some basic arithmetic. Discover more at https://www.planetary.org/planetary-radio/2022-fox-raouafi-parker-solar-probeSee omnystudio.com/listener for privacy information.

We have touched the sun, this week on Planetary Radio. Welcome, I'm Matt Kaplan of the Planetary Society, with more of the human adventure across our solar system and beyond. The Parker Solar Probe, named for 94-year-old pioneering solar researcher Eugene Parker, has gone where Parker probably never imagined a machine built by humans would ever go. On its eighth close encounter with our star, the spacecraft dipped within the sun's corona. What it found there is dazzling in every sense of the word. We'll talk about it with the director of NASA's Heliophysics Division,

Nicola Fox, and the mission's project scientist, Nour Afi. Then we'll hear how that star we race around is making it difficult to see our neighboring planets at the moment. Never fear, Planetary Society Chief Scientist Bruce Betts has much more to entertain us, including a new space trivia contest with a great prize. I've got a favor to ask. It has been years since we asked you to let us know how you feel about Planetary Radio in a survey. Here's your chance. I hope a lot of you will go to planetary.org slash survey and answer a few easy questions about this show. There's no obligation we won't bother you with other mail, and we're not asking you to become a member, though we wouldn't mind if you did, of course.

But I'll be very grateful if you help us out with this. Again, planetary.org slash survey. Thanks. JWST. Wow. It happened. Here's the almost anticlimactic moment when, on Saturday, January 8th, we learned that the new space telescope was fully deployed.

This is definitely done. We have reached the end of deployment, and we are preloading into the latch patch. All right. You see people clapping? Yes. Everyone's up on their feet and clapping. Now begins up to five months

of fine-tuning, including the careful, ultra-precise alignment of those 18 gold-plated mirrors. Like the telescope itself, our coverage of the JWST is just getting started. The Planetary Society congratulates NASA and the entire team behind this great new observatory.

The January 7 edition of The Downlink, our free weekly newsletter, covers the Biden administration's decision to keep the International Space Station operating through 2030. decision to keep the International Space Station operating through 2030. This is something I talked with Casey Dreyer and Brendan Curry about on our monthly Space Policy edition of Planetary Radio. The guys and I also mentioned the meteor that exploded over Pittsburgh on New Year's Day, and you'll find that story in the downlink as well. The image that made me do a double-take was the comparison of Jupiter's squiggly surface with a phytoplankton bloom in the Baltic Sea. I hope my colleagues didn't mix them up. They are uncannily similar. Nature loves to repeat itself. See for yourself at

planetary.org slash downlink. Imagine spending your long life learning and speculating about how stars work, and then having a space mission named for you actually visit one. As you'll hear, Eugene Parker is as thrilled by what is being learned as any scientist on the Parker Solar Probe mission, or any of the rest of us, for that matter. Nicola or Nikki Fox and Noor Rafi are no less enthusiastic, as I learned when I talked with them via Zoom a few days ago. Nicola, Nikki, and Noor, thank you so much for joining us on Planetary Radio, and congratulations on the stunning success

already of this pioneering mission. Thank you so much. Thank you so much. And it's amazing that after 60 years, we are achieving this. It's just amazing. We're going to get to the science. It's moments away, but I have to start with that utterly amazing, that jaw-dropping video. And I'm sure you know the one I'm talking about, actually touching the sun, as you put it, Noor. My colleagues and I at the Planetary Society, including our boss, Bill Nye, we were profoundly affected by that video, that first flight through the sun's corona. They agreed with me when I said I couldn't think of a space video that is more beautiful, more jaw-dropping, or more memorable.

If I could, I would nominate it for an Academy Award. Everybody needs to see that video. Thank you. It's fascinating that just a few years ago before the launch, when we were talking about the mission, saying, yeah, Parker Solar Probe at a certain point will be flying through the structures that we see during total solar eclipses. Personally, yeah, I think of it, it's true, but when we saw it,

we saw structures that are flying above and below the spacecraft. It is just amazing. It's kind of surreal that, yeah, we have something that we were touching just a few years ago, and now it's just flying through the structures that are just fascinating. I have to completely agree with you. The first time Nor showed it to me, I was in his office and he just had it up on this big monitor. And I kept saying, stop, wait, go back. No, no, wait, stop, go back, go back. I need to see that bit again.

And it was just so incredible. I remember saying, oh my God, we just flew through this. And go back, I need to see the whole thing again. And so it literally was like, I wasn't prepared for it. He just said, hey, I've got something kind of cool to show you because Noor's very laid back about these things. And I just was, again, doing backflips practically in the office over this amazing video. And you can imagine when N Nikki is excited about something. It is just, you know.

Well, as one of my colleagues put it once, Nikki was over the sun at your launch of this mission. Yeah, frequently am. The great Mary Liz Bender, a friend to both of us, I know. I got to say, it would have been fine if we had just seen those particles of the solar wind flying past us. But then, I mean, my God, they're light years away without being much affected by what we see surrounding your spacecraft is the Milky Way visible through all of that chaos. It's just spectacular. Yeah, it really is.

Nikki, we were talking just before we started recording about the last time, actually a couple of times, that you were on Planetary Radio when you spoke to my friend and former colleague, Mary Liz Bender, who interviewed you at the August 2018 launch of Parker Solar Probe. I know that was also when you transitioned from being the Missions Project scientist,

the job that Nour now has, to leadership of the Heliophysics Division at NASA. Do I have that right? Yes, that's right. About three weeks after Solar Probe left the pad, I left my own pad and I moved down to NASA headquarters, where I've been ever since. Yes, running all of the heliophysics division. So a tremendous portfolio with so many great missions, but Parker Solar Probe providing those inner measurements of our heliosphere. And then, of course, having Voyager all the way out in interstellar space. And so we really do cover

everything with heliophysics. You know, I hadn't thought about that. Here we are touching the sun and at the other end, we're feeling the end of the sun's influence across the galaxy. It's kind of a profound feeling, you know, that we are making these measurements. And then, you know, eventually the measurements that we're making with Parker Solar Probe Voyager is going to see all the way out there. So it really does encompass everything in our solar system. Just takes a few years to get out there. Eventually, we'll see it.

