Dan: 0:00

Swati Mohan grew up watching Star Trek, The Next Generation.

Swati: 0:05

The first episode that I remember seeing was they went to this part of the universe that they fundamentally didn't have knowledge of how the rules of physics applied to. Right?

Captain Picard: 0:16

But where is this place?

Data: 0:20

Where none have gone before.

Dan: 0:22

She imagined herself sitting on the bridge of the Starship Enterprise. What would it be like to boldly go where no one has gone before?

Swati: 0:35

And then I kind of put it aside for a long time because it was fiction, right, like 24th century fiction, like, that doesn't exist.

Dan: 0:41

But the gravitational pull of space exploration never quite let her go. After earning a PhD in aerospace engineering at MIT, she eventually landed at the Jet Propulsion Lab. And decades after she fell in love with space as a nine year old, she was part of the navigation team that successfully landed the Perseverance rover on Mars in 2021.

Swati: 1:06

And I'm counting down landing of, like, you know, five minutes to impact, right, ten minutes to impact, and I just had this surreal feeling of, like, of everything this is probably as close to what it feels like to really be on the bridge of the Enterprise. Because we were literally going out to seek the unknown, to search out life elsewhere in the solar system. So it kinda came full circle to that eight year old and nine year old who got into space first time by watching Star Trek and wanting to be on the verge of the Enterprise and then being in mission control. Was like, that's probably the closest you could actually get to a real life job that does the equivalent of that in this generation.

Dan: 1:49

What do you think the nine year old version of you would think if she could see where you ended up?

Swati: 1:56

I think she would be super excited.

Dan: 2:09

I'm Dan Heath, and this is What It's Like to Be. In every episode, we walk in the shoes of someone from a different profession, a marine biologist, an ice cream truck driver, an aircraft carrier commander. We wanna know what they do all day at work. Today, we'll ask Swati Mohan what it's like to be an aerospace engineer. We'll talk about what it means to live on Mars time, why you need to measure the bug count of spacecraft components, and also the very latest on whether there was ever life on Mars. Stay with us. On the Perseverance rover team, Swati was part of the GNC group. That stands for guidance, navigation, and controls.

Swati: 2:58

Guidance, navigation, and controls is like the eyes and ears of the spacecraft. You can kinda think of the different teams as parts of the body. Right? So you have the mechanical team, which deals with a lot of structures. So that's like the skeletal system. You have the thermal team that deals with fluid loops and keeping hot and cold. It's kind of like the circulatory system of the body. You have the flight software team who writes the code, so that's kind of like the logic part of the brain. You have the mobility team who's responsible for, like, the driving or the manipulators. It's kind of like your hands and feet.

Dan: 3:32

Mhmm.

Swati: 3:32

And then you have, like, the avionics team that's responsible for the computer. That's kind of like the brain itself of the human body. So all of these different parts have to come together, and they have to work super in sync to achieve one of these complicated maneuvers.

Dan: 3:47

Swati breaks missions into three phases, early stage prototyping and planning, then building the spacecraft, and finally, operations when the spacecraft is actually up and running in space.

Swati: 4:00

Operations for me is most gratifying having gone through all the architecture and the development to get to that stage. Because it's kind of the endgame of you did all this work to imagine the spacecraft. You did all this hard work to build the spacecraft, and now to see it doing what you had intended to do, especially when it does it successfully, Something very gratifying about that.

Dan: 4:26

And getting to that point of seeing your spacecraft make it to outer space is a long winding path involving hundreds and hundreds of meetings, sometimes contentious meetings.

Swati: 4:39

The thing with engineering design, especially for these super complicated missions, is there's no right answer. People think especially in school, we're taught, you know, solve this problem and there is a right answer and you just have to find it. In engineering design, there is no right answer. The design itself is as unique as the people who are doing the design. So when you get into these situations where something is not working, you have to make a decision because of x y z schedule constraints. And two people have their own views, or two groups have their own views, and they have extremely valid rationales for their perspective and and their reasoning, but they're at odds with each other. And it's not that either one is wrong. It's just they're worried about different things, about how the mission is gonna work or how the data is gonna be used, and somebody has to make a call.

