 It's Monday. It's one o'clock rock. We have Heather Caluna here. She is a postdoc fellow at HIGP, the Y Institute of Geophysics and Planetology, and she is into space weather. And that is exactly why we're calling this show Space Has Weather to Eye Heather. Hey, how's it going? It's good. Now that you're here. So, buzz is thus with weather in space. I mean, are you kidding? No, I'm not kidding. I mean, weather on earth, for the most part, is stuff that erodes surfaces, right? So, if you leave something outside, even if it's just a pair of slippers, over time it starts to get dried, eroded, a little bit like gray, right? The colors change. And so, the same thing happens in space, but there's different processes that are responsible for it. So, for example, I'm interested primarily in micrometerite impacts. Would you say that again? Micrometerite impact. I haven't heard of that. We do not discuss that at my dinner table. Oh, wonderful. Kiskesekusah. It's basically little dust particles flying through space that impact different surfaces. And space weathering really is important only for those bodies that don't have an atmosphere. Basically, they don't have something to protect them from these particles. And so, when you look at the night sky and you see a little shooting star, that's basically speck of dust entering our atmosphere. And so, if I was on an asteroid, for example, I didn't have an atmosphere. That speck of dust would come straight through and hit me. And so, it would hurt you. It would hurt me, just a little bit. Of course, these objects get bigger in size and we see, you know... It would hurt more. It would hurt a lot more. But fortunately, those occur much less frequently. So, yeah. So, space weathering, primarily, what I study is these micrometerite impacts. But there are other sources of space weathering, such as the solar wind. And so, are you familiar with the solar wind at all? So, it might be a bit of a surprise. It's kind of like the wind we have here on Earth. You know, it's a flow of particles that are moving past you. The solar wind is a flow of particles that come out from the sun. And so, these happen to be charged particles, like hydrogen and helium. And so, these particles, as they fly through space, can also impact surfaces that don't have atmospheres. And they also erode the surfaces over time. Like sandpaper. Kind of like sandpaper. Dig a little hole. Very fine sandpaper. Very fine sandpaper. Like sandblasting. Like sandblasting. Slower though. Yeah, exactly. Oh, how interesting. So, you call it weather. That's pretty loose connection, isn't it? I mean, what does weather mean in the space context? It means solar wind. It means micrometer. Micrometer, right? Impact? Impact. What else? Well, those are the two major components for the most part. I mean, but you also have, you know, solar radiation. So, you have sunlight hitting your surface. Really? Yeah. You have stuff baking, basically, in the sun. Yeah. So, these things, these things are, it's not constant. Not the solar wind, not the micrometer impact, not the solar radiation. They change. Well, the solar wind and the solar radiation is pretty constant, right? So, we're constantly receiving sunlight from the sun. It only gets dark on earth because our portion of the earth rotates out of view of the sun. But the sun is still shining. And so, the solar wind is operating the same way like the radiation. It's constantly flowing out of the sun. You might have some bursts due to some activity on the sun. You might have an eruption on the surface of the sun that sends out basically a large surplus of these particles. And so, in that sense, you can get a flux or a variation in these particles. The micrometer rates now, you're right, that does change. You know, that isn't constant. What changes the rate of micro impact? The impacts depend on where your object is. So, if you look at the moon, for example, you have impacts, you know, occurring every, I don't know, every 10 seconds, every few minutes. Okay. But as you get to different parts of the solar system, so you get further out towards Jupiter, you're going to have a different density of dust. There's not going to be necessarily as many particles. And so, you won't have as many, your frequency of these impacts is going to be less. So, your job, I'm sure you decide to accept, as a space weather person, research person, scientist person, is to find out what causes these changes. Am I right? Or where you can find these phenomenon? And what makes them happen here, not there, or happen this way, not that way? Tell me what it is. Yeah, basically. As my astronomy background takes me into observing asteroid surfaces. And so, what I want to see is actually how these processes affect the surfaces over time. And so, I look at young asteroids and I look at old asteroids and I see how do they change? How does the spectra of these asteroids change? So, you're looking at the surface to see how they were beat up by these various phenomena. And how it manifests in the colors or the spectra of the asteroid. And so, are you familiar with a spectrum? No. I assume I'm a carte blanche. Okay. A rainbow is essentially a spectrum. So, when you take white light and you shine it through a prism, and it produces a rainbow, that rainbow is your spectrum. Except instead of recording on a telescope computer, it's recording on your eye, right? You see those colors and they're recording on your eye. But what you're taking, what you're doing is you're taking that white light and you're splitting it into a bunch of different colors. So, you're splitting it into its