In The Arena by TechArena - Exploring the Birth of the Universe with the NASA Webb Telescope

Episode Date: September 14, 2023

TechArena host Allyson Klein sits down with NASA’s Matt Greenhouse to discuss the Webb telescope project, a mission he has been working on for decades, and how it will shape our understanding of the birth of the universe, exoplanets, and potentially life beyond Earth.

Welcome to the Tech Arena, featuring authentic discussions between tech's leading innovators and our host, Allison Klein. Now, let's step into the arena. Welcome to the Tech Arena. My name is Alison Klein, and we've got a terrific episode today for you. NASA is back on the Tech Arena. This time, Matt Greenhouse has joined us. He's a project scientist with the James Webb Telescope Project. Welcome to the program, Matt. It's lovely to have you here. Oh, it's great to be here. Thanks for having me. So, Matt, I know that you've been working on the James Webb Project for quite a long time, and obviously James Webb has captivated the attention of the world in terms of the images that it's bringing back of the universe. But can you

just give me a little bit of background on yourself and how you got involved in this exciting program. Well, I joined the Webb Telescope Program in 1997. So it's ended up being my whole career at that point, post the launch in 2009. But it's been a wonderful experience for me. And, you know, we did a pretty good job building it, it's working perfectly. And it's having even more scientific impacts than we imagined when we designed it. Now, new images published by NASA a few weeks ago at the one-year anniversary are breathtaking. You've shown stars being born. You've shown all sorts of interesting things. What are they teaching us about the beginnings of the universe that we didn't know before? Well, it's teaching us a lot about the beginning of the universe, you know, must be significantly incomplete because we're finding galaxies that are more evolved than they should be at their current age,

at least as we interpret it. It's shown us a whole new phenomenon that we have never seen before. We've seen dark matter stars, you know, quite quite remarkable and so it's been really really exciting the the web has given humanity its first high definition view of the infrared universe and so as one can imagine that first view is filled with lots and lots of surprises and fascinating stuff that the science community is just able to dig into now that they have access to the web as a tool. When you look at all of the scientific data that is flowing back to us from the web, how does NASA work with the broader scientific community to take this knowledge and apply it

to various fields of study? And where do you see the broadest impact of that data? Well, the science community really does all the work and all the interpretation. NASA built the facility. And once a year, we solicit observing proposals, proposals on, you know, what to point the telescope at and what extranet to make. We solicit those once a year from the worldwide astronomical community. And then those proposals are peer reviewed. They're reviewed by other scientists in a double blind fashion. And then about a year's worth of observing is selected, you know, each year.

So at any given time, the web has about a year's worth of work in the hopper to be executed. And then when those proposals are executed, the data goes back to the team that proposed them, and they interpret the data, they write up the results. In many cases, the data becomes public as soon as it's taken, so that it's not just the team that proposed the observation that has access to the data in many cases. Now, the web is sitting a million miles away from Earth. What is it like for the team to receive those images from deep space and be the first ones to see the outer reaches of the galaxy? And I'm sure that must be so rewarding for you, having worked on this project since 1997. Yeah, it is very rewarding. And most of what the web sees is things we're seeing for the first time because the tool wasn't available before.

So it's very exciting for everyone that works with the web. The actual experience, apart from the fact that we're seeing things that humanity has never seen, the actual experience is not really that different from using our other facilities, like the Hubble Space Telescope or the Chandra X-ray Telescope. The data is transmitted to Earth by radio transmission. It's received by NASA's Deep Space Network and then transmitted to a science operations center. In our case, it's the Space Telescope Science Institute in Baltimore, Maryland, that receives the data, calibrates it so that it's ready for scientific interpretation, and then it's sent off to the teams, you know,

via the internet. And so that basic experience is common to all of our facilities. Now, I know one of your specialties is infrared spectrography, and a lot of the pictures that we're seeing are actually taken in the infrared wavelength spectrum. Can you talk about why that's important and how we then convert that to something that the human eye can see? Sure. Yeah. Everything we know about the universe comes to us encoded in starlight. And so the job of modern astronomers is to extract that physics information from the starlight to learn about the objects that produce the light. So in order to get all the information, we astronomers need all the light.

However, not all the light penetrates the Earth's atmosphere to reach the surface. Only a relatively small amount of the electromagnetic spectrum, as they call it, the whole spectrum of light that exists in the universe,

only a very narrow bit reaches that exists in the universe, only a very narrow bit reaches the surface of the earth, which is fortunate for us because some of this light is harmful. But our eyes have evolved to just be sensitive to that narrow slice. But there's a lot more light out there that our eyes cannot see. For example, the ultraviolet part of the spectrum, which the Hubble Space Telescope is designed to observe, that's light that is beyond violet. Our eyes can't see it, but your skin could be burned by it if you stay at the beach too long. Similarly, the infrared part of the spectrum lies beyond the red wavelengths that are longer than the red light that our eyes can see.

Our eyes can't see that light, but your skin can sense it. If you hold your hands near a warm stove or a warm radiator, feel the heat. What's happening there is your skin is sensing the infrared light. Now, we've had to design the Webb Telescope to be an infrared telescope because different information about the universe is carried in different parts of the spectrum. So one of the key objectives of the Webb Telescope was to observe the first stars and galaxies

to form after the Big Bang. Those objects emit their light in the ultraviolet part of the spectrum. However, the universe is expanding. And so as that light travels to us through the expanding space of the universe, its wavelength is stretched into the infrared. So to see that light today, one has to build an infrared telescope. And so that was one of the key objectives of the Webb Telescope mission. And that requirement to observe in the infrared comes with lots and lots of difficult engineering requirements that we have to overcome and meet. That's fascinating.