Let me ask both of you, why this mission and the goals that it had, why was it the goal of so many heliophysics researchers, heliophysicists like yourselves, for so many years being able to achieve this? Because it really was the most important question. How does our star work? How does it influence us here on Earth? How does it influence our entire solar system? We've looked at the sun in every different wavelength. I mean, we've done a tremendous amount of research. So even though it

was the highest priority 60 some years ago, we've done a lot of research in that 60 years. We didn't just sit there saying, well, we'll wait for the mission to launch. You know, scientists were really working on as many of the different problems as they can. And we'd sent missions in as far as the planet Mercury, but we'd never been able to travel through that region where sort of all of this physics is taking place, all the secrets are kind of kept of the star. And it just took that long to get technology to be able to allow us to do that mission. So it remained the highest priority because it was a question that really could not be answered or a set of questions that really could not be answered without this daring mission. And no matter what we did, it was almost like the more research we did, the more tantalizing

and the more important this question became because, you know, you find out something, but you still need to know that underlying principle. And so, you know, it's like looking out of your window and you know, you can see largely what the weather is like, but you still need to know that underlying principle. And so, you know, it's like looking out of your window and you know, you can see largely what the weather is like, but you don't know the temperature. You don't know how hard the wind is blowing until you go out into that environment. And so we've stared at the sun. We've looked at it in all different ways. But going up and visiting it was the only way to really answer these questions.

These problems we are dealing with are not easy problems at all. They are extremely challenging. As Nikki said, if you don't really go to the source where they occur, we will not get much insight into what is going. Because if you take the solar wind, for instance, when it leaves the sun, it propagates to Earth and beyond. It gets processed along the way. And by the time it reaches earth, all the signatures of the physical processes that gave it birth and accelerated it to very high speeds, they are all erased by the journey. So we need to go there. There is also another side to Parker Solar Probe, which is usually we don't talk much about it, but it's extremely important as well. Remember in the late 60s, early 70s,

when we landed man and the moon, that was a huge achievement. The achievement is on the technology side, basically that opened the gate wide open to space exploration. And we visited all the planets, maybe moons and everything. The only thing, the only object in the universe that we did not visit yet is a star. We are doing it with Parker Solar Probe now, and that is not an easy thing to do. Because our sun is no more than just a run-of-the-mill middling star, right? And we know, of course, that there are trillions, if not hundreds of trillions of them across the universe. So I assume that we are learning far more about how all of them work by studying the one that happens to be in our neighborhood. Yes, absolutely.

I joke with Paul Hertz, who's the head of astrophysics all the time, that, you know, the sun is a star, too. And he says he's always jealous because we have so many photons coming from our star and the ones that he looks at, they're very photon challenged. But yes, this is the one that we can go up and visit. And even though as Noor correctly said, it's incredibly hard to go and visit this star, it's a lot easier to visit this star than to visit the next one. And so, you know, we really are doing everything we can to learn about and characterize and fully understand our star and then use it to help understand other stars. You know, we know that other stars in other stellar systems, we know that they have flares. We know that they have storms.

You know, we know that there's some similarities. As you say, our star is an average star. It's kind of right in the middle of that sequence. And so, yes, totally applicable to what we're doing to other astrophysics and other stellar systems. There's an interesting point made on the mission website, which of course we will link to the Johns Hopkins University Applied Physics Laboratory website and also NASA resources and our own Parker Solar Probe pages at planetary.org. This interesting point is made that, of course, at least at this point, maybe this will change in the coming years. But right now, the only star we know of that has been able to support life

on the planets that surround it is the same one that you're visiting right now. So it sounds like there's a possibly at least an astrobiology element to this mission. Absolutely. Studying the sun up close and understand how it interacts with its planetary system, and in particular, the habitability zone, which is our Earth here, it is extremely important because once we understand how the sun interacts with the Earth and the other planets, we may actually get insights into other planetary systems in the universe and figure out which ones probably can have habitability zone that can harbor life. And as you mentioned earlier, there are trillions and trillions of galaxies, and obviously

each galaxy has trillions of stars in them, and many of them has planetary systems around them. The big question is, are we alone in the universe? Personally, my instinct says probably we are not. Why should we be the exception? But we might be. But there are big possibilities there, that there's life there. And coming back big possibilities there, that is life there. And coming back to the sun, as Nikki was saying earlier, understanding how the sun works and how it affects us here on Earth, it's crucial to astrophysics, to everything we study in the universe. And let me say one more thing. Usually when we talk about the sun and how its influence on us here on Earth, we usually have probably a negative connotation to it. That is, space weather can affect space systems, affects us, the power grid and all that. But actually it has a positive side that we often don't talk about.

Without the solar activity, that is flares and CMEs, life may not have kicked off on Earth. That activity was necessary to kick off life on Earth here. You're going to have to go further into that because I have always assumed, I mean, we talk now about those red dwarf stars, which are extremely active and that that may interfere with the generation of life in those other solar systems. How does a solar flare, something that can cause such havoc, how might that have contributed to the start of life on Earth? When you have solar flares and CMEs, they bring all the isotopes to the Earth system.