individual components. And so, what I do is I study these colors of these asteroids. And over time what we see is that certain colors actually get affected more prominently than others as a result of space weathering. And what happens is, unfortunately, this is where space weathering, there's a downside to it in the sense of we use spectra. So, we use these colors to try to understand the compositions of asteroids, right? We can't send spacecraft there any time we want. It's an expensive endeavor. Very rarely have we been able to sample these asteroids. They move fast and they have orbits that you don't know where they're going, I guess. It gets pretty complicated. And then it's even more so complicated to, say, land a spacecraft on an asteroid, collect a sample and bring it back. Oh, that would be hard, wouldn't it? That would be hard. And we would regret probably having tried. There is one, the Japanese actually have done this for an asteroid that was nearby Earth. The human person? Not a human person. It was a robotic. Nice machine. Yeah, yeah. No, people are necessary. But it successfully landed on the surface. Some dust on the surface got knocked into a little carrier that got delivered back to Earth. And so that's the only asteroid we've ever directly sampled. So, if you got the dust from the whatever the container was that the Japanese picked up off the asteroid, what would you do with the dust? What would you look for? How would you look at it? Right. So, there's people who actually specialize in this. And this is a little outside of my field. But what I do is, aside from my observations of asteroids in the lab, I simulate these processes by using a laser, a pulse laser that basically heats up and vaporizes whatever sample I put in, you know, my lab. Could be a rock. It is a rock. Usually a ground up rock. Okay. So, to simulate the dust that you see on the surfaces of the asteroids. But what I'm trying to simulate is exactly what we find in these samples that the Japanese picked up. So, we see these little melt blobs, right? They're basically regions where the little micrometer it came in and hit the surface. The heat from that impact vaporized some material and some of that material cools down and recondenses on the grains surrounding it. How can you tell the difference between the material that was vaporized and fell back down again and the material that was there in the first place? So, you can actually, I mean, just looking at, there's really amazing instrumentation nowadays that can get you really down to a very fine scale. Basically, you can see, you know, things on the scale of the thickness of your hair. And so, you get down to this detail and you actually start to see things pop out. And I mean, it literally looks like a giant melt blob. Like you like piled a big glob of glue on a melt grain. And it's like, okay, that's not a normal mineral structure. So, you compare it against what you see in the background. Exactly. And it looks different like a blob maybe. Yeah. And then you start looking at that. So, now you have your blob. Right. What do you do with the blob? So, I actually take a step back. Okay. We know about space, actually from the Apollo missions. So, the astronauts brought back samples from the moon. Okay. And these samples included rocks and soils, right? So, some of this space are this lunar dust. And when you look at the lunar dust, you can actually see these same things, these melt blobs. We can also see, if you like cut one of these lunar soil grains in half, you actually see that there's a glassy rim around some of these grains. And within that glassy rim, there's nanometer sized metallic iron particles. And so, this is not always, but for the most part, you know, we see it pretty pervasively in the sample. Okay. And so, it's interesting because people wondered, oh right, you know, what is this that we're seeing? What's causing it? And part of what I'm investigating is whether or not, you know, is the solar wind that isn't primarily responsible for producing these features or is these micrometer impacts? And so, there's a big question about which one is the more dominant process. However, what's interesting is that if you look at these soils, right, that were collected directly from the moon, and if you compare it to a soil that you make by grinding up a lunar rock. Sorry, I don't know the answer. Oh, that's so interesting. That's an echo machine. She must have said something that triggered her, but clearly she didn't know the answer. She doesn't know the answer. That's really interesting. I did that to my phone recently too, I don't know. Maybe it's my voice. This is time for a break. We're going to take a short break and we're going to turn her off. Okay. Okay, that's Heather Kaluna. She's a postdoc fellow at HIGP at UH Manoa, and she's studying researching space weathering at HIGP. This is research at Manoa. Space has weathering too. We'll be right back. Hi, I'm Ethan Allen, host of Lakeable Science on Think Tech Hawaii. I hope you'll join me each Friday afternoon as we explore the amazing world of science. We bring on interesting guests, scientists from all walks of life, from all walks of science to talk about the work they do, why they do it, and moreover why it's interesting to you. What the science really means to your life, its impacts on you, how it's shaping the world around you, and why you should care about it. I do hope you'll join me every Friday at 2 p.m. for Lakeable Science. Looking to energize your Friday afternoon? Tune in to stand the energy man at 12 noon. Aloha Friday here on Think Tech Hawaii. Aloha, my