1,778 views | 00:11:08
Amber Straughn brings you on her journey from the big sky of her hometown in Arkansas to studying astrophysics at NASA and demonstrates the infrared technology that will be crucial to the discoveries of the future James Webb Space Telescope.
Episode filmed live at the 2015 World Science Festival in New York CIty. The full Cool Jobs program from that year can be viewed online.
Where did we come from? How did we get here? Are we alone in the universe? These are the kinds of big questions that we as astrophysicists get to ask in our day-to-day jobs. And that’s one of the reasons that being an astrophysicist is such a cool job. We get to think about these huge questions that are bigger than just science questions. These are questions that human beings have been asking for millennia. They’re questions that get to the heart of why we as human beings are driven to discover and to explore our surroundings. So one of those big questions is, where do we come from?
People often ask me, how did I get to where I am at NASA today? It’s actually quite a simple story. I grew up in a small rural farming town in Arkansas. The sky was stunningly beautiful. Those stars called my name. They caused me to ask questions like, how many stars are there? What are they like? What are they made of? What’s beyond what I can see. So as an astronomer, one of our primary tools are telescopes. As an astronomer, I’ve been able to use telescopes all across the world. It’s one of the good perks of being an astronomer, is a lot of the world’s biggest telescopes are in beautiful places like Hawaii and Chile. And I’ve been to these telescopes to observe, which is awesome.
But even on the world’s highest mountaintops, there’s still atmosphere. And what astronomers need to do is get above the atmosphere. So one of the great things we’ve been able to do as human beings is put telescopes into space. Of course, that’s one of the primary jobs that NASA does. This year, all across the world, people are celebrating the launch of the Hubble Space Telescope 25 years ago. How many of you in the room are younger than 25? A lot of you. So think about that. Hubble has been in space for your entire lives. That’s pretty remarkable, right? And for the past quarter century, Hubble has been changing the way that we as scientists think about the universe.
It has literally fundamentally changed the way that we understand how the universe works. That’s one of the great things about being an astronomer, is being able to learn about how the universe works. In addition to the awesome science the Hubble has given us, Hubble has given us stunning imagery. The infamous Eagle Nebula shown here, better known as the Pillars of Creation, has shown us how beautiful star formation is. So we know that stars are born inside dust pillars like this. Inside these large pillars of dust, baby stars are being formed inside dusty cocoons. Many of these little stars have planets orbiting around them as well.
So after stars live out their lives, they shine forth in these brilliant star clusters. This star cluster here contains some of the hottest, brightest, biggest stars that we know of as astronomers. By studying images like this, in addition to being beautiful, we’re able to learn about how processes in the universe work. So these past two images that I’ve just shown you, the star cluster and the Pillars of Creation, are both structures within our own Milky Way galaxy, so relatively nearby in a cosmic sense. So our Milky Way galaxy contains a couple of hundred billion stars. That’s a lot, right? Milky Way is pretty big.
If you could stand on a planet at one end of the Milky Way and shine a flashlight across the entire Milky Way galaxy, it would take about 100,000 years for that light to reach across the galaxy. So the Milky Way is huge. But you all probably know, the Milky Way is not our only galaxy. We now know this, there are many other galaxies in the universe as well. As an astronomer, if I had to pick my absolute favorite image that Hubble has ever given us, it would be this next one I’m going to show you. I’m going to ask to bring the lights down so you can really take it in. So the beauty of this image lies in what you’re seeing. So let me tell you what you’re seeing.
This is the Hubble ultra deep field. In this image, Hubble stared at one tiny piece of sky for many, many days. That’s like looking at the universe through a straw. If you held out your pinky finger, you could cover up this tiny little patch of sky. So little bitty piece of sky. And in this tiny patch of sky, Hubble sees 10,000 galaxies. So every point of light that you’re seeing there is an individual galaxy filled with billions of stars. So what Hubble has given us is the size of the universe. Thanks to Hubble and other telescopes like it, we now know that there are hundreds of billions of other galaxies. The universe is vast and it’s filled with beautiful, mysterious things.