And that actually helps kick off the chemistry in the atmosphere, but mainly in the oceans. And that's what's crucial to a kicking out flight out there. And there is research in this that's saying without probably the solar activity, we probably life would not have existed on Earth. Other than the evidence that is before our eyes in that wonderful video, how do we know that Parker Solar Probe

has actually entered the corona, that it has touched the sun, in your words, Noor? The easiest way is the video you mentioned when we are seeing that Parker Solar Probe is gliding through the structure. It's fascinating, and we know the structure belongs to the solar corona, so we know that. But the tangible evidence that we got, we got actually from the fields and particle measurements. And there is a boundary that separates the solar corona from the solar wind. The solar corona is magnetically dominated and it rotates rigidly with the sun. The solar wind is not. And when we cross that boundary, we know it from measurements of the magnetic field and the densities of the solar wind.

We can compute what we call the magnetic Mach number. And when it is below one, it means that we are into the solar corona. That's actually the hardest evidence we got that we actually transitioned into the solar corona. Nicky, I'm going to stretch a metaphor here because when I read about what Nora's just talked about on the website, this border between the sun's atmosphere, the corona, and further out in the solar system, it brought me back to Voyager. And I was thinking of detecting the heliopause, which we now believe, is it both of the Voyager spacecraft?

Yes. Yes, have now passed. Is that in any way a fair comparison? I don't think it's magnetically related. It's a comparison in that it's a boundary, and it's a boundary between very different conditions. And of course, with Voyager, we saw sort of all of the sun's activity kind of switching off, and the activity we expected to see with interstellar space coming up sharply. We were able to see it better with Voyager 2 because of the instrumentation that was still working. But yes, we knew we'd crossed the

boundary. Now, you know you crossed the boundary, you have to double check, triple check, make sure all of your instruments are seeing the same thing. One instrument alone can have signatures that make you go, hmm, I think we crossed the boundary. But you really need to see all of the coordinated measurements to make that full determination. And that's why Solar Probe is so great, because we have all of the complementary measurements that mean that we can definitively say it. We saw the magnetic field increase as we had predicted it would.

We saw particular wave structures that were sort of shimmering along this increase in the magnetic field. And we saw that with our magnetometers. We saw that with the wave antennas. We saw the plasma measurements do exactly what we thought they would see as the density increase too. And so, you know, it's sort of putting all those pieces together, but yes, it is a boundary. It's not a solid boundary. The sun doesn't have a solid surface. The corona doesn't have a sharply defined, it's really a surface. And so, you know, we crossed it at one particular location on this orbit that we're discussing. As we cross it on other ones,

we certainly don't expect to see it at exactly the same point because it's really like a rippling surface. And so just like if you dive into the ocean you know you dive in at different heights of the waves depending how the wave is cresting at the time so that's basically what we're doing with solar probe we dive into the corona beneath this this boundary and we look forward to doing it on all of our upcoming orbits she predicted bravely and they can tell you actually we are we actually did. So we did it actually for a longer time. And for what Nikki said earlier is pretty why it took us so long to announce the news, because we wanted to check and recheck and recheck everything that we are calling it is right,

because this is an important milestone for the mission, but also for science. We are actually entering a new regime of the solar wind. We are flying through the region where the solar wind is born and gets accelerated. And this is extremely important. We have been waiting for this for 60 years now, and we are doing it. Obviously, a lot of this is coming from knowledge that we already had, what we thought we could expect. But you're also being surprised by some of what you're finding at the Sun. And I'm thinking, in part, you made me think of it, Nikki, because you talked about that very uneven surface with quotation marks of

the corona. And there are some animations and illustrations of this on the website. It's quite wavy. It's quite irregular. Do we know why that is? I mean, in a way, it seems natural, but I wonder if we understand the mechanism behind it. Well, I think if you look at the sun, I mean, if you look at beautiful images from like, you know, STO, for example, you see all the different activity, you see, you know, bright spots, dark spots, and the sun is always roiling and churning and, and it doesn't have a solid surface. And so the, you know, what you see is the surface is just where your eye kind of says, okay, that's, that's where the surface is, that's where you're sensitive to the light. The actual surface of the sun is also wavy and undulating and

continually moving. And so it's really driving the corona. So the corona gets held at a certain distance above the sun by various different processes. As those processes change, the location of the boundary will also change. It's like you have the ocean, but you have a gazillion of tributaries that are all getting to the ocean. And all of them have different properties in a way. So you don't expect this boundary to be the same for all of them because they all have different properties. It's a chaotic system, right? Very.

A lot of factors here. Is there a way to categorize the strength of the magnetic field of the sun? I mean, is there a comparison that could be made to Earth's magnetic field? Because clearly this magnetic field is incredibly powerful and is driving a lot of these phenomena that you see as Parker Solar Probe dips down into the corona. Yeah, absolutely. In terms of the physics itself, the physics is more or less the same, but these are different regimes. For the Earth, the magnetic field is mostly static. At least in the inner part of it, it's mostly static. For the Sun, it's completely different. The Sun is changing all the time. You see the Sun today,

it's different. In one hour, it's different. Tomorrow, it's different. Next week., it's completely different. The sun is changing all the time. You see the sun today, it's different. In one hour, it's different. Tomorrow, it is different. Next week. So it's not the same at all. And that is actually what is fascinating about stars in general. They are changing all the time. And they can do amazing things that some of them you can expect, some of them you don't expect.

And that's exactly what we are seeing with Parker Solar Probe. We are seeing so many things that we didn't even imagine them before. They are absolutely completely new to us. I'd like to talk about some of those surprises that you're running into. It has been given by you and other heliophysicists, this fascinating, but very descriptive name. Tell us about switchbacks. So switchbacks, that was something that we were not expecting. The very first orbit, we saw those switchbacks. And, you know, I remember being at the AGU meeting, American Geophysical Union meeting, with a standing room only packed.