Dan: 5:34

It seems like with missions of the scale and complexity that you've worked on, you're having to get to those moments 10,000 times, you know, these little compromises that aren't perfect, that aren't optimal, but that are forced on you by resources or timelines or disagreements that that can't possibly be pinned down completely. Is that right? Do you feel like you're kinda having to constantly make informed compromises along the way?

Swati: 6:01

Absolutely. I remember one particular instance when we were building Perseverance where there was a an error in the code, and I like, I knew it was there, but I hadn't quite gotten around to formally debugging it. I was like, I'll get to it. I'll get to it. And then time ran out. And they're like, no. We can't make any changes. So like, but I didn't get to fixing this one. They're like, too bad. Like, it's not important enough for us to fix. So then in operations, I had to do all these shenanigans to work around this problem that I knew was in there, but just because of my own schedule constraints and the amount of work that I had and how I had to prioritize hadn't gotten around to fixing.

Dan: 6:38

That seems like an interesting psychological pickle. Like like, did you know that that error was sort of like, its blast radius was pretty confined? Like, even if it did mess up, it wasn't gonna be of, you know, huge significance? Or do little errors like that sometimes spin out and endanger the mission?

Swati: 6:57

That particular error, I knew that its impact was pretty low. It was more of a nuisance than an actual issue, which was exactly why it was prioritized lower on my list to fix because I was doing the other things first. We do occasionally get the big errors that do cause a big impact. But for those, especially when we can argue that the impact is high enough, that's when we stand up other teams to go and fix. Because it's always a risk trade of, are you gonna add risk in the system because you're opening it up and you're trying to change something? Or is the thing that you found so risky that you're better off taking the risk of opening up because knowing what's in there is much worse than the small chance that you would break something by trying to fix it.

Dan: 7:46

Oh, that's super... I I hadn't thought of that, but you're saying that there's a lot of times when the cure may be worse than the disease. Like...

Swati: 7:53

Yes.

Dan: 7:53

Going and tinkering to fix one problem may cause another one, and then there's a kind of ripple effect.

Swati: 7:59

Exactly. It's not unlike surgery. Right? Like, you have a small mole. Do you wanna get it removed? Probably not because it's cosmetic, and it's not there, and going through the onus of scheduling an operation or whatever to get it out is not worth the cost than living with it.

Dan: 8:14

Mhmm.

Swati: 8:14

But then you discover a tumor, and you're like, oh, crap. No. This has serious implications because it's a ticking time bomb in there. And in that case, like, no. You need to go and fix it. And those are the trades that we're always making every time we find another issue of how do we do that risk trade. And again, it goes back to who are the people and how worried about that particular issue are they in order to make those calls.

Dan: 8:39

The Perseverance rover was the fifth to land on Mars. The first was Sojourner way back in 1997, shoebox size. Its mission, to figure out if you could land and drive on Mars, a technology test. Short answer, yes. It was possible. In 2004, twin rovers Spirit and Opportunity, both about the size of a golf cart, were sent to figure out was there ever liquid water on Mars. Answer again, yes. Incredible. Then the Curiosity rover in 2012 to study was Mars ever habitable. The answer again, yes. The next step was the Perseverance rover.

Swati: 9:24

So Perseverance was really sent to look for the fossil evidence that could hold the signs that there was past life on Mars. Perseverance is not huge. It's roughly the size of a mini SUV. It has six wheels, and it has this mast on the front and cameras on the mast, so it kind of looks like a wheeled robot with a WALL E type eye system.

Dan: 9:51

It's made up of thousands of parts, parts that Swati helped design and build. She told me about one part in particular that had failed repeated tests. Then one day, they tried it again, and they got to the point where things usually went wrong.

