Chasing auroras with the Aurora Guy

Sarah Al-Ahmed: We are talking auroras this week on Planetary Radio. I'm Sarah Al-Ahmed of The Planetary Society, with more of the human adventure across our solar system and beyond. I don't know if you've noticed but our star has been acting up in recent months, and that's totally to be expected. We're near solar maximum, a time in the solar cycle when the Sun is most active. That means more sunspots, some coronal mass ejections and auroras on worlds all across our solar system. This week Vince Ledvina, also known as The Aurora Guy, joins us to discuss the science behind the Northern and Southern lights, and what that can tell us about our Sun, our planet and all of the worlds across the galaxy. Then Bruce Betts joins me for What's up? A chat about global magnetic fields on terrestrial worlds, and a new random space fact. If you love Planetary Radio and want to stay informed about the latest space discoveries make sure you hit that subscribe button on your favorite podcasting platform. By subscribing you'll never miss an episode filled with new and awe-inspiring ways to know the cosmos and our place within it. Before we move on to our interview today I'd like to give a huge congratulations to the team working on the Boeing Starliner. We've been covering the tale of the Boeing Starliner astronauts, Sunita Williams and Butch Wilmore for the past few months. These two brave space travelers are now on an extended stay aboard the International Space Station, following the first crewed test flight of the Boeing Starliner. It had some issues during the launch and they wanted to make sure it was safe for everyone. Suni and Butch are going to remain on the Space Station until early 2025, and on September 6th, 2024 the spacecraft returned safely to earth without its crew. There's still a lot more work to be done, but that's great news. Congratulations to the team for what I'm sure was a very stressful but also triumphant touchdown. And now for some auroral science. Today we're joined by Vincent Ledvina, a professional Aurora Chaser and photographer, also known as The Aurora Guy. Vince captures beautiful images and video of the Northern Lights from his home base at the University of Alaska Fairbanks, where he's a Ph.D. student. He works to share the science and the beauty of auroras with people all over the world. The Aurora Borealis and the Aurora Australis, also known as the Northern and Southern Lights, are formed when charged particles from our Sun are guided by the Earth's global magnetic field toward its poles. These charged particles interact with the gas in our atmosphere and cause it to glow. The aurora are a beautiful indicator of the deep connection between our star and all of the worlds that orbit it. In this conversation you'll hear Vince and me discuss an aurora-like phenomenon called STEVE, which stands for Strong Thermal Emission Velocity Enhancements. They sometimes accompany the aurora, but they're a distinct phenomenon and their name has an adorable origin. It began with a Canadian citizen science group called the Alberta Aurora Chasers. They named these lights STEVE in an homage to the animated film Over the Hedge. There's a scene in that movie where the characters name a hedge Steve to make it seem less scary, which is perfect for a mysterious phenomenon like STEVE. We'll also bring up the GOES Earth Observing Satellites. GOES stands for Geostationary Operational Environmental Satellites. The GOES satellites are operated by the United States National Oceanic and Atmospheric Administration, or NOAA. They're used for all kinds of things, including weather forecasts and storm tracking. I highly recommend everyone check out the images and data from the GOES satellites. Watching Earth's weather patterns from a location in geostationary orbit is really impactful, at least for me, and I check it any time there's a major storm in the United States. Humanity has observed auroras on many worlds in our solar system. By studying these beautiful lights on earth Vince and other Aurora Chasers are helping to bridge the gap between solar science, space weather and our observations of all of the other worlds orbiting stars. Hey, Vince, thanks for joining me.

Vincent Ledvina: Hey, thanks for having me.

Sarah Al-Ahmed: I've been privileged to see so many cool space things in my life, but I tell you to this day I've never been able to see the Northern or Southern Lights, so I'm really jealous, actually. That's awesome.

Vincent Ledvina: Yeah, they're pretty incredible. You have to see it at least once in your life.

Sarah Al-Ahmed: Right. But thankfully I have people like you on social media and other platforms that do the work of taking the images and the video and putting it out online, and there's been more than once I've looked at your feed and just literally shouted, wow, at my computer.

Vincent Ledvina: Yeah, the auroras are just awesome. I'm honestly obsessed. They're just so beautiful. Every single night is something different and just surprising. So yeah, I've seen the auroras hundreds of times, but they always just make me happy.

Sarah Al-Ahmed: That's an interesting point about it. There's some phenomenon that you can only really capture in the moment. Every total solar eclipse is different, every aurora is different, and being there in that moment is a unique and particular experience that you just have to enjoy in the moment, and can't really be conveyed to others. You can try with photography and video, and you do very well, but I bet it's one of those things that's totally different, very moving experience in person.

Vincent Ledvina: Oh, yeah, I completely agree. Photos, especially just photos, only give you that one snapshot in time. Videos at least let you see the motion of the aurora. But you just never, at least I can never pan my camera around fast enough to capture what's usually a 360 degree aurora display in the sky. I think the main thing to realize is that when you're there the auroras are surrounding you. It's almost like this enveloping experience, almost like you're in a planetarium or something, that you just cannot replicate or get the feel of with a photo or just a video.

Sarah Al-Ahmed: Your origin story goes all the way back to when you were a child, when you experienced the Halloween storm aurora in 2003.

Vincent Ledvina: Yes, yeah.

Sarah Al-Ahmed: What was that, and how did it impact your life path?

