nasa_in_silicon_valley_thomas_barclay.mp3
A conversation with Thomas Barclay, Senior Research Scientist on the Kepler/K2 Mission at NASA’s Ames Research Center in Silicon Valley.
Transcript
Matthew C. Buffington (Host): You are listening to episode five of the NASA in Silicon Valley podcast series. This week in the news, we have a handful to new updates on the Kepler and SOFIA missions. The latest SOFIA story looks at how a particular type of organic molecules could offer clues to the building blocks of life. On the Kepler side, we are looking at rotating and dancing stars and how they can help us understand how stars and planets evolved. We will release audio versions of those stories shortly, so if you are too lazy to go to NASA.gov/Ames to read the updates for yourself, you can sit back and listen to them on this very podcast.
Speaking of Kepler, today’s guest is Tom Barclay, Senior Research Scientist and Director of the Kepler/K2 Guest Observer Office. We go into the work NASA is doing looking into our solar system and beyond and how we can expand the frontiers of knowledge, capability, and opportunity in space. Of course, we also talk a lot about the Kepler mission and the community of scientists sorting through all the data the telescope brings back to Earth. Here is Tom Barclay.
[Music]
Thomas Barclay: Yeah, I guess my journey is slightly unusual. Most people I work with are like, when I was four years old, I looked to the skies, and I wanted to be an astronomer, and I bought a telescope. That really wasn’t me.
I went to do an undergraduate degree in physics, because I thought physics is kind of cool, you get to learn about how things work. It’s really hard. Physics is super hard. And I wasn’t really into hard things when I was doing my undergraduate, I was into bars mostly.
Host: As one is.
Thomas Barclay: And I thought astronomy, that sounds easy. And it was. It was certainly easier than quantum physics, and fun. So, I started doing more and more astronomy during my undergraduate. And then at the end of it, I was like, I don’t want to get a real job, so I went and did a master’s, and then I went and did a Ph.D. I did my Ph.D. in Northern Ireland, and Ireland’s very famous for being green. It’s the emerald isle. That’s because it rains all the time.
Host: Unlike California.
Thomas Barclay: Yeah, and so really, when I was looking where to go next, I wanted to do a cool job, something that’s really fun, something that’s going to excite me. I also wanted to be somewhere that doesn’t rain very much. So I had a map, I printed off a map, and I circled places with rainfall, and I circled places that didn’t rain, and I only applied to places that didn’t rain so much.
Host: So not Seattle, not London.
Thomas Barclay: I applied to Spain, Canary Islands, Arizona, and California. And fortunately, my number one pick, which would be to come to NASA, work on the best mission there is, panned out. Everything worked out.
Host: Cool. How did, did you just apply to a job, or was it like…
Thomas Barclay: Absolutely.
Host: Literally just saw it online, and you’re like, this sounds fun?
Thomas Barclay: Yeah, so in the field of astronomy and astrophysics, there’s a job register that lists all the jobs, and this one was like, this is really cool, because it’s not pure science. It’s doing work to help the community, to help science in a slightly more general way than you doing all the work yourself. So, that appealed to me.
Host: More citizen science.
Thomas Barclay: Or perhaps more serving the community as well as making yourself successful, and that appealed to me. And so, this job seemed perfect.
Host: When you came in, it was for Kepler, it was for the job you’re sitting in right now?
Thomas Barclay: Not quite. I came into a more junior position.
Host: Kind of worked your way up?
Thomas Barclay: Yeah, people moved on, and I was there, and so they’re like, why don’t you do this?
Host: Life tends to work out that way.
Thomas Barclay: Yeah, I’ve been very fortunate. I think the best advice anyone ever gave me was, make your own luck. Give yourself opportunities for things to fall into place.
Host: With the master’s degree and Ph.D., you get everything setup, locked and loaded, so you’re just waiting for that opportunity to hit, and then you’re just right place, right time, it all works. It’s a mix of lucky and making your own luck, I’m sure.
Thomas Barclay: Yeah, I think all the things that work out, it’s nearly always luck. You just happen to be at the right time, the right place, this happened. Some people have a huge plan, but most people it’s a lot of luck involved. But I think people who give themselves opportunities for cool things to happen, something tends to happen that’s cool.
Host: This is one of the cool things of, not only do we have these big satellites and instruments up in space, or even here looking up at the stars and gathering all this data, but not to just hoard it ourselves. This is the cool part about NASA as a part of the federal government, collecting that data and putting it out there and almost crowd-sourcing research. We have people doing it as well, but we also open it up to a whole community of people to look at the data.