You know, I mentioned the birth of the star image. It was so beautiful. And, you know, just one of those things that just suspends disbelief and brings, at least for me, you know, brings me back to a childlike wonder. When you think about the images that are being shared, and you can see this in the types of publications that are covering the James Webb, it's really captured the imagination of the populace. What do you think this gives in terms of broader understanding of the universe? And you talked about the origins of the universe. And, you know, you talked about the origins of the universe. Is there anything that we've seen and we've learned where we're really surprised by what we're visioning compared to how we understood science prior to the web?

Well, you know, we're just getting started on the science mission. So, you know, scientists, when we get surprised, it means that we have to dig into a problem for a while with lots of different scientists involved. Right now, the Web is showing us a lot of new phenomena that we haven't seen before. But I think one of the exciting things to watch will be the exoplanet work that the web does. It should be very, very exciting as we're on exoplanets to look for chemical species in their atmospheres that are indicative of life. The web will primarily be observing exoplanets that are somewhat larger than the Earth. However, the web can detect water on an exoplanet that's about three times the size of the Earth. And water is very important for the search for extraterrestrial life.

It's not because alien life might get thirsty and need something to drink, but rather for the organic chemistry of life to occur on a planetary scale, one needs to have a liquid solvent available on a planetary scale. And water is what we're most familiar with. And we demonstrated with the web to this point that we can take high quality spectra of exoplanet atmospheres. We've seen some interesting stuff on that front. Sulfur dioxide, for example, which is indicative of photochemistry occurring in the exoplanet's atmosphere. We're going to be seeing a lot of really interesting results from exoplanets. And I think that's an area that many astronomers, myself included, are really excited. That's fantastic. I can't wait to hear more.

Now, you talked about the messages from the web coming back via radio frequencies. Can you talk a little bit about the technology behind their receipt by NASA and how that data is then interpreted? This is the tech arena, so I've got to ask the question, how are you actually interpreting it and what kind of technology is it used? The actual transmitting of the data is not really particularly new technology. Once you know radio transmission, we're using a part of the spectrum called the KA band, which is high frequency band chosen not to interfere with, not to get interference from other uses of the spectrum,

like cell phones and so forth. And this data is transmitted from the web a million miles away, basically every day to an array of giant receiving antennas that exist in various locations around the globe. And that's called the NASA's Deep Space Network. Those antennas receive the very faint radio transmission. These are really, really big dishes. And then that transmission is then, of course, amplified and it's a digital transmission to begin with. And then that is transmitted back to the Science Operations Center via the internet. So no matter what

Earth station around the globe actually receives a signal, and all gets sent to the Space Telescope Science Institute in Baltimore via the internet, where it is pipeline processed to calibrate it, to remove all the instrument effects and so forth, and to yield a product that's ready for scientific interpretation. And then that is archived in the cloud, actually, by the Science Operations Center, and it is subsequently transmitted to the people who need to get it, again, via the internet.

When you look at the next opportunities, you know, you talked about exoplanet research. You talked about this is a long mission. You know, we've known that Hubble has been transmitting for a long time, and we're hoping the same is true for Webb. What are you most excited about that the scientific teams are taking on? And can you share anything about, you talked about that process of peer-reviewed aiming of the telescope, anything in particular that's been decided that you're going to aim at next? We're getting ready to start the third cycle

of this solicitation of observing proposals this fall. And so the strongers around the world are hard at work writing those proposals. We'll be receiving them in the fall and have the selections announced early in the new year. And so we'll have to see what those are, but one could imagine that a lot of the enigmatic results that we've achieved on the first two cycles

will be followed up on the third cycle with a lot of new work to be proposed. The volume of proposals that we receive typically increases as the stage of the program. On the first cycle was during the height of COVID. I think we were lucky that we got the response that we did given that. The second cycle was much, much larger, and I'm sure the third cycle will be larger still. I can't wait to hear about what you guys find. I know that my listenership is very keen on this particular topic, and they probably want to access more information and stay abreast of what NASA is delivering. Matt, where would you send them for more information and to stay on top of what the

web team is delivering? I would send them to our website. We have a really outstanding website on this mission with extensive material for the press. Whenever something interesting happens on the web, we typically have a blog post about it, which is semi-popular level. And we have tools on the website that you can see like what the web is observing right now

and what it'll be observing tomorrow, things like that. So I think we've done a pretty good job and that's where I send people. I'd also put in a plug to your audience that NASA has an excellent citizen science program, where if you're an individual that's really fascinated by this stuff, but you don't want to go through all the trouble to become a get a PhD and become a scientist, but you'd like to join with a research team and work on the data, you can actually do that by applying to NASA's citizen science program. And despite the name of that program, you don't need to be a U.S. citizen

to participate. So I listen to audio only, but I think if you want to Google NASA Citizen Science, you'll get the website right away. That's very cool. I think you've just lit a number of dreams for folks who are listening online. Matt, thank you so much for being on the program. I love this topic. I love what you guys are doing at NASA. It just makes the world a better place. Thank you so much for spending some time with us today. Thank you for having me. Thanks for joining the Tech Arena. Subscribe and engage at our website, thetecharena.net. All content is copyright by The Tech Arena.