...what it was like to help build the James Webb Telescope? (with Stephanie Hernandez)

Ever Wonder? / November 24, 2021

...what it was like to help build the James Webb Telescope? (with Stephanie Hernandez)

JWST_Stephanie Hernandez

In the upcoming weeks, NASA will launch the James Webb Space Telescope—the most powerful telescope ever put into space. This $10 billion technical marvel is a complex and massive spacecraft—think of something roughly the size of a tennis court—that scientists and engineers have been working on for decades to explore the deepest reaches of our universe. 

Many experts view Webb as the rightful successor to the Hubble Space Telescope, which launched in 1990 into a low orbit around Earth. When Hubble didn’t work properly, NASA could send astronauts up in a space shuttle to repair it.  

But here’s the tricky part: Webb isn’t going into low Earth orbit. Instead, it will be placed into an orbit about a million miles away from Earth, where there’s no way to reach it after launch. It needs to work right the first time. 

Do you ever wonder what it was like to help build the James Webb Space Telescope? 

Stephanie Hernandez is a systems engineer at Northrop Grumman working on the James Webb Space Telescope. She is part of the team that tests and verifies literally thousands of things on the telescope while it’s on the ground first, to make sure that it will work in space later. Stephanie gave us a peek behind the scenes of what it’s like to work on a such a technologically complex and high-stakes spacecraft, how she got started at Northrop Grumman as a summer intern, and what this whole experience means to her as a first-generation college student.

Celebrate the launch of NASA's newest premiere space science observatory with more virtual activities and events from the California Science Center

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Perry Roth-Johnson (00:06): 

Hello! This is Ever Wonder? from the California Science Center. I'm Perry Roth-Johnson. In the coming weeks, NASA will launch the James Webb Space Telescope—the most powerful telescope ever put into space. This 10 billion dollar technical marvel is a complex and massive spacecraft—think of something roughly the size of a tennis court—that scientists and engineers have been working on for decades to explore the deepest reaches of our universe. Many experts view Webb as the rightful successor to the Hubble Space Telescope, which launched in 1990 into a low orbit around Earth. When Hubble didn't work properly, NASA could just send astronauts up in a space shuttle to repair it. But here's the tricky part: Webb isn't going into low Earth orbit. Instead, it will be placed into an orbit about a million miles away from Earth, where there's no way to reach it after launch. It needs to work right the first time. 

Perry Roth-Johnson (01:01): 

Do you ever wonder what it was like to help build the James Webb Space Telescope? Stephanie Hernandez is a systems engineer at Northrop Grumman working on the James Webb Space Telescope. She's part of the team that tests and verifies literally thousands of things on the telescope while it's on the ground first, to make sure that it will work in space later. Stephanie gave us a peek behind the scenes of what it's like to work on such a technologically complex and high-stakes spacecraft, how she got started at Northrop Grumman as a summer intern, and what this whole experience means to her as a first-generation college student. Take a listen. Stephanie Hernandez, you are a systems engineer at Northrop Grumman working on the James Webb Space Telescope—Stephanie, welcome to the show! 

Stephanie Hernandez (01:49): 

Thank you. Thank you so much for having me. 

Perry Roth-Johnson (01:52): 

Yeah! And Devin Waller, co-host of the show is also here with us. Hi Devin! 

Devin Waller (01:56): 

Hey Perry, good to be here. And hi Stephanie, thanks so much for joining us! 

Perry Roth-Johnson (02:00): 

So Stephanie, we're so excited to talk to an engineer like you, who's worked on the James Webb Space Telescope, which is scheduled to launch this December. A few years ago, you also appeared in a short video series about the Webb Telescope through the eyes of its engineers. Uh, I'm a child of the 90s, so I grew up seeing lots of amazing images and discoveries coming out of the Hubble Space Telescope—large space telescopes have a way of capturing people's imagination, and Webb is definitely a BIG space telescope poised to hunt for even more discoveries about our universe. But before we get into your work on Webb, or the differences between Webb and Hubble, I just want to start with the telescope itself. What is the James Webb Space Telescope. And how do you describe its mission to friends and family? 

