9UNP1712HD_Dhanesh_Krishnarao_WordPress

- Good evening, and welcome to UW Space Place. This is one of our Tuesday evening public talks, and tonight I'm very pleased to introduce Dhanesh Krishnarao, who is an advanced grad student in the UW Astronomy Department, and he'll tell you a little bit about his own research. But tonight he's going to tell us about space weather.

Dhanesh comes to us from American University in DC. He's originally from Philadelphia, so he's going to get a PhD here in astronomy from Wisconsin and work on things much bigger than space weather. But he'll mention that in a few minutes. But the really intimate astronomy of space weather is what we're going to hear about tonight, so please welcome Dhanesh.- Thanks, Jim. Hey, everyone. I'm Dhanesh, like Jim says. I usually just go by DK, so you can just refer to me as DK. What I'm going to be talking today about is space weather, which relates to our sun and Earth and is something that can affect our everyday lives, but before I really get into that let me just introduce myself a little bit. Who am I? I'm DK from UW-Madison, a grad student here. If you're on Twitter you can follow me @DK_and_a_bit. I also have this conveniently named domain name, www.astronomy.dk. It's a Danish website that I bought. It currently just redirects to my Wisconsin page, but eventually will be kind of a fun website about me. So what I do in Madison is not space weather. I study our galaxy. I'm a grad student here, I study the interstellar medium and gas in our galaxy. So really, who am I to tell you guys about space weather, and why am I going to talk about space weather? It turns out in a past life, as an undergrad when I was in the DC area, I worked as a space weather forecaster at NASA through an internship program for almost three years. So I was at Goddard Space Flight Center, trained to do space weather forecasting, and I'm going to start off by showing you guys this admittedly very cheesy video that was made of me and of what I did as an undergrad following space weather. This was done of me as an intern. I'll go ahead and start that now and just kind of let that play through. 
(upbeat music)

When I was four we went on vacation to like Disney World, but the main part of that that caught my attention was we went to the Kennedy Space Center and when I was there I instantly fell in love with space and astronomy and wanted to be an astronaut. My name is Dhanesh Krishnarao. I usually go by DK here. I'm a rising senior at American University, studying physics and math. This summer my research project I'm working on is to develop a system where spacecraft operators can look up specific space weather conditions near their spacecraft. Space weather is getting really important now, especially since there's more and more dependencies on satellites and technology. Different space weather events can cause radio blackouts, knock out GPS systems. So I think what I'm doing is going to really help out with making sure that the least damage is done. The most exciting thing I've done this summer is probably one of the days when all of the other forecasters were busy. At this time no one else was free 'cause they were all attending conferences, but they decided to put me in charge for the day. I think Goddard's a great place to be. Everyone's very enthusiastic. Since last summer, as soon as I got here, I loved everything here. One of the main thing I liked here a lot was being able to play ultimate Frisbee every Tuesday and Thursday with all the NASA employees. Overall, I just love being at Goddard. Everyone here is very nice and it's been a great experience.

So like I said, a little cheesy, It's a little bit weird, but it talks about a lot of things that I'm going to be covering today, so what space weather is, why it's important, how it can affect our everyday lives and why I'm going to be talking about it is because it took up a large portion of my life before I got here, and I really grew attached to it and think it's very interesting. Okay, so to get started, to understand space weather we really have to start with Earth, our home. We live on Earth, it's our planet. I hope we all love it, I do. So what space weather is is just broadly defined as any kind of process or processes that happen in space that can affect Earth or the near-Earth environment. That includes in orbit around Earth. It even can include different planets in our solar system or our moon, and it can also affect our everyday lives on the ground and cause different effects that we can see on the ground, feel on the ground, and affect our electronics on the ground. So it can have huge effects to our everyday lives. What actually causes these effects? For this, we go back to our sun. I like to just start off kind of, I'm sure you're all aware that our sun is huge, but it's really hard to appreciate, really, how big the sun is. I still don't know if I can understand actually how big it is. This image here, you might see a label for the Earth. If your eyesight is very good, mine is not, you might see a little dot that is showing the Earth to scale there in the corner. You should notice that you can almost hardly see that dot because the Earth is so small compared to the sun. If you're a numbers kind of person, you can fit about 1.3 million Earths inside of our sun, but that can only help me so much understand how big the sun is. I hardly can even tell you what $1 million looks like, so who am I to judge what a million Earths is? The sun is huge. Here's a little bit closer up view, so you might actually be able to see Earth here in the bottom corner. And you can see the sun is much bigger, doesn't even fit on the screen. And what you're seeing here is an eruption off of the surface of the sun, and these massive eruptions of the material on the surface of the sun and through the atmosphere of the sun are what gets released throughout the solar system and can sometimes come zooming towards Earth and impact us and cause these space weather events. You can see that even one small explosion, small, is actually quite huge and enormous, especially when you compare it to the Earth. So these are the kinds of phenomena that cause space weather.

