#701 – Electric Propulsion with Todd Bailey

This is the Empire Podcast. Released August 21st, 2025. Episode 701. Electric Propulsion with Todd Bailey.

Welcome to the Amp Hour. I'm Chris Camel of Contextual Electronics. And I'm Todd Bailey from Starlight Engines, now muon space. Hey, welcome back, Todd. 11 years later, this is a trend that I am... slowly working through old guests and getting updates of where they're from. We just had another 12 years ago guest and now 11 years ago for you. So you've been busy. You've been very busy.

you know i spent like one minute looking back on on what it was that we were talking about then and like you know where i was in life and yeah uh it's a it was a it's a good 10 years or 11 years to have to have uh bookended there's definitely stuff to talk about

Oh, yeah, definitely. And, you know, you and I have spoken on and off throughout that time. I think because you have family in Cleveland. I used to live in Cleveland. So we get to like hang out at Thanksgiving. I think that was like the thing I always remember is like you and I would like go meet up at a bar and hang out for a bit. Yeah, I looked forward to it. It was a fun get out of my hometown and nerd out.

trip that I liked. And then I had to go and move. I moved away. And that was all. I came to New York. You're still in New York. And we got to hang out there. And yeah, it's been good to keep in touch. And really fun to watch your... your progression as an engineer and just like the stuff you're working on last time you were here can you give us a kind of a a quick glimpse into what we were doing last time obviously i'll link in episode uh what was that 194 of the amp hour yeah i think um

That was 2014. Then I think. I think at that point I was still a contract engineer and I think that I still was largely working in my home lab, which frankly I still spend probably 90% of my working hours doing. But I had come out of toy world and I'd moved to New York City to to build new media art for people by and large. So I. um built a bunch of electronics for a show in the whitney um which was really exciting and um i think at that time i was i was building uh

sort of like vanity robots for the rich and famous, which is cool. It's a great gig with a lot of good stories. But, you know, I think like at that point in my life, like, you know, previous to that, I had been like. you know doing art stuff and like you know I spent many years like you know playing in bands and largely working on musical electronics and synthesizers and that sort of thing and and run probably around the time that you and I spoke

was sort of a very intentional transformation from being somebody who was mostly interested in cool. I was going to say you were one of the coolest guests we had had. I mean, like just like.

I knew you were cool because you were this hip... kind of do living in new york working on art stuff but also like you're such a nerd like like like unapologetically interested in jim williams and like all the stuff that i was interested in like like that alone is that is my definition of cool of like yeah maybe you're you know whatever you look like but like

You're actually geeking out on the things you care about. That's the coolest thing you could be. But also, objectively, you were cool in ways that I will never be. I'll use a more derogatory term then. I was more interested in being like a hipster then. In Brooklyn? No. Cool is hard to pin down. I mean, it was like too late. After the fact, it was already not cool.

uh we're both dads now so like it's all over man it's like there's no there's no going back to cool like in that oh yeah you know it's very little yeah yeah um cool is gone uh so So anyway, but I guess like, like with respect to electronics, I had spent a lot of time building things for performance or for

know for sort of like out there stuff the the conclusion that i i came to and it was hard to come to because it required a lot of soul searching is that i i was considerably better at building musical electronics than i was at playing music

Part of you can tell, right? You spend all this time making a thing, and then for me, I would put it on stage, and you're like, oh, it doesn't play itself. You still have to... bring the magic to it no matter how you gotta make robots or something you know like i don't know like synthesizers and need need sequencers right uh they do and and you know i i did right but but um you know at some point i was like you know what if you

What if what you really are better at doing is actually the electronics? bit of it and it required admitting that I wasn't as good at the other things. So there was like some some self-reflection I had to do. So, yeah, yeah, that was probably before I came to New York and New York was like in the process of of like sorting all that stuff out.

i was still mostly working on art stuff but you know other people's art stuff um and uh and like fairly shortly after that i got um i i knew a guy um who also worked on artsy fartsy electronics named andy ritano and andy worked at lockheed martin

And he was like, hey, you should come work at Lockheed. And I was like, mind blown. Like, I don't know. It's not very cool. But I was like, why not? Like, why not do it? Right? Like, if it's true, if what you really are interested in is learning about the world of complicated.

electronics like nobody like working on a sonar system which is which is what i did is like it's if you've ever had to worry about an audio transformer it's like the time where the specs in that transformer really matter and like knowing that stuff it's not like somebody arguing with you about like warmth or something like that it's like no do we get you know the signal to noise ratio is it what it needs to be right um

And it was like, it was stupid not to. And so I did it. It wasn't what I wanted to do forever, but it was a good team and it was not soul crushing. And it was like, you know, weird for all the reasons that you might think it would be weird to go from that world to from like art world to.

defense world one thing i remember is so we spoke about this when you were making this transition i think and i was very curious about it and i remember you talking very excitedly about some of the gray hairs you got to work with yeah and yeah and like That as a guiding, like just for young engineers listening, like that as a guiding light, if that's the only thing that guides you, I think, in a career move.

i think people almost always do well i mean obviously there's personalities and things like that can that can blow up there too right there but yep but just following talent of people to learn from and like having the opportunity like andy like opening that door for you to walk through like that That alone is going to do people a lot of good, I feel like. Whereas I'm not sure it's followed all that. It's not promoted all that much in popular culture.

Yeah, I think I have come up with this sort of rubric for what a good job is at this point now. I've had many more jobs since then. And, you know, a good job to do.

there are three things that i think you can get out of a job and this is all again this is like you know grain of salt this is coming from a place for somebody who's relatively late in career and has a lot of choices and opportunities and if you're just starting out and you need to pay your bills like pay your bills but yeah right uh if you um

You know, eating is important. You know, a job, in my opinion, it can be fun. It can give you enjoyment. It can be lucrative. It can give you money and it can teach you something.

um and for for a job to be worth pursuing i mean again caveat pay your bills but uh you know for this point for a job to be worth pursuing it should be two of those things and ideally it should be three um it's hard to do that but like well there's there's shades of gray for all things like lucrative too right it might be like you know bottom of the paper like bottom 20 25 percent percentile right might not be a lot of money relative but it might be enough you know like that yeah

Right. Yeah. My first like technician job was like, it did not pay very much, but I was like, I was like, I'm rich. So you're right. It's absolutely relative. Okay. So yes. So I would say my whole career has been sort of like at some.

point has been like, where can I go to learn a new thing? The more esoteric you get, like the weirder the stuff you worked on becomes and the more specific it gets, the harder and harder it is to find some sort of figure that knows more about it than you. Yes. And so at some point.

If you can find someone who is smarter and better than you, you should do that. And if you can't, then it sort of becomes the onus is on you to to find a project which will force you to learn new things. Yeah. And I do think there's always the side thing. So like. In the example we're talking about with the Lockheed thing, I'm sure you were working with 30-year experts in sonar. And some of those guys have probably been doing that their whole career and would continue. There's the...

The pigeonholing problem, of course, as well. So if you're trying to sample these different expertises... Expertises? I don't know. You know, you'd have to... You might have to pull the lever and get out before you become the new... 30 year expert unless that's something you find out you really really do want to do and you know keep making sonar only for

30 years, right? Yeah. The thing about that job that was valuable was there were certainly sonar experts, but sonars, you know, there's a lot that goes into it. So there were a lot of people who knew like the system level. trades of how you make a navigation sonar and there were people who knew the algorithms and common filters and uh you know and how the ocean works and that sort of thing but there was finite number of people who were good at electronics and so that's how i got

in there because there's a layer being like all right well we need this signal to get into the you know fpga to run this transform on but man sure is annoying to get that signal in there um so don't you just hate analog you're like nope no i don't actually Yeah. I mean, that's how I got to do that. Like I got hired to be to build some test equipment for them. And it was an equipment rack that tested something. But I spent a lot of time in the.

lab, couldn't keep my big mouth shut, and was like, wow, looks like you're getting some, oh, that's underdamped, or whatever. And if you poke your finger at it. You do it better, son. Yeah, I mean, it really was like that. And, you know, at some point, I think I came back and like, you know, built some prototypes. I absolutely came back and built a prototype circuit here and I dragged it in and they were like.

You're crazy, but yes. Okay. You can work on this thing. What about getting over that hump? You obviously had all this consulting experience. You had the, you know, your portfolio included very technically complex things, but was not a traditional portfolio.

You kind of talked about this, I think, before we started recording. It was like a bona fide. But getting over that hump for Lockheed HR, was that Andy that did that? Again, just thinking about the people that are listening that are not in that space yet, how did you get over that hump? I mean, I will say this. I think that probably every single job I've ever gotten and there may be an exception in here somewhere has come from

knowing another human being, even like at the very beginning. Actually, my first stereo repair job out of college, my first job out of college is repairing stereos. And I got that by answering an ad in the paper. But I think every other job. Yeah.