Stephanie Hernandez (02:41): 

Yeah. So, well, how I describe James Webb to friends and family—it's, I literally said, a very large telescope that's going to get launched into space a million miles away. Now, if you say a million miles away to anyone even me, it's like, okay, well that sounds really far, but how far really is that? So a few days ago I actually took my goddaughter to see James Webb. And in order to explain to her, I was like, oh, it was like in the late afternoon. So I was like, look up in the sky. Do you see the moon? And then she was like, yeah. And I was like, okay, well, this telescope is going to go inside a rocket. It's going to go to South America and it's going to go four times further than how far you see the moon. And she just stay looking at the sky like, wow, like that's really far. And I was like, yeah, it's going so far. Um, but yeah, it's a large telescope. It's going to get launched out of South America. And it's been an amazing collaboration between the entire world. We've partnered with the European space agency, the Canadian space agency and NASA. So it's very exciting to send something so far away. It has been such a big collaboration, not just like a United States thing. 

Devin Waller (03:48): 

So Stephanie, tell us how long you've been working on the Webb mission. And then what exactly is your role on this project? 

Stephanie Hernandez (03:56): 

Yeah, so I actually started as a summer intern on James Webb. I was finishing off my last year of college. I had one more semester left and I applied for an internship at Northrop Grumman. And I got so lucky to get put on the James Webb space telescope. And then I actually stayed on part-time during my last semester of school and then continued on full-time since then. So I started January, 2017 full-time so it's been a good five years now if I count my internship probably five and a half years, definitely a good while, but I wouldn't change it for the world. 

Devin Waller (04:31): 

So you said you're a systems engineer and I know it's for requirements and verifications, right? Yeah. So what exactly does that mean? Can you explain that and break that down a little bit for us? 

Stephanie Hernandez (04:42): 

Yeah. So my team, like you mentioned is the requirements and verification team. So when I came on board, there's different elements that make up our telescope. There's our spacecraft element, which holds all of electronics. There's our telescope element. And then there's the science instruments element. So I am part of the spacecraft element and we have over 8,000 requirements that we need to verify to make sure that yeah, when we launched this telescope into space, it's going to do all the things that we had planned that it was going to do and it's going to work fine. So we're kind of like that very last check before we launched, like, yep, everything is good. So my team goes one by one through every single one of those requirements understands what the requirements intended to, um, be. And then we like at whether it's test data analyses, anything we could use to prove. Cause we have to prove that yeah, look based on this, um, this like paperwork or this test, we indeed meet this requirement. So we should work in space. So we're kind of like that very last check to make sure every single one of those requirements are met. 

Perry Roth-Johnson (05:48): 

So, uh, I love that, you know, you have so many requirements, 8,000 is a good number to kind of wrap my head around, at least because it, it shows how complex this is even. I mean, it's hard on the audio show to talk about this telescope and have people imagine it. Um, if they haven't already seen a picture of it, but that 8,000 group requirements you have to work, you just shows like how massive an undertaking this is. Uh, can you tell us more about how it was built? Like give us a sense of what it's like to be on the ground at Northrop Grumman, putting this massive telescope together. 

Stephanie Hernandez (06:22): 

It's definitely something incredible to see. We have so many people working on the telescope, there's different teams. So we have what we call like our integration and test team that are working in the actual high bay where their telescope is getting built. You see people in what we call bunny suits, which is basically top to bottom, all suited up to make sure that they don't let any contaminants inside the room so we have so many wonderful people working there, creating the test. And then we also have the other set of people working like the systems engineers, the vehicle engineering team and everybody it's amazing. Cause everybody has to work together, even though we're different teams. I feel like in order to make this work, we have to have so much communication between our different teams. I need to work with like the vehicle engineering team to make sure I understand any, everything technical and then work with the testing team to make sure that my test makes sense. So it's definitely, even though we're all split up in different different teams, there's no way we can get this done with all the massive collaboration we have between everyone. 