If I was to break down what space weather is and everything you need to know about space weather in one slide, it would be this.

Everything starts on the left and progresses over to the right. We start with our sun, where we have all of the energy that we get, but also every now and then the sun can unleash an extra burst of energy through explosions. These explosions of the atmosphere can slowly propagate through space, through our solar system, and impact different planets and satellites that are spread throughout. Every now and then the Earth might be in the way and could get impacted by one of these events. But luckily, at least in this image, Earth is protected by this magical purple blue shield. So it's not really magic, it's the Earth's magnetic field that is working as a way to shield us from a lot of the harmful effects, but it's not perfect. There's still some harm that can happen, but also some beautiful sights that can happen from it as well. So if you have ever seen the northern lights, aurora borealis, that is an effect of space weather. So that is something that happens when these large solar events impact Earth. So what I'm going to do over the course of this talk is kind of just break apart this image one piece at a time, show you each step, what's happening at each step, and then end by talking about what we can do and how we actually can forecast and try and predict these events and protect ourselves.

So starting with the sun, like I said, everything starts when the sun unleashes massive amounts of energy and starts the solar storm. The first warning sign and event that we see is what we call a solar flare. So in this animation, within that red circle, you might notice that it gets really bright. This is a solar flare happening, which is really just an intense brightening on the surface. When this happens it releases a lot of energy, a lot of X-rays, really high-energy light that can be harmful to us. And that, of course, travels at the speed of light, reaches us in eight minutes, and is our first indication of something potentially bigger to come. You might notice in this animation, it's a little bit hard to see, but you might notice if you look carefully around where that brightening happens, that you see some what looks like puffy material exploding off of the surface as well. So that is the next kind of step. Here's just another solar flare. By the way, all of these images are from different satellites, which I'll be talking about a little later as well. And the different colors are looking at different wavelengths of light, and each different color is telling us a different temperature of the sun, a different temperature of the gas and material that we're looking at. So here the brightening is happening around here where it zooms in, and you might also notice nearby shortly after it gets very bright, you can see some kind of loops erupting off of the surface and leaving the influence of the sun.

What is happening there when you see those kinds of eruptions is what we call a coronal mass ejection. The atmosphere of our sun is called the corona, so it's just a coronal mass ejection, meaning part of the corona is being ejected out into the solar system. Here is one case of that happening. You can see this loop of material exploding off of the surface of the sun, and this usually happens because the sun has very powerful magnetic fields that sometimes get really tangled up and wound up. From time to time they can get so tangled up that they break and release their energy outwards, and with that, some of the material off the surface and within the atmosphere of the sun will also follow along and be ejected out.

This animation is actually from that same still image I showed earlier, where Earth was a tiny dot in a corner. So it kind of just shows you the scale of these eruptions that can be happening. The kind of energy associated with a single explosion like this is millions and millions of times more powerful than any of the most powerful nuclear bombs we've ever created on Earth. These are happening roughly two to three times per day on the sun during solar maximum, and maybe just like once every day or so during minimum times of solar activity. So they're happening all the time, they're just also happening everywhere throughout the sun, so they're pointed in many different directions and every now and then can be pointed towards Earth, and that's when we have to be careful.

We can also look at these coronal mass ejections a little bit more carefully if we zoom out. What this image is doing, here's another coronal mass ejection happening, going off to the right-hand side.