I've gotten since then has had to do with like just shooting the breeze with people who do similar things to you. Yep. Yeah. So, yeah, it's known as networking, right? It is. It's networking and it's like, you know, I don't know, man, there's a million. things to be good at in life and you know nerds historically like you know are some degree of antisocial um and it really helps to just like you know you don't have to compromise yourself like andy ritano was

buddy because, you know, he was into the Sega Genesis and we both like like 6502 programming. That networking was not like, you know, forced in any way. Right. Exactly. That is like minded and just happened to be. his day job was very beneficial to your career path as well right like but you're still buddies didn't you guys you talked about that last time when you're on here too you guys built your own like a vec9 right that was who you worked on with then yeah

um it was actually uh i think we all everybody worked on that project almost everybody worked on that project worked at lockheed as a day job so um there was another programmer named mike dooley uh who also worked there my friend mike schmidt who i worked on you know

Calvin Klein's robot doors with. We got him a job there, too. And so it's just like, you know, like, you know, all the all the cool kids like showed up and like worked on sonars and then made games about the Soviet Union, which amused us no end. Yes, that is pretty good. Yeah, and there's a little callback nugget in there too. The robot doors that Todd was not allowed to say last time who it was for.

11 years later, you could say it was Calvin Klein. Oh, yeah. Hampton's. Yes, so that's episode 194. People can go and listen to that for all the details on that. Well, not all the details, but a lot of the fun stuff in there. So that was good.

yeah yeah i learned about you know ground loops and formal coding and all kinds of things on that job I was thinking about that as I was spraying down boards one time. I was thinking about Todd having to deal with salt spray from the ocean. I do remember you talking about that. Oh, yeah. Conformal coating is actually still a significant part of my life these days. Yeah, exactly.

we'll get into that for sure yeah yeah yeah on the so the on the lockheed thing you were starting on the test stand then you started moving your way into the space of like more design design of the stuff yep how did how did that i guess first off how did that work with uh clearance like was it like did you have to like go get cleared or did we get cleared before that okay i had to get clearance yeah okay and then like what is that like i guess i mean i don't know what's it like to get cleared

No, no, no. I know that part. I've given people references before. But what is it like then working on something that big and kind of... important uh you know and kind of like a we've only had a limited number of kind of military guests in the past you know what's i suppose so interesting is you know the electrons don't know it's military right they follow all the same rules that they always

follow. You expect all these people to be weird jarheads or something, and they're not. They're all people who are motivated by the same things that you are, largely. The team... especially the the olds who were at lockheed like the people who were 20 years older than me were great like they had been there for a long time they were a different like

generation of engineer who had like a career and stayed at the same place for a long time and like had like loyalty and you know like all the stuff that like young people company loyalty company loyalty yeah um whether it was warranted or not which often it wasn't but you know to my opinion, but like but no, they were like they were they were sincere people who really cared about what they were working on. The probably the biggest sort of like. The biggest transition, I guess, was.

For those of you who've only ever worked in like cool hacker world, there's a lot of in like more legit world. Like requirements driven design is very much a thing. And the first time you encounter it, you're like, this is so stupid. Like, why are we setting out to like have this big, dumb spreadsheet of stuff that mostly doesn't matter?

uh and um getting your head around that at first is annoying um and then at some point if you're me anyway also yeah i'll speak for myself like at some point you're like actually it's kind of the only way to start a design that matters right like what's the point it's like it's another way of being like what are you sitting down to even do guy

When you like, when you sit down and work on this thing, it's done kind of ad hoc a little bit more ad hoc in a consulting context. Right. As well, where it's like, usually if depending on the customer, if the customer has a set of requirements, you're going to do that. But if it's like. calvin klein calls you up and says i want robot doors you have to go and like figure out what the hell does that mean anyways right like you're part of that product side of things versus like delivering

the thing that's on the spec sheet. Yeah, exactly. And I would say, you know, of the things that matter, like going in with an extremely clear set of goals, like I remember there was an older guy, an older engineer named Joe, and Joe was great. And he's someone I still keep in touch with. But I remember building this circuit as... well as I could this, you know, sonar related circuit and like going in and being like, Look how awesome this is. And Joe like took the same data that I had.

and then put it in a graph and then overlaid it with another graph and then was like, actually, here's the error in your circuit and did this really like not very hard to do analysis. And I was like. mind blown. Like, whoa, that's what I should be doing the whole time. Like, like I wasn't rigorous about it. And then I was like, oh, I like I've got to learn how to.

do that. And I guess starting from being like, what's the point of this circuit or this project is valuable in that it keeps you from focusing on stuff that doesn't matter. Right. Like. Yeah. it's easy for engineers to get hung up on things like efficiency and accuracy and often those are great things to focus on but sometimes it doesn't matter uh and spending a bunch of time on a on a on a part of a design

which is not the most important part of the design is detrimental to the project. So you're almost saying in the converse as well, right? So like, so Joe was saying this isn't a spec'd well enough.

and it's measured and you could say this is specifically not spec'd well enough because it doesn't match the graph and here's the error but you're also saying in the other direction you could over engineer it you could overdo it and you might be wasting time wasting energy wasting resources that you We're not actually being asked for and that you should just move on to the next thing.

you know done is better than perfect uh you know which which which you're getting at with that but there's there's also the um if you have extra cycles as an engineer that's great but focus on the thing which is going to help the system like instead of making this thing hyper accurate, maybe make it like have fewer parts or be more maintainable or like, you know, have more test points or like something which which isn't which is also useful, but it's not like.

It's not the like, oh, you know, it was, you know, 12 bit accuracy before and now it has 12 and a half bits like, you know, and the requirement is 10 bits. So that's great. But like, you know, that's not really like you are just kind of screwing around. yeah i have not had a joe in my life in a in a long time yeah but i do have the consulting forum that i run and i find that on there i've had similar kind of like oh like levels of of like

the the need for rigor and especially in a vacuum right like like when when nobody's looking over your shoulder when nobody's asking you to do that chart overlay right like nobody's asking you for that data because there's maybe there's no one above you it's like that's actually when it matters the most i think it's like you're almost like

proving it to yourself and building that habit like you're talking about. I'd be very curious where Joe got that from because that's some hard-won knowledge, I feel like. Joe probably also had a Joe, right? But if you don't have that and that rigor, or that example, positive examples of it, it's...

It's hard to come by, I feel like. Yeah, it's true. And it's cool. It's cool to like watch younger people heading down that same path and to like smack their hand and be like, actually, you can save yourself a couple of weeks if you just look at this other thing now for just a minute. Yeah.

Yeah, yeah, yeah, yeah. I am curious. Later on, we should circle back to when. I'm curious about your mentoring of people now, now that you're on. Well, okay, so now, so you were at Lockheed. Yep.

I remember another bar conversation with you. And... i remember and maybe this is apocryphal and maybe this is not actually what happened but i remember you talking to me about space and you were interested in space and i remember you and i spoke about zephram cochran and i wanted to bring that up specifically here because i always think about that with you especially given what get into Todd works in space now just as a spoiler I suppose but like

But Zephram Cochran is something that came up between us, and I don't remember why, but I think you had said you want to be Zephram Cochran. Oh, yeah. Oh, yeah. Yeah. Not a park rule at all. Accurately remembered, yes, I want to be Zephram Cochran. okay so now we should probably explain who's that from cochran and is he is a actually why don't you explain who he is uh because we both uh sure in the um so

Yeah, I am a big fan of science fiction. I have strong opinions about it. As am I. You know, let's. less this go down, you know, like some forking path. I'm I'm a big fan of Star Trek generally.

um uh because mostly like for a million reasons but ideologically like i am into star trek like star trek claims the future which is like a you know it's not grim um which is cool uh and there's a lot of things i like about star trek in the the world of star trek zefram cochran uh is the engineer who figures out the human engineer who figures out how to make

Warp drive. Right. You know, for humanity, you know, other people in the universe have figured out the warp drive as well. But, you know, he's the one that who like takes. Earth's civilization by dint of engineering and, you know, makes it into something which is, you know, valid across the galaxy. Yep. And he's, Zephyrn Koppikren is also like...

DIY. That's the other thing. Yeah. And the warp signature. So this is in what Star Trek Generations. I think they have him portrayed and then in the earlier one as well. But that's kind of the idea is that he he's the one that kind of drags people.

into the future right right that's the idea yeah and so you're making warp drive of some sort we'll come back to that for sure but i remember you talking about that and then you were you were saying that you're trying to get into space right you were already underwater somewhat space-like uh but then you were trying to get into space so then yeah i i remember that and i i think we had talked about who you could maybe talk to but i then i i think you

You did make a transition over to a space. It was a start. Are you the one that made that introduction? To Sean? To Sean. Yeah, I was. Yeah. Oh, well, thank you. You're the reason this all happened. Well. Barely. Yeah, Sean... Meehan. Sean Meehan. Yeah, of course. Past guest of the show. Sean was at what was... That time was a...