Swati: 10:07

And we got to that point, and the data is still scrolling. I'm like, wait. Where did it go? Where did the stops go? And we we just look at each other, and like, it worked. It actually worked? And we're like, oh my gosh. And we just, like, jumped up and down because we, "A", did not believe it was gonna work because it hadn't worked for, like, months ahead of time. And "B", that was our first successful landing with this new part in, which we needed for actually getting to Mars. And that was the first time that we had run kind of everything that we needed end to end where the architecture had held, and it was a successful landing. Like, this was, like, the Friday before Christmas before everyone was going off on the winter breaks. So that moment of, like, it's actually successful, like, all the pieces are there, like, oh my god. This will work. We can actually get to Mars on our landing date out.

Dan: 10:53

Well, that makes me curious, actually. So it seems like those kind of positive surprises might be comparatively rare. Like, if you have 10 surprises as an aerospace engineer, how many are bad surprises and how many are good surprises?

Swati: 11:08

Yeah. Probably one in 10 or one in 20 or something like that are the positive surprises. That's probably why it, like, sticks out the most to me.

Dan: 11:17

So is patience among the number one trait you need as an aerospace engineer?

Swati: 11:23

I would say perseverance is actually more of the traits. It's not just patience. It's being willing to slog through consistently over a long period of time to fix those errors and keep trying.

Dan: 11:36

Yeah. Because patience is a little bit passive. Right?

Swati: 11:39

Exactly. Because you're not just being patient and waiting on the side for someone else to go fix it. Like, you actually have to get in there and keep trying, keep doing, keep fixing one thing after another to get all the way to the end, both in terms of, like, building the spacecraft, but also career wise too. Like, it's not a short hop and the missions, especially to some of the outer planets, they take a long time. Like, we can't speed up physics, so you have to be willing to put in that perseverance to get it to that stage.

Dan: 12:13

After the break, Perseverance lands on Mars. Stay with us. Hey, folks. Dan here. Just wanted to say a huge thanks to all of you who sent us suggestions for the upcoming airport series. The hardest part of making the show is finding the guests. Because we're not looking for celebrities and influencers and top executives, we're looking for people who are doing amazing work but maybe a little bit quietly. So thanks for helping us find them. We're planning to roll out the airport series in the summer, but for now, back to the show. For the Perseverance rover to ever reach Mars, it has to survive an almost unbelievable gauntlet of challenges.

Swati: 13:13

So Perseverance and its predecessors were direct entry, which means we launch straight out of the Earth Moon system. We take just a half turn around the solar system, and we go straight into Mars. There's no slowing down. There's no getting into orbit around Mars first. We kind of shot a bullet, and it goes straight into Mars.

Dan: 13:33

It's a bullet that travels for six to seven months to arrive at its destination. The most harrowing part of the journey is what's known as the seven minutes of terror. Seven minutes. That's how long it takes for the spacecraft to go from the top of Mars atmosphere to the ground, all by itself, no hands on guidance from mission control.

Swati: 13:55

It is the epitome of autonomy because in that seven minutes, we go from something like 5.2 kilometers per second down to zero.

Dan: 14:07

What's 5.2 kilometers per sec? Is there a miles per hour ballpark?

Swati: 14:12

Something like 13,000 miles per hour.

Dan: 14:14

Oh, wow. Okay. Yeah.

Swati: 14:16

It's super fast in terms of miles per hour. It heats up to close to the surface of the sun, the heat shield, several thousand degrees, and then you're jettisoning multiple parts of the spacecraft. So you're firing these bombs, basically, pyrotechnics to explode parts of the spacecraft off. Seven different configurations, something like a 180 pyrotechnic devices, these little bombs that are going off.

Dan: 14:43

So really not much that can go wrong here.

Swati: 14:45

Yeah. 500,000 lines of code or more, and no room for error. Any one thing that happens can be game over.

Dan: 14:54

It's called the seven minutes of terror not only because of the obvious risks, but also because back at mission control, all the team can do is wait. Because given the huge distance between the rover and mission control, every communication back and forth takes a long time to arrive. For Perseverance, it was about eleven minutes that it took for light to travel from Mars Earth, which means as soon

Swati: 15:20

as we hear that Perseverance is at the top of the atmosphere, that would have been eleven minutes ago by the time we actually hear in mission control

Dan: 15:29

Right, right.

