Khan Academy Ed Talks with Begoña Vila, PhD - Thursday October 13

Hello and welcome to Ed Talks with Khan Academy. I'm Kristen Deserva, the Chief Learning Officer at Khan Academy, and today I’m excited to welcome Dr. Begonia Villa, who is an astrophysicist and the lead systems engineer for two of the instruments on the James Webb Telescope. She was also the deputy lead for operations during the commissioning of all of the Webb instruments after launch. I'm so excited to have her with us today.

Before we get started, I want to remind you that Khan Academy is a non-profit, and we do rely on donations from folks like you to keep doing the work we're doing. You can go to donate.khanacademy.org to donate and help keep us moving and keep us working toward our mission to provide a free, world-class education for anyone, anywhere. I do want to thank some folks who helped support us during the COVID-19 crisis, including AT&T, General Motors, and Fastly.

Next, if you want to listen to this interview on audio or if you want to listen to other interviews we've done, you can go to Homeroom with Sal, the podcast available wherever you get your podcasts.

And with that, let me welcome Dr. Begonia Villa. Welcome!

Dr. Begonia Villa: “Hello, Kristen! So nice to be here. Thank you for having me!”

Kristen Deserva: “Your education journey — were you always interested in space? How did you start out and how did you get to where you are?”

Dr. Begonia Villa: “Well, I grew up in Spain, and we lived outside a big city, so the skies were very dark. I remember when I was little, I was fascinated by the changing sky at night, right? The different stars, the constellations, and even during the day, you know, the sun and the moon phases. At that time, I didn't know there was a career such as astrophysics that I would be able to do. I did my studies, I was a good student, then I started in physics and followed my degree with my PhD in that field. I progressed from being in the university as a researcher to moving into the private sector, working to build some of these satellites and observatories that we are going to launch and do the systems engineering. That has been my path to get here. It’s great!”

Kristen Deserva: “Were there particular teachers or courses that you really enjoyed or were influential for you?”

Dr. Begonia Villa: “Yes, for sure! I loved all the topics; I think I still do. Obviously, I love physics and math, but I also love history and lots of other things. In those days in Spain, I was going to a Catholic school, and they were all girls, and the teachers were all women. I remember my physics teacher; she was not a nun, but she was a woman. She was attractive, and she was very good at physics, so I think that helped me a little bit to know that being a woman or being a girl, you can combine both things. Later on, once I started in the higher degrees where it was a mixed class with boys and girls, there was also my physics teacher who was really good. I think that's so important, right? When we have these teachers or these people in our lives that are good at what they do and explain things well and we relate to, I think there’s such good encouragement to keep us going on the path we want to pursue. So definitely, I have had good support throughout, which is very lucky.”

Kristen Deserva: “Great! So give us your quick pitch about the James Webb Telescope. What makes it unique?”

Dr. Begonia Villa: “Yes, for sure! It's the largest telescope we have launched into space up to now, and I think it's unique in two ways. It's unique in the engineering part and unique in the science part. On the engineering side, the scientists wanted a telescope that could look back in time to the first galaxies and stars that formed in the universe and see how they changed to become the planet, the galaxy where we live. Also, they wanted to keep looking for life as we know it on other planets. If we talked maybe 50 years ago, we could ask, you know, do you think there are planets around other stars apart from our own? We could have opinions about it. Now we have had some telescopes out there, Kepler and TESS, that have shown yes, other stars have planets. We think now maybe every star has planets. So Webb can continue to look for those planets, but it can move things a little bit forward, which is do those planets have an atmosphere? If they do have an atmosphere, does that atmosphere look like the one from Earth? You know, we still don't know if they have life as we know it, but it's a little bit moving in that direction.

From the science, obviously, there are wonderful discoveries, but to achieve all that, we needed a big mirror to collect more light and be able to see so far back in time. We also needed to look into a particular wavelength—maybe we'll talk about that later—which is called the infrared. It’s not visible light like our eyes see, so infrared is heat. We needed to be able to cool this telescope, so we needed a big sunshield, a bit like a beach umbrella, to keep it cold. Those two, the big mirror and the big sunshield were great concepts, but they didn't fit in the rocket that we had to use for the launch. So Webb is the first telescope that we had to fold to fit in the rocket and open once we are in space to deploy it. So that was a big achievement on the engineering side that opened the path for future missions being able to do the same. I think it's wonderful on both sides, the science and the engineering for this observatory! I love that balance between the two.”