And it was the first few bits of data that we had because we'd only just got this data down. So it was literally hot off the press i remember this particular plot being shown and it just showed the magnetic field line it's a it's a simple plot it's a black and white line plot and it showed these things and you could hear audible gasps in the room because a it's the first time you're actually seeing the sun's magnetic field up close and so that's you know that's kind of a powerful moment as well but just seeing how how dynamic it was because you know i think everyone sort of thought well you might see a current sheet crossing you might go from sort of above to below and you'd see a change but this was just going all the time and and again that took a

little while and we had to get the other data sets down and look at how the plasma was changing in response to these magnetic fields. And so what we actually saw was these sort of S-shaped curves in the magnetic field, which is really surprising because now you have plasma. You have things moving back towards the sun. I mean, if you think about it, you expect it to come out. Now it's going back and curving back out again. Like a switchback on a mountain trail. Just like a switchback. Exactly. And it's not clear how they form because if you think about taking a garden hose and twisting it, you actually have to put quite a bit of energy in to get that

garden hose twist. And the first thing it wants to do, spring back out again. And so we knew, well, hey, whatever's causing these, as soon as they relax and you can see them relaxing in the data as they move further out, wow, that's letting out a ton of energy because you somehow you put energy into the corona, into the magnetic field, it relaxes, it lets out energy. And there's your smoking gun for why we're seeing energy deposited in the corona. That was a big, big surprise. And that was surprise number one on orbit number one. And that was when you knew this mission is going to give you more and more surprises and more and more fabulous data the longer the spacecraft flies,

because no one expected anything like that on the first orbit. The meeting Nikki was talking about, actually the session at the AGU we're talking about, was Thursday morning. It was 8 a.m., I believe. But two days before, it's on Tuesday when we got the data. And we were sitting at the Smithsonian. And when we saw that plot Nikki was talking about, the initial thoughts was,

what was going wrong with the instrument? Exactly. Yes, exactly. It took us probably 10, 15 minutes to realize, wrong with the instrument? Exactly. Yes, exactly. It took us probably 10, 15 minutes to realize, no, the instrument is actually right. It's working perfectly fine. And what we are seeing is new physics. It's something. And while these switchbacks, I mean, we saw them before with other missions,

but we see one every now and then. They are so rare further out in the solar wind. What Parker Solar Probe showed, as Nikki said earlier, you see a jungle of them when you get closer to the sun. The mystery about them is where do they form, how do they form, and how do they evolve in the solar wind? As Nikki pointed out earlier, the energy they carry out will dissipate at a certain point, but how that is done, it is not clear yet.

Does this possibly partially answer that question that heliophysicists have wondered about for over a century, which is how can the inner surface, so-called, of the sun be, what, maybe 10,000 degrees Fahrenheit, but the corona is millions of degrees hotter. Could this be part of the explanation? It could be, but we do not have a firm answer. I mean, what is the contribution of the switchbacks to that phenomenon? It is not quantified yet. We are moving toward that goal. But what is clear, they are a potential contributor to the heating and the acceleration of the solar wind, definitely, because as Nikki said earlier, they carry a ton of energy with them. And when you move further out in the solar wind,

these switchbacks kind of disappear. So they must have dissolved, they must have dissipated somewhere through turbulent processes and things like that. And all that energy they carry with them, it is transferred to the plasma in the form of heat and speed. And that actually links back to the coronal heating problem that was discovered in the late 30s of the last century. And also the acceleration of the solar wind that is over 60 years old problem. We call it the smoking gun. It's definitely not fully answered yet, but that's why the mission is a seven-year mission. If you thought you were going to answer everything on orbit one, you wouldn't need to keep going in.

But as Noor alluded to, the closer we get to the sun, the more of these switchbacks we see, and they're getting larger. And then we actually, I think, as we're getting closer, we may actually see less of them. One thing is fascinating about this mysterious phenomenon that we are seeing of switchbacks. There are a big debate now, where do they form? There is one group that says, well, they form at the base of the corona where the solar wind is bored, and they get convected by the solar wind. Another group says, no, no, that's not the case. They form in situ in the solar wind. So that's a natural evolution of the... And in a way, if we solve that problem

of the formation of the switchbacks, we might actually be selecting between the two most prominent theories of the solar wind. That is magnetic field of connection and turbulence. I mean, for years and for decades now, we don't know which one of these theories is probably the right one or contributes most to the acceleration of the solar wind. So it sounds like you have the potential here

to solve, I mean, this could be part of Parker Solar Probe's legacy, figuring out which of these two models is correct or more correct. I mean, it makes me think of, you know, back when we didn't know if craters on the moon were caused by volcanic activity or meteors, and that has been resolved. Would this be of that sort of significance in heliophysics? Definitely, if not even more important to heliophysics. It really is the key question for us, and Nora is absolutely right. Right now, we have two theories. We hope we will distinguish between them. There could be a third theory. It could be a combination of both, with one being a higher contributor in certain conditions

and the other being a higher contributor in other conditions. And so this is what we really need to unpack. But, you know, boy, the switchbacks are a great signature to get us started. Nikki Fox and Nour Rafi will add more illumination to our understanding of the sun and the Parker Solar Probe in less than a minute here on Planetary Radio. Hi again, it's Casey Dreyer, the Chief Advocate here at the Planetary Society. Our 2022 Day of Action is set for March 8th.