Thomas Barclay: I think one of the things I’m passionate about, deeply passionate about, is making the science data that’s collected using literally millions, tens, maybe hundreds of millions of taxpayers money, making it available to anybody who wants to use it, not keeping it the domain of a select group of scientists who were in the right place at the right time.
So the mission I work on now, I think we’ve done a nice job of making sure anybody can access that data. And so, it has resulted in people like citizen scientists, people who do jobs in the real world, not in the world of science, but they do real things. People of them have written, published peer-reviewed academic papers on our data.
Host: Wow. And so, is the community that helped build, it’s a mix of amateur astronomers, I’m sure academics, probably different research institutions, international and national I’d imagine.
Thomas Barclay: Yeah, of course most people working on the data are professional scientists, one flavor or another. A mix of government labs like Ames and places like that, a lot of people in universities. And probably about half of our scientists working on data are overseas. And a lot of people are students, both undergraduate and graduate students. More than half of our papers, papers on the science using our data are written by students, which is I think something we’re really excited by.
Host: That helps foster and building future coworkers.
Thomas Barclay: Yeah, and you know, I think the Kepler mission, which is where I started, what the Kepler’s done a nice job of is they encourage students early on, and then these students now seven, eight, nine, 10 years later are the professors, and they’re huge fans of the mission. And as the mission moves along, we have this built-in community who uses our data, publishes our data, and tells everybody how wonderful what we do is, and that helps us going forward.
Host: Awesome. Going backwards a little bit, because everybody here, we all know the Kepler mission, know the K2 mission, the follow-up. Go backwards and explain a little bit, what is Kepler for people listening who may not know.
Thomas Barclay: Yeah, Kepler, I think Kepler’s for me the most important mission NASA’s done. And other people will disagree, of course.
Host: Slightly biased, but still pretty cool.
Thomas Barclay: Kepler’s job is to find the faction of stars in our galaxy that host habitable or potentially habitable planets. So, Kepler’s found thousands of planets, literally thousands of planets. In 1995, we knew of the planets in our own solar system, and that’s pretty much it.
Host: And there was some skepticism of if they were even, exoplanets even existed.
Thomas Barclay: That’s right, it was extremely skeptical. People didn’t know. And 1995, the first planet around another star was found, and that was just 20 years ago. And now, there’s this increase, increase, and then Kepler launched in 2009 and found thousands of planets. And really, not only found planets that were the size of earth, teaching us that very likely there are many places out there that look like our own planet, or at least superficially. We don’t know anything in-depth yet, but superficially look like our own planet. For me, that’s really exciting. As science moves on, every breakthrough tends to teach us how insignificant our own planet is. Firstly, we know the earth orbits around the sun, the sun orbits around the galaxy, there are many suns — now we know there are many earths.
Host: Start off with very high self-esteem of us, the sun circling around us, then progressively realize how small and smaller and smaller we are.
Thomas Barclay: You know, I like that. I like that it’s giving perspective of where we come from.
Host: Absolutely. So, Kepler’s this giant telescope. It’s circling around the earth.
Thomas Barclay: Around the sun.
Host: Around the sun, okay, and it’s basically looking at a patch of sky. Because it’s funny talking to people outside of NASA as well, where they’ll see the pictures of Pluto that came in last year, or they’ll look at pictures of Mars. Sweet, so exoplanets, planets around other stars, where’s the photos? It’s like, not exactly the same kind of looking. There’s different ways to determine whether or not an exoplanet actually circles around another star.
Thomas Barclay: Yeah, there are many methods, and the method we use is, we wait for a planet to orbit its star, and it goes round, and hope that the line, the plane of the orbit of the planet is lined up with us, so that the planet crosses in front of the star.
Host: Yeah, because it could be above us, we could…
Thomas Barclay: Absolutely. Yeah, so for every one earth-like planet we might find, there are 200 others that don’t line up just right. So, it’s a very low probability to happen. So, the fact that we’ve found thousands, and these events are very rare, tell us that just planets are everywhere.
Host: And it’s basically just looking at that star and staring at it for a long time, waiting for that subtle dip.
Thomas Barclay: Yeah, we wait. So, for an earth, you’d see one transit, one passage in front of a star per year. So, our mission for Kepler lasted four years. So, we’d have seen four dips of earth if we’d been looking for earth.
Host: And I think this is kind of important as it goes into the community that you’re building up, because it’s not like it’s just looking at one star and then moving to another. It’s looking at a patch and almost making a recording. So, after you’ve done that recording, now going back and looking at the tape and trying to find those situations.