The way this camera is working, it's from a satellite image, so it's looking at the sun. The sun is located at the center behind of that white circle, and you can see around it it's pretty dark and that's because literally the way to look at the much fainter atmosphere of the sun without actually seeing the rest of the sun is to just block it out with a disc held in front of the camera. It's literally just a disc being held in front of the camera, blocking out the really bright part of the sun, essentially creating our own eclipse so that we can see the faint corona around the sun and try and actually see these coronal mass ejections, or CMEs, and measure them over time. That's what can allow us to predict how quickly they're traveling and see when they might impact Earth.

Once they reach Earth, it typically takes about two to three days for one of these eruptions to reach Earth if it was pointed towards us. It will impact Earth, but like I said, we have this so-called magical blue shield. It's our magnetic field. Earth, luckily, is essentially just a giant magnet, so the magnet is able to repel these energetic charged particles that are coming off of the sun from this coronal mass ejection, and repel them across us. It ends up creating this deformed magnetic field shape where you'll see in a minute it looks more like a bullet, and that's what really protects us from the harmful effects of the sun, but it isn't perfect. Some of that energy can still leak through. You'll notice that when the storm passes by it's kind of compressing the magnetic field so it changes the boundary that we're protected at so different satellites may be more or less protected during one of these events.

This kind of shows the sun and how the magnetic field is being compressed. The yellow fluffy area there is supposed to be one of these coronal mass ejections as it expands through the solar system and impacts Earth. You can see the magnetic field trails off of the screen to the left as it's being compressed and pushed backwards as it's deflecting most of the impact away from us.

But like I said, it isn't perfect, so when we have these strong events and the magnetic field gets compressed, is when we have aurora borealis or the northern lights.

I have not been lucky enough to be able to see these myself, unfortunately. I know a few tricks to try and see them, but you can see them sometimes in Wisconsin. Typically the more north you go the easier it is to see.

They call it the northern lights. They also happen on the southern pole. But they're called the northern lights because since our magnetic field originates from the poles, the north and south pole, that's where a lot of the energy that can get through will funnel back into Earth. I'll end with an animation that shows that process happening a little bit better, but essentially the poles are where that energy will fall into, and the stronger the storm, the stronger the coronal mass ejection that's impacting Earth, the farther down it can push that energy on Earth. If we're ever seeing aurora borealis or the northern lights from Wisconsin, that means that it's being pushed down pretty far south. So what that's telling you is that we're experiencing a pretty significant space weather event here on Earth. So there's no reason to be scared and be running to the emergency room, but it is something to be aware of. If that's happening, people a little bit more north of here, especially if it's somewhere like Alaska, Norway, Scandinavia, they could be experiencing some of the harmful effects that I'll get to soon.

The more south you see these events, the stronger the event, the solar storm that's happening. Like I said, I haven't been lucky enough to see one of these yet. I would love to sometime. One trick that I have learned that has not yet worked for me because I haven't been dedicated enough is, if you're ever taking a red eye flight, especially one that's long, like, say, from here to Europe, if you're flying from here to Europe, try and get a window seat on the left side of the plane and just stare out the window once it's dark for as long as you can. If you can get your eyes settled enough to the dark that is out there, looking towards the north pole, you should really be able to see these all the time.

The stronger the storm the more south these lights come, but essentially it's happening all the time. We just can't see it because it's way up at the poles. The sun always has the solar wind that's like a weak push of material off the atmosphere going out into the solar system, and that's always impacting us and it's not really harmful, but it's still causing these northern lights to happen all of the time, essentially, just very weakly. Almost any time you are flying, you should be able to see it if you go close enough to the north pole on one of those polar routes. If you're dedicated enough to stare for long enough, you might get lucky to see it. It also helps that you're at high altitude, there's going to be no light pollution, except from whatever's inside the plane. I usually just fall asleep if I try and do that too much, so you have to really be dedicated, but I do know people who have done it and successfully been able to see some of these northern lights. Keep that in mind if you're ever taking a long flight sometime soon.