Vincent Ledvina: Yeah, so for those of you who are not familiar with the Halloween storm, they occurred on October 29th to 31st 2003, roughly around Halloween, about 20 years ago. So actually just this year we saw the largest geologic storm since those Halloween storms in 2003. So it's a really big event, one of the largest in modern history, and auroras were seen as far south as the Southern United States like Alabama, Texas, New Mexico. I grew up in central Minnesota, in the Twin Cities, so I was only four years old, so granted I wasn't super, I guess, conscious of what was going on. But I remember coming home from trick or treating and seeing these streamers in the sky. It almost looked like searchlights or something just moving around the sky super fast. And our house at the time had these windows that faced west and had a nice view of the horizon, and I remember just walking in with all my candy and looking out over those windows over the Mississippi River Valley and just seeing these aurora just dancing all over the place, these pillars. And my parents didn't know what they were, but I remember the next day we found out that it actually was the aurora. So of course I didn't go out and pick up a physics textbook the next day, I was only four years old, but I do think that that experience really shaped my life moving forward. I mean, I went into Boy Scouts. I was a huge fan of the outdoors. I went camping all the time. I was obsessed with space. I wanted to be an astronaut, like every kid. But I was crazy, I would read textbooks and instead of being into video games I was into Morgan Freeman documentaries and Cosmos. So yeah, I was just obsessed with space, and also with the night sky. And then one thing led to another and in high school I picked up photography, specifically astrophotography. And then the ultimate, I don't know, this is my opinion, but the ultimate form of astrophotography is aurora photography. The Milky Way doesn't change. It stays pretty much in the same part of the sky every night, so you can develop a plan and you can really figure out what you want to do with your Milky Way photography. You can figure out where you want to be, which direction your camera should be pointing, dial in all your settings, and you basically have the shot ahead of time. You don't have to do a whole lot of work. But with aurora photography there's a lot more planning involved. So it was a challenge that I wanted to give myself is how to actually catch these Northern lights, because down in Minnesota we would get them, but it was solar minimum, so there wasn't as much space for their activity. So maybe once a month you would get a little fleeting display on the northern horizon. And I was growing up in the suburbs of the Twin Cities, so a lot of light pollution, so took a lot of planning, but I got really just passionate about auroras, about space weather. I found out that space weather impacts technology in the daily lives of people and humans in outer space, astronauts and aircraft, high frequency communications. So I got really into the science as well. And then now I'm just up here in Alaska, fully embracing the aurora life, going to school to study it, and also aurora chasing as much as I can up here at Fairbanks.

Sarah Al-Ahmed: And you graduated from the University of North Dakota about two years ago, right?

Vincent Ledvina: Right, yeah.

Sarah Al-Ahmed: And during that time you got to do some undergraduate research that actually pertained to this. What did you do?

Vincent Ledvina: Yeah, so UND was a great place for me to go to school because it was far enough north where I could see the aurora quite a bit more frequently than down in the Twin Cities. And I actually wanted to move to Fairbanks when I was 18, going to college, but my parents said that was too far away. They wanted to be within at least a five-hour drive of seeing me. So I said, okay, fine, I'll settle with North Dakota. And Grand Forks, that's where UND is at, there's a lot of dark skies around UND so it was a great place to do aurora chasing, and I really cut my teeth on aurora photography and forecasting, more or less, space weather and the aurora, and then also teaching others just in the local community. I was a president of our astronomy club at UND so I would give talks all the time about space weather and share what I had learned recently, or I would do some research on my own and then just bring that to the class. But yeah, when I was at UND there was no space physics program there, unlike here at UAF where it's been a staple for the past 60 years. At UND a lot of the professors focused on either supernova or solar safe physics. So there was no space physics, no auroral physics up there so I had to seek out my own opportunities. I did a research experience for undergraduates after my freshman year, and that was at the National Solar Observatory, so I got my feet wet with space weather, but it was very close to the Sun. I was doing very small scale physics on the solar surface, so not auroras, but I was just happy to do something related to space weather. And then that next year I interned for a NASA citizen science project called Aurorasaurus, and with Aurorasaurus I helped found an aurora camera project at UND. So it was a partnership between the University of North Dakota, Aurorasaurus and a commercial live-streaming service, called the Live Aurora Network. We set up this aurora webcam, which was a tool for other Aurora Chasers to use, to understand what kind of conditions were being seen around the Grand Forks area. And then those images also would be made available and open for science. So the benefit of having a camera at the mid-latitude zone is that even though you don't get auroras all the time you get to see these rare auroral phenomena, like STEVE, if anyone's familiar with STEVE.

Sarah Al-Ahmed: The STEVEs.

Vincent Ledvina: Yeah, the STEVEs.

Sarah Al-Ahmed: I remember when they named those. They were great.

Vincent Ledvina: Yeah. Yeah, Strong Thermal Emission Velocity Enhancement. And the fun fact about that is it's actually called a backronym, so not an acronym but a backronym, because STEVE came before the science terms were added to each letter. So NODAC was the North Dakota Dual Aurora camera. That project is still alive and well, so I'm happy to see it's continuing even though I've left UND. But really the transformative experience for me was when I went up to Alaska my senior year and helped out with sounding rocket launch. So it was very spur of the moment and just they needed a "grad student". And there weren't any grad students available or willing to go up to Fort Yukon, Alaska, and stay at an Air Force base for three weeks. I don't know, to me that sounds like a perfect, perfect time, but I guess some people don't want to spend three weeks in the middle of nowhere without any cell service or internet. So anyways, the burden eventually fell into me, or rather the question of whether I wanted to go up to Alaska. It was on a Tuesday that I got this email, and on Friday I was on a plane up to Fairbanks. So I spent three weeks up there in Fort Yukon helping with ground operations for the sounding rocket. So I didn't actually help out with the rocket assembly or rocket integration, but I took images of the aurora through which the rocket flew. So I was up there for three weeks and I saw the first high latitude aurora of my life, the first real aurora. Because down in North Dakota, Minnesota, those auroras are awesome, but they just don't compare to what you can get up in Alaska. I mean, these are so much brighter. They move, and they're right above your head. I mean, they almost look 3D, and they look like they're coming down and trying to touch you. It's just a crazy feeling. So I was up there, and I was up there for three weeks and just had a magical time, and that's really what drove me to move up to Alaska and pursue a PhD. So yeah, those experiences really shaped my life.

Sarah Al-Ahmed: That sounds like a beautiful experience. The closest I can ever come to is watching the videos online. And particularly, looking at the videos that the astronauts shoot from the International Space Station as they're going over the earth, just the shifting lights. And I've gone through and tried to find VR experiences to try to get that feeling, but being up in it, that's got to be something completely different after dedicating so much of your life to loving this thing already.