Swati: 15:29

That Perseverance has hit the top of the atmosphere, which means, in actuality, it's already on the ground for minutes, whether on the ground safely or whether on the ground, like, in a big pile of flaming scrap metal. It's already on the ground. So the seven minutes of terror refers to we are waiting that entire seven minutes to hear what has happened, but we have absolutely no control or no outcome that we can change because it's already happened.

Dan: 15:57

And you're just sitting there waiting to hear whether your child survived, basically.

Swati: 16:02

Exactly. I worked on Perseverance for eight years for those roughly eight minutes.

Dan: 16:09

If you watched the landing, and if you haven't, you should. We'll link to it. Swati was the engineer you heard calling milestone as Perseverance closed in on Mars.

Swati (archival): 16:20

We have confirmation of entry interface. Perseverance is currently going 5.3 kilometers per second at an altitude of about a 120 kilometers from the surface of Mars.

Swati: 16:34

I think I had a bit of dissociation in that moment because I was hyper focused. Right? That was the only way to actually get through that time period.

Swati (archival): 16:47

Once there is enough atmosphere, it will start controlling its path to the landing target.

Swati: 16:54

We had practiced so many different times. We had prepared for that moment. So I knew what I had to do, and I had seen the data in multiple practice runs before.

Swati (archival): 17:05

Our current velocity is about 5.36 kilometers per second and an altitude of about 67 kilometers from the surface.

Swati: 17:16

So on that day of it was, I would say, almost hyper focused for me

Dan: 17:21

Mm.

Swati: 17:21

Actually calling through what needed to happen.

Swati (archival): 17:24

Perseverance is going about one kilometers per second at an altitude of about 16 kilometers from the surface of Mars.

Swati: 17:33

I wasn't thinking of the implications, really. It was

Dan: 17:37

Yeah.

Swati: 17:38

Can I get to the next step? Are we at the next step?

Swati (archival): 17:41

Our current velocity is about 550 meters per second at an altitude of about 15 kilometers from the surface. Nine and a half kilometers above the surface. 2.6 kilometers from the surface of Mars. Current speed is about 30 meters per second, altitude of about 300 meters off the surface of Mars.

Swati: 18:06

It wasn't until that final moment where I called touchdown confirmed. You can hear my my voice wobbling a little bit at that stage.

Swati (archival): 18:18

Touchdown confirmed.

Swati: 18:30

That's when it actually hit. I'm like, it's it's done and it's safe. That was what we had worked eight years for to get onto the surface safely. And at that point, it really hit home that it was done.

Swati (archival): 18:44

Perseverance is continuing to transmit direct through Mars Recon Orbiter to Earth.

Dan: 18:58

That moment, I mean, just watching that, it just, it gave me goosebumps. I mean, it is just an absolutely incredible I mean, it has to be one of the best moments of your life.

Swati: 19:10

Absolutely. One of the the best moments of my life, especially professionally speaking. I don't... I don't know what else it could take to top that at this point.

Dan: 19:19

I mean, in an alternate reality where perseverance burned up, you know, in the Mars atmosphere, and then you find out seven minutes later, it's it's over, Do you feel like you were ready for that contingency? Like, had you thought about that?

Swati: 19:37

We had definitely thought about it. I actually did have a... because I was the voice. Right? So something happened, like, I had to say something first or not say something first. So I had a whole flow diagram of depending on what information we saw back, at what point do I stop talking, and at what point do people, like, turn over to the other managers?

Dan: 20:01

Wow.

Swati: 20:01

Emotionally, I would say I was not at all prepared for that outcome. That week, everything had been going smoothly, but it definitely felt like every day that passed, the tension and, like, the stress kind of ratcheted up even more because it gave us less and less time to react. And there was some of this growing, oh, things are going too well. Like, is a shoe about to drop and cause the whole thing to go sideways?

Dan: 20:30

Isn't that interesting? I mean, these are some of the smartest analytical people on Earth, and you're starting to feel superstitious. You're like, is this going too well? Are these numbers too good?

Swati: 20:40

Part of that was because we knew where every single one of the flaws were

Dan: 20:46

Right.