Okay, so like I said, though, unfortunately, space weather isn't all pretty. There are a lot of harmful effects that it can cause. We'll start at the top here. First and foremost, astronauts are in space. They're not as much protected from our atmosphere, from our magnetic fields, as we are down on Earth. If we start off from that first event I was telling you, a solar flare, it emits strong, powerful radiation like x-rays, and that travels to us at the speed of light. We can't predict it, we just see it and that's our first warning sign. X-rays aren't good for us. They can cause mutations in our DNA. If you're an astronaut in space, you're at risk for that extra radiation. Here on the surface, our atmosphere blocks out most of those x-rays and it's not going to cause any harm for us. But the farther and farther you get up in elevation, the more chances there are for those x-rays to reach through and impact us. So if you're an astronaut, say, doing a space walk and servicing the Hubble Space Telescope or anything, and one of these solar flares happens which we can't really predict, you're at more risk for extra radiation absorbed and it's just never a good thing.

Apart from that, the radiation and the intense flight can also just damage satellites. It can damage the solar panels on satellites that are providing their power. That's bad for us here on Earth because those satellites are what give us our GPS signals, our telecommunications.

A lot of our everyday electronics rely on satellite technology, and they could be harmed just initially from the flare itself. Most of the satellites, luckily, are going to be within the protection of our magnetic field. Those keep them generally protected. That's also true for the astronauts. That keeps them generally protected from the biggest part of the impact. Though, like I said, the stronger the storm, the more it's going to compress that magnetic field, and every now and then some of these satellites might poke out beyond the influence of that magnetic field, and that's going to leave them at greater risk for damage. It can actually fry instruments on the satellites, knock out them entirely, and destroy satellites entirely that we may need to heavily depend on. And GPS satellites are especially vulnerable because they are at really high altitudes above so that they can always be stationary above us. The farther up the satellites, the more at risk it can be. Closer down to us, so these events, when they're happening, can cause currents in our atmosphere, and that will interfere with our communications. So if we have radio communications, whether that's communicating with a satellite in space or just radio communications here on the ground, so your FM radios, if you're trying to talk between a plane and ground control, all of that can be affected and disrupted by one of these events.

More kind of everyday life-threatening, I guess, not life-threatening, but a bigger threat to us is on the ground it can also cause currents to flow through the ground without any source. When these powerful events are happening, it's a lot of chaotic magnetic fields, which can induce currents and damage electronics here on the ground. Ultimately what it can do is if you have a really strong storm, it can cause blackouts across the entire country. If you have a strong enough storm, it really could knock out power from DC to California, all throughout continental US. And it's not just like your everyday power outage, it goes out and will come back on. What's causing the ground power outages are actually the transformers being overloaded and essentially frying. You have to replace each and every one of those transformers, which is not an easy task. We don't really have that many spare transformers available. It's just something that, if it were to happen today, would cause ground power outages for weeks or even a month, and you can imagine how devastating that would be, whether it's to your everyday lives. I mean, government infrastructure would have to close down. Hospitals need electricity for their patients. These are some of the reasons why space weather is so important that we keep an eye on it, keep track of it, and try and protect ourselves. There are ways to keep ourselves protected. If we see one of these events happening, we can shut off a lot of our instruments, a lot of our electricity. If we do that ahead of time it can protect all of the transformers and all of the instruments and electronics and computers we have to try and keep them operational as much as possible and limit our impact from the damage.

Okay. Pretty recently, space weather's been picking up a lot more attention, whether that's in the media, within the government. I worked at NASA doing space weather forecasting. My task was to monitor daily real-time conditions from satellites, and when something was happening, so when I detected one of these coronal mass ejections, I'd have to measure what was happening, run a model to predict when it might impact Earth, how severe that impact might be, and then the important part was send out alerts. Those alerts would go out to NASA so that spacecraft operators and our astronauts can be safe. We also send out the alerts to the Air Force and other private industries that operate different spacecraft. The Air Force especially is an interesting forecaster of space weather. They have their own independent team that also monitors space weather 24/7. The reason for that is because during the Cold War, a giant solar storm almost caused a nuclear war. And you might not think that makes much sense, but some of the effects that a space weather event here on Earth can cause can be misinterpreted very easily. It causes chaotic miscommunication, changes in radio signals, ground power outages. Things you might expect if maybe you were getting attacked by someone. In 1967 we really were very close to falsely interpreting a space weather event as the Russians launching nuclear weapons against us. I mean it went as far as the president getting ready to retaliate and strike back. Luckily 1967 was when space weather was starting to develop as a field, and the Air Force was already aware of it and actually starting to monitor the sun. They were able to quickly say, hang on a second, take a step back, we think this isn't a nuclear war. There actually was this big solar flare that happened a couple days ago. It could make sense that that is what's causing this disruption. It turned out to be the case, so we're still here. We can thank the Air Force and their space weather team for that. But it shows just one of the ways why our government is also very interested in space weather and why it's such a valued program.