This is your chance to advocate on behalf of space science and exploration. If you've heard us talk about how effective and just personally rewarding our past Days of Action have been, this event is for you. Learn how to participate in this virtual online experience by visiting planetary.org slash dayofaction. If you live in the United States,

we'll book your congressional meetings for you and also provide you expert training so you can be the best advocate possible. If you live outside the U.S., you can still make your voice heard on March 8th. It all starts at planetary.org slash dayofaction. Join us as we speak out for space. Just to stick with these switchbacks for another moment, how far down have you been able to trace their generation? Because it looked like, as you were saying, Nora, in one of the theories, they're coming right from,

I'll use the word gingerly again, the surface of the sun below the corona. Talk about visually impressive. That's where these things called supergranules are, which really have to be seen to be believed. When we look at the solar surface, the magnetic field elements that are brought from the interior of the sun, they organize a network that we call supergranules. These are huge cells, and the magnetic fields are concentrated on the boundaries of these cells. And the magnetic fields are concentrated on the boundaries of the cells. And the magnetic field, when it expands into corona, it forms what we call funnels. And these are magnetic field structures where the plasma is flowing outward all the time.

So with the most recent paracrysolar probe data, we actually could trace signature of the switchbacks to these supergranules. They have some correlations between them. And the supergranules is a potential source of the switchbacks. If I put it in a different way, that is probably favoring more the magnetic field reconnection scenario of a turbulence, but that is not the full story because from earlier data, there is other evidence saying probably the switchbacks are also formed in situ. So this conundrum of the sources of the switchbacks, we are far from solving it now.

We will continue with it for a while. Such is science. Nicky, what are some of the other surprises or data that we are getting back from Parker Solar Probe that you are really proud of? It's somewhat related to the switchbacks, but I think the finding that somewhat close boundary or very sharp boundary between where the solar wind is kind of accelerating and moving directly radially away from the sun as to where it's still moving rotating around with the sun as a solid body we didn't expect to see that so early either you know and that's if you think about um justin casper his his great um explanation is we think of a child on a on a merry-go-round or a carousel going around with the the carousel but

if they jump off or they sort of took a run and jumped off, they'd keep going straight, but the carousel keeps going round. And so we saw that at a pretty sharp boundary and further away from the sun that we were expecting to see. And again, this is all done in the early orbits. So things where we thought we'll get to characterize the outer area of the corona for a couple of orbits and then we'll finally do enough Venus flybys that we'll get into that region of interest. We were in the region of interest from the very beginning. So all of these things were seen on orbits one, two, and three. So that was before the second Venus flyby, before we took the next step in,

that we were seeing all of these things. So that's probably my favorite one that tells you about the history of a star and can tell you about how the star matures. That probably was my favorite one other than the spectacular images that you've already talked about. And I think seeing the Milky Way, again, you mentioned that in the video,

but we saw the Milky Way, that was our sort of first light image from the coronagraph was a Milky Way image, an absolutely stunning first light image from the coronagraph was a milky way image absolutely stunning image from a white light coronagraph so some of those things are just just really beautiful and and you know we're very proud of all of the instruments and all of the scientists and all of the instrument teams that are working so diligently on not just the science but also producing the data for countless other scientists to work on as well. So it's just a great team. The phenomenon that Nikki mentioned of the excessive tangential flows further out in the sun is extremely important. And it's not only

important for the sun, it's important for stellar physics in general, because one of the big problems is how stars lose angular momentum. When stars are born, they are rotating very fast, but as they age, they slow down. For the sun, we rely on models. We don't have measurements at all. And Parker Solar Probe is providing us with the very first measurements. And the measurements that Parker Solar Probe is giving us, they are quite different from the model that we thought is right. I mean, it's amazing. If that holds,

we have to revise all these models. And by the way, the stellar models are all built on the solar model. So we have to revise all that in a way. Another thing, we thought that we would have evidence, some evidence for it late in the mission is what we call the dust free zone and the dust free zone was predicted over 90 years ago in 1929 by a physicist called henry russell and he was studying i mean micron sized dust around the stars and he says he was predicting that should be a zone around each star where there is no dust at all. In a way, these dust particles, when they get close to the star, they get so, they got so hot to the point of sublimation. And once they sublimate, they get cleared out by the solar wind and other phenomena.

So there is a vacuum in terms of dust around the star. But for 90 years, we looked for it over and over and over again, but we had no evidence whatsoever for it. But for 90 years, we looked for it over and over and over again, but we had no evidence whatsoever for it. But from orbit one, Parker Solar Probe gave us the very first hint that the dust-free zone exists around the Sun. And by the way, that discovery was not even in the prime science of the mission. I may come back to dust because I know it can also be a challenge for you for the spacecraft. But I just wonder, before we move on, are there any other findings you would want to call our attention to as the probe continues its work?

Waves is one of the big things we are looking for in plasmas in general, particularly in the solar wind, because waves, they are one of the potential phenomena that will heat and accelerate the plasma. Because once the wave loses energy to the plasma, that's where it goes in heat and acceleration. With Parker Solar Probe, we saw all sorts of waves in the solar wind, which is expected. But one thing in particular is very eye-catching. When we have the quiet periods of the sun, we see a lot of waves.

But when the switchbacks come in, these waves kind of disappear. We don't really understand why that happened. And it's another side, if you wish, of this mystery of the switchbacks, why they behave in that way, why the plasma behaves in that way when we have switchbacks and when we don't have them. That's another fascinating thing that we still don't really have. We don't understand it yet. Nikki, you already mentioned SDO, Solar Dynamic Observer, I believe,

that other farther out spacecraft that is staring at our star. I wonder how you see Parker Solar Probe as complementing, as being part of an integrated study of the sun that includes SDO, but also the great solar telescopes down here on the surface of our world. Yes. So actually, one of the great things about being the heliophysics director is I get to play with all of these spacecraft and put them together in interesting ways.