Perry Roth-Johnson (07:24): 

So are you wearing a bunny suit some days? Do you get in the high bay? 

Stephanie Hernandez (07:28): 

I've actually only been in there once it's very accessed controlled. Yeah. Only the test engineers mostly get in, but I was very fortunate that I I'm one of my team members took me in. Um, and I will say I, my, a lot of props to the team that goes in there because if sounds really exciting, you know, putting on a suit, going and silencing the telescope, but it's very, uh, it's definitely a process of getting stood up, up and down. I know with COVID, we've understood kind of like doctors with their mask. Yeah. I a hundred percent understand like the technicians now with their face mask on all the time and they're all wrapped around. Like I would not want to have a cold in there. It's definitely. Yeah, definitely appreciate them a lot more now. 

Perry Roth-Johnson (08:11): 

Wow. Wow. And, and just real quickly, give us a sense of how big the high bay is in case somebody doesn't know what a high bay is. 

Stephanie Hernandez (08:18): 

Oh, it's this basically this massive clean room. And literally, I don't know. I'm very bad with like measurements, but I would say maybe like six stories high is like maybe maybe higher enough to fit this ginormous telescope. Um, a funny little story when I was going inside the building my first time, cause it's connected to where the offices are and when I was going in for the first time, it's like, oh your meetings in the second floor. And I was like, great, I'll take the me trying to be active. I was like, I'll take the stairs. So then I go up one floor and there's no door. And then I was like, oh, okay. Maybe I was like in a basement floor. So then I go up one more. There's nothing there. And I go up again and there's nothing. So then now I started getting the questioning. I was okay, let me go back down. Maybe I went wrong, the wrong stairs. And I see my manager ironically and coming up and I was like, where's the second floor. And then she just looks at me like, just keep going up, keep going up. It's going to be a while till you hit the real second floor, but it's because all of it contained the high bay and it's not until you really get to above the tusk, where would they call the second floor? So I learned after that, never take the stairs. 

Devin Waller (09:29): 

So let's talk a little bit about the big picture. Again. We often hear that the web telescope is described as a cosmic time machine. How will it help us see back in time and, and learn about the beginnings of our universe? 

Stephanie Hernandez (09:44): 

Yeah. So James Webb is going to allow us to see longer wave lanes than like for example, Hubble was able to see, and that is what's going to help us peer back and be able to see like how the first galaxies form in our universe. We get to see maybe like the different, um, inside of the different thus clouds and just like the different planetary systems, how they're forming today. 

Perry Roth-Johnson (10:08): 

Another thing we hear a lot, uh, you kind of touched on it earlier. Stephanie is the comparison between the newer and older space telescopes, Webb versus Hubble. What are some things that Webb can do that Hubble couldn't? 

Stephanie Hernandez (10:21): 

Hubble, James Webb, definitely two amazing telescopes. JWST is seen more like the successor of Hubble because there were things that Hubble could not do that James Webb is going to be able to help us with. One of those things is providing that amazing infrared capability. Um, we'll able to see the universe in that and while like Hubble, study's more like the optical and ultraviolet lens, um, Webb will focus more on like the universe in the effort perspective. Um, web is also way bigger than Hubble. Um, we have a much bigger mirror than Hubble and so the larger collecting area from that mirror will also help us, um, see pure back in the, like we were mentioning farther back than Hubble was capable of doing. Um, definitely also Hubble was very close to earth where I'm not sure if you know, but Hubble did not work when we launched it into space. So astronauts had to go in and fix a couple of things in order to get up and running. Unfortunately like I've mentioned previously, James Webb is going a million miles away. Um, can't send astronauts to the L2 orbits. So that's why it's such a crucial mission because unlike Hubble, where we were able to send astronauts to fix any damages with James Webb, we don't have that option. It has to work the very first time. And if it does not work off the bed, that becomes space junk. Right? So that's, to me, that's probably the biggest difference is it's not fixable. So that's why it's so crucial. And I make sure we're so certain that everything's going to work here on the ground before we launched. So, 