The internship I had was an NSF-funded internship. The department I worked for is known as the Community Coordinated Modeling Center. It's really just a fancy name put together to express that it's a larger community, more than just NASA that is supporting the activities that they do. So it's funded by NASA. There's actually White House grants that directly go into it. The Air Force and military and also private industries that operate a lot of spacecraft provide the funding for that specific subsection of NASA to operate their space weather forecasting system.

Okay. So what can we really do about space weather? We know that it's happening, I showed you how some of the ways we see it happening, but how can we actually do these forecasts? How can I make these predictions when I see these events happening, and warn someone of the harm that could come? If we think about how we do it on Earth, what we need is data, we need to look at something and get information, and then we need a model, something that we can use to predict what might happen in the future based on the information we know that we've seen or is currently happening. So on Earth, we have weather forecasts. You probably check it every day.

On Earth, we're lucky we have a lot of satellites looking down on Earth, gathering a bunch of data, a bunch of different wavelengths and types and feeding into these models that are predicting wind, pressure, all of these different readings that we have here on Earth. You probably have realized that the weather predictions you get on a daily basis are not that great. So, it's really difficult to do this, and we have a lot of information to go off of when we're looking at weather on the ground here on Earth. You can imagine how difficult it might be with space weather, where we have to predict weather events happening on the sun that, remember, is so ridiculously huge you can't even imagine how big it is. We have to rely on information we're getting from images from spacecraft, which aren't that frequent, and there's also only a limited number of spacecraft that we have that are concentrated on looking at the sun. So really, working with the minimalist amount of data to try and inform our models when we're doing these space weather predictions. But it turns out we still do a pretty good job. There's a lot of improvement that could be done, which is why space weather's such an active area of research today.

What do we have looking out at the sun? Like I said, we really do rely on satellites to get constant 24/7 monitoring of the sun. What this is showing is many different satellites in orbit around Earth. You might notice there are some that are doing standard Earth orbits, some that are really elliptical, some that look really, really funky. There are often pairs of satellites that seem to be traveling together. A lot of those missions are either looking at the sun, looking at Earth, or just kind of monitoring the conditions in space around Earth. Remember, space weather refers to processes in space that affect Earth or the near-Earth environment. A lot of these are going through what we call the magnetosphere, which is that zone of influence of our magnetic field that is protecting us, and getting real-time measurements of how the magnetosphere is behaving, how our magnetic field is actually interacting with the solar wind and these coronal mass ejections as they're impacting Earth and seeing how it's being compressed. There's also a couple satellites we have in orbit around the moon, which are what's on the bottom of the screen now. We have lots of different places to get data. It looks like a lot here, but if you think about how many we have looking at Earth for our regular weather data, it's very, very tiny. One of my favorite satellites is the Solar Dynamics Observatory, SDO. A lot of the best-looking images and animations I've been showing you guys of the sun come from SDO. It's in orbit around Earth. It's always stationed so that it is in communication with one dedicated large radio dish that's in, I believe, New Mexico. It's always talking to Earth, always looking at the sun, sending us pictures every roughly 30 minutes at many different wavelengths. And the reason it's my favorite is because it's looking at the sun at so many different wavelengths. This mosaic of images stitched together is a picture of our sun, but at a bunch of different filters, looking through a bunch of different filters at very specific colors and wavelengths of light. And each different panel there, each different color, is telling us a different piece of information. It's letting us look at a different layer of the sun, a different temperature of gas that's around the sun and probe different events and mechanisms that are happening. Some of these wavelengths are really good for seeing the solar flares happening when it gets really bright and giving our first predictions of what's going to happen. A few of these wavelengths, especially that orange-colored one, are really good for seeing those coronal mass ejections where you can see filaments actually rising off of the surface and going out into space.