Kristen Deserva: “So tell us about your role. What do you do?”

Dr. Begonia Villa: “Well, so I started with the Canadian Space Agency. This observatory is an international collaboration, which is one of the super cool things about it. It has contributions from Europe, the European Space Agency, NASA, obviously, universities and companies in the U.S., and then contributions from the Canadian Space Agency. So I started in Canada, working on the two instruments that are their contribution. One of them is a science instrument that we call NEARIS, and the other instrument is the Fine Guidance Sensor. So the Fine Guidance Sensor is the one that's going to allow the observatory to point correctly to what it should be in space and then keep the observatory stable. Meaning, when we are taking an image or a spectrum, like when we take a photo with a camera here on the ground, if you’re moving the camera, the picture is not going to look very good. So you have to keep the cameras steady.

So that instrument doesn’t do the science yet, but it keeps the observatory stable. I started working in Canada and when we built what we call the flight model, the final model that’s going to go into space, those are going to be delivered to NASA. I moved to work directly for NASA, which was really a cool, great experience for me. Then I could take a little bit of a bigger role; I could be involved in some of the testing of all the instruments, some of the planning of that testing, and then on the activities needed to commission that observatory once we were in orbit. I have been very lucky to be part of this observatory for 16 years, so I'm very excited that we are where we are now!”

Kristen Deserva: “Yes, you can definitely look back, and I’m sure, on how far you’ve come! It kind of blows my mind to think about holding stability in space. When I think about it, you know, in my head, you think about things kind of floating around. How do you make something stable so you can get a clear picture?”

Dr. Begonia Villa: “Ah, yes! Every observatory that you launch, any satellite, will have these star trackers that keep track of where the stars are in the sky. It will point to a certain position, but then you need to get the accuracy. So what the guidance instrument does is it takes an image of that part of the sky and is looking for a particular star that the catalog from the ground tells us to find. Once you find it, you keep it in that position and keep it super stable.

What we do is we provide the position data for a star very accurately, six times every second. There is an algorithm that keeps checking if we tell you that the position has changed a tiny bit; there is a mirror that’s going to move to bring the position exactly where it should be. We do this 16 times every second. The instruments that take images over a longer period of time can take 10 seconds to take an image, so we are able to keep that precision so they don't even notice any small movement that we catch.

It’s a kind of closed-loop operation where I tell you something and you react to what I tell you, and then I tell you what I see. This process is something we have optimized for Webb. Of course, you have to work if you think about the sky. There are parts of the sky where there are only a few stars, some where there are hundreds of stars, some where the stars are very dim, some where they are very bright. So, we have to take all that into account in the algorithm so you know it works well every time, or as many times as we can on the first attempt.”

Kristen Deserva: “So, it seems like you're doing a combination of engineering and science. Do you think of yourself as being in both of those spaces?”

Dr. Begonia Villa: “Yes, I think I consider myself very lucky because I love astronomy. I love astrophysics—that was kind of my first love, and that's what I pursued in my career where I did my PhD and my research. I was interested in galaxies, right? I was looking at these spiral galaxies, like our own, where you have arms around the center, and the arms are rotating. At that time when I was doing my PhD, we already knew, thanks to another astronomer called Vera Rubin, very famous, that if we were looking at the rotation of those arms, they were moving faster than we expected when you were farther away. That was the first indication that there is some matter in the universe that we don’t know what it is—this dark matter and this dark energy.

I was doing research; I had a postdoctoral position in universities in the United Kingdom. But the problem at that time is it's difficult to find a permanent position in a university. You can do postdoctoral positions for three years and then maybe move to another university. As a family, we moved to Canada, and at that time, it was a more stable option for me to go to the private sector, but I still wanted to be involved in space and research.

I looked for a company that would work on launching observatories for astronomy into space. I believe I have still been able to use my knowledge in astronomy because you have to work with the scientists who want this instrument to know what they need and be able to meet those needs. You appreciate the science, the reasons why you are doing this observatory, and you get equally excited about what we are going to find out. So I consider myself very lucky that I have the astronomy background, but I also was able to grow in this role as a systems engineer where you look at the big picture and how you can make those scientific goals come to life.”

Kristen Deserva: “And maybe for those in the audience, you can think you want to do something when you are younger. I think anything you learn is so exciting that you learn it. But you can change your mind. You can decide, ‘I thought I would love this,’ and you have loved it. But for whatever reason, I'm going to try something new. It’s never lost. I mean, you have knowledge with you and an experience that will probably benefit the next thing you are looking for.