Perry Roth-Johnson (11:55): 

And that's where folks like you come in, you know, testing all this stuff on the ground before you launch it, as I'm looking pictures of Webb, you know, just here, my computer screen, once it's fully deployed and operational seems like, and correct me if I'm wrong. There's like two main parts we've talked about has a really big mirror. It's this big golden segmented mirror. And then below the mirror, there's this massive multi-layered kind of silvery sunshade beneath it. And both of these parts have to be carefully unfolded right after launch, once Webb is in space. So I get the mirror, you need a big mirror, so you can gather lots of light and data from the universe. But what about the sunshade? Like why does Webb need such a big folding sunshade to work properly? 

Stephanie Hernandez (12:37): 

Yeah, so we need the sun shield to work very well when we launched the space to deploy correctly and work. And that's because like our infrared cameras are, our instruments need to be very, very, very cold and out of the sun's heat in order to actually function properly. So for social doesn't work, then our instruments and our cameras start heating up. And then, well, there goes all the imaging we were going to get. So one side of the sun shield is going to be extremely cold. And then the other one will be like the hot side where like it gets light. So we a hundred percent need that. And if we want to collect any science data. 

Perry Roth-Johnson (13:14): 

Okay, got it. 

Devin Waller (13:16): 

So the, the side that's going to be in constantly pointing toward the sun is going to be extremely hot. And then the other side will be extremely cold, cold faced out toward the outer parts of the solar system. Wow. 

Perry Roth-Johnson (13:28): 

So a hot mirror is not a happy mirror. 

Stephanie Hernandez (13:31): 


Devin Waller (13:33): 

Not happy. How big is the actual sun? Like if we laid this sun shade out or the entire spacecraft, I guess how much room does it actually physically take up? 

Stephanie Hernandez (13:46): 

Yeah. So the sun shield, when it's fully deployed is the size of like a tennis court. Um, that's kind of how we always describe it. Yeah. It's huge. And you would go to a tennis court. There's no way it can be that big, like, oh yeah. It's that big. I've been lucky enough to be able to go see it when it's fully deployed and it's massive, but he had just think of a big, big tennis score. And that's the size of the sun shield. 

Devin Waller (14:09): 

Stephanie, I want to talk a little bit about you as an engineer. So we recently saw a video for Northrop Grumman's series. It's called, oh, I think Webb telescope through the eyes of its engineers and you are featured and we want to dig into some of the things that you said, because I think, you know, we think a lot of people can really relate. Um, in the video you said, I come from a background where I was never exposed to things like this and I didn't know, didn't know about these things. So can you tell us a little bit about what you meant by that? 

Stephanie Hernandez (14:37): 

Unfortunately, I attended a schools that maybe we didn't have either the funds or maybe not the personnel to have even, um, like teachers really talk about like science or space or we didn't have like any science clubs or math clubs. So growing up there was never really like, oh, here's the space class. So growing up, I was like, oh, all I thought was space, was like, oh, there's the moon. And then there's planets. And that was about it. Oh, and stars. Um, I never really, I guess, learned to appreciate how much or how amazing space is because I wasn't taught that unfortunately. And it wasn't until college. And until I actually got hired in here where I started like learning what James Webb was going to do and had a very, an amazing appreciation for the, like the engineers and scientists out there that work on all these space missions. I think that's when I finally really, really started appreciating. And if there's one thing I always tell myself, I do want to do is go back to schools, talk to the kids. Um, I was part of a club called Society of Hispanic Professional Engineers or SHPE in college. And one of the activities we would do is go back to middle schools and elementary schools and do what we call Noche de Ciencias or like science night. And we would do like little rocket experiments with the kids or anything kind of taught them about science and space. And I would see their faces exciting, like, yeah, the next thing you know, I want to be an astronaut when I grow up. And that was something like I never had, none of my friends would ever say, cause we didn't really know what an astronaut was. So I feel like definitely I want to go back and make sure that not many other kids go through what I do, where yeah. We didn't really get taught any of these things, um, and know that it's possible and that there's a whole world outside our world. 