All of these are useful for a different purpose, and you really do rely on SDO a lot to do these space weather forecasts. The nice side perk is that it's really high resolution. It gets really good images of the sun, they look great. Makes great posters.

Another really important mission for space weather is what we call the STEREO mission, believe it or not, STEREO is an acronym. I don't actually know exactly what it stands for. I believe the first S is stereo, so it's an embedded acronym within itself. You might notice that astronomers really like acronyms. STEREO-A and STEREO-B here stand for STEREO-Ahead and STEREO-Behind.

What this image is showing is the sun at the center, Earth at the bottom, and STEREO-B and STEREO-A up near the top. The way these satellites were designed is so that they are in orbit around the sun, just like the Earth, but STEREO-A, STEREO-Ahead, is going slightly faster than Earth in orbit. It's slowly leading ahead of Earth in its orbit around the sun. And STEREO-B, STEREO-Behind, is slowly lagging behind Earth and going behind in the orbit. Over time, they've reached towards the other side of the sun and what they're doing is providing us with a 3-D view of our sun. It's letting us look at the sun from many different angles, and instead of just looking at a single image of a circle that we're seeing that I've been showing you for most of the time, this lets us construct a 3-D picture of where on the surface of the sun these explosions and flares are happening, and that's how we can really get the information to try and estimate if these solar flares and these coronal mass ejections are going to be directed towards Earth, if they're going to be directed towards a different planet, if they're just going to miss Earth entirely. It really is instrumental to be able to let us make these predictions.

The center panel might look familiar here. Before I showed it to highlight a coronal mass ejection earlier in animated form.

SOHO is another spacecraft that we rely on heavily for space weather forecasting. SOHO is the only telescope we have that's looking from Earth's perspective at the sun with that disc blocking out and eclipsing the sun so that we can see the faint corona. It's a pretty old satellite, actually. It's about 20 to 25 years old now. There is a fear among the space weather forecasters that if that satellite were to break or malfunction, we really lose our first line of defense. And we really this need kind of imagery to be able to measure how fast these events are happening and how fast the coronal mass ejections are traveling so we can predict when we'll actually get impacted if we're going to. The left and right panel here are from STEREO-B and STEREO-A, a very similar setup of the camera, where you're blocking out the main photosphere of the sun and just seeing the faint atmosphere around it. You can see if you kind of step through time is how you create these movies of these coronal mass ejections happening.

For each different panel, the same coronal mass ejections. You can see that it looks like they're pointed in different directions in all of them, and that's because all three of these satellites are looking at the sun from a different angle. Just like how our GPS satellites need three satellites to triangulate a single position here on Earth, here we have three satellites in space to triangulate a single event, a single explosion off the surface of the sun and triangulate exactly what direction that is headed. That's what lets us input the information we're seeing from the corona into our models and make these predictions.

More recently, you might have heard of the Parker Solar Probe.

This is a very recent satellite that actually just launched on Sunday, around 2:00 a.m. on Sunday from Cape Canaveral.

The kind of tagline for this mission is that it's a mission to touch the sun. And the reason we say that is because it's giving us a new view of the corona by going really close to the sun, as close as we can really get without getting too close. It's going to get up to four million miles from the surface of the sun. I mean, that sounds like it's not that close. Are we really lying, saying we're going to touch the sun? But remember, the atmosphere of the sun, the corona of the sun, is pretty big, it's faint, it's hard for us to actually see unless we block out a lot of the light, and it extends pretty far. So if we go back to one of these images where we see one of these coronal mass ejections happening, four million miles from the surface is roughly around this red ring.

It still seems like it's pretty far, but you can see how a coronal mass ejection is easily very, very close, still at the initial stages where we're making measurements of it happening when it would directly come in contact with the satellite.

The Parker Solar Probe is really a groundbreaking mission to give us insight into what the corona really is and help us explain why these explosions are happening. I've told you guys that they happen, but I haven't really explained why they're happening, other than just kind of mystically saying the magnetic field is causing them. Really, the reason I'm doing that is because we don't have a very good understanding of exactly what's causing them. The corona is also very, very hot, much hotter than the surface of the sun that we can see with visible light. We don't exactly know why it's as hot as it is, so this mission is hopefully going to give us a lot more information to be able to try and understand and disentangle that information.