Swati: 20:47

In that spacecraft. So you knew too much of the things that could go wrong. Because we've been testing this for eight years. We knew every single one of the fixes that we chose not to fix because of our choice that the risk of fixing it was not as high as the fix itself. And every one of those, at this point were ringing in my ear of, like, what if you had just argued more to fix that thing? What if that's the thing that it was your choice not to fix, and that's the thing that kills us?

Dan: 21:17

Perseverance landed in Jezero Crater, which looks like an ancient lake bed. If life ever took hold on Mars, this is where you'd want to look. So for the last five years, Perseverance has been collecting samples, cylindrical tubes of rock that are drilled out of the Martian landscape. One complication for the engineers back on Earth though, was that to get the most out of the rover, they had to switch to Mars time.

Swati: 21:43

So Mars time is slightly longer than Earth time, and this is because the rotation of Mars is kinda similar to Earth, but it's just a little bit longer. So if you're going on a Mars day, every day on Earth, it just doesn't quite add up.

Dan: 21:59

A day on Mars is about forty minutes longer than a day on Earth. So if you want to work while there's daylight on Mars, maybe one day your shift starts at 7.30AM, and then the next day, it shifts to 8.10, and then 08.50, and so forth until...

Swati: 22:17

Eventually, your day will be entirely switched from Earth. So you'll be working daytime on Mars, which now will be nighttime on Earth. And it just get it's this, like, slow cadence of your off sync and working nights instead of days.

Dan: 22:33

But no matter when the engineers work, the question of whether life existed on Mars can't be answered by Perseverance collecting samples on its own.

Swati: 22:43

To fully answer that question, you need to bring the samples back because it's a pretty big question, and you want to make sure you know the answer to it. So take bringing those samples back and being able to unleash the the whole scientific arsenal that we have on Earth is the only way really to be confirmed. Because as good as Perseverance is, it has a mobile laboratory. It only has, you know, a finite set of equipment that it can use to make those determinations.

Dan: 23:10

And and the master plan here was Perseverance goes, it it captures these samples. It sends kind of early returns back, but like you said, until we get them back on our planet, we won't know for sure what we found. What is the status of those samples?

Swati: 23:27

The samples are on Mars right now. There's two sets of samples. One set is in a location called Three Forks, which is a depot where, basically, the samples have been placed on the surface of Mars and kinda geotagged as to to where they are such that any other spacecraft can go and pick them up because they're just kinda lying on the surface of Mars. The other set of samples is inside the belly of Perseverance and is being held there until it can transfer them to a different mission to come back.

Dan: 24:00

So it feels like we're in this kind of cosmic cliffhanger where there are samples right now on Mars that may or may not shed some light into whether there was life on Mars at some point, but we gotta get them back. And that's that's a a vast engineering challenge of its own, isn't it?

Swati: 24:18

That's an incredibly hard engineering challenge, which is partly why it's taking so long to figure out what the best way is to bring them back.

Dan: 24:28

Swati was working on the mission which is called Mars Sample Return, which is designed to bring those samples back to Earth. But Congress cut its funding in early 2026. The idea of returning samples raises a different question that most people haven't considered. How do you make sure you're not bringing a dangerous organism home? Or conversely, that we're not taking Earth microorganisms to Mars, which might screw up the Mars ecosystem, or make us think we discovered something there when it was really just something we'd accidentally brought with us. There's actually an entire department at NASA devoted to this problem. It's called planetary protection. The thinking goes back to the Apollo missions in the sixties when NASA was concerned enough about a potential moon bug that when the astronauts were returning from the moon, they quarantined them and the samples they brought back just to be careful. The person in charge of all this work has what I think is the greatest title in the world, the planetary protection officer.

Swati: 25:37

Planetary protection work still exists. We have a whole group. They're on every mission, especially the landing missions that actually have contact with the surface of, okay, how do you what do you need to do based on the type of mission? An orbiting mission is a little bit easier because you don't actually contact. It's kind of a remote sensing type of mission, but especially the the landed missions. What's your bug count is kind of what they say. Like, how much are you allowed And they swab all the way up through, like, launch day itself to make sure we're under our bug count. We put in they were the ones who handle the processes and procedures, not just at JPL, but all of our vendors have to follow of, like, when you deliver this thing, what does it need to go through to ensure that it's under its bug count? They have this whole, like, budget of sorts for every element of of that to make sure it's under this? And then how do you implement those processes so that you make sure nothing transfers from one to the other?