Vincent Ledvina: Yeah, it was very, very vindicating, very satisfying to be up in Alaska and see that. I'd been down in Minnesota and North Dakota for most of my life, and I had seen the aurora from those places and it looked great. I was always just thrilled every single time I would go out. I was constantly checking off, oh, I've just seen the best Northern lights in my life because it just kept getting better and better. As we were heading into solar max we kept getting more geomagnetic storms. But then when I went up to Alaska, I was like, okay, wow, it really does get better. And even the best aurora I've seen, which was last year in March, I have friends who've been up here for 20, 30 years and they were like, "Oh, that was pretty good." So the fact that I know that there's better is what also keeps me going. It's like I still haven't seen the best of it, and that's according to all these locals who've been up here for just decades. So it was a pretty awesome experience.

Sarah Al-Ahmed: I know you're just starting out on your PhD, but do you have any idea what you're going to be dedicating your main research to?

Vincent Ledvina: Oh, yeah. Yeah. So I was lucky enough to receive a fellowship actually. I applied after I finished undergrad and I got this fellowship to pursue research right away. So usually you have a TAship and then you can go into your RA after you pass your exams and pass your prospectus exam. But luckily I'm already starting on research. So I have two topics for my PhD, which are related, but the first topic is on auroral beads. So for those who are not familiar with auroral beads, and I'm going to try and keep this short, but essentially you can get these auroral arcs that span across the sky going from east to west. They look like little ribbons, and this signifies a growth phase in the aurora. So the aurora is charging up when you see these really thin skinny arcs stretching across the sky from east to west. And usually when I'm talking about all this I'm talking about up in Alaska or any other high latitude place where you can actually see the aurora overhead. This looks a lot different when you're down in places like Minnesota or North Dakota where you're seeing the aurora edge on. But when you're underneath the aurora you see these thin arcs, and that's when the aurora is charging up, and then all of a sudden over the course of one to two minutes these little thin arcs can form beaded structures along them, literally looking like a necklace, like a pearl necklace. You get these little spheres or lumps of aurora, called auroral beads, and they start out from nothing and grow very, very large and very, very bright over the course of one or two minutes. And scientifically that's really interesting because the fact that it's growing exponentially means that there's some sort of instability in outer space that's triggering these auroral beads to form. And they're periodically spaced, which gives us a clue as to what sort of plasma processes are causing these beads. And right after these beads form, you get what's called the expansion phase of the aurora, which is what everyone wants to see. It's when the aurora just goes nuts, is moving all across the sky, it expands from north to south. You get streamers that are just moving around so fast you can barely track them, and that usually lasts for 15 to 30 minutes. So these beads, these really short-lived structures in the aurora, are somehow linked to this explosive release of energy. So that's what I'm trying to figure out is what's causing these beads. And then using citizen science data we can also look at beads. So that's my other half of my thesis is looking at how Aurora Chasers and the public can actually provide data to help researchers do real science. I think that's something that most people don't realize is that with auroras a lot of the science that we do is based on analyzing images. While there are great scientific imagers and all these networks of calibrated imagers across Canada, Alaska and Northern Europe, when these auroras move further equatorward, out of the field of view of these high latitude imagers, they're basically placed up there because you get auroras all the time. So if you're a scientist with grand dollars you want your highest return on investment, basically. So if you're looking at the aurora, 90% of the time it's going to be in Alaska, but when it moves outside of Alaska or these high latitude areas, that's actually when we get some of the coolest features and the strangest things going on. And Aurora Chasers are the ones who are capturing those auroras. So in order to study these weird rare auroral phenomena or auroral-like phenomena, like STEVE, SAR Arcs, all these things, we have to rely on Aurora Chasers' images. So that's my other half of my thesis.

Sarah Al-Ahmed: Well, I mean, people all over the world have been seeing more and more of these auroral phenomenon at latitudes that are closer to the equator because of all these solar storms. Do you have any recommendations for where they can go online to contribute their imagery if they capture anything?

Vincent Ledvina: Yeah, yeah, for sure. So aurorasaurus.org. I interned for Aurorasaurus in 2020, and they're great. Aurorasaurus is a platform that basically helps you see the aurora more precisely, or it gives you a better idea of where the aurora is being seen, and it does that by user reports. So you can look at space weather data, like solar wind, for example. You can get all these fancy plots with density and speed and temperature of all these particles, or you can look at wiggles of a magnetometer, but really to help answer the question is the aurora out, you just want to know what other people are seeing. So you can go to aurorasaurus.org and you can say, "Yes, I've seen the Aurora." And you basically are reporting this in real time. You can also go back and report it retroactively. You can say, "Yes, I've seen the Aurora." Hit yes, and make a report. Or you can say, "No, I'm not seeing the aurora." And why, If it's cloudy or maybe there's just no activity. But these reports get placed on a map along with models of the aurora. And during geomagnetic storms especially, it's really helpful to see where other people are seeing the aurora because the models don't do a great job. So Aurorasaurus provides a really good ground truth what is the aurora really doing picture? And besides that function of the project you can also upload your images, and those get put into a database that scientists can access. And those images then are made open for research, and with all the right privacy standards and with respect for the photographers. It isn't like your images are just being thrown up there and anybody can download them at full resolution. There are stringent restrictions on this. But you can submit your images, you can submit videos, time lapses, and a lot of research results have come from that. Aurorasaurus was involved with the first paper on STEVE, characterizing the different times at which it's seen, where it's being seen. It was a direct collaboration between Aurorasaurus researchers and Aurora Chasers. So yeah, if people are out seeing auroras at mid-latitudes or in weird places, or they see something weird in the sky, go submit your reports to Aurorasaurus.

Sarah Al-Ahmed: I think this is really cool about this is that it not only allows us to understand more of the beauty of these auroras, but this is like the stepping stone between what we know about solar weather, how it impacts the earth, and then what we see on other worlds, because we've seen aurora on places like Mars and Jupiter. Have you had to use any of that data, or have you been interested in looking into what they're doing on other worlds?