Oh, he was at Planet and then he was going to a startup, I think, or maybe he was already at the startup. Yeah. So when Sean was on the show, he was doing robots after having left Planet or something like that. I'll link in the episode. And yeah, so you talk to Sean and that's...

That's how you got kind of moved over to space. Yeah. So the company was Astra. And at the time they were a they were stealth space startup, which they were for many years. And there was about 30 people. And, you know, look up. Astra, if you are curious. There's a Netflix special about them now. Oh, is it really? How wacky they are. It's called Wild Wild Space. There's also a book about it. I remember there were some other names there, though, too, that have been on the show. So...

Charles, I believe. Charles Aylward. A great friend and a fine, fine engineer. Yeah. Yeah. Yeah. And actually Charles is one of the people on the forum that I was talking about that I think about like the level of rigor and like he's. top of that list you know you and him talking about this sort of stuff is like yeah making sure you're uh you're

Your stuff doesn't blow up. Real important. Real important. And I think maybe Jerry was there for a little bit as well. Ellsworth? Yeah, she was. Yeah, yeah. So lots of familiar names to people on this show. So that's good. Oh, yeah. You know, it was my first...

proper Silicon Valley startup experience. It was my first foray into commercial space. It was it was crazy. That was a crazy job.

um it was it was early in the commercial space kind of stuff too right like planet was like one early one as well but like in terms of like launch company it was what the second one i thought of after after like a spacex kind of thing it was um yeah yeah so forests have fallen about like the history of commercial space and there's a wild wild space is a good one there's another one um

it's based on a book called when the heavens went on sale, which is by this guy who wrote a lot, a lot about Astra and a bunch of other stuff like that. It's got early history kind of stuff, which is cool. But I think a refresher is sort of like, you know, space for a long time was not like commercial space meant.

bigger companies, right? Like Boeing or Maxar or companies that built large satellites um and or large launch vehicles uh design cycles were relatively slow um the number of spacecraft in orbit was relatively low compared to today really you know for better and for worse uh the company that really opened Silicon Valley's eyes to the potential of commercial space was SpaceX. There was a group, I want to say, out of maybe JPL. There was an old Air Force guy who had a bunch of, you know...

youngsters under his wing. And that's what sort of planet came out of. um so i think spacex was first and then sort of the first generation of like commercial space companies included planet and maybe some other companies and i would say astra et al were like the generation following that and as far as launch vehicles go obviously spacex was first and then I would say Rocket Lab was second. And then I, you know, when I started at Astra, I was like,

You know, I'm the good engineers, you know, I think should always be a little bit glass half empty. And I was like, I mean, I can firmly say that, you know, we're in third place, which is not that bad.

um and it's you know but like we can we can do it we can do better yeah uh i have a chart that says we could do better here's our error uh well okay so uh yeah not to get into it but like yeah all right i'll get into it so like the the thing about astro that was a wild experience was it was like the early days at astro were very much like we have these problems we need to solve them very quickly here's a credit card come back when the thing is done wow it was

empowering because you know, it's, it's rocket, right? It's a great environment for learning quickly. It is a good environment for examining what is important and what is not important because like speed is so is such a deciding factor right um it is a good chance to like fail on stage a little bit in a way where like you are you're gonna mess something up

uh you know in a way that like everybody in the company sees it and it costs like a million dollars uh and you like that's you you did that todd bailey todd bailey did that he cost the company a million dollars to you you're saying it's right over there that's him

But you're saying that's a good thing. That's what you said? Is failing on stage a good thing? I'm saying it is an uncomfortable experience. And it is a... So it prepares you maybe for other things that might be big, maybe. If it's a world that you want to be in, it's a useful experience to have because there's kind of no...

you can reduce the chances of that happening by making good decisions you know like slowing down when it's smart to slow down sometimes but it will never there will always be a possibility for it happening and generally the faster you go the more likely it is to happen And all of these companies, at least as of 2025, everyone that I've ever worked for a prize is going quickly.

which means that you will make terrible mistakes and you'll have to recover from it. Got it. Just as a frame for, I guess I'm getting older. I'm thinking more about the people, you know, we have a ton of young listeners. A ton of young listeners have entered Todd's lab as well. Yes, this is my daughter. That also happened in the last 10 years. That's right, exactly. Can you say hi to everybody? Say hello. Are you eating Cheerios? Hi.

Hello. Can he hear me? He can hear you. I can. I can, yes. So will a bunch of people who are listening to this episode. That's right, yeah. Nice to meet you. Nice to meet you, yeah.

kiddo you mind if i it's gone with my long boring daddy story okay all right thank you bye bye yeah i think about that you know that younger crowd and just how it would would this be a thing that you would actually tell people to run towards right is like failing on stage a thing that you would tell them to run towards what in particular commercial no failing on stage like that as a like as a thing to like go after it depends on what you're going for in life

right like you i think probably a couple years ago i would have been like yes you must learn to fail in embarrassing terrible ways and eat your greens and you know like like uh you know uh there are different people who are into different stuff in life I think what you really want is to build hard things. One of the ways to do it is to do it in a commercial sector. If you want to do it in a commercial sector...

then yes, you have to learn that lesson. Well, that's good. Yeah. Then that's a thing people should seek out and maybe go towards. And that's important then. Yeah. Okay. How often did that actually happen though? Like, was it just the fear was there or did you actually cost a million dollars? That was sort of an example I gave. No, I mean, it's things things we built totally did blow up sometimes. Right. And it was expensive and cost a lot of schedule. It was they were unmanned rockets and.

Safety is one of those things that people take pretty seriously at a company like that. So so, you know, largely it was just just scheduling money and not people. Got it. The hardest thing that I probably maybe have ever built, I built.

at astra and it was the the uh motor control electronics for the booster stage engine of that rocket so if you're if you're a rocket nerd you know you'll know that like booster stage engines are typically uh use an oxidizer and a fuel um they're usually liquid and they're they're they're pumped into a thrust chamber where they are combusted uh gas expands and you make thrust in most rocket engines

the the pumping happens using uh turbo machinery which is mechanically spun so so some of that propellant is burned or some of the exhaust is used it spins these pumps the pumps pump fuel and oxidizer into a thrust chamber um astros rocket and rocket labs rocket um at least astros at that time used you know what what they called an electric turbo pump which was an electric motor uh that pumped fuel and oxidizer into the

thrust chamber and so early on my job was building like the power electronics like somebody was like i got hired to be an embedded programmer there actually but then they were like they were like they were like you know what an op amp is and i was like indeed i do know what an op amp is um

Do you know what an op amp is when it's vibrating back and forth very, very quickly? They were like, you're going to be the power systems guy. And I was like, all right. They were like, have you encountered batteries? And I was like, I mean... hundreds and hundreds of times but they were all double a batteries and they were all and there's there's some overlap there you know discharge curve is like still a thing transistors I'm sure was that were involved in some way

So, you know, I built a bunch of battery management system things and then those got done. And then this this pump motor controller came up where, you know, we were. astro is making an a booster stage engine and it was called the delphin engine it was a great engine uh you know i i have many issues with that you know that the you know there there are many complicated things about that company but but that dolphin engine was a good engine and um

so it was my job to build the power electronics which ran the pumps and it was really hard right you had two different fluids one of them was cryogenic so like motor feedback was really hard like if you couldn't put hall effect sensors on them uh you couldn't um you could you could you could use an encoder uh but you had to be really careful about how you did it it had to be really fancy encoder um and you know at the end of it you know we we made a a 40 kilowatt you know 500 volt

30,000 RPM sensorless motor controller, you know, that ran on batteries. And it was really hard. That thing was a challenging circuit. And I think probably the lesson... And this maybe goes back to requirements, which God, if like this ends up all being about requirements, I'm going to feel like the lamest dork. But it's just an offset. It's like the universal balance of like how cool you were in the first time we recorded. And now it's like Todd.

the spreadsheet guy. But the thing about it was right. That was like, we made a great electric turbo pump in my opinion, which was deeply biased, but the, uh, and ultimately it didn't matter right it didn't matter because the reason why it turns out people use mechanical turbo machinery all the time is over some size of pump it's actually more efficient like you don't have to carry

you know, electric turbo machinery, electric turbo pump is physically smaller, but you have to carry all these batteries. And once it's more than a certain number of like watt hours going through those batteries, the batteries weigh more than any pump you're ever going to run off a gas generator. And so. We built this thing. It was fabulous. It got used for a handful of Astros early rockets. And then they're like, we can't use it anymore because we.

Fundamentally, the launch business does not want a rocket that is this size class. And we need to build a bigger rocket. And if we're going to build a bigger rocket, these pumps don't do us any good. And there's some context, I think, in there as well. But Aster was trying to do like smaller payload, smaller.

size rockets i remember they launched out of the desert i think didn't they instead of like early on in the desert early on they tested in the desert they tested a naval air station alameda um okay which was Awesome. It was an indoor test facility like like that was another cool thing that Astro worked out is they they used they got an unused naval base, which had indoor engine test facilities, which is like unheard of. And so they had these amazing test cells.