Dan: 26:36

This is part of why spacecraft must be built in specially designed clean rooms, controlled environments that filter the air, and minimize the risk of carrying Earth microbes to Mars.

Swati: 26:48

So working in the clean room, "A", it can be very fun, but then it can be very onerous if you're in there for a long time. So because it's a clean room, you have to be in what we colloquial call a bunny suit, which is it's a clean room suit, and it's kinda bunny suit because they're traditionally white, and you're completely covered up. So when you look at yourself other than the ears, you kinda look like a bunny to outside people. And it's a full jumpsuit with booties and gloves and a whole, like, headpiece that just covers your eyes, and then you wear safety goggles over that. So you're kind of entirely covered up. Your shoes, your your hands, your everything is covered up so you're not shedding any skin. And then you go, you gown up in a room, and then you go into a little vestibule area and take a, like, an air shower to make sure that everything on top of the bunny suit is kind of washed out. And then you go into the actual clean room itself. So when you're in the clean room, because you're completely covered up, and you have to, like, wipe down any of the stuff that you take into the clean room, like phones or computers or things like that to make sure that they are also clean. There's no eating, obviously, and there's no drinking. There's no going to the bathroom because you're completely gowned up, and you're in the clean room. So once you're in, you kind of do all your stuff. If you have to do any of the things, water, you know, bathroom, you have to go out. You have to get completely ungowned, and then go out of the vestibule, and then come back and super gown up again in order to go back in. So there's a desire to minimize the gowning up and stuff because it takes time.

Dan: 28:29

Does the engineering mindset creep over into your personal life?

Swati: 28:34

Maybe, in some sense. I mean, I definitely even run my personal life with a lot of spreadsheets and to do lists.

Dan: 28:42

Do you really?

Swati: 28:43

And I I definitely live with the mantra of do what you so that you won't regret life.

Dan: 28:51

What do you mean by that?

Swati: 28:54

The coulda, woulda, shouldas, they don't help prepare you. Right? So when we're building a spacecraft, we create this program of, okay, you test it, you build it, you architect to do the best that you can. And when you launch it, then you can justifiably say, I've done all that I could in a reasonable capacity to give it the best that I've got. So if something fails, like, was either unimagined or so minutely esoteric that you couldn't have predicted it, and you put in all the steps to triage and handle that problem as it comes, and you then just tackle the problem itself. There's no blame game associated with why that problem ended up that way. I kind of do life that way too. Right? Do everything that you possibly can, reasonably, that you want to do and prioritize your life. So do the things that you feel are highest value for you or highest priority for you because then if you can't get to everything, at least you've done the things that matter most to you. And then if problems occur or, you know, life happens, you tackle those problems as you see them in order to get to the other side.

Dan: 30:10

So, Swati, we always end our episodes with a quick lightning round of questions. Here we go. What is the most insulting thing you could say about an aerospace engineer's work?

Swati: 30:21

For the folks that do entry, descent, landing, I've heard one person term us eventually of we're glorified FedEx delivery people because all we have to do is get the package to the ground on Mars, and then everything else blows up. So it's not it's not rocket science, I guess. But in some way, it is just because that particular

Dan: 30:44

It literally is rocket science.

Swati: 30:46

Is so complicated. But we are a glorified delivery service to things that need to get on the surface of Mars.

Dan: 30:51

Shame on them for saying that. In what context do you hear some version of it's not rocket science? People must make that joke to you all the time.

Swati: 30:59

They do. We sometimes use it internally because we use it to distinguish the things that should be easy from the things that we know are are hard to do. So if we're trying to go from one to the other, it's like, this part is not rocket science. Just go do the simplest thing, and don't make it overcomplicated. Use the rocket science for the things that actually are difficult.