And so, you know, it would be remiss if i didn't mention the issa nasa mission solar orbiter which launched uh in 2020 and is uh now coming in for their second closest approach of the sun themselves it's a very different kind of mission uh they're further away from the sun they're kind of a they'll be around a mercury but the reason for that is because they have all these spectacular cameras and remote sensing instruments that you couldn't have them so close to the sun. So we need to keep them a little further out. But the synergy between the two missions is just staggering.

And to have them flying at the same time is just wonderful. We will be really up close flying through these structures while Solar Orbiter is imaging those structures. And as they as they do their maneuvers, you know, we use Venus to take us closer and closer to the sun. They're using Venus to kind of take them out of the ecliptic. So they'll actually be able to view the poles of a star. And that's the first time we've really viewed the poles of a star. And so now, you know, you're looking at maybe activity from the next solar cycle that may move down to the equator over the course of a solar cycle. Putting these two together is just amazing. DECIS is the new telescope, ground-based telescope, will take

unprecedented measurements of our star. And so, you know, to have these three sort of giant observatories that are just answering these incredible questions and have them all working together is just spectacular. Every time we have a campaign where the footprint of Parker Solar Probe is visible from the Earth, so when that closest approach is on the Earth side of the sun. We actually have campaigns where just about all of the ground-based solar telescopes are operating and taking what we call campaign data. They're really focusing on the science that will really add to Parker Solar Probe. We've had a couple of those. The upcoming closest approach that will be occurring next is one of those amazing cases. And all of those

solar telescopes will be staring at the sun and really characterizing what Parker Solar Probe is flying through. We have new missions that we've just confirmed that we'll be also adding based on the great work that Parker Solar Probe is doing now, honing their science questions to take into account the new discoveries of Parker Solar Probe that were not available when they were writing their proposals because we hadn't launched yet. And so we have Punch, four small spacecraft that will be kind of looking at the sun from the inside out, really focusing on the region inside and how these things are born. We have Sunrise, six CubeSats that will go out and separate and form one giant radio receiver dish. But by adding the data all together, something we could never have done a long time ago. But again, they're

focusing on the waves that Noor talked about, and the wave signatures of these big events coming out. So Parker Solar Probe already having a profound effect on our future missions. I will try to bias the discussion toward Parker Solar Probe because I have to be a little bit biased. And I'm objective here. When we look at data from other missions like SDO, for example, Solar Dynamic Observatory, we always have in mind what Parker Solar Probe is observing when we are looking at that data, because we are trying to link both what Parker Solar Probe is measuring in situ and what SDO is observing remotely.

And now we are getting closer and closer to the sun. We are seeing that link becoming stronger and stronger. We kind of know the signature of the physical processing mechanisms that are occurring at the base of the corona and what are their effects on the solar band. So we kind of see it now. But let me also come back to the campaigns that Nikki mentioned earlier. And this is just for history.

The first one, the first encounter that gave us opportunities for synergies with the ground was Encounter 4. encounter that gave us opportunities for synergies with the ground was encounter four. I sent an announcement asking, basically soliciting support for Parker Solar Probe. And honestly, we were hoping for a handful of observatories to support us. But we got actually over 50 observatories worldwide supporting us. These observatories are doing all sorts of observations to support Parker Solar Probe. What that tells us is that the community is so enthusiastic about Parker Solar Probe, and they are all coming together, trying to understand how the sun works and how to get that, basically, all type of data that will help us to get there.

When I hear these bits of this ongoing story, the study of our own star, I cannot help but thinking of the scientists and observers, perhaps across all of human history, who've been looking up at it in wonder, hopefully not staring right at it. Hale is a great example. I mean, he's mostly known for building the biggest telescopes of his day, but his own research, his lifelong fascination was the sun. And I cannot help but think of how much he would love the work that you are doing with Parker Solar Probe in coordination with all of this other great science that is underway. Nikki, do you ever think about that? science that is underway. Nikki, do you ever think about that? Oh, actually, I do. I mean, I often describe, you know, heliophysics is a somewhat new term to describe what we do. I often say, probably it's the oldest branch of science, because the first people looked up at the sun and thought, I wonder what that is. And they knew it had a profound effect on what they were doing, even though they may not understand it. And so that sort of sense of wonder of this thing in the sky that is actually determining our quality of life here on Earth, it just really, to me, makes us the oldest branch

of science. Also, I keep in very close contact with Dr. Eugene Parker. And I recently went out to visit him at the end of last year to actually present him with his Crawford medal, which was a very big deal. And I got to go do that. And he is absolutely captivated by everything that we are doing. He wants the latest papers, he wants the preprint, you know, I often send him the preprints of papers. I'm like, don't tell anyone about this, read the preprint, but know, I often send him the preprints of papers. I'm like, don't tell anyone about this. Read the preprint, but we haven't published it yet. And you know, and he will often engage with the researchers themselves and say, you know, hey, I'm really excited about this, or have you thought about doing it this way?

And, you know, so just having him still so excited about the mission that bears his name, I mean, who wouldn't be excited if you have a mission named after you, but, you know, he is just really in there and talking to some scientists who have been in the field for a long time that just say they're so excited and so grateful to see this mission actually flying during their lifetime, because, you know, you don't know that's going to happen. And they're the ones, the giants that came up with the science that we do. So I think it's just a very, very profound mission. So Nikki, at 95 years old, would you still describe Gene as a kid in a candy store when he sees data from Parker Solar Probe and things like that?