So I think throughout life, all of us kind of move and get to where we are meant to be or what we like to do through different paths. So, I think that's always very important to keep moving forward.”

Dr. Begonia Villa: “Yeah, absolutely! I had someone who told me it's easy to look back and explain the path of how you got to where you are. But sometimes when you're moving forward, it's not always clear where you're going next, but you can keep building on where you are. And sometimes you're looking for something, right? You're looking for an opportunity, and we all have moments where something doesn't materialize. We thought we would really like to do this, and for whatever reason, we don’t get that.

At the time, it's disappointing for sure. But, you know, it's these kinds of things that we save. Something doesn’t happen, and if you pursue and continue, you’ll find something else. And then, as you say, maybe looking back, you'll go, ‘Well, actually, you know I thought I really wanted that, but maybe this other path is good.’ So I know we all get discouraged sometimes through our life, but I think the important thing is to notice and say, ‘Well, that didn't work. Let me try something else.’ And in the long run, as you say, looking back, maybe everything was for the better or even if it didn't seem like it at that time.”

Kristen Deserva: “Absolutely! All right, so let's talk a little bit more about the telescope. You talked about pointing and where it is. How do you decide what to point it at?”

Dr. Begonia Villa: “Hey, that's a very good question! Of course, you have to decide what you're going to study, right? The team that took part in building the observatory has what they call 'guarantee time.' If you were part of the building, the scientists involved will have a bit of time that when you launch, you have these activities that you want to observe, and you will have the time.

But then the rest of the time is for everybody. This is an observatory for the whole world, so anybody can submit a proposal. If you have a great idea, you can say, ‘Well, I want to look at this part of the sky because I know stars are being formed there’ or because I know there are some bending of the light, or I know there are very faraway galaxies there, or maybe I want to look at this particular planet. You will have an interest as an astronomer, so you have to put a proposal, what we call a proposal, and indicate what you would like to observe.

Then there is a team of scientists that will gather all those proposals and decide which ones are worth it, you know, for multiple reasons, which ones will give the better science. Of course, any observatory in space is oversubscribed, and Webb is as well. But those proposals are selected, and then there is another team that coordinates them to observe throughout the year. You don’t want to be moving the observatory, you know, today here and then tomorrow coming back the other way. You want to be as efficient as possible, so there is a team dedicated to that. I will say we have the proposals approved for this year, and we are going to order them such that we are maximizing the observation time for the year.

That was on for the first year, and now just now the proposal request is open for year two, so any astronomers can now submit what they would like to observe, and again, there will be a process to select the best ones.”

Kristen Deserva: “Wow, that is fascinating! We just were showing some of the images that we see, and they look like art coming back! What are some of the things that people are learning from them from the scientific point of view?”

Dr. Begonia Villa: “Absolutely! I know we were— and you know we had launched. The observatory is 1.5 million miles away, four times the distance of the moon, and it took us a month to get there. We had a complicated process where we had to deploy it, and then we had to open those mirrors. Then we had to align the mirrors, turn the instruments on, calibrate, and all together it was six months.

But even during that time to calibrate and align the mirrors, we were taking images to do that, and we could already sense, even without being fully calibrated, how wonderful the images were. We were all waiting, even us, with bated breath for those first images.

You are seeing some of them there. You can see here the Stellar Cliffs, right? This is one of my favorite images, and I think for other people. So we’re looking for places where stars are being formed, right? And those stars, when they form, some of them in this image have not acquired enough mass to start shining yet, but some of them are shining when they start doing the nuclear reaction, like our sun does. Then they generate a lot of energy that pushes the gases around them. You need that gas to form other stars.

So that nebula shows those newborn stars pushing the gas away, but that pushing compresses some of that gas and allows other stars to form. So it's an area of active star formation, and we know some of those stars will have planets forming around them. So, lots to be learned about that place where stars are being formed!

And you saw another image, which was this planetary nebula, this big ring around— a star in the center is actually two stars. That's the opposite end, that's the star that's dying! When a star dies, it dies in this big explosion, which is a supernova, and it generates these rings that we can see on that Saturn Ring Nebula—the one we are seeing now. You can see there all these shock waves that were formed, and this is very important because we know the first stars that formed in the universe were much bigger than our sun, maybe a hundred times more massive.