Vincent Ledvina: Yeah, so that's actually really cool. So I was just at this Heliophysics Summer School in Boulder, Colorado, a few weeks ago. We had entire lectures on auroras at Jupiter and Saturn. There's aurora on moons as well. Basically any world that has an intrinsic magnetic field and a nearby star should have aurora. Oh, it also needs an atmosphere too, I forgot about that. Needs an atmosphere, an intrinsic magnetic field and some sort of solar wind ideally. So Mars has auroras. Earth obviously has auroras. I think Mercury also might have some auroras, although I'm not sure about the atmosphere. But yeah, I mean there's a whole group here at my university who does research onto Jupiter's auroras. What's really interesting is Earth is relatively simple. We just have an intrinsic magnetic field that creates a magnetosphere, solar interactions, whatever. But some of these other planets have moons that are spitting off tons of weird chemicals into the near planetary space environment, so like Jupiter, for example. EO, the moon EO, is super geologically active. So there's volcanoes on a surface that are spitting out all sorts of chemicals and weird things in a space. So you basically get this huge donut of volcanic material surrounding Jupiter, which can cause some weird patterns in the aurora. You can actually see in images of the aurora on Jupiter there's little foot points corresponding to all the moons. So it's just really cool how auroras interact with different planets. But I think I've even heard that you can potentially detect auroras on exoplanets, which could really change the game, I think, for determining what exoplanets are habitable, because if you know that an exoplanet has a magnetic field, well that can help keep the atmosphere intact too. Mars does not have a magnetic field. I think somehow the core turned off, the molten solid core which we have at Earth, which creates our dynamo and magnetic field, that somehow turned off at Mars and its atmosphere gradually became stripped. So if you see an exoplanet with an aurora, well, it's pretty good chance that you have a magnetic field there, so that could have some impact on habitability, I would think. So, yeah, it's really cool. I mean, auroras are not just relevant for earth and space weather here, but can tell you all sorts of different things about planets in our own solar system, and even exoplanets apparently.

Sarah Al-Ahmed: That's a really great point. I never even considered using that as a marker of potential habitability, but that actually seems like a really, really powerful tool. I mean, not just for understanding the world itself, but also what's going on with space weather in that system, because that as well could potentially affect whether or not a world could have life on it. If a star's too feisty you're going to be in trouble.

Vincent Ledvina: Right. Yeah, that's the thing. Yeah. Space weather around exoplanets can totally kill any hopes of life. If you have a really active star it could completely strip out the atmosphere of an exoplanet and create some potentially bad situations for life, potential life on the surface.

Sarah Al-Ahmed: And even here on earth the Sun hasn't pulled a full Carrington Event in quite a while. But, I mean, as we grow more and more technologically advanced we really need to think about this, because it deeply impacts all of our instruments in our entire infrastructure. We have to worry about this, but thankfully, we have a whole slew of scientific instruments that are now monitoring the Sun. And I was really glad to read online that you've been using some of these instruments, particularly some of the GOES magnetometers to help you understand and predict some of these aurora phenomenon. How does that work? Why is that so powerful?

Vincent Ledvina: Yeah. So I guess just to provide some context, there's a lot of different tools that we can use to forecast space weather and forecast the aurora. There are magnetometers and plasma instruments in outer space beyond Earth's magnetic environment that are in the pristine solar wind. So they're actually placed at a Lagrange point, L1. So that's just a gravitationally stable parking area for satellites. So there's spacecraft, like ACE or Discover or Wind. These are all names of spacecraft that are monitoring the solar wind. So that can give us of the density, the temperature of the solar wind, the speed. So basically if you think of space rather as this wind that's blowing off the Sun, essentially how fast and how strong is that wind that's coming at Earth, it's those kind of measurements. And then we don't really have anything from that point to Earth's magnetosphere. Things probably don't change within just 1 million miles, but once that hits our magnetosphere there's tons of different processes that happen. Some of that energy from the solar wind gets transferred down, basically penetrates our protective magnetic bubble, and we can then measure changes on the ground. When those particles funnel in over the poles and create the aurora there's currents that gets set up. We can measure those with ground magnetometers. We can also measure the shape of the magnetosphere and basically how stretched out it gets. So this is where the GOES magnetometers come in. So when these particles from the solar wind, the breeze hits our planet. Just like a rock in a stream of water, the water gets diverted around the rock and forms this teardrop shape. The same thing happens with our own magnetosphere. So earth is a dipole magnetic field. So if you've ever done the experiment where you put iron filings on a sheet of paper, you can see those magnetic field lines wrapping around. Well, Earth's magnetic field looks like that, but because the pressure of the solar wind pushes back the magnetosphere, we get this thing called a magnetotail that develops. So it can stretch for many tens or even a hundred earth radii downstream of the solar wind on the night side. So when that tail stretching happens it basically means that all these particles are being held in the magnetotail, and that's when you get the aurora charging up. So when these particles hit our magnetosphere they get convected back towards the magnetotail. They get held. You can almost think of it as filling a bucket with these aurora particles, and then all of a sudden that bucket gets filled and it tips over, and then you get this huge substorm, which links back to the expansion phase I was talking about earlier, where the aurora goes nuts. It's just a very explosive release of energy, and you can detect the shape of the magnetosphere with magnetometers. So the GOES magnetometer basically shows you how stretched out the magnetotail is. So if it's more stretched out that means the aurora is getting more charged up. And then as soon as that rubber band, basically imagine that you're pulling back a rubber band and it's getting shorter and shorter, it's getting fatter while it's getting more stretched out. If you actually look at the graph of GOES you can see the plot going down. And the plot tells you how tall, basically how tall the magnetosphere is. So if it's really fat and squished, that means it's really stretched out. So as soon as those particles get released in the tail that bucket tips over. All the particles then slingshot back and form this expansion phase aurora. That graph shoots up because now all of a sudden you're going from a more stretched magnetosphere to more, it's called dipolar. So now it's more looking like what you would expect for a bar magnet. It's not super stretched out, it's a taller Y component or taller orientation. But yeah, you can see these what are called dipolarizations, these big spikes in the GOES magnetometers, which correlate almost perfectly with big bursts of aurora. So yeah, these GOES magnetometers, I don't think people are really using them in the Aurora Chasing community. And then I had friends that were coming up here for a rocket campaign, and they were up in Fairbanks so I went to Poker Flat with them one night. I was just chatting, and they had a GOES magnetometer pulled up on one of the monitors in the space sciences building. And I'm like, "Oh, why are you using that?" And they're like, "Oh, well, we're going to try and time the substorm with the rocket launch." And I was like, "Oh, you can do that?" And then of course they explained it to me and it made total sense. So now that's really all I use up here in Fairbanks is the GOES magnetometer. I mean, all the other measurements are helpful, but to some extent they're just proxies for really what's going on around earth. So these GOES magnetometers it's a little bit of an advanced concept, but as soon as you understand the rubber band analogy and the bucket and substorms and how everything works, it starts to make a little bit more sense, I think.