And so they tested there a lot. And then the early rockets went out of Kodiak, Alaska. So I would go up to Kodiak, Alaska with the rockets. That's cool for some reasons. It was great. I mean, it was a. Fabulous experience. What was the scale of these rockets from start to finish when you were there?

what were the sizes of them they were meant to fit in a shipping container so um they were pretty small by rocket standards uh i can't remember the exact dimensions but like i don't know like a couple meters in diameter maybe and and I don't know, 50 feet tall? Not sure. I think shipping containers are 20, 20, 40 for feet. Okay, that sounds right. Yeah. Incorrect on two out of three counts. It's eight by eight and a half by variable amount, 10, 20, 40.

But I mean, the lesson there was like, it didn't actually matter how good the circuit I built was. Like it didn't, it was like, it was like, I could have, I could have gotten another 10% efficient. I could have made the best one the world has ever seen. And it didn't matter. And it was like. It was a sobering thing to learn, which was like good engineers don't build bad circuits, but all the time they built the wrong circuits. And.

so this is kind of going back to the requirements thing then too because yeah a little bit or it's just being like it's not um sometimes it's not how you build it or how you it's not how you build it it's what you build and so like to make that decision it's like you have to kind of go back up a step from being a circuit designer and think about like what's the problem you're trying to solve in the first place so like system design

versus specifics like system design is a critical piece because there's so many interwoven pieces there too and that almost sounds like a business requirement as well of like just the the scale didn't fit the market. And for me, it sort of comes down to being like, the point of making one of these things is to see it work. If you build a thing, you want to see it fly. And so the goal is to get it to fly.

uh and if you don't yes it system level design matters and yes you know you can't sustain a business that's that you know doesn't have a product that people want um but also your project will never go anywhere like you have to chart a path where where this thing that you brought into the world gets used for the thing that you designed it for and therefore all these other things do have to be right or it's just going to languish on your bench forever

uh and so if you really want your thing that you made to go out into the world you need to see that path for getting it there so like and and with that comes system design and finances and stuff but like like you want to build a warp drive you got to find somebody who's gonna buy that work

drive otherwise you're it's gonna sit on a page forever yeah right and that's like it's you know it's it's all sides of a coin but that's how I think of it if you want to see it go to space you gotta you gotta make a thing that can go to space and that somebody wants to put in space. So this is almost like the...

The ultimate version of good is better than perfect. Perfect would be the best circuit on your bench, but good is the circuit that makes it to space, yeah? It's the one that gets the space that counts, right? So it's the best one that actually goes to space, which is usually...

nothing goes to space. So often it's the only one that goes to space. Got it. Yeah. And then you really find out what's wrong with it when it goes to space, I'm sure. Hopefully. Hopefully you find out most of what's going to go wrong with it before it goes to space.

So before we go into the other, so you kept going with space, right? Astro was a thing. And then you went to other companies and, you know, I'm just pinging down your LinkedIn, of course. But...

One other thing that was very interesting to me was that you were working remote for a lot of this as well I was yeah, so that's also very interesting like how did how did that work because I'm guessing that You know even with the shipping container they probably didn't ship one new york i'm guessing uh no i mean i had the whole thing i had a pump motor controller here um yeah so so yeah so there's there's a

I have many things to say about that, but I'll try and keep it short. I think even probably in the last interview I had with you, the like the home workbench was the thing that I very much believed in. Jim Williams has an essay about it called. called There's No Place Like Home. You should all go read it. I have always believed in having your own sort of work set up. And there's a few reasons for it. One of them is

There are people who are like, I like to get away from work. And I happen to like I've chosen a career where I like I love this stuff. Right. Like like I this is it shows that it shows being able to sit down. on a weekend or whatever, you know, like to walk across the room and work on a thing is valuable to me. It turns out it's also really helpful for your career if that's the thing that you do as a job. So two things about remote. It's not pretty common. It was less common then.

early on i think a lot of those companies thought they were i was going to move so they'd be like all right well we'll start we'll start this way but eventually you'll see how wonderful the san francisco bay area is and certainly you'll come here and that you know that didn't happen uh and there was tension for sure because of that At the time when I started Astra, I did not have a child. My daughter was born while I was at Astra.

And so then it's like a question of like, you know, my partner has a career, which at the time was based in New York City and I had moved to New York City like New York City. I had a great workbench. I had a kid. It required pushing back to be able to.

continue to work in the way that I was. And it usually also requires sort of a willingness when when things are on fire to drop what you're doing and travel. So the having this home lab allows you when your head is down when you're like when your job is really like just being an engineer sitting there and making simulations and tinkering with circuits on the bench being alone in a room is actually fabulous when you build this thing that's part of a bigger system and you can't

test this 40 kilowatt, you know, motor controller. I can do like a good like kilowatt 1200 watts in this tiny room, but like, you know, not 10,000. Yeah. And. you know testing the system like if something was wrong you were like no this is the reason i get away with like you know being able to be a a precious princess about you know

getting what i want is when the thing doesn't work then i show up and you spend like 10 million hours like under the rocket like fixing it and until it works and then and then you leave and so you have to convince you have to give people enough faith that you'll actually do that conversely once you've done that a couple times they're loath to fire

you uh so you can get away with more stuff yeah so it's basically building building trust building relationships that sort of thing yeah totally it isn't i mean it's interesting especially because i i can't think of many more uh you know kind of like physical things than rockets right i mean like rockets are like you know i can ship tiny circuit boards with bluetooth chips on them just about anywhere but yeah rocket parts are bigger and you know but it's all still

gets down to tiny silicon transistors in the end anyways right microcontrollers whatever okay so then you left astra you went to a couple other rocket companies what what uh what did you get to work on there why did you move that sort of thing so after astro was over largely a part of the astro thing was that astro was like hey really really want you to come be here in california and and i you know i wasn't willing to do that and the other thing too was you know that motor controller wasn't

It was it was a whole lot closer to done. It had been through several revs. It was it was like working. And I, you know, I have learned that I. Did you see the new Top Gun movie? Yeah, of course. I really loved that movie. uh but there's a lot of there's a lot of old guy stuff in that movie about you know like uh you know tom cruise is like i'm where i belong and it's silly but it's a little moving and it's one of those things where i'm like

I'm not I know I am not going to be the happy, positive, productive force that I need to be for someone for whom I'm working if I'm not actually working on circuits some of the time. So like, you know, like. it is fine to to be a team lead it is fine to help people to learn but if for me if i'm if i don't have my hands on a circuit board some percentage of the time um i'm not

It's not going to be a thing I want to do. It's going to be a thing that starts to build resentment. And typically with a lot of these jobs, like you sort of have to fight to keep in the trenches. Right. They want to push you up into management, you know, manage all these people, do all this stuff, use your expertise, that sort of thing. Yeah, totally. And you have to be like, no, I am not going to do that. And sometimes that means leaving.

yeah so so i built the motor controller and i um you know i didn't want to move to california and i i had i knew that i liked propulsion at that point i had spent a lot of time thinking about power and it was that was like my you know biggest there was a real like drink from the fire hose like experience and getting into power like i would have said that i was into analog before but like not like rj theta but kind of stuff too much um right

Did you have a favorite transistor after that and you didn't before that? Is that kind of like a power fact? Well, a transistor is so complicated. So it's like, you know, there's like, you know, different strokes for different folks. It really is true. Like, I'm a big fan of GAN.

at this point like i use a lot of gan these days so yes i do have opinions about transistors as well as star trek yeah yeah uh but you know like i like i use a lot of bjts these days like he's a proper bipolar junction and npn transistor which is great uh it's like it's like all those because I get to make this like blob of BJTs now sometimes. But yeah, so I went to a company after that called Rocket Lab, who also makes rockets.

at the time they were they were starting to build they had a third stage of their rocket which they called a kick stage um whose job it was to deliver payloads in a precise um somewhere precise in orbit and they have this concept that they could take this kick stage and they could make it something which would reside in orbit it would be a you know proper like transfer vehicle or something that would that would support a customer payload

um and so that became what is now known as photon i think still known as that which is rocket labs uh um sort of like satellite delivery vehicle um and and you know to get the kick stage uh to turn the kick stage from the kick stage into photon it had to have all these electronics that would allow it to survive and in orbit largely that had to do with uh power again so like it was solar array stuff and so i got hired by rocket lab to do that

but they were like hey if you get that done though uh then you you can i knew at the time like i was i you know i went through the same kind of search when i left astro to be like all right well now you know a little bit more about space you definitely didn't you definitely didn't uh before you didn't know what you didn't know but now looking what's out there if you want to do complicated electronics in space