Those stars at the beginning only had hydrogen and helium in them—that's the elements that were there— a little bit of beryllium. But when they explode in this big supernova, they generate the extra elements that we need—carbon, oxygen, all the elements of the periodic table. So the next stars that are formed have these extra elements, and this is a process that gets repeated for millions and billions of years until we know we need it because we are made of those elements.

When they say we are made of the dust of stars, it's totally true. We needed those first stars over time to give this richness to the medium that eventually allowed us to be here. So all of that is for sure about star formation, star evolution.

You saw that other super cool image, which is the first one that President Biden selected. That is looking back in time to those very old galaxies in there. We have one of the oldest galaxies today that has been found by Webb, which was born or generated only a few million years after the Big Bang. So Webb has found, for now, the oldest galaxy. In that image, we can also see these little arcs, which are kind of what we call lensing—that's starring a galaxy in the background whose light gets bent. So there's that information there.”

Kristen Deserva: “And tell us about the time—we're talking about this being able to see in the past and what that is like.”

Dr. Begonia Villa: “Yeah, we keep saying we can look back in time, right? Which is such a strange thing! So we can look back—you know, there was a Big Bang. The universe was formed first; it was very hot, and nothing could form. Eventually, it cooled down, and we think about 300 million years after that Big Bang it cooled enough that the little particles started to be able to clump together and that eventually led to the formation of the initial galaxies and initial stars, and then evolution started.

But how can we see that? Well, those first stars and galaxies shine and emit light, right? That light has been traveling for billions of years in a universe that is expanding. The universe is stretching. The fact that the universe is expanding means that this light, as it travels, its wavelength stretches.

So when we say the wavelength stretches, it just means it moves on the spectrum of light that we can see; it moves to another part of the spectrum. It moves to the infrared. With our eyes, we can see the visible, right? What we see in the universe with our eyes is this visible part. And in there, you won't see these objects because their light has moved. So that's why Webb was designed to move and look at this infrared part.

When you take a picture there, then you are kind of collecting that light that has been traveling all that time and being able to then take pictures of these very early objects. That picture you take is how those objects were when they emitted that light, which was many billions of years ago. So that's how Webb is able to look back in time in a way!”

Kristen Deserva: “[Laughter] Yeah, that is crazy! Oh my goodness!”

Dr. Begonia Villa: “I know! And, um, yeah, go ahead!”

Kristen Deserva: “I know we have been talking about things that are very far away, but I think lately you have seen that Webb can also look at our solar system, right? We have seen super cool images of Saturn, of Jupiter, and there are some more that are coming out. Webb can also see, which is very important, can see our solar system—anything that's farther away than the Earth—and this is also tricky to do because we design a telescope that wanted to look for very faint things. Now you're looking at something that's in our neighborhood. Those objects are really bright on our cameras, so we have to use a different technique and be able to look at the solar system. And the guidance instrument as well has to do something different, so each of the images looking in our neighborhood versus looking far away requires different systems on the observatory, and that's something that also had to be developed.

You can see now some of those amazing images that are going to help us study where we are, right? This is the solar system that's closer to us, and we are going to learn a lot again about how solar systems like this are being born and some of the moons in our solar system. We know they have ice. Some of the moons in Saturn and Jupiter are icy worlds, and we know where there is water. We know life on Earth started in water, so anywhere we see water is of interest to astrobiologists and others because it's a clue to understand better how we came to be where we are now.”

Kristen Deserva: “So, do you think we're going to find life someplace out there, other than Earth?”

Dr. Begonia Villa: “Well, I think— I mean, we are special. I think Earth is special. We have seen it's not easy to find a planet, and you can see in our solar system we are the only examples. So I do think we are special. But on the other hand, there are billions of stars, and each of them has planets. So I am optimistic that we will find some signs of life on other planets. Of course, they will be very far away, so we need this young generation that are listening to us. We need to be able to travel farther than the solar system, so we need lots of new expertise to take us there. But I do think that somewhere there might be life like we know it in this huge universe that we are part of.”

Kristen Deserva: “Yes! We have a question from YouTube from Mare about how are the new things that we get to learn in astronomy helpful for us? Are there things that we're learning that are, you know, helping us in our lives?”