Once we have all of this information, once we can make these measurements of these coronal mass ejections, look through them, see how everything is changing, we can input them into different models.

This is the modeling interface that NASA actively uses when they make their predictions. There's a lot going on here, but the really important things to pay attention to: the sun is at the center of the image.

Earth is the yellow dots in the different panels. What you're seeing as time goes by, this is going through about 10 days' worth of time. You might see these spiral features going off of the sun in different directions. That's being caused by just the ambient solar wind that we see all the time. They are often concentrated in these little jets that correspond with coronal holes or sunspots that you might be familiar with. They usually aren't causing too much harm. They're just kind of always there. That's why we have these northern lights every night. Just not very strong. When a coronal mass ejection happens, so what's happening, it just went through one. You might notice a little eruption happening off the sun there. That is the input coronal mass ejection based on the measurements that we can make from the images we have, and then it'll travel through the solar system. This one happens to be directed towards Earth, and in about two to three days the model can tell us exactly when we might expect it to impact us, and the model also has information on the magnetic fields that are present near Earth, near the sun, through the coronal mass ejection when it's happening, and that all combined is going to give us a prediction of how severe of an impact we might have here on Earth. This model feeds into what a lot of people might, if you subscribe to those northern light alerts that you can get, or space weather alerts you can get, they come from the result of primarily this model. NASA uses this model. The official space weather broadcasting agency that the government subscribes to is through NOAA, the National Oceanic and Atmospheric Administration. NOAA also uses this model. One of the cool things about my internship was that I worked independently of NOAA through NASA, but we would often collaborate with NOAA, compare our models, compare our results, and that way the government has two very independent sources of information that they can compare where one set of eyes is doing one type of analysis, another set of eyes is doing another type of analysis, and we compare our results and they're usually very, very consistent. NASA is focusing on internal things, so keeping sure NASA missions are safe and the satellites we care about are safe, whereas NOAA is really more concerned about exactly what's happening on Earth and keeping infrastructure on Earth and the government more informed for political reasons and also everyday citizens. And so I'm going to end with one long, drawn out, slow animation. It's essentially going to sum up everything I've talked about, starting all the way from the center of our sun. What's happening here is it's showing an animation of how energy is being created in our sun, and that's through fusion, so it's when two protons or two hydrogen atoms collide together, fuse together. Eventually they'll form helium, and in that process release a lot of energy. And that's what's ultimately powering our sun and providing its energy. Slowly that energy is going to transport its way through the sun, make its way to the surface. Once it reaches closer to the surface, the magnetic field of the sun will start to interact with it, and that's when you'll start to have these loopy materials, these filaments, puffing off of the surface, heating up the atmosphere, the corona, and causing from time to time these massive eruptions. So it's going to walk through a few animations of eruptions, as well as a few actual real-time movies that were put together from SDO data. This is still a computer simulation of the surface.

This is real data. This is taken from the SDO spacecraft, looking at parts of the sun and parts of that corona erupting off because of those magnetic field lines puffing out and breaking off of the surface.

Keep in mind how big these eruptions are. Earth, if I were to put a little Earth dot there, would just be a tiny speck. And these are happening all of the time. Here's a particularly massive eruption off the surface.

And now we can actually see as those eruptions travel through space, they expand, they get bigger, and they eventually turn into these really ominous-looking blobs traveling towards planets in these animations. So here we have Earth as this pale blue dot, and this ominous coronal mass ejection slowly approaching it. As you look at it from a different angle, we can start to see how the magnetic field is there, acting as a shield to redirect a lot of that impact. But you'll notice once the solar storm approaches, that magnetic field will start to get compressed. It will get squeezed inwards a little bit. You'll see it from a few different angles. And this is how some of the energy is going to fall into the poles, and that energy is what's going to light up and provide the northern lights. So as that coronal mass ejection passes through our magnetic field, it's compressing the magnetic field and in that tail end is where you might have some of these magnetic field lines sparking together, just like how they release energy on the surface of the sun. They do the same thing near Earth and then fall into the poles, and that's what's energizing atoms in our atmosphere and lighting up the northern lights that you can see on both poles. And that will conclude my talk. 
(applause)