Thomas Barclay: Yeah, I think the data we collected is going to be studied for years, decades probably, because there’s so much data in there. And in some ways, this is the way that a lot of science is going, certainly astronomy’s going, is big data. We’re having to deploy a lot of the techniques that are used here in Silicon Valley in the tech world, because we’re collecting enormous quantities of data.
Host: You have to store it, you have to be able to look at it.
Thomas Barclay: Yeah, and you need to mine it, data mine it. There’s a pretty nice path for people who want to move into Silicon Valley from science, because they’re data scientists, very much so.
Host: Oh, wow, trying to comb through all that data. Wow, so talk a little bit about, there was the original Kepler mission that you worked a lot on, looking at a single patch, and then things got interesting as they moved into the next phase.
Thomas Barclay: Yeah, in 2013, we lost the second of four reaction wheels. Reaction wheels are just spinning, heavy disks. They look a little like…
Host: Wheels, maybe?
Thomas Barclay: Dumbbells, almost, if you’re on weights. And they spin around. And so by spinning them at the right speed, you can change the pointing of the spacecraft. You can minutely adjust how the spacecraft is pointing. But you know, we live in a universe that has three dimensions, and with two spinning wheels, you can’t control three dimensions. And so, we were stuck until some of the genius engineers…
Host: Because one of those wheels literally stopped working?
Thomas Barclay: Two of them. Two of the four. So, we started with four, one backup. Two of them stopped working, and so we didn’t have a method to accurately control the spacecraft.
Host: Was it just pointing wherever, just circling around?
Thomas Barclay: Exactly, yeah. We could hold it loosely, but not precise pointing. And then engineers…
Host: They come up with crazy stuff.
Thomas Barclay: The funny thing about engineers, especially working on NASA projects, they spend most of their life being very conservative, because we launch very big, expensive missions, and they have to think of contingencies and they don’t want anything to go wrong. But suddenly we had a mission that didn’t work, and there were basically no rules. If you could find a method to do something interesting, do it.
Host: Because you had this multi-million dollar, you have this huge telescope. You went through all the effort to put the thing in space, and then great for four years and then these things stopped working. It’s like, we got it up there, what can we do with this?
Thomas Barclay: Yeah, and you see these engineers suddenly…
Host: Creative thinking.
Thomas Barclay: They’re like, this is what I was trained to do, this is what I dreamed of doing, and they’re bright-eyes, and they get to come up with methods of pointing the spacecraft. And so, the one that won out was to use two wheels to control two axes of the spacecraft, what we call pitch and yaw. If you think of the spacecraft as a soda can, pitch and yaw are the up-and-down and left-and-right of the soda can looking out at one direction. But that left a free axis, and that would be the roll, that would be the spinning of the soda can in your hands around the circular side.
So, how do you control that? And the method to control it is, the spacecraft has a shape, and it’s kind of symmetrical almost, if you look at it in that direction. So, what’s causing the spacecraft to not point accurately? What’s making it roll? And that’s the sun. The sun itself is sending out a lot of energy, a lot of particles, a lot of photons, mostly it’s particles. And those, we call this a solar wind, and this solar wind is trying to push the spacecraft away from where it wants to point. But, by balancing the spacecraft against this solar wind, solar pressure, you can keep it in stable pointing.
Host: So you have the two wheels, they’re keeping at least two points, but it keeps spinning around, but if you get it in the right way, you can take advantage of the force the sun exerts to stabilize.
Thomas Barclay: That’s right, and that’s what you’re doing. This is not entirely stable, so once we start to roll away from the thing, that will start to accelerate. This is an equilibrium, but it’s not entirely stable. So, we can hold this for a few hours, and then it starts to roll away. So, we fire a thruster to put us back.
Host: To pull it back.
Thomas Barclay: Pull it back, and this is how we go. So, what we do is we point it at a field for roughly three months, and every six hours or so we fire a thruster to pull us back, and then we slowly roll away, fire a thruster, it puts us back to where we want to be. And this keeps us pointing extremely accurately for a long, long time.
Host: And that’s huge, because even, because the original Kepler mission as meant to look at a patch of sky. I remember talking to someone, saying it’s almost if you hold your hand into the sky, and as many stars as your hand would cover up is about the patch of sky of the original Kepler. But now, you’re almost looking at an arc. You’re looking at several patches of sky, you’d say.
Thomas Barclay: That’s exactly right. We’re looking into what we’d call in astronomy the ecliptic plane. This is this kind of circle, this plane. It’s where all the planets orbit, it’s where the earth goes around the sun, its’ where Jupiter and Mars and Saturn, all these are on the same plane. We call it the plane of the solar system. This just happens to be, this is how we balance things, because Kepler also orbits in the solar system. And so, we look out and we can keep pointing it somewhere for three months. So, we’re currently in our tenth of these three-month campaigns. And so, we’ve looked at 10 times the area that Kepler’s original mission was able to look at.