What is out there and generally it meant like payloads like sensor systems or radios and Talking back to the earth kind of thing. Yeah And I you know, like I love RF as much as the next person, but it's never been my thing uh sensor systems are hard because there's just so few of them like most of the the this the commercial stuff that's up there is either earth observation or it's a radio

uh and so that leaves power which is like a huge problem and if you're into propulsion and you're into power and you're an electronics nerd electric propulsion uh is like naturally that comes across your mind you read about it you're like wait wait wait you shoot a giant ion beam out of the spacecraft

and it pushes you around. That sounds like... You know who else did that? Seth from Cochran. Well, actually... Actually, yeah. I think in Star Trek Parallelance, that's impulse power. Oh, I'm sorry. Sorry. Anyway, I learned about EP and I knew I wanted to get into that. Sorry, EP is electric propulsion. Electric propulsion. Got it.

uh you know rocket lab was like well hey we're gonna need that for our spacecraft and so you can build that after you build these power systems oh the dangling carrot it was the dangling carrot and they were like you'll just you know crank out this satellite power system in like five minutes right did they say did they say but you also have to move out here

in order to do that? Because that's sometimes how they also dangle carrots. Well, you know what happened right around that time was the pandemic. Well, and it was actually really cool because it shut down everybody's electronics lab. except this one. And all of a sudden, like being able to work in this lab started to be a bonus. Otherwise, I suspect probably the same thing would have happened. But at the time I was like, no, I can I can like.

build stuff here and like debug and run my solar simulator and, you know, get you this data. And so it was valuable. And so we got it done. You know, we got the power systems done and they flew. And that was cool. And during that time, again.

uh you know rocket lab did some studies where they were like well you know we have this i think it's it was a hydrogen peroxide motor um that already works for the kick stage uh so you know if you do the trades and like what it takes to get to orbit a or orbit b you know we could develop ep uh but actually it doesn't serve the mission quite as well and it's like going to take many years so why don't we just use the engine that we do have

And it was one of those things where I was, you know, medium mad because. I wanted to be a DP, but it was also a hundred percent the right decision. Yeah, this goes back to the spreadsheet thing, right? This is like that is that's done, done and it works and it. Oh, man. Yeah, that's like, damn it. That's great. That's no, no.

I agree, but I'm going to find a new job. And so I did. And I, I worked for a company after that called Apollo fusion and a woman who, um, was on my team at astra was actually at apollo her name is alex zanos she's a great power electronics engineer uh she's at harvard business school now she also was like i don't know i gotta chart a new path but she um

She should be running something soon, I'm sure. Yeah, if she's not already. So I saw that she was working there and I pinged her about it and she was like, no, man, this place is great. Apollo Fusion started as a fusion company, then, you know, fairly rapidly, they they were like, oh, man, you know, it's challenging. They were like, we're really we may not solve fusion in the next six months.

um and it may be 50 years away now that kind of fusion is it wait so and fusion fusion yeah is that right fusion fusion yep like okay yeah i think it was like a beam on beam fusion concept um to the credit Apollo Fusion is very important to my history as a person. One of the reasons is the guy who is the CEO of Apollo Fusion is this guy, Mike Cassidy. Mike Cassidy has founded.

uh and sold many many companies uh in silicon valley he's a very shrewd ceo um and this is before i joined apollo they you know they were doing fusion and after six months they were like man isn't this kind of hard and you know mike did what

he do. And he was like, all right, if we're not going to solve fusion, we have, you know, this much money left. And this team of dorks, what are we going to make that will make this company profitable? And they were like, oh, we all these people who know how to make ion beams because. you had to make ion beams for fusion what are we what could you do with an ion beam uh and so then they were like oh well you know we could make a hall effect thruster

And so they became an electric propulsion company. In your head, when you read stuff about like Silicon Valley and they start talking about pivoting, do you think about the Friends episode like I do? With like Ross talking, like getting the...

the couch around the corner pivot pivot they never make that connection from my head anytime i hear about pivoting in silicon valley i go straight to friends i don't know i mean there's so much that's so this is like you know there's so much that's so cringy about silicon valley yeah but it's like i could go on for a long time but but in this particular case about well there's a documentary about it it's called silicon valley oh yeah too close it's too close uh so the the uh

Mike was like, all right, we're going to call effect thrusters now. And they did. They built a couple different iterations of thruster. And when I was interviewing, they were like, you know what we should think about doing is get some power electronics for this. um because like again not to be all system z about this but like you know somebody who buys a hall effect thruster is um

is a spacecraft manufacturer. Usually they're like trying to put some antenna or some some telescope in orbit. And that's what they really care about. And they need the in order to close their mission, they need their spacecraft to move around. P.S. Got it. Space in our world, when you say spacecraft, what you pretty much mean is satellite. And they actually do say spacecraft. You know, it's not to make it sound cooler.

Okay. And just as a real quick break, can we talk about, so we've said third stage as well with the kick thing. So just to layer it up. So layer, sorry, stage one is the booster. Is that right? yes can you go one two three and then the spacecraft with the hall effect can you just explain that real quick for listeners oh sure so there's an old saying which is low earth orbit is

50% of the way to anywhere in the solar system. Oh, OK. So so getting off the planet is extremely hard. It's like, you know, that part's tough. But then once you're in space, you have a lot of options for doing whatever it is that you were trying to do in space and go where you need to go. to get off of the planet you need both a lot of thrust because you have to you know lift things out of the gravity well um

It is beneficial to have an efficient engine because you carry less propellant. You should all look up a thing called the rocket equation. I knew that was coming. But it basically just says you have to carry a whole... whole lot of propellant.

And most of your rocket will be propellant. And it's in proportion to the mass of your vehicle. So rockets historically are staged devices. There's a mythical thing called a single staged orbit, which nobody has ever built an SSTO yet. As far as I know, somebody out there will be. Like, no, actually, there's a tiny one that the Jaxa build in the 70s or something. Rockets for delivering payloads to space have some number of booster stages. Well, you know, a bunch of rocket.

You know, a bunch of engines will burn and then typically the bottom part of the rocket comes off and then some more engines will burn and you can have any number of stages. Many. orbital rockets have two stages um you know booster stage and an upper stage uh like the saturn three have three stages

And a stage is just like, you know, rockets fire in that stage. And then that piece of the rocket falls off. The kick stage for Rocket Lab was a very small third stage, which was mostly for maneuvering around in different into different orbits. As I understand it, I could I could.

You know, again, like I could be misrepresenting that somehow. So in that case, the first stage was the booster. The second stage was like the get to orbit. The third stage was like positioning in orbit, that kind of thing. The kick stage. Yeah. Yeah. And so.

a hall effect thruster or an electric propulsion system they all have some things in common um there are many ways to get thrust from electricity and and reaction mass but they all have in common that they're not um combusting something a proper like booster stage engine that uses you know kerosene and

liquid oxygen you know you mix those propellants together uh you set them on fire and then the energy and the chemical bonds is released and that's how you get thrust um ep doesn't burn anything uh it accelerates an ion And so this in theory, you know, if you have a big enough power supply, you can get you just keep turning that juice up and you can get there's no limit. It's not like.

You know, there's a finite amount of energy stored in the chemical bond, but there's no no upper limit in theory to the amount of push you could give to an ion. That is the thing people like to say in. Point of fact. There are a lot of practical upper limits. Well, one is you either have to carry it with you or you have to...

go and capture it from the sun, store it, and then redeliver it, right? That's its own set of problems, I would think, right? Yeah, it goes back to power electronics sorts of problems. Yeah, listening to you, Todd, basically there is no other path for you than this. I mean, like basically... Everything you've said is like, of course Todd's going to be working in this space. How could he not? You're right. I did call out stuff from Cochran long before I started this. So yes, it does make sense.

It's good. It's a hell of an arc, you know? Talk about science. It's not even science fiction. It's just science, man. It's just science nonfiction. Well, you know, that's the thing, too. And, you know, we'll get to, like, the last part of this. Anyway, so, yeah. So, EP is accelerating an ion beam. It's only good in orbit.

um yeah you typically it it doesn't work in atmosphere because it because of the gas densities involved in it so um you know a it won't it won't operate uh and b even if it did operate um atmosphere it produces a very tiny amount of thrust so that's fine when you're in a zero g environment it's it would not be fine if you were on earth in uh moving satellites around as well i think about other ways that i've heard about or maybe wrong but like one is like

letting gas out and just the momentum kind of like gas goes this way you go that way sort of thing but then you run out of gas right it's a cold gas thruster still extremely useful sure sure But like hard to do and like long term energy density type of thing. Exactly. A cold gas thruster is typically used for maneuvering.

You don't usually use them to like change in orbit or do something. It's just like requires a lot of Delta V, which is Delta V is change in velocity. What do you think about the book Delta V? I've never read the book Delta V. What's up with the book Delta V? Oh, man. Oh, wow. Yeah, Daniel Suarez, Delta V. There's two books. There's a third book that's on the way. Okay. Oh, that's got to go on your list. Okay. Recommendation?