Dr. Begonia Villa: “Yes, I think there are two parts to this. To be able to go into space, we have to develop lots of technologies that get used on Earth. So these developments that we have on computers, on fonts, some of the materials that we work with on the ground now, and some of the technologies, like LASIK, that we use for correcting eyes, are things that were developed to be able to put things in space that were lighter or that we could communicate better or that we could download lots of data, etc. There are always applications that come down to the Earth that we use every day.

Lots of things that we take for granted now came from our desire to explore space. But also, I believe it’s part of, in my opinion, what we are as humans, right? We want to know. I believe we need to understand our world, where we live, but I think we also want to know how we came here and how we evolved and how we can continue to explore our universe. I think we have explored the Earth, and we continue to do so, but I don’t think we are limited to this Earth only.

So, I think it's very useful to learn all of these things and continue looking forward, advancing our understanding of the universe, like, you know, relativity and lots of things like that that we wouldn't have known unless we are looking at the universe on this bigger scale, and that we are trying to understand. So I think it's important to keep learning, and yeah, at the big side and on the little side as well, on the small world of quantum physics, gravity, and the universe around.”

Kristen Deserva: “Yeah! We have a couple of questions that are kind of related to climate warming. Are there things we can learn about our own atmosphere or things that, you know, on Earth from some of the things that we're learning?”

Dr. Begonia Villa: “Yes! So, of course, I’m talking about a telescope that’s looking for astronomy, you know, the universe—how are things happening? How do things evolve for our solar system, right? How are things interacting? There are many other telescopes launched into space that are looking at our atmosphere, the atmosphere of the Earth, and we share some of their research to do those observations. Of course, those are the ones that we use to monitor the ozone layer, the carbon dioxide, and it is very important that we know this is happening to tell us that we do have to look better after our planet.

We have grown technologically very fast since the first satellite that was launched, Sputnik, which I believe was 1957. In a very short amount of time, we have learned a lot, and the Industrial Revolution as well from the beginning of this century. We have grown a lot, and our planet, I don't think, is designed for this kind of growth. I do think we have to do better to look after the planet where we live because it’s the one we have. We don’t have another. So I think all of these things are always very important to learn and do better on the planet that we have.”

Kristen Deserva: “Yeah! We are already at the half hour, so let me ask one more question. What is something that you're looking forward to or that we might look forward to from the telescope to come?”

Dr. Begonia Villa: “So again, we know the big themes, right? The things that we are studying, and we are seeing these amazing images. I think we are all looking for something that we won’t understand, right? As the scientists keep analyzing the data and taking new data, I think we are looking for this little surprise that maybe will show us something that we don’t understand to start with, but then as we learn, it will show us something new.

I think that has been true of all the big discoveries in astronomy, right? From earlier on where we thought the Earth was the center and everything turned around, and some of those early astronomers were like, ‘I don’t think that’s quite right!’ I mean, there is some data that I’m taking where I don’t think that’s true. They said, ‘Okay, the sun!’ And how we understand how all the planets move, and then some astronomers said, ‘I don’t know, some of those orbits, we’re finding something there that we don’t understand.’ That eventually, we came up with the effect of gravity and relativity.

I think that always happens. I like to mention, you know, I think maybe, you know, this deep image from Hubble, the Deep Field, which is a part of the sky that when we were looking at it from the Earth, it looked dark. There was nothing there. When Hubble was launched, time was allocated to observe it for many days—I think it was about 12 days—to show that if it’s a dark part of the sky where nothing is there. This is a very famous image, the Deep Field image from Hubble! Oh, behold! There are thousands of galaxies there! So we realized that, you know, the universe is not as we think.

I think for Webb, even if great discoveries are going to come, you know, we have found the oldest galaxy to date, and we have found the first exoplanet with Webb as well. There are going to be these wonderful discoveries, but I think we're all looking for something that we don’t quite understand to start with. I think that’s how we learn and put our thinking cap on and think of something new to understand it.”

Kristen Deserva: “Let’s press the end. So much for joining us today! Looking forward to what we're going to learn next!”

Dr. Begonia Villa: “Thank you! Thank you for having me! I want to encourage all the young kids, you know, to pursue whatever you like and take it forward. I didn’t mention it, but an observatory like this one needs mechanical engineering, electrical engineering, software engineering, astronomers, optical engineering. So wherever you feel something that you like, just pursue it! Then you'll become part of great things that you might enjoy. So go forward!”

Kristen Deserva: “Thank you so much, and thanks everyone for joining today! We'll see you next time!”