He is. I went out, I think on the one year anniversary of our launch. I went out and actually showed him some Whisper movies. That's one of your instruments, of course. That's one of the instruments that actually, I'm sorry, yes, the white light imager that took the movie that you were talking about at the beginning, you're showing him those images and actually that image with the Milky Way through it. And you can see all of the planets in there. And, you know, he was just like, wow, that's what the solar wind looks like, you know, and yes, the more data he gets, the more excited he becomes, I think. So definitely, even at 95 years old, still super excited about everything that we do. You know, even he'll sort of, come tell me, come tell me what's going on, you know.

And whisper in my ear so nobody else hears, but tell me what's going on. So yes, he's fabulous. I get the strong sense that I am talking to two more of those kids in the candy store. Noor? I think we are all kids after all. I think we are all excited by stuff we are looking for.

It is fascinating. Well, we are, I think that's our job. That's what we are doing. We are doing science. And what is fascinating to me is the unwavering enthusiasm of the whole team from the get-go until now and in the future. It is amazing how these folks are basically putting everything behind this mission. It is amazing how these folks are basically putting everything behind this mission. Just a few days ago, when we had a small snowstorm here in the middle of the night,

there was something that needed attention right away. And we had folks just drove through the snowstorm to the Mission Operations Center to deal with it. That was in the middle of the night. It was at 2 a.m and it's it's it's just just fascinating how everybody wants to see this mission be the mega success it should be and and there is no reason it should not and i think also you know i don't want to miss out on the fact that we're doing venus science as well you know when we fly by the planet venus we were able to actually keep the instruments on at, we thought that we may have some power margins and we may need to switch them off. But we were able to keep those instruments on even from the very first flyby.

We've had one where we've taken spectacular images of Venus again with our white light imager. So the planetary community is excited about the results that Parker Solar Probe is giving them from the planet Venus. So we really do cover everything. You know, we're covering, we're helping the astrophysics with the sun as a star too. And this is rewriting the models for other stellar objects. We're providing support to the planetary. And, you know, we're telling everybody more about how planet earth responds to what is coming from the sun. So we really are covering everything. And you asked earlier about like how the sun and the Earth's magnetic fields compare. You know, I kind of think of the Earth's field, it's about half the overall, half the magnitude of the sun's

magnetic field, but the Earth's field is kind of there to protect us. The sun's magnetic field is causing the chaos that the Earth's magnetic field is protecting us from it's a just a relationship between those two magnetic fields both doing very different things both having a big effect on our ability to live here talking about venus and just as a teaser there is a new discovery that we will announce in the next few weeks it's fascinating observation we cannot talk about it now as nikki was nik Nikki held a finger up to her mouth. She said, be very careful, Noah. It's coming. It's fascinating. And as Nikki said earlier, this is all bonus science, and there is a ton of it out there. I bet you are delighting the teams behind those three

new missions that are headed to Venus. As you delight the rest of us with everything that you are revealing in the bright light of the sun, I hope that Parker Solar Probe can keep this up for many, many more encounters. I know it has to be a very difficult environment, but my goodness, those engineers on the mission have certainly served all of us well, and especially you, the scientists who are now revealing our star to us. Thank you so much for this conversation, and best of continued successes as Parker Solar Probe continues its work. Thank you so much. It was a pleasure to talk to you. Thank you so much, and the goal, I think, is to make Parker Solar Probe a mission for the ages. We want people to

be working with Parkasoloprobe 20, 30, 40 years from now. Absolutely. Don't forget, it's the coolest, hottest mission under the sun. There you go. There you go. It's time for What's Up on Planetary Radio. So I have sitting across from me virtually, the chief scientist of the Planetary Society. It's Bruce Betts. Let me read you something. This came from Steve Sheridan in California. Matt and Bruce love what you two are doing for the space community, informing and entertaining us every week. Please keep up your excellent work.

Nice, huh? Yep. Checks in the mail. Thanks, Uncle Steve. Welcome. Thank you. All right. Well, let's do our sky thing that we occasionally do every week.

I don't know what I did in the evening, but I have scared the daylights out of planets. They are all running till the morning sky and knowing there is no way I'm going to follow them there. guy and knowing there is no way I'm going to follow them there. We still have Jupiter being brave in the low in the west in the early evening and to its lower right, Saturn. Mercury even coming to play with Saturn for a few days, but then everyone's running away. Venus has already taken the bus, the boat, whatever. It's popping up and very low in the pre-dawn east, but it'll rise very quickly. So by the end of January, it'll be quite easy to see. And we'll be catching up to Mars. That's just kind of been chilling in the east, in the pre-dawn sky. So still we're splitting evening and morning and we'll be doing morning for all these planets within a few weeks.

doing morning for all these planets within a few weeks. This week in space history, a couple cool things from the OTS, the 2000s. 2005, ESA's Huygens lander, part of the Cassini-Huygens mission, went through the Titan atmosphere over a two and a half hour period and successfully even landed on the surface of Titan, a billion and a half kilometers away from Earth. And then 2008, Messenger did its first flyby of Mercury, solving my enormous curiosity and other people's for what that other half of Mercury looked like, since we only saw roughly half of it from Mariner 10. Two great accomplishments. We move on to... Random Space Fact! It's like the Cowardly Lion.

He's trying to roar. All right, here we go. I think you'll like this one, Matt. It's just odd enough. I did some calculations. The International Space Station has a mass approximately equivalent to a single-story house with an area of 465 square meters or 5,000 square feet. So it's mass, if you had dropped it on the Earth, it would have the same weight as a single-story, 5,000 square foot, 465 square meter house. Which is a good-sized house.

Somebody who has a house that's 5,000 square feet, maybe especially if you dropped it into the Hollywood Hills or Bel Air or someplace like that, could afford to build a house that looks just like the International Space Station. Well, we'll see if we prompt any of our well-to-do listeners to do such a thing. Oh, man. We put the bug in their ear. Yeah.