You like those? 100% recommendation. Definitely mentioned it on the show before. I love that book. I will check it out. I can't wait to hear your take on it. Awesome. uh delta v though as uh delta v is just like the amount of energy it takes to move to a new orbit right like that's the that's kind of the short it's velocity change uh the amount of energy uh it would be like impulse like newton meters got it got it okay yes so anyway ep

generally speaking, is for use in orbit. But the reason you use it is because although the thrust is quite low, the efficiency is really, really high. So people talk about rocket efficiency and they use a unit called... seconds of isp the number of seconds of isp is a is a comparative measure which says how much mass do you use to go some distance basically um and a really really good

Booster stage rocket engine is around 400 seconds of ISP. And a crappy hall effect thruster is maybe 1500 seconds of ISP. So even like a, you know, even like the best to like a. pretty mediocre one, you know, it's much, much more efficient to use one of these EP systems. And that's because you also have to take that mass to space, right? That's like one of the problems. Yes. So so the reason why it's beneficial to to use less propellant.

uh is yeah you have to carry it there in the first place and once you are there you know if you're three times as efficient you can do three times as much maneuvering um right so you can you can you know if you're maintaining your orbit you can stay in orbit longer it limits your lifetime they're less uh you can maneuver if that's if your spacecraft is into maneuvering which like you know a lot of air force satellites are into that sort of thing

You can maneuver in the parlance, you know, they like to call maneuvering without regret. That's a good that's a good you can you can you can orbit raise. So like a common use for thrusters and is to. is to change orbits so you get dropped off by a rocket in some orbit it's not quite where you want to go uh and so you use your thrusters to get to where you actually want to be right and also i mean don't many orbits not all orbits degrade as well so you have to like kind of like

charge it back up depending on like drag and thrust or drag from the atmosphere and stuff like that if you're in low earth orbit exactly right that's called uh station keeping uh that's a very common use of thrusters again i've learned that one from i think that was The Martian, they talk about it. And I think maybe Delta V, they talk about it too. But yeah, it's asteroid mining. It's all about asteroid mining, Delta V. We've met some asteroid miners in our time. You know, they're trying.

And I hope for the sake of the sci-fi future that I want to live in, you know, somebody works it out. It seems like the only realistic way to, I mean, like, basically it kind of skips a lot of the boost problem, right?

You don't take stuff to space, you get stuff from space and you drag it back. Exactly. So I think when people talk about what is it going to be good for, there's a company called Carmen Plus that is a company that I've chatted with a bunch. And yeah, their tenant was always like, well...

you know you can haul a rock back from space but if you want to bring it back down to earth you have all the same sort of problems um but really when it'll be useful is when people need to build things in space then it's then it'll be super yeah totally yeah it's really interesting really interesting stuff okay so We're talking about satellites with electric propulsion. So that's the main consumer is like someone who's like doing a consumer, like a sensor or a radio thing or a...

Not like a SpaceX, but like someone like that that's got a wants to stay in space. So they do space station keeping. Yeah. So the people who buy Hall Effect thrusters or electric propulsion in general are usually people who make spacecraft. um so so what we would you know in my business uh you would call them a bus integrator or a bus manufacturer and that just means people who make or put together satellites um

And that's who that's who buys. There's there's an old saying about circuit design that's like, you know, the analog part is what, like 20 percent of the circuit and takes 80 percent of the effort. Pareto style. What's that? Like Pareto, like Pareto principle and stuff like that. Yeah, yeah. And there's a similar sort of saying.

well i don't know if there's a saying but there's there's a belief and i you know again grant salt because i'm biased that in spacecraft there is a disproportionate amount of agita that goes into the uh power and propulsion systems um

compared to what the spacecraft's actual job is doing. Like no spacecraft goes up there and is like, we're just going to zip around and do nothing. They're they're always up there to do something. We're going to hang out, you know, not make any money. Yeah, yeah, yeah. Just do that. But the, you know, generating power and getting from place to place is because they're relatively complicated subsystems. They do. They do sort of suck up.

um a high degree of like thought and money and effort on the part of people who are putting satellites up and and the culture is to buy you know quote not off the shelf but like buy Systems that are already proven and then reuse that that's kind of the idea depends on depends on who it is, right? So like some people make their own SpaceX famously makes their own Hall effect thrusters they they build an argon thruster uh and all the star links have one and they they build it most other companies

I think Kuiper, which is Amazon's constellation, is in theory building their own thruster system. Rocket Lab just started, just was like, you know what we really need is a Hall effect thruster. We should call Todd. Yeah. um yeah i tried to get him on the phone and be like hey you want you want to buy one from us and they were like yeah right yeah but um but many companies especially companies um that build like you know fewer than thousands uh of satellites typically

buy really specialized components. So like a lot of people make their own torque rods, which is basically a big electromagnet, which is used for, you know, if you've got a... uh satellite in orbit you can energize magnets in it and use the earth magnetic field to give you different pointing oh cool okay i didn't know that

I knew there was reaction wheels. I remember when Sean was on the show, he talked about reaction wheels a lot, but I don't think torque rods were on the list. Torque rods are so much more benign than a reaction wheel. You can't always use torque rods because you have to be close enough to the earth for them to be useful.

But they're like simple and like nothing to break, you know, by two cents, you can use a torque or if you get away with using a torque rod. Yeah, yeah, sure. They're an example of like a relatively simple space component. So people often. buy those but like um or people often it's it's a good

In the trade space, people are more likely to make that because it's not that hard. But like a propulsion system is esoteric and it's hard to test, you know, ostensibly dangerous. And so like people tend to purchase.

those if if you make less than some number of satellites yeah it kind of sounds like uh i don't know like well i work in cloud space now too but just like people buy you know kind of cloud component like you could engineer everything from the beginning but like if you're not big enough

you don't have the requirements for it like why would you right so they buy off the shelf buy you know small medium businesses do that sort of thing so that makes sense to me i yeah also like they would never get to space if that was the case right i mean like just like just like you know

tiny satellite companies aren't building their own rockets too. They're hitching a ride. You know, it just doesn't make sense. There's still cost basis, but it's not massive. So did Apollo actually get to the point of making this thing? So you, you know, you had this, so yeah. Okay. So Mike, Mike.

Successfully pivoted. Yes. Yeah, Mike Cassidy successfully pivoted. After that, I got hired to help out designing power electronics and, you know, worked with Alex, you know, from Astra, worked with my old buddy. uh mike schmidt back from lockheed and calvin klein doors like uh like you know like you know it sort of like brought everybody along like you know built a you know totally respectable piece of of space power electronics to run this thruster and we flew one and we flew exactly

one and then our company was acquired um and they were they were acquired by dum dum dum astra space um so uh which was you know there were many good things about that uh it was a successful exit to apollo fusion good for a lot of people and uh you know astro took on that

product line and we'll still sell you a thruster to this day i you know had already worked at astra and and uh you know as this this show should be pointing out was mostly interested in building something new so to quote a great great philosopher is going to be a no for me, dog. That sounds like. Well, I mean, you know, when that happens, when your company gets sold.

You're kind of a schmuck if you leave right away. Yeah, there's money on the table for sure. There's money on the table and also like it's bad luck. Oh, I see. Okay. You know, to just be like, thanks for the money. I'm out.

So Mike, being a good boss, did a pretty good job of retaining his team for long enough for me to be like, all right, I'm going to I and my team will get the PPU, the piece of power, the power processing unit, the piece of electronics to a point where it's like reproducible enough that you should be able to.

crank them out. And they're sitting here ready for our first customer. And then I'm going to split. And so that's what I do. Got the job done. That's important. So then you split. So what was after that done? So then that... This takes us to the point where I think I started getting emails from Todd at Starlight Engines, I believe, right? That's correct. Some of my favorite emails. And I really liked that you did that. I don't know when that started, but...

It was it was great. It was a chance to use your sort of your own voice, right? Like I could be as weird as I wanted to be, you know, because it was my sandbox. So at that point, right, like Apollo had sold. I'd worked on electric propulsion. I had done the thing which I had sort of set out to do.

You know, the ACE thruster system, the Apollo Constellation engine was a good thruster. It was a good thruster. It was a great team. It was a good experience. The electronics were good. So, you know, I was like, well, what am I going to do now? And I had only been at Apollo for a short time.

I was at Apollo, I think for a year. And then, you know, after we were acquired, I think I was around for maybe another year after that, but it was pretty short. Now I had worked on electric propulsion, but now I had all these opinions about electric propulsion. And I was like, oh man, wouldn't it be great if, so there were a couple of things that. when i was thinking about what i wanted to do next i was like i do want to i want to build something which is like not the warp drive

But like 25 percent. Not yet. Now we'll get there. Not yet, but 25 percent better than like what's out there now, like like like footnote in the history book. And then in this year, these people made this novel change to electric propulsion and it mattered.