Devin Waller (16:18): 

Yeah. That's so important. And you, you know, you never know doing things like that is so inspirational, especially to young people who don't get the exposure. 

Stephanie Hernandez (16:27): 

Yeah, definitely. 

Perry Roth-Johnson (16:28): 

When you were a kid, uh, were there certain kinds of science, things that you wish you knew or you wish you had access to? 

Stephanie Hernandez (16:37): 

Uh, I mean, now it's so much easier with the internet, right? People can like YouTube things, google things definitely having something like that would have been nice. But I think just in general, um, I'm a first generation college student, so my parents also didn't really know much about that. So it's not like they were to teach me like, there's this thing called space. So I wish now growing up or like, if I could tell kids something you can do is definitely like, if you're interested in something now that you have the resources to do so look it up, look on Google. Like, what is space? What are planets? What do they consist of, or even students like middle school and high school. I personally didn't know when I was in high school, but companies like north of Grumman, NASA, so many different companies hire high school interns. And you can literally start like as young as being in high school. I remember one of our interns was like a 9th or 10th grader already in there. So definitely look into internships at the company if you're interested in space or engineering, or even if you're just wondering what it's like to work in a company like that, definitely try it out. Use your resources, ask questions and to any other engineer scientists out there, anybody that wants to go back to schools definitely go back, talk to the students, motivate them. Cause they feel like that would something that's very impactful coming from somebody that's done it. Then if you just hear a teacher teaching it to you and you're like, okay, yeah, it's part of the lecture versus someone that's actually doing it. Whether it's engineers, scientists, police, whoever it is being like, oh, I do this for a living. And I feel like it's definitely creates a bigger impact in my opinion. 

Perry Roth-Johnson (18:12): 

That's so great. You know, hearing that you're a first-generation college student working on this amazing project, but you're also taking the time to, you know, let a metaphorical ladder back down and help other people climb up and, and follow after you. Uh, that's a nice segue into the next thing. You know, you said in your video just coming out of college and knowing you get to work on something amazing as James Webb is something you're really proud of. So, uh, I think you touched on this a little bit with an internship leading to it, but how did you nab such a cool job at Northrop Grumman while you were still finishing up your college studies? 

Stephanie Hernandez (18:45): 

Yeah, so like I mentioned previously, I was part of SHPE and they have a national conference every year where you get to go and then different companies go with their booths and interview people. Um, so I was lucky enough to interview with Northrop Grumman. And at first I was actually slated to work in Utah on a different program. And then I ended up talking to a different manager that was here in Redondo Beach. And then we ended up clicking so much and he ended up extending also an offer here. And I was like, oh, well this is more local to home. I'm going to stay here. So I don't have to move away from my family. So then I go there and I show up on the first day he was like, yeah. So I'm going to put you on James Webb. And I had heard about James Webb at these conferences because they would always hold like different workshops and show video that I would all be like, oh my God, the people that work on that are like so lucky, like that's so amazing. I, when he told me that I was like, wait, really me, like, why me? Like, I don't know anything, like, so it kinda, I lucked out definitely. And he paired me with like one of the best people I could ever work for. And I learned so much in through there, but yeah, a part of it was luck maybe a little bit of destiny, but yeah, I became one of the lucky people that I really appreciate it when I was at the conference. 

Devin Waller (20:02): 

Oh my goodness. So Stephanie, as we wrap up, we're all looking forward to Webb's launch this December we're going to be glued to our screens and you know, the world will be rooting for you. So where are you actually going to be when it launches? 