Dan: 31:19

I love it. I love it. You guys have your own ironic usage of the phrase. That's brilliant. What phrase or sentence strikes fear in the heart of an aerospace engineer?

Swati: 31:30

I have two phrases for this. One is "break-break", which in the operations context, that's the phrase that you use when you have to interrupt whatever is going on because it's super important and bad. Usually, very bad. So that "break-break", like, you're kind of putting a a hard stop to everything else that's going on in order to to say what you need to say, which usually means something is really bad, is happening, or is going to happen. The other one is "we've fataled". And a fatal message is a type of warning message that we get in the software that we put in that is kind of the, like, the last warning message that you get before you reset the box. Like, if the processor gets to that, like, it can't proceed, and it causes a hard reset of the box. So those fatal messages, they're in lines of like, very deep into the code where you should have never gotten to if you were

Dan: 32:32

Mm.

Swati: 32:32

Doing something correctly. So when you hit these fatal, something has gone very very wrong.

Dan: 32:39

What is a sound specific to your profession that you're likely to hear?

Swati: 32:44

It would be the rocket engines, the sound of rocket engines taking off. Whether we're working on the rockets or that's usually the start of any mission of getting off the Earth, so that sound of, like, that deep engine roar is probably the one that everyone is most likely to hear.

Dan: 33:05

Does that sound, like, spark certain emotions with you? Like, is that a is that an optimistic sound, or are you anxious? Or...

Swati: 33:13

I generally am optimistic. It feels like a beginning. Right? Like, you've gotten to this point, and now you're on your way type of sound.

Dan: 33:24

So twenty years from now, what would you like to be able to say you've done?

Swati: 33:29

I'd like to be able to say that I've made an impact on human understanding. The point of these missions that we do at JPL, the scientific exploration, they're seeking knowledge for knowledge's sake. And every byte of data that we get back from the spacecraft, every sample that we get from Perseverance, they're expanding our understanding of the universe and our place in it and how we can be better stewards of our planet and our place in society and the solar system.

Dan: 34:03

I've been thinking a lot lately about just meaning in work and, you know, what gives people a sense of meaning. And, it it's just kinda right there on the surface with your work, isn't it? I mean, you don't have to look very hard. These are some of the most fundamental questions of the universe. Like, what's out there? Is...

Swati: 34:21

Are we alone?

Dan: 34:22

Are we alone? Exactly.

Swati: 34:24

It's fundamentally trying to answer, are we alone in the universe? How did we get here, and what else is out there? Like, it's kind of so ingrained societally for generations. Right? We've been asking these questions of what is our place in the universe that to be able to actually work on missions that try to answer them, to try to bring another piece of this massive puzzle that is the answer to those questions to move it forward. That's where I'd like to say that I've helped contribute to.

Dan: 35:05

Swati Mohan is an aerospace engineer at the Jet Propulsion Laboratory. What I kept thinking about after this interview was uncertainty and compromise. My previous mental model of rocket science had been, well, it's incredibly complex, but if you're smart enough and experienced enough, you can figure out the answer. But as Swati said, there is no one answer. There are many potential answers and you're continually forced to make choices among them and those choices force compromise because you never have perfect information or unlimited time or infinite resources. You make your best call and move on. And isn't that actually a pretty good metaphor for life? There's no one answer, many potential answers. You're continually forced to make compromises because you don't have all the time or money you'd need for perfection. There's no such thing as perfection. I was so struck by that moment when the rover is approaching Mars and Swati talks about the worry she had that one of those compromises she'd made knowingly might end up holding back the rover as it made its first truly solo journey. It's hard not to see a parenting connection there as our little rovers go out and act autonomously. Did we make the best compromises? And always the worry, what did we miss? Maybe parenting is rocket science. Debating designs when no answer is fully right, showing the perseverance to slog through iteration after iteration, watching your bug count, wearing your bunny suit, and spending years chasing the answers to some of the great questions of the universe. Folks, that's what it's like to be an aerospace engineer. This episode was produced by Matt Purdy. I'm Dan Heath. Thanks for listening.