And, you know, five years later, somebody else made something that was better. And then it wasn't Wikipedia footnote at least. Yeah, Wikipedia footnote. Actually, what I really wanted is I wanted to be mentioned in global and Katz fundamentals of electric propulsion, which is the textbook.

about about this that's what i really want uh so if you're out there dan gobel uh you know scarlet engines you know call her at me gobel and cats we'll we'll uh i'll have to take a look at that i've never read a book like that so that's um

It's a good one. You know, like there's esoteric textbooks about almost everything and sometimes they have information and sometimes they're fun to read and very rarely are they both fun to read and have useful information. I still remember my textbook on plasma physics. from my dry edge days and like.

Oh, man, what a great way to fall asleep. Just like the best. Except for the heft of the book as it slams you in the face. Yeah, yeah, yeah. The Dubai length. Yeah, totally. So, yeah, so I had opinions about, like, wouldn't it be great if... you can make a like a marginally better because you know a lot of the time like in commercial space right now there's there's a long history of like stuff that has gone to space but now there's all this like there's more

There are more satellites in space now than there ever have been. And that number is going up all the time. There really is a need for things that there didn't used to be a need for. And one of those is like, you know.

propulsion that doesn't take like several years to build and doesn't cost like a gazillion, zillion dollars. And so I was like, I think that that's what I want to do. And so you look around, you start looking around and there was, there's only one place that I was interested in working. And that was a place in Massachusetts called

Busick. All of you should go buy a Busick t-shirt right now. This company has been around since the 80s. If there's an electric propulsion concept out there, they have tried it at least once. They're like a family-owned company. I don't think they have taken any venture capital.

Uh, they published a million papers and it's like, they've been at it since before it was cool. And they have built, they're a hugely important part of the electric propulsion community. And it's run, it's run by a guy named, uh, Vlad Ruby and and his son Pete now helps him run it and it's like all the sort of things that it's like a real good guy success America doing the right thing capitalism working kind of like

story and so i interviewed there and it was cool and they were just as cool as i i expected them to be and they were really wonderful but i wondered space is slow uh getting things into space is hard it takes a long time the things that i worked on for lockheed i'm not even sure they're on a submarine yet you know like sometimes these worlds yeah these worlds like

like can be slow moving and i i don't know if this is true or not but i really wanted to be able to get something done quickly and i just had this experience at apollo where you know i'd watched this really expert ceo like really pull off a lot of stuff really fast and i was like well what the hell man i'm i'm like not as young as i used to be like if now's the time i'll i'll try starting a company so i one of the other guys from apollo uh mark hopkins

And I co-founded a company called Starlight Engines with the concept of making a new type of Hall Effect thruster system. We started in... June of 2022. We received our first funding in August of 2022 and we developed the first.

commercial metal propellant Hall Effect thruster system. So we use a zinc propellant, which has been done in the lab before. Busick certainly have done it, but no one's built a system which is flight ready. Part of the... the trade and figuring out what to do was being like all right all right all right i am like well versed in like you can make a clever thing and if no one buys it or it's the wrong thing like you're done and we settled on

Zinc and this type of Hall Effect thruster system, not because it was like it was not. It is not the best propellant that you will ever encounter, right? Like Xenon, the, you know, the traditional propellant like Xenon is traditional halifax propellant. It's an amazing propellant. Zinc is not.

quote unquote better in many ways. But you know what zinc is? It's solid. It's solid, which means you can pack it more densely than any dumb gas. It cannot leak and it costs $4 a kilogram. And so it's like Like so it's like all of a sudden your supply chain doesn't involve like stupid like orifices and clean rooms and like valves that are made for 4000 PSI noble gases that take 18 months to get and they're only made like by one company like.

You're arguing with fabs to get it so that they don't use it up and there's only a limited supply. You're never going to win against a fab. There's actual money there, right? Right, right. TSFC is big. So like. so yeah so we were like no man like this is the like honda civic of hall effect thruster systems it has a lot of great it has a lot of great like it's um zinc is relatively light uh which matters for the it's an

It's it's atomic mass is light lighter than Xenon by a lot. And what that means is that favors. efficiency over thrust which most people want more thrust in this world but uh there are some other good things about it too like it's it's a metal so it's easy to ionize the hardest part is obviously

all the other propellants typically are gases. And so you have to make zinc into a gas before you can use it as a propellant. So there's these significant engineering challenges to overcome. But the reason why it's it's beneficial is because it's a system level advantage, right? Like it's. that can't leak that you can leave on a pad forever and nothing bad happens it's an like you know like

like a hydrazine thruster will totally like, you know, mess you up real bad if it has a leak. Like, you know, you can like you shouldn't lick the zinc a lot before you put it in the thruster. But if you did, probably nothing bad would happen. Lickable. Lickable EP. You got it. So there's all these advantages where it's just like, it's easy to use. It's cheap.

It's dense and the performance is better than a lot of the other cheap propellants, right? So like SpaceX pivoted to use Argon Argon is another noble gas. It's a cheap noble gas, but it is like hard to get good performance out of argon it's not as hard to get good performance out of zinc but you have to solve all these engineering problems uh where you have to you know make zinc into a gas which is a pain um but we were like no we can do it and so i know i should

I know I shouldn't do this 85 minutes into the amp hour, but what do the electronics look like for something like this?

Your viewers can't see it, but this is one of the PPUs sitting on my bench right over here. Cool. Like block diagram, I guess, really. I mean, we're not going to get into. Okay. So there's a processor. There's a communication section. Ours talks. RS422, you know, housekeeping supplies and whatnot. There's there's a lot of circuitry associated with that solid metal feed system. And then the main the main thing that.

EP nerds we'll talk about in the electronic design is the discharge converter. And the discharge converter is the power supply that runs the ion beam. And so that's like, that takes up a big part of the board.

Real estate and involves custom magnetics is my first planer transformer that I've that I've ever designed um and that was really fun and great it's throttlable this design so right like if you're into power supply design um you know efficiency is the thing that everybody sort of chases our our system's throttlable from 300 watts to 800 watts really the converter will go down less than that

And the and the, you know, it's a 28 volt spacecraft bus and the discharge converter, you know, can run anywhere from 250 volts on down. So in my head, I'm thinking about like a CRT. Like you're basically thrusting this. It's not electrons, so it's heavier stuff. But it's like there's something that's kicking this stuff out the back. And then you're steering. Do you steer the beam or you just contain the beam?

You just, uh, you contain the beam and that's all done with magnets. So, um, so yeah, also like a, like a little bit like a CRT. Um, yeah. So ions have charged electrons have charge, right? Yeah. So that's how you kind of keep it with, without going off into every direction. It goes within.

the direction you wanted to, which is out the back part, right? Yeah, yeah, yeah. We talk about, people in EP talk about plume divergence. How much of your plume goes in a straight line out of the back? It should be quite a bit if you're doing a good job. Okay. So what actually makes it go in the first place? Like what?

what is pushing the ions out so you have to make ions first and then you push the ions out like what exactly so you um so you start you know in our in our system you have to get from a solid to a gas most systems most hall effect thruster systems you start with a gas um already so uh it's a it's a neutral gas it comes into the thruster thrusters have an anode and a cathode the cathode is a thermionic emitter of some kind, usually just like the cathode.

It's like historically it's just like a tube, right? Like it's a barium oxide. It's barium oxide in a lot of designs and lab six lantern hexaboride in a bunch of other designs. But there's an electron donor, which is the cathode.

And then there's an anode. And then in a holographic thruster, there's a magnet. And so you'll heat up your cathode or you'll make your cathode emit. Typically, it's by heating it up really hot. It will, as they say, quote unquote, boil off electrons and they'll get caught in this.

magnetic field that you've generated in your Hall effect thruster. Then you release a neutral gas. The neutral gas will flow through this area of high electron density. And as it goes through that area of high electron density, there's a.

There is some high likelihood that a neutral gas atom, which is not moving all that fast, will collide with one of the electrons. It will knock an electron off of this neutral gas and it will become positively charged. The location in the thruster where that is most likely to happen is really.

close to a positively charged plate so when that ion goes when that neutral turns into an ion all of a sudden it feels the push from that positive plate and it's ejected out so it's basically like a it's like a tennis ball uh shooter the tennis balls are all kind of bouncing around in the hopper at the same time in order to get ready to shoot out the back or something. Yeah. He's like, no, that's not how electronic, that's not how it works, Chris.

Todd, can I work an EP now? Can I? It's not like I am a communicator Todd It's like if you have a cloud of tennis balls, okay, and you know and you're sitting like near them with a magic wand and you point at one of them and then like that one goes really fast that one goes okay yeah so probably tennis balls was a bad starting point huh so and so the novel part is first that you're starting from solid and making the gas right

and then but then is everything else kind of the same then like they're just feeding gas in but you're making gas and feeding it in um that's the hardest part of it yeah the hardest part of is is the novel propellant and that's the sort of the biggest differentiator now i think we happen to do a lot of other things really cleverly like um you know like uh the sort of like

um electrical isolation in the thruster head is like good for us like this uh you know we survived really high shock and vibe levels which was hard to do and that took a lot of engineering work the throttle bowl design like i'm particularly proud of like most of the time a lot of these thrusters will be awful 100 watt thruster and what it what it means is that you know

you can only sell it to a bus that has 400 watts. But some people will be like, I got 300 or 350 or man, I want twice as much thrust. Is there anything you can do? So you can you can use it on more missions if you can make it throttle. So designing the power supply to do that was like I was, you know. I was proud of that. Some of the heater design is novel. So there's some incremental improvements, but the one that matters the most is the propellant.