name is Mark Shklav. I am the host of Law Across the Sea. Please join me every other Monday to hear lawyers from Hawaii discussing ways to reach across the sea and help people and bring people together. Aloha. Okay, we're back on Research at Manoa, one o'clock clock on every Monday. And we have Heather Kaluna. She's a postdoc fellow at HIGP, the Hawaii Institute of Geophysics and Planetology, and you're talking to us about her research, which is space weathering. So Heather, how did you get into this business? This is, I mean, did you wake up one morning and say, I like to study space weathering. Well, really it's an interesting question. I got into this business through my PhD program. Which was? Astronomy. So I went to the Institute for Astronomy, which is our master's and PhD program at the University of Hawaii at Manoa. And when I first went there, my advisor, she's actually someone who we call an astrobiologist. Have you heard of an astrobiologist? I have, but I never did understand it, though. It's basically an interdisciplinary sort of perspective on astronomy and life in the universe. And what she did when she, you know, I was trying to find an advisor, she spoke to me about this topic that I just, it just hit me and it was so amazing. And the topic is the origin of earth's water. And you might be thinking, how is this related to space weather? I am thinking that. And I will get there. But what's really interesting is that we think that earth forms so close to the sun that it actually was too warm for it to have its own water. And that water had to be delivered through impacts from comets and surprisingly wet asteroids. And so I got really interested in these wet asteroids. Because it was a mystery. It's a mystery. And I'm born and raised in Big Island. I'm a water girl all the way through up by the beach. And so really being able to study water in space was really fascinating to me. However, in order to characterize which asteroids have water on them, getting back to these spectral features or these colors and these fingerprints. If space weathering is removing and making some of these fingerprints disappear, that reduces our ability to detect these water-rich asteroids. Or characterize their water compositions. It's like the traces of what happened before washed away like in the beach. The sand and the waves wash away the history of it. You slowly start to see the words disappear every time the wave comes up, right? And so that's why I got into space weathering. It's like, I'm really interested in this question of how much water did asteroids contribute to earth's, you know, our oceans? And so in order to answer that, we first have to look at this question of space weathering. How does space weathering modify these features that we used to characterize the water and the water histories? Can I roll it back for a minute though? Why do you say water? Water is so easy to make, more than it is hydrogen and oxygen. Why wasn't there hydrogen and oxygen here on earth? And why wasn't there some sort of natural process, some kind of physical phenomenon that happened that put them together as water? Why does it have to be external delivery? Right. And so that has to do with the temperature basically, right? So when you look at the interplanets, they're primarily rocky bodies, right? But as soon as you get out to, you know, the interplanets are like Mars, Mercury, Earth, Venus. But as soon as you get out to Jupiter, the game changes, right? You have suddenly a huge massive planet that has actually a ton of hydrogen in it. And this has to do with the fact that there was a certain temperature in our solar system when it was forming. So when our planets were forming, there was a certain temperature away from where the star is warming, our sun is warming, basically in the center, where the temperatures get cool enough that water in that vapor, basically in the gas, that's what we call it, the solar nebula, that water exists as a gas form close into the sun. And once you get to a certain distance, that vapor can actually turn into a solid and can turn into water ice. And so as little... Vapor is steam, we're talking about steam, right? Basically, yeah. And so this vapor, once it becomes solid, can now become incorporated into these, we call them protoplanets. They're like little planetary embryos of a sort or eggs. And so that's where it becomes important, is because if you're too close to the star, if you're too close to the sun, you're only going to have solid materials that are hitting each other and sticking to each other, right? You're not going to have gases that just suddenly collide and clump together. Like, we don't see that, you know? Well, why? Why not? Because the sun will burn them off or the gravity of the sun will pull them in. Why are they not there? So the water is there in vapor form nearer. But you can kind of think of it as like, you know, if you're outside and you're throwing around a bunch of pieces of mud, are you going to have the water and the air stick to the mud? Not necessarily, right? It's the mud that's going to be sticking to each other for the most part. Yes, I see. And so that's essentially what's going on. I mean, that's the best analogy I can come up. It's a medium. It's a medium, right? And so basically the inner planets only formed from the stuff that was solid. And most of the planets in the outer solar system like Jupiter, Saturn, whatnot, because they were about to form from a combination of ice and rocks, right? They got their cores built up very quickly. Their gravity became so massive that they actually could steal some of the