So we know that the universe is filled with light, but you don’t have to be an astronomer to know that, right? You go outside on a sunny day like today and it’s obvious the universe is filled with light. But the light that your eyes can see, and most of the light that Hubble sees is only a tiny, tiny part of the whole range of light that exists in the universe. So your eyes are detectors, but you can only see a teeny bit of the light. Okay? The universe is filled with light that’s bluer than the bluest light your eyes can see and filled with light redder than the reddest light that your eyes can see. That light that’s redder than your eyes can see is called infrared light.
So my friend and colleague Laura has joined me on stage here and I’m going to show you all a little bit of what infrared light does. So I’m glowing in infrared light because I have a heat signature. So you all are glowing too. So what you’re seeing with the infrared light here, or the infrared camera, is a whole range of infrared light. So the whiter part that you’re seeing is hotter, the bluer parts are colder. The really great thing about infrared light and how this relates to astronomy is that some of the biggest questions in astronomy today will be answered by looking at the universe in infrared light.
At NASA, right now, we are building a telescope like this. So at NASA, I work on the James Webb Space Telescope, which is pictured here. It looks a little strange, right? It doesn’t look like a normal telescope that you think of as a tube. That’s because it’s different. It will observe the universe in infrared light and help us answer some of the biggest questions in astronomy today. So this telescope is by far the biggest telescope that we’ve ever put into space. This is a full scale model of it. This was actually here at the World Science Festival in 2010. Do any of you remember seeing it in Battery Park? Okay, cool. So we had it here.
This of course is just a model, it’s just steel and plastic, but we are building the real thing at NASA right now. So we’re going to launch this telescope in 2018. So almost all of the hardware has already been built. So the next few years are going to consist of putting those pieces together, testing and retesting, and make sure it works like it’s supposed to once it gets out into space, and then we’ll launch it in 2018 on a rocket. Now this telescope is so big, it’s bigger than any rocket that we have to launch it on. So what we have to do is fold it up and then it unfolds like a transformer once it gets into space. Really cool engineering behind this telescope.
If you want to follow along and watch our progress, and you can even watch a webcam where we’re building it, it’s on our website. It’s jwst.nasa.gov. So jameswebbspacetelescope.nasa.gov. So this telescope we’re building to answer the biggest questions in astronomy. With this telescope, we will be able to see back in time and see the very first galaxies that were born after the Big Bang, over 13 and a half billion years into the past. We’ll also learn more about how galaxies formed and evolved over time. We’ll be able to use that infrared light to peer inside dust clouds to see how those stars are being born. Then we’ll also learn about exoplanets.
So exoplanets are planets that are orbiting other stars outside of our solar system. When we first started thinking about how to build this telescope, we didn’t even know there were exoplanets that really existed, but now we know of thousands of exoplanets that have been confirmed. Much of that is thanks to NASA’s Kepler Telescope, just during the last few years has really revolutionized exoplanet science. In fact, now we know that planets are common. When I was a kid, we didn’t even know of any other exoplanets. But now we know that if you go outside at night and point up to a star, probably has a planet around it. That’s remarkable. That’s a new discovery.
This telescope is going to allow us to study the atmospheres of these planets. So think about what that might mean. With this planet, we might discover a water world. We’re going to learn about these exoplanets that are out there in much greater detail with this telescope. So we’re really, really excited about what’s going on with this telescope at NASA. So building big telescopes like this, we do it by asking these specific questions and building the telescope to answer these very specific science questions. And that’s great. That’s how science progresses. But for me, one of the most exciting things about being an astronomer is knowing that we will find answers to questions that we haven’t even thought to ask yet.
There are undoubtedly things out there that we haven’t thought of that we’ll discover with a big telescope like this. That’s the promise of the universe. The promise of hundreds of billions of galaxies, filled with hundreds of billions of stars, countless planets, and untold mysteries waiting to be discovered. Thanks.