Sarah Al-Ahmed: I'm so impressed with those satellites. I mean, the number of people whose lives have been literally saved by their weather monitoring systems is one thing.

Vincent Ledvina: Oh, right. Yeah.

Sarah Al-Ahmed: But it never even occurred to me that you could use GOES to help you track aurora. That is such a cool idea. And also occurs to me that it is supremely lucky that you, as someone who's so passionate about this, just happens to be coming into grad school right around solar maxima, right? That is a perfect trajectory, a perfect arc there. How has the last few months been for you, since we've been seeing all kinds of solar storms and all kinds of wacky things going on?

Vincent Ledvina: Yeah, I mean, it's been a lot. I've gotten a lot of messages, for sure. People are just really excited. I don't want to say I timed this perfectly, but it feels like I did, getting into Aurora Chasing during solar minimum. But I feel like that really taught me how to chase auroras, because nowadays there's so much activity you could pretty much just go outside and see something wherever you are. It's just nuts. But yeah, I mean, people are excited. I've been just inundated with messages, especially during the May storm. I think I got almost a thousand emails, a thousand messages on social media, and people were just so excited to finally see the aurora for the first time. I don't think that people were expecting the Northern Lights to be seen from as far south as Mexico or Puerto Rico, or even Morocco. All these places that nobody expected to see the Northern Lights, or even the Southern lights were finally accessible. So I think we had a lot of people who were planning trips to Alaska or planning trips to Iceland and then they saw the aurora. They saw the Aurora in their own backyards, and they were like, "Okay, well, here it is." It's a pretty cool experience. So yeah, the Sun's really active. It's the most active it's been in some respects since the early 2000s, so it's a great time to be in Aurora Chaser. I keep saying that to people, but it really is true. I mean, the data supported it, it's not just saying it for a marketing slogan, it really is. We've had the most extreme space weather since 2003 really, if you look at the May storm. And there's CMEs, all these big explosions off the Sun, they're happening multiple times a day. Sometimes they're directed at Earth, so they're happening so often that it's hard to even track them. I mean, you'll get a surprise impact at Earth it seems like every few days. And the auroras up here in Alaska have just been great. Every single night we've had a good show, so it's been awesome.

Sarah Al-Ahmed: We'll be right back with the rest of my interview with Vince Ledvina, The Aurora Guy, after the short break.

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Sarah Al-Ahmed: Most of the images that we see of aurora online are this vibrant green color, and I've seen a lot of questions online because of this experience that people have had during the solar maximum about the different colorations we see in the aurora. What is that different, the red color aurora and the green color aurora, what does that tell us about what's going on with space weather?

Vincent Ledvina: So the color of the aurora, I always like to say that the aurora is like a giant neon lamp in the sky. So instead of electricity coming from a wall outlet, like in the case of a neon lamp energizing neon gas in a tube, you have electricity coming from outer space, energizing Nitrogen and Oxygen Plasma in the upper atmosphere. So the green emissions are the most common. They're formed by O+, and that's usually around 100 kilometers in altitude. And then the reds are the same Oxygen, but it's just at a higher altitude. And then you can get this whitish/pinkish fringe underneath the green, that's formed by Diatomic Nitrogen, N2. And then you can get blue aurora actually from N2+. And that blue aurora is pretty rare because it usually hangs out around the green layer, but the green layer is just so bright that it overpowers the blue. But when you have enough particles coming in, usually during a geomagnetic storm or some other large event, even during a sub storm, so these could happen every night, but relatively they're rare colors, these blue colors. The analogy I like to give is if you throw a big stone into a lake or into some sort of body of water, that first impact, you can see a big stream of water shooting up into the air. So it's the same thing with these blue aurora particles is that when you have a bunch of particles dumping in from outer space it causes these N2+ molecules to lift up to higher altitudes. And when they're at the altitudes of the red Oxygen, the red cannot overpower the blue so then you can see the blue. So you can usually get mixing of these colors and get all sorts of different combinations, like orange. You can get purple and pink. That's when the blues and the reds are mixing at the top. And the types of aurora colors really tell you the energy of the particles coming in. So these particles coming in from outer space they have a certain energy, and luckily they don't hit the ground. They basically run into gas as they're coming in. So they have to stop at some point because the atmosphere gets thick enough. But if they have a higher energy they'll penetrate further and they'll hit more particles on the way down. So when you get that lower pink/white fringe on the bottom of the green, that's sometimes called the Nitrogen fringe. That usually only happens during sub storms when the particles are super high energy. But the red aurora is usually caused by very low energy particles because they don't have enough energy to make it down to hit that green layer. So during the May event, actually, we had lot of red aurora. Basically almost 100% red in some instances, which means that there were a lot of particles coming in, but they were all very low energy so they weren't making it down across the green. They were just being deposited in that upper red layer. So the type of aurora, the shapes too, also tell you different things about the energies as well. That's a little bit more complicated, but yeah, aurora colors on camera and also to the eye look very different.

Sarah Al-Ahmed: Yeah. I'm curious because I've always wanted to see this in person. But I know how the human eye works and what happens when you descend into darkness, so I'm imagining that you're probably less likely to be able to see those colors in such a vivid nature.