Host: Wow. And so, are we still getting that data? It’s a continual stream of data that you’re feeding off for the community to then look at, and also NASA scientists also look at?
Thomas Barclay: Absolutely. So yeah, lots of NASA scientists and lots of the community all looking at this same data, doing all sorts of different science. Searching for exoplanets is obviously still a key thing we do, but we do all sorts of science — studying the very youngest stars, studying how stars ae born, and looking also at galaxies, studying supernova from galaxies, really this huge range of science from the very youngest to this very distant.
Host: And it’s cool, because taking that data and you mix that along with other land telescopes, other instrumentation, and you can start cross-checking each other’s data, or find stuff that maybe one mission on its own wouldn’t have known about, but then all of them combined can find new things.
Thomas Barclay: Yeah, actually, we’ve just finished this experiment; it finished just a few weeks ago, which we called the K2 microlensing experiment. Microlensing is a relatively complex idea, but basically the idea is, you have a background star and then you have a star that’s much closer to us, and that passes in front of the background star and acts as a lens.
Host: Because gravity kind of warps that light?
Thomas Barclay: Exactly, yeah. The foreground star, this nearest star, passes across a background star, warps the light coming from the background star, and focuses it toward us. And so, as the planet or the star passes in front, it makes that background star appear brighter for a short amount of time.
Host: You can see it as it goes across warp slightly, and then goes on its way.
Thomas Barclay: That’s right. Now, what’s exciting is if this star has a planet, you wouldn’t see two bright, one brightening, you’d see two, you’d see a second little peek that’s caused by a planet. So, the goal of this experiment was to search for microlensing events from planets, and why — people have been doing this from the earth, there’ve been some wonderful experiments from the earth, but why do it from Kepler, or from the K2 mission is that earth sees these events, the spacecraft sees these events. This line of sight, the angle that earth and the spacecraft Kepler look at the events is slightly different.
And because these events, these lensing events are very finely-tuned to the angle you look at something at, they look different from these two different viewpoints. And so, by using mathematical models of what the events look like from the two different places, you can determine uniquely the masses of things, how much things weight. And so usually you get maybe a ratio of the mass of the lens star to the lens planet, but this you uniquely determine the mass of the planet.
Host: Oh, wow. Can it also tell what type of planet, kind of like rocky or gas planets, or is it kind of…
Thomas Barclay: A little bit, but it’s mostly mass here. You can tell a lot from the mass of the planet. You know something with the mass of Jupiter is probably gassy, something with the mass of earth is probably rocky. Most of the things we’d find here are going to be Jupiter-like.
Host: Okay. Bigger target?
Thomas Barclay: Yeah, but this is really exciting. What Kepler did, Kepler was really just sensitive to inner solar systems or inner planetary systems. It couldn’t find anything that would be exterior…
Host: Further out? It couldn’t find a Saturn or Uranus.
Thomas Barclay: Yeah, it’s just simply not sensitive to those. Why microlensing’s great is, it’s much more sensitive to planets that are far from their stars. So, things like Jupiter, true Jupiters, microlensing is great at detecting. Things like Uranus and Neptune, things further out, it can detect. So, the Kepler mission told us huge amounts of information about close-in planets. Microlensing is a great companion to that, because it tells us about the outer planetary systems. And we get a true picture of what do planetary systems orbiting far from our own look like?
Host: So, for the folks who are listening who are like, exoplanets sound pretty cool, where can they find most of the information, or find a lot of the stuff you’re working on?
Thomas Barclay: NASA does a great job of really explaining things. There’s a NASA exploration program, exoplanet exploration program run by NASA which includes huge amounts of resources just to learn about what’s going on.
Host: Oh wow, cool. Thank you so much for coming around.
Thomas Barclay: Hey, no worries, it’s great to be here.
Host: This is great. I’m sure we’ll have you back many times to go into more details. We haven’t even scratched the surface.
Thomas Barclay: Yeah, it’s such an exciting topic. Actually, why I love exoplanets is it’s so new. We’re such a young science and young field that from month to month there is new discoveries and new information, and what you might say this month will be stale in two months’ time. And what we thought it’s almost certainty we’ll prove to be completely wrong in just maybe a year or two. And for me, that’s what science is, is this dynamic, evolving field that we know now isn’t what we know in the future.
Host: Dynamic, fun, and also job security. There will always be work for you.
Thomas Barclay: Yeah, until we solve it all.
Host: Excellent. Thanks a lot, Tom.
Thomas Barclay: Thanks.
[End]