gas, the hydrogen gas that was around them. So that's why they have these giant gases envelopes. But Earth and the other planets in the inner solar system never got big enough to be able to trap gases quite like that. So have you been developing a theory about how all the water actually got here, the delivery of the water? I mean, I can imagine these planets that are largely water somehow, and what they come down from heaven and splat. They're on Earth. I mean, I've splashed the wrong stuff. No, splat's great. I like splat. Because that means it's a nice wet asteroid. Is that... I mean, do you have a theory about how this happened? So this is actually a little beyond what I do. And that's where we have these big picture questions in science. So this is the end game. This is the gold medal once one day, hopefully, once we piece together all the little components that everyone's working on, we can actually answer that question. So I'm personally not trying to figure out how these asteroids got here. There's people who design models and try to see if Jupiter and Saturn moved in our solar system as it was forming. How does that toss things around? And they look at that kind of thing. But instead I'm looking at these spectral features of these asteroids to see, given this knowledge of what we see today, can we trace back to what these objects were like when they first formed, so that way we can actually see these impacts that hit the Earth early when it was forming. How much water did they give us? Okay, so you know what's happening today because you can... Well, I'm trying to figure out what's happening today. Well, aside from the Japanese dust, how else can you do spectral analysis of what's going on on the asteroid? I mean, you can look at it through a telescope. So I go up to Monocale. I've spent quite a few nights up there sitting at the telescope and I tell you, it makes you quite loopy up there, I swear. Oh, sure, when you get to it, I've been at Manaloa and I know how that works. Yeah, it's a very subtle difference in elevation there. So yeah, so I use the telescopes. We have special instruments that take the light coming in from an asteroid and make a spectrum out of it. So we have basically a prism inside the telescope that splits the light up and we can start to search for those fingerprints that tell us that there's water-rich minerals on these asteroids or there's water itself on the asteroid. Okay, so now you know the composition which is complicated of an asteroid. You know about the globs and everything on the asteroid and so you're learning the real-time characteristics of the asteroid and the existence of the water on the asteroid. But how can you compare that against the way it was a long time ago? You can't see that anymore. How do you know the way it was a long time ago? So this is where models come into play and so that's why the observations are very important because in order to really... I mean you can model anything honestly and say this is how it was but if you don't have the observations to really give it some ground truth you're not going to be able to say much. And so that's why these observations are important because if I can say these many asteroids have water on them then they can start to say okay well based on our model of the early solar system and the temperatures and the amount of bodies that were in that region they can say this is how many objects we expected to impact the Earth based on our model and so it really comes down to taking the observations and tying it into the models. So you're working it backwards? Working it backwards. That's all we can do is work it backwards. Yeah because you know I mean we're talking about what millions of years ago? Millions, billions of years. Millions, oh sorry. Yeah, I mean yeah. Okay so this is pretty sophisticated stuff. What kind of interest... I mean if I go with you one morning to your laboratory in HIGP and I walk in what am I going to see there? Can you describe it for me? Yeah so you basically have this long rectangular tube that actually houses a laser and so it's an infrared laser and we can't actually see that with our eyes. Okay. And so if I was to turn it on you wouldn't actually be able to see it like fire out a bit too. It wouldn't hurt me though. It would hurt you. Oh sorry. It could zap you. So like if we put a little piece of paper in front of our laser it goes zap. And so you know I won't... I don't think you'd burn a hole through your hand unless you just leave it there. And so yes so you have this laser it goes through there's a couple lenses to help redirect the laser down onto our sample. Our sample itself actually sits in this chamber it's this giant metal around it's almost like a ball. Okay but it's only this big? Yeah it's not very big. I mean our sample is we literally I use a half a gram of powder in our samples. But we put it inside this chamber and we shut the chamber and we actually pump the air out of it. So we try to get it down to pressures that are close to what we see in space. So very very low very low vacuum type pressures. Just trying to emulate the pressure in space you're not getting getting it down to zero. Exactly. Zero okay okay. Yeah and so yep so we put our sample inside the chamber close it get the air out of there and we turn on the laser and it's pulsed so it's meant to sort of speed up the impact process right so the impacts don't occur you know instantaneously and continuously like you're asking but we'd also don't have time to stay here and simulate it exactly according to the rate that happens in space. Yeah. So we speed up the