Vincent Ledvina: Yeah, exactly. So just like you said, the human eye and cameras work a lot differently. So cameras have pixels which can see individual photons and their wavelengths, so you can get really, really weak greens showing up on your camera. But our eyes don't have pixels. We have rods and cones, which are the photosensitive cells at the back of our eyes. So rods are responsible for our night vision. They see very well in dim conditions, but they only give us gray scale vision and they don't see details very well. So when you're looking at the aurora, if it's not very bright you're likely not to see any colors at all. And it's also true just at night in general, a lot of people don't notice, but you really only see in black and white if you're in a really dim lit area. When the aurora gets bright enough however, you can start to activate your cones. So your cones take a little bit of light to activate, and the cones are what give you your color vision and also allow you to see more details. So obviously when you're walking around in sunlight, in the everyday lit scenario, your cones are always active so you never really notice them turning on or off. But when the aurora gets bright enough it starts to activate your cones and you can see the colors a little bit better. So your camera can always see the greens, always see the reds, but to see them with your eyes you need a really bright aurora. Or, and this is sort of a little known fact, is if you have a little bit of ambient light in the sky, like a moon, or even light pollution, or a street lamp or something, there's also a little trick where you can, and this is counterintuitive to viewing dim objects at night, but if you look into a flashlight when you're aurora chasing and then quickly look away to the night sky, that flashlight, obviously it's really bright light, it's going to activate your cones all at once. Then your cones take a little bit of time to deactivate. So if you quickly look away you can see the green in the aurora before your night vision kicks in. So it's a little trick. But yeah, chasing auroras under a full moon, that added ambient light is activating your cones and you can see even green colors in dim auroras, I found. So there's a lot of nuance to the differences between cameras and eyes and how they work and how color in the aurora can be perceived. But yeah, there's a little tricks that you can use to accentuate your experience.

Sarah Al-Ahmed: This brings a question to mind that I have wondered for months, because we had a total solar eclipse earlier this year, and the next solar eclipse on earth goes through Greenland and Iceland in August 2026. So imagine this, in that moment we're near solar maximum, you've got the light of day right up until totality hits. Suddenly everything drops into darkness. It's hard to know whether or not we'll be lucky enough to have a lot of aurora at that time. But what do you think are the odds that people who are observing that eclipse might be able to see both the totality and the aurora at the same time?

Vincent Ledvina: Yeah, I've gotten this question before, and actually I talked to some scientists about it because we were all at a conference and wondering the same thing. Unfortunately, I think it's about 0%, which is not the answer that I think most people want.

Sarah Al-Ahmed: Oh, no.

Vincent Ledvina: But yeah, I mean there was a total solar eclipse in Svalbard, I forget when, but it was in the last 20 years or so, or even 10 years I think. So there's two things, right? Auroras at the auroral oval latitudes are usually only seen at night, so during the nighttime hours, I should say. So in Alaska, Fairbanks I should say, even though it's dark for almost 20 hours during the solstice we only see auroras still during the nighttime hours. So still really only from 10:00 PM to 4:00 AM. And it's the same in places like Iceland. It's the same in places like Greenland. Now, if you go further north, actually north of the auroral oval, you can get auroras during the daytime. So Svalbard, for example, sees auroras almost 24/7, and this is due to something called the cusp aurora. So at those latitudes the field lines that are coming out of the ground are actually connected directly to the solar wind. So it's just a weird quirk where you can get auroras during the daytime hours at really, really high latitudes in the polar cusp. So in Svalbard, when they had a total solar eclipse, that was basically the only place where you could get auroras because it was high enough in latitude where you could get auroras during the daytime, and they didn't see anything. And even worse is that there was actually some active geological conditions at the time. So all the conditions were set up, unfortunately in Svalbard for there to be auroras. During a total solar eclipse they didn't see anything. I don't want to say it's impossible, but it is almost impossible to get auroras during the daytime. We're just not far enough north. So unfortunately, the chances are very low, I think, for the next solar eclipse. Although I think there is one, I'm going to not get the year right, I think 2034 in Northern Alaska, and the very, very far northern regions of Alaska do get this cusp aurora, that places like Svalbard gets. So I mean, if you're trying to get auroras during a total solar eclipse I think that's the one to go to is this 2034 eclipse. But yeah, and also, I don't think it even gets dark enough, a total solar eclipse. I saw the one in April, it was amazing, but it did get dark, but actually not as dark as I was expecting. I was expecting to see a lot more stars, and I could see some planets and things like that, but I just don't think it's dark enough to see the aurora. Living up here in Alaska I know how dark it needs to be in the sky to see the aurora. And even in the summer when the Sun goes below the horizon, we don't get midnight Sun here in Fairbanks, the auroras don't come out until mid-August and they stop in late April. So in those scenarios you still have stars in the sky. It's about as dark as a total solar eclipse. So I don't think it can ever get dark enough, honestly, to see the aurora. Yeah, it's a bummer.

Sarah Al-Ahmed: I mean, as sad as that is I'm just glad to have the answer because I've been wondering for months. So thank you, that solves it. So for anybody who wants to try to begin on this trajectory that you've committed your life to, what would you say are your top tips and tricks for actually trying to capture this on video or on camera?