Kind of like that thing in checkouts here and star trek 2 oh yeah oh gross oh it's horrifying couldn't lick an air wig in the eye never mind um all right we move on the daylights out of you huh yeah exactly i almost went to the morning sky. All right. Trivia contest. I asked you how many deep space, by which I meant to the moon or beyond, launches. Launches were there in 2021. How'd we do, Matt? Notice how he repeated launches, because we think some of you might have counted, well, a couple of spacecraft as separate launches when they were really on the same rocket. But more about that in a moment. Here is an answer

from our poet laureate, Dave Fairchild in Kansas. 2021 had launches, rockets flying high. There were just a trio that have left our friendly skies, by which I think he means between here and the moon. Left are friendly skies, by which I think he means between here and the moon. Lucy left for Trojans, dart for Didymos. Who's three? Her golden hexagons aflame. We have JWST. I hope it's hexagons don't catch fire.

It'd be tough in space. We're going to get another rhyme of three and JWST before we're finished here. But was that correct? That is correct. That is correct. That is correct. Lucy Dart and JWST. And Dart includes another spacecraft along with the main spacecraft, an Italian CubeSat. Here's our winner, Joseph Ladd.

Congratulations, Joseph. First time winner. He has been listening and entering for over five years. I believe he's also a proud member of the society. He has been listening and entering for over five years. I believe he's also a proud member of the society. He's in Nevada. He says, I found three. Sure enough, Lucy Dart, JWST.

Hope I'm not missing any. He also adds, looking forward to the day of action, as are we all, Joseph. So I guess he'll be joining in where people can learn about that day of advocacy for space exploration at planetary.org slash day of action, all one word. Thanks for allowing me to throw that in there, Joseph. He's going to get one of those 2022 International Space Station wall calendars that we've been talking about. Wear it proudly on your wall, Joseph, and thanks very much for listening. Yay. A lot of people suspected that you were up to something beyond what they could easily find.

Burton Caldwell in New York said, I think there's a trick in this question we're all missing. Mel Powell in California made it much more overt. He said, I'm terrified that I'm wrong. Curse you, Bruce Betts, evil genius. I will never let you toy with my emotions again. And then, narrator, he would enter the contest the very next week and let Bruce toy with his emotions. See, the great thing now is I've toyed with everyone's emotions so much that even when I ask what is basically a straightforward question, they actually become suspicious that it's not straightforward. If you ring a bell, they may all start drooling, too. A little bit of a curb there, I noticed at the end. Ben Drought in Iowa, he even gave us the rockets. Atlas V is what took Lucy up. It was a Falcon 9 that DART was on the top of, and that

other Italian CubeSat. And an Orion V, of course, as many of us saw, a big Orion V that set the James Webb Space Telescope on its way. We have this last contribution from Gene Lewin in Washington. All in all, for orbital, 146 were tried. Most were planned for low Earth realms, a small percentage, though, denied. Of those that launched with deep space plans, the total count was three, Lucy first, and then to Dart, and last, JWST.

Three, JWST, it's like, yeah. Great minds, huh? Yeah. I've got a new, after all this time, I believe this is a new style of trivia question. It sounds really complicated, but I think some of you, like you, Matt, can probably solve it in your head. We're doing math. That's right. We're doing a math problem. First of all, all of the following things I will mention are about telescope primary

mirrors, primary mirrors. So here's your math problem. What is the sum of the number of hexagons of one Keck 10 meter telescope divided by the number of JWST hexagons plus the Palomar-Hale telescope diameter divided by the Mount Wilson-Hooker telescope diameter. Oh, my God.

Go to planetary.org slash radiocontest to get your numerical answer to that math problem to us. And let me toy with your emotions and your mathematical brain. Oh, he's put a hex on us, people. And if you got lost in there, remember that you can see it on the contest page that Bruce just gave you, planetary.org slash radiocontest. It will be restated for you there. Let me give you a quick summary. It's

Keck hexagons divided by JWST hexagons plus Palomar hail divided by Mount Wilson Hooker telescope diameters. See, it's simple. Oh, and make sure you follow standard mathematical order of operations. Ah, see, I was going to, you didn't mention any parentheses. So yeah. Okay. I'm glad you added that. Okay. Just making sure. You got until the 19th. That'd be January 19th at 8 a.m. Pacific time to get us the answer to this one. Get out your calculators, everybody. And our winner will get, and this is such a great way to celebrate the successful deployment of JWST. We're going to send you a tie, a beautiful gold on black tie from our friends at Startorialist. I have one of their ties.

I got it for our planet fest. It's Perseverance with Ingenuity, the helicopter up on top. This one is equally pretty and handsome. We wish you luck. Can you wear it as a scarf or a brooch or a pterodactyl? A pterodactyl. Sure. Why not? Just a little origami pterodactyl out of that. All right. Cool. No, that's nice. I like that. All right. We done? We're done. All right, everybody. Go out there, look up at the night sky, and think about oatmeal. Thank you, and good night. Yeah, I love it.

With some blueberries, frozen blueberries. Thank you. Now I know what I'm having for lunch. He's Bruce Betts. He is the chief scientist for the Planetary Society, who joins us every week here for What's Up. One more pitch to help us out by completing the Planetary Radio Listener Survey at planetary.org slash survey.

We want to know how you feel about the show and what you'd like to hear more of. Planetary Radio is produced by the Planetary Society in Pasadena, California, and is made possible by its members. Mark Hilverda and Jason Davis and our associate producers, Josh Doyle, composed our theme, which is arranged and performed by Peter Schlosser at Astro.