process by pulsing the laser right and so we do you know once every 20 second or sorry 20 pulses a second is how quickly we're actually bombarding our sample. Okay. And so we do that for whatever period of time we're interested in doing it for. Until lunch. Until lunch. Usually I'll do like a few minutes take it out of the chamber and then I have a spectrometer and so this is a thing that images you know it takes the light splits it up and it images my sample so I can actually see how these features vary. So you can see that the elements from the periodic table what's what right. Isn't that what this spectroscopy does. Yeah but instead of elements we're actually looking at minerals so there's specific features that correspond to minerals like all living and purexing. My favorite minerals are the ones that I'm interested in are these clay minerals so they're basically muddy clay minerals. Because there's water in there. Yeah because there's water in there. And we call them phylicits and really honestly as a graduate student coming from an astronomy background this is a whole new ball game. Sure yeah and there's some pictures we had a picture a minute ago. Okay so all right so I just want to get you know we have a couple minutes left I just want to get where this fits you spoke before there are some scientific leaders out there who've been thinking about the comprehensive and where where all this fits of what you're doing and others and you know sort of the look back on how it was way back when and how and sort of to find lessons about how the universe works and how the the weather works and those three kinds of weather phenomenon that you have. I mean they become important for asteroids I mean you know when you talk about space travel yeah these processes are important understanding how do they affect people much less you know asteroids is an important thing to quantify. I mean if you're on an asteroid or if you're on a planet if you're on Mars. If you're on the moon you know these kind of things it could be bad you could have the solar storm it would really give you a headache. Exactly. So what about identifying asteroids coming in that's not part of it though. That's not what I do but there are people who do that. Yeah. And so but that's yeah that's right. So I'm Joe Blow walking down the street. Okay. How does your research affect me and that's a hard one I know how does your research affect me what what how are you thinking of me and how should I be thinking of you in terms of the connection of science and our daily lives. I think there's two answers I could give to that. The first one comes back to this origin of water you know that's really water is essential for life and so it's kind of getting back to our origin story from a scientific perspective and I think that you know is important to anyone you know I think religion is a big thing because people care about their origins and so I think that's why what I do is really important at least to me and the other answer is you know aside from our origins it's also our future and so if we look at space travel and space flight you know there's a whole new group of people trying to you know SpaceX all these groups that are trying to develop technologies to have more space travel and what one of the possibilities that we can do is actually well this is a idea that is floating around out there and I think it's exciting floating is the opportunity to look again but the idea is to use asteroids with water on them that have these clay minerals to refuel so say you know you're flying through space and you only had so much fuel to get you to say the moon but there's an asteroid nearby that has water features on it and you can say hey look at this asteroid I know there's water on it I can stop by there have my little contraption whatever that's for someone else to get the water out of it get the water out of it refuel my spacecraft and then mosey on to wherever I want to go next but it raises I mean that raises maybe it's inherent in that question but it raises in my mind another question that is you know we're having problems with water already on this planet and in the years to come we'll probably have more profound problems with it and maybe just maybe we'll find out more about water and the origin of water we'll find out how it got here in the first place maybe we'll find out how to get more of it is that part of what you're doing I've never thought about it like that but that is an interesting perspective hopefully we never have to get to that point but one of the things that does one of the questions that does pop up in this research topic is you know is the water on the surface of the earth all the water that is right so we have oceans and there's you know a sea floor but what about the water is there water trapped in our mantle is there water trapped in the magma the lava that is beneath our surface of our earth and people think there is and some people think there might be like five times our oceans worth of water submerged in the magma and we can learn about that from looking at space can learn about water which is an essential part of life yeah it all fits into that story it's another piece of the puzzle yeah another piece of the puzzle well thank you for working on the puzzle for us thank you for appreciating come back and talk more about your studies and your research and your writing this is heather kaluta she's a phd in astronomy at the ifa then she's a postdoc fellow at higp studying space weathering what an interesting discussion thank you for that I hope you enjoyed thank you very much awesome I love you