Vincent Ledvina: I would say there's really two philosophies to aurora chasing. There's a philosophy of planning a trip to the auroral oval. So the auroral oval you can see the aurora, every single night it's dark and clear. So up here in Fairbanks we get aurora every single night. It needs to be clear because auroras take place so high up in the atmosphere that any clouds will block your view, and it needs to be dark. So no time in the summer would work. But you can either travel to see the aurora, in which case you just need to pick a week, basically any week during aurora chasing season. So roughly from mid to late August to mid to late April, aurora chasing season in the Arctic. It varies by one or two weeks, depending on where you want to go, and the latitude of that location. But yeah, just pick a week and just head up there with your camera. If you're there for a week you should have at least one clear night, knock on wood. I went to Iceland once and it was cloudy for six nights in a row, but that's pretty unusual. It's probably just unlucky. But yeah, if you're in Fairbanks, Fairbanks has pretty good weather, actually. Norway has, at least near the coast, it's pretty temperamental, so. March is usually a really good time though, at least in Fairbanks as well as other Arctic locations. September too, September and October are usually pretty good. So yeah, the fall and the spring months are good for weather and lack of cloud cover. They're also a little bit better in terms of auroral activity. There's something called the Russell-McPherron Effect, which actually doesn't have a very solid scientific explanation as to why this happens. But you basically get more of these bursts of aurora, these sub storms, during the months of September in March. So if you can try to plan your aurora chasing vacation for a week in September, or a week in March or early April, that's the best plan. The other philosophy is just to see it from your own backyard, and in that case you have to rely on space weather to give you those gusts of solar wind, really enhanced conditions so we get more energy being pumped into the aurora ovals, which can cause them to expand. So obviously the May event is a really good example, but that was a pretty severe solar storm. But yeah, even minor storms you can see the aurora from the U.S. Canada border for example, or Central Europe, but that requires you to pay attention to what's happening. So in that case I would just look at your local space, local meaning your national space weather office if we have any global listeners here. Obviously the NOAA Space Weather Prediction Center in the U.S. is the one to watch, but there's space weather offices all across the world now. People are realizing the impact space weather has. So there's space weather offices in the U.K., in Austria, in Belgium, South Africa, Korea now has one. So watch your space weather office and what they're posting. If there's a solar storm headed our way I know NOAA Space Weather Prediction Center for sure will put out a bulletin and an alert saying hey. Let's say it's Monday, usually you have a one to three days heads up. Let's say it's Monday night and you're checking and it says Wednesday night there's a good chance that we're going to get hit by this coronal mass ejection, this big solar storm. Wednesday night comes and you should be checking webcams, Aurorasaurus, social media for what other people are seeing in your area, obviously checking cloud cover too, trying to find a place that's a little bit less life polluted. So life pollution runs on a Bortle scale, so Bortle meaning the quality of your sky. So 1 is the highest quality night sky, no light pollution, and 9 is like an inner city, so very light polluted. You don't want to be in a 9. You want to be somewhere like a 3 to a 5 at the bare minimum to see the aurora. And try and not have any large population centers placed between you and the pole. So for us in the Northern Hemisphere, let's say that you live in the Twin Cities, well, you don't want to go south to Rochester, Minnesota, for example, because you're going to be looking right into the Twin Cities and that huge light pollution bubble. So make sure that you're heading north. Or if you're in the Southern Hemisphere, south of wherever your population center is, or this light pollution bubble where you live may be. So, yeah, I mean, a lot of it is just down to timing of the aurora. Watching the GOES magnetometers for these substorms too is really important. And GOES really only works for the North American sector because their geostationary satellites placed both on the east and the west coast of the U.S. So unfortunately, if you're in Europe you might have to rely on something else. You can use ground magnetometers, but webcams work too, just to understand how the aurora is playing out and what conditions are looking like on a specific night.

Sarah Al-Ahmed: Well, thankfully you've created all these resources online that can allow people to go in and learn more about these things. Which brings of brings me to my last question. You spent all this time learning about the aurora, dedicating yourself to the science of the thing, but why is it so important to you to not just do that step, but also share it with everyone around the world online?

Vincent Ledvina: Well, I mean, it goes back to being four years old and seeing the aurora. It was such a unique experience and so powerful for me. I mean, now my entire life is aurora chasing so it's had this profound effect on me, and I've heard these stories from many other people. I got this really nice email the other day of this woman who came up to Fairbanks and saw the aurora, and her entire life has been changed just from that experience. She's planning on being an aurora guide in Fairbanks now, and she lives in Seattle working a 9:00 to 5:00 job at, I think, it's a marketing firm or something. She's completely shifting. I had a similar experience when I was up here in 2022 in Fort Yukon, Alaska, helping out with that sounding rocket. I mean, I looked up at the aurora and I just broke down. I was crying. I mean, it was just amazing. You see this thing and your entire life almost just changes. Your perspective on everything just gets shifted. It's an experience that's unlike anything else. If you haven't seen the aurora then you just haven't seen the aurora. You just can't replicate it. I mean, maybe you can go to a planetarium and see a good show, and have that 3D and surround vision experience, but you really have to get up here and look at it for yourself. And I think the power of that connection that you can get with nature through the aurora is just something that I want everyone to experience. I want everyone to have at least a chance. Nobody has to see the aurora, but a lot of people want to see it and don't know how, and my goal is just to give everyone the chance to do it and to have the same experience that I have.

Sarah Al-Ahmed: I think so much of science is about this. There's a lot that we can do practically with it that enhances our lives. But at a very basic level, it's about the interconnectivity between us and our planet and all the universe around us. And I can think a few examples that are as profound as the connection between our star and our world and the world's beyond. It's a beautiful moment, and I hope that I and all of our listeners out there get a chance to experience that. But in the meantime I'm going to leave links to all of your social media and your blog and everything on the web page for this episode of Planetary Radio, so if anybody just needs to take a moment and watch the aurora they can do that. So thank you for joining us.

Vincent Ledvina: Yeah, thank you.

Sarah Al-Ahmed: Happy aurora chasing, everyone. It's definitely on my space-life goals list. And if it's something you'd like to experience I wish you all of the luck. Now it's time for What's Up? with our chief scientist, Dr. Bruce Betts. Hey, Bruce.

Bruce Betts: Hey there. Hi there. Ho there.

Sarah Al-Ahmed: I wish I had your energy, because I'm going to be at NIAC all week and I'm going to need it, so give me some of that.

Bruce Betts: I'm just faking it, as will you when you perform.

Sarah Al-Ahmed: Ain't we all?

Bruce Betts: And for some reason you should talk with this voice.

Sarah Al-Ahmed: I'll work on it, my announcer's voice. So I just recently, I literally just today, got out of my conversation with Vince Ledvina, The Aurora Guy, about-

Bruce Betts: Aurora Guy.

Sarah Al-Ahmed: The aurora on Earth and the aurora and on other worlds, and the connection between all these things. It's all connected, man. But during the conversation he brought up the fact that Mars doesn't have this global magnetic field the way that we have here on Earth, and that impacts whether or not we could see aurora on that world. Which we do. We've observed them with some of the rovers on the surface, but it's clearly different. So why is it that Mars's magnetic field is so different from Earth? What caused that?