Stephanie Hernandez (20:18): 

Yeah. So I was actually thinking about this the other day. Like, what do I want to do? Right. I know probably people at work want to be at work looking at it, but I also want to experience this with my family. So I was literally thinking about it the other day. Like I think I'm going to have a little like dinner thing at my house where we just all watched the TV together with like my family, my close friends, my goddaughters, just to see an experience that I'm probably going to be crying the whole time of excitement and just nerves, but just having everybody there to witness something I'm very, very proud of, very excited for, I think is how I want to witness it. Um, I can't think of any other way than watching it with my loved ones and seeing how excited I am. 

Devin Waller (20:58): 

Oh, everybody's going to be so excited and happy for you. And so proud of you. So how are you feeling right now about having the opportunity to contribute to such a large and important project like this? I can't say enough how incredible this is. The stakes are high. The world is cheering you on. How does that feel? 

Stephanie Hernandez (21:19): 

Uh, I think it's like a mixture of emotions. I definitely feel so blessed to be able to work on such an amazing project. I'm able to tell my kids one day, like yeah, like, uh, your mom worked on that. Um, so I definitely feel very like blessed and excited and then, but also very nervous, like making sure that I feel like pay extra, extra attention to all the detail in my work to make sure we didn't miss anything. So I definitely do feel like that sense of responsibility. Like, yeah, you just like, you're excited to play a part in this. You also need to be very responsible of your word, make sure that you know, everything's going to work correctly. So it's definitely a mixture of emotions. Excited, blessed, nervous, all of the above. 

Devin Waller (22:02): 

So Stephanie, what else are there any other stories that you'd like to share with us and our listeners? What do you want people to know? 

Stephanie Hernandez (22:09): 

Definitely know to watch our launch. We're now scheduled for December 18, super exciting time. Um, and then I guess just know that anything is possible and if you're truly passionate about something, you can make it happen. Just work hard, stay motivated. I will admit when I started off in college because of like my lack of preparation and like my middle school and high school, I did feel like I didn't belong in engineering. I felt like I was going to fail everybody else in the class seemed to know what was going on. And at some point it's like, well, no, you can also do it. Maybe it might take a little extra steps or maybe extra preparation, extra studying, but you can definitely do it. Um, now I'm more passionate about space, so spread the space for it out. Um, but yeah, I think stay motivated, stay in touch with what's going on with Webb. 

Perry Roth-Johnson (23:05): 

And where can people follow you online and find your work or watch, you know, the Webb launch? 

Stephanie Hernandez (23:12): 

Um, I'm pretty sure it's going to be put out on like actual national TV. Um, if now you can watch it like on the NASA web page on YouTube, I'm sure we're going to be streaming it on YouTube. We have social media platforms on Instagram, Facebook, Twitter on, under NASA web. So follow up with updates there. 

Perry Roth-Johnson (23:30): 

All right. Well, it's been wonderful talking to you best of luck to you and the rest of the Webb team. We're all cheering for you. Hope you have a successful launch. Stephanie, thank you so much for joining us on the show. 

Stephanie Hernandez (23:40): 

Thank you so much for having me. It's been my pleasure. 

Devin Waller (23:43): 

Thanks Stephanie. 

Perry Roth-Johnson (23:45): 

That's our show, and thanks for listening! Until next time, keep wondering. Ever Wonder? from the California Science Center is produced by me, Perry Roth-Johnson, along with Devin Waller and Jennifer Aguirre. Liz Roth-Johnson is our editor. Theme music provided by Michael Nicholas and Pond5. We'll drop new episodes every other Wednesday. If you're a fan of the show, be sure to subscribe and leave us a rating or review on Apple Podcasts. It really helps other people discover our show. Have a question you've been wondering about? Send an email or voice recording to everwonder@californiasciencecenter.org, to tell us what you'd like to hear in future episodes.