Bruce Betts: Dude, I have no idea. No, I'm sorry. Sorry, you got me in a strange place. Mars, being smaller than the Earth, as time passed we presume that the interior largely stopped being as liquid. It cooled off relative to the heat being produced from the inside, or leftover from original formation. And you need that swirly, conductive stuff inside your planet to generate a global magnetic field. And so that is the general theory of why there's not a global magnetic field now. However, weirdly, there are localized fields because there was a global magnetic field on Mars, then it actually is the happy little lava came out with the iron and magnetic things that dig magnetic fields. All the little iron friends lined up and froze into rocks with a residual magnetic field. And we see this on earth as well, in fact. It's one of the ways you see the complete flipping of the Earth's magnetic field is in the mid-ocean ridges and the lava that's flowed out over hundreds, thousands and millions of years, and you see the field locked in different ways. On Mars you've got these areas where it's actually locked in, and with our sensitive magnetometers that they sent more and more sensitive ones, you fly over, especially on the close part of the elliptic orbit that they were in, and they detected these frozen-in magnetic fields of a smaller magnitude. But they're still there, but localized and without the global magnetic field.

Sarah Al-Ahmed: Earth is bigger than Mars. But we've also been through some serious calamities in our past. For example, we had Theia, that almost Mars-sized planetesimal smash straight into the earth and then form the Moon. And I wonder how much of the residual heat inside of our planet, or the fact that it went through that upheaval has anything to do with it.

Bruce Betts: It would've changed and affected things, but fundamentally you have a couple of sources of heat generally inside a planet or a moon. You've got the radioactive stuff that's still kicking off heat, the uranium, potassium and thorium, and then you've got the residual heat from when the gravitational collapse occurred that formed it originally, which oddly enough dumps a bunch of heat when potential energy transfers into thermal energy. And so you got all this heat that wants to get out. And then there are indeed these weird things, that being the biggest calamity we know about, slamming into earth and kicking off what eventually was the Moon. And a lot of stuff fell back. But if you don't mind a small mathematical little side note that generally drives these things. I just in passing said, Mars is smaller, therefore it cools off faster. It is fundamentally the fact that volume is proportional to the radius cubed, and surface area is proportional to the radius squared. Volume is what generates your heat, such as from the uranium, potassium and thorium, and surface area is where the heat can escape to the surface. So the bigger you get, the more the R cubed dominates over the R squared, and so you retain the heat more preferentially as opposed to a small body. There you go. That was fun for me. Thank you.

Sarah Al-Ahmed: You're welcome.

Bruce Betts: But if you really want magnetic fields you go out to the giant planets.

Sarah Al-Ahmed: Right. And the aurora we've seen out there are absolutely bonkers, right? Those images from Juno of Jupiter with that one created by Io. The first time I saw that video of that little aurora being dragged around, you can literally see it's point where it connects to Io on the planet in the data, it's so cool.

Bruce Betts: No, it's very cool. And Jupiter of course, irregardless of the moons when their cool stuff has a very strong aurora that can be seen, particularly at certain wavelengths it makes it easier. You've got nice polar circular aurora-looking nodules, and then you get the interactions between that and all of the inner moons. Amazingly, you have a global magnetic field from Ganymede, that's like its own little friend, presumably from probably salty, more conductive water flowing around rather than a lot of iron or iron nickel, but it's got its own. And then a lot of them have induced magnetic fields from the interaction between the strong Jupiter magnetic field and those, et cetera. And all of this is why you whip around all sorts of charged particles and make a dangerous radiation environment for missions like Europa Clipper who goes, and you have to really try to protect your spacecraft when you get in closer because of that whipping around magnetic field. Because also, that Jupiter is the fastest rotating planet in the solar system, so it's just crazy out there.

Sarah Al-Ahmed: Bonkers. But really good to get the news about Europa Clipper on Tuesday, about the fact that it's actually going forward, the mission's all ago. I'm so excited. This is going to be great.

Bruce Betts: It is. It's going to be great. I mean, they don't get there until 2030, so chill a little bit, but very exciting, very cool mission, and should be exciting. And then you got the Europeans with Jews going out to focus on Ganymede, but do a little Europa work. It'll be a fun time in the Jovian system.

Sarah Al-Ahmed: All right, so what's our random space fact this week?

Bruce Betts: Random space fact, random space fact, random. So our solar system, we're going big, bigger than usual. Our solar system orbits the center of the Milky Way at, as you know, about 828,000 kilometers per hour, or 230 kilometers per second. If, and this is probably a very odd thing to think of, but if you applied that speed measured relative to the whole galaxy within our solar system and you had your little spacecraft traveling at that speed, you could go from the earth to the moon in about half an hour.

Sarah Al-Ahmed: Dude, that's awesome.

Bruce Betts: Hey, cool.

Sarah Al-Ahmed: Kind of terrifying, honestly. We're all just whipping around that galactic center.

Bruce Betts: Yeah, we're whipping. Yeah, we are. And yet it's so big. How big is it? It still takes a quarter billion years, on average, to go around. So our galactic age is 10 or 12 or something.

Sarah Al-Ahmed: Wow.

Bruce Betts: All right, everybody, go out there, look at the night sky and think about what type of magnetic fields you've played with during your life. And did you enjoy it? I know I have. Thank you, and good night.

Sarah Al-Ahmed: We've reached the end of this week's episode of Planetary Radio, but we'll be back next week with my adventures at the 2024 NASA Innovative Advanced Concept Symposium, or NIAC. I know a few of our listeners are going to be there and I'm looking forward to high-fiving you all in person. If anyone else wants to watch, I'm going to be hosting the webcast, which you can find on the NIAC website. If you love Planetary Radio you can get Planetary Radio t-shirts at planetary.org/shop, along with lots of other cool spacey merchandise. Help others discover the passion, beauty and joy of space science and exploration by leaving a review or a rating on platforms like Apple Podcasts and Spotify. Your feedback not only brightens our day, but helps other curious minds find their place in space through Planetary Radio. You can also send us your space thoughts, questions and poetry at our email at [email protected]. Or if you're a Planetary Society member, leave a comment in the Planetary Radio space in our member community app. I'd love to hear about your aurora chasing experiences, or where you hope to go in the future. Planetary Radio is produced by The Planetary Society in Pasadena, California, and is made possible by our members who relish our scientific journey to understand our place in space. You can join us and help support space science and exploration at planetary.org/join. Mark Hilverda and Rae Paoletta are our associate producers. Andrew Lucas is our audio editor, Josh Doyle composed our theme, which is arranged and performed by Pieter Schlosser. And until next week, ad astra.