Does Starlight care about the collection and storage of power in the first place? Or is that up to the people that you're selling to? Like collecting from solar, storing in batteries or some other mechanism, and then delivering that power to the EP?

We don't build anything to do that. I mean, certainly because of my background and certainly because we are often one of the largest consumers of power in a spacecraft, it benefits us to be savvy and think about that sort of thing. But we don't like to sell batteries or anything.

got it we thought about it uh there's not a great business case for selling space batteries sure okay but i'm eager to be proven wrong on that okay cool cool i mean are there other sources as well so like solar feels like not easy but easier than like a like a rt rtg and what's the rtg like the rtgs i i read about like are going away because it's like the this the plutonium they need for is is is is harder to get because of nuclear arms treaties but like rtgs can also generate power right

and then deliver it but like is there a benefit do people choose between them or no um for commercial missions solar is kind of the only game in town um okay so getting an rtg into orbit requires like the president to sign something like it's like uh it's uh flying uh nuclear anything is tough now there's a big movement in space right now to fly nuclear reactors

And if you're a propulsion nerd, you're probably into that because it opens up all this kind of propulsion, which was not feasible before you before that reactor is up there. But for commercial missions, not always solar.

got it yeah i mean i think about it just like if you wanted to go somewhere very very far away you know you could have a little bit of acceleration for a very long time but you can't do that if you're farther and farther away from a star so right yeah nuclear would be important i feel like not that these that's what people are doing here either but you know someday when the fusion reactor comes up todd you're gonna have to do this so

I would love to be at a point in my Silicon Valley career where I can be like, I too will try and save the world because I've done everything else yet. To make the world a better place. To make the world a better place.

yeah i don't know i mean if you're gonna like if you're gonna get competitive with your you know rich buddies about something like saving the world's like you could shoot worse yeah well yeah uh okay so it works i mean like that is the that's the punchline here you got the what was the

getting over that hump was the was it was that solid fuel to making it gas and then using it like or was it just kind of getting everything together and making it work at all um early on before we even got funding we like ran some tests to make sure that we weren't diluting ourselves. And so, you know, pretty early on, we became, as far as I know, the first thruster system that ran every bit of it on a solid metal.

And so that worked. But no, making a thing flight worthy is really hard. That's probably the most challenging thing, right? Like building a thing that will like... survive shock and vibe that you can like stick a screwdriver in the output of any of the various like and that's like a thing i have a screwdriver that's sitting over there it is the is the like final acceptance test screwdriver of being like when you build a power supply you jam the screwdriver in the output and you put it on the

up a bunch of times and you watch recovery looks like and then you should expect it to pass all of its tests again after you've done wow wow um you know designing it not just for space but for for the fact that like it's gonna live a life before it goes to space and like you know to survive and and make it through all that is the hardest part and and for us yeah the the the novel propellant system is both like uh like i've built

electronics before mark has built thrusters before but nobody's built the feed system and the vaporization system um like the like the one we've built and so that's the one that's full of like surprises where you'll be like oh i we didn't know that before because i don't know if anyone knew that before and that's and it's it's what makes it fun too yeah yeah i mean i mean i can imagine there's a an additional you know despite raising funding

It's not like startups have access to all the things that SpaceX have access to and all that sort of thing. That scrappy factor is also, I'm sure, a huge piece of getting this thing off the ground. Oh, yeah, yeah, yeah, yeah, yeah. I mean, our first thruster was our first cathode.

looked like a Home Depot plumbing pipe because it was a Home Depot plumbing pipe. You know, there's a hollow cathode inside of it, but the but the the you know, the structure of it was like a gross iron tube. Nice. Nice. And.

Yeah, like we built a we built a vacuum chamber that would get down to Mark really built a vacuum chamber that would get down to ten to the minus five tour for like fifteen thousand dollars, which is like which is unheard of. Right. And it's because he carved it from a tree and because he's done it a million times, you know. so it's certainly scrappy and that part's fun too right like if you're like sure yeah yeah that was my favorite parts of the the newsletter you sent out I mean

I don't know how I got on the mailing list, but I was sure glad I did. And then eventually seeing the purple flame that you shared as well, it was super cool. It's Plim. Not a flame. Oh, boy. Okay. Haven't you been listening? There's no combustion. It's not a flame. Got it. Got it. Well, joke's on you. I don't know how flames work either. I don't know how they work either, but I'm pretty sure it's not. What do I look like? A chemist? A caveman? Yeah. Oh, wow. That's really cool.

so you guys built your own chambers you tested it that sort of thing yep i mean throughout this whole process todd i believe i asked you probably 85 times to come on the show and you're like, I can't yet. I can't yet. I can't yet. And then finally you sold the company and you're like, yeah, now I get to, which is great. And now I get to. Yeah. I was very excited about that. But like the.

Where is it in the going to space? Is it up there yet? No, it is not up there yet. That's its own thing, right? Like you said, we've already set up the stage for that. It's not like it's an easy thing, flying in space. No, it's not. Part of the job is when you make a novel thing like this is to try and get someone to believe that you're not a quack.

And it helped that we built this other thruster system before that totally did work. Then it's to get somebody to hopefully buy one of these things before anyone else has flown it. Which, you know, our policy was always just give the first one away. Like, yeah, where you're like, you know, just get it up there and functional like the like the like amount of credibility you get from having a system operational in space is so great that that it's worth.

you know whatever money you you lost uh to to make one so so we sold we've sold a total of four of them um for you know whatever reasons they're like we've sold four we've delivered Two kits. And neither one of those... I don't think either one of those has been to space. We actually wouldn't necessarily know if they had been. That's its own thing. Yeah, that's a different role. Yeah, it's its own thing. That's like a...

Digi-Key doesn't get to know where the parts go, right? Exactly. They know the shipping address. They don't know the end result of if it's in the remote they're holding in their hand at the end of the day, right? Totally. So, I mean, what we can say is that we delivered them to customers. Yeah, right. You know, after these four...

know we had a company come around and and it's cool it's it's it's really a small world in some ways like we knew some of the founders from this company and had like met them a handful of times before and had been like badgering them to buy engines from us and they were like yeah yeah yeah yeah yeah and then you know

this company they're called muon space they're they're good engineers and savvy people and decent human beings um but you know they had their own stuff going on and they weren't interested in our thrusters early on and then something happened which you know read they had thruster problems uh and uh and then they got really interested and then you know we started talking and they it was cool because they were

They were not put off by the fact that we were two guys in a garage and a handful of contractors. They were into it. And they were like, we had the exchange that was like, well, you could buy these thruster systems or you could buy the company. And they chose to do that. And that process, let me tell you, like.

She had another hour and a half. Let me tell you about going through that. Like, that's like a gray hair inducing process. The roller coaster ride. So I hear. Yeah. And it really is crazy. Like, you know, being.

so i was officially the ceo of starlight engines now starlight was not a big company um and it was a deeply technical company with people who i'd worked with previously so you'd think how different is that from being you know from like being a tech lead at a you know another company uh and the answer is it is so different it is so different uh um

How many lawyers have you talked to in the past couple of years, Todd? We had, I mean, a lot. But Starling had a great lawyer. I came out of this process with such... like superhero like admiration for our legal counsel. um her name's rachel paris from dla piper uh you know anyone who needs a a fabulous extremely expensive lawyer um or you know corporate m a you know you could do a lot worse she was amazing yeah

Yeah, but the process is crazy, and it's not like engineering. There's no straight lines, A to B, put in more work, get more, get more. Well, I guess they put in more work, but yeah. There's a lot of emotional rollercoaster, I'm sure. Yeah. Yeah. Well, at the end of it, you did sell. And that's great. Congrats. But the job ain't over. So now you're... No. What are you going to be doing in Mewon? Or what does Mewon build, I guess? Mewon builds satellites. Okay.

So, and, and, uh, you know, I'm, I'm probably misrepresenting them in some way. They would, they would use their marketing team would use, you know, more complicated terminology than others. They sell a little serious systems, but mostly I think the parts that people really want, right. Is the part that goes up to space and.

uh you know does stuff muon is probably the most famous right now for um building fire detection satellites so they they built a um a payload which is which is good at scanning different types of infrared and and collating that data in such a way where it's it's it's quite good at figuring out where fires are in the world and which was both.

relevant and like super useful, primarily sensing payloads. So they're like, they're kind of the good guys. They have good leadership. You know, it was like, it was, they really need thrusters. And it was like, it was a, it was a. That process, I think, can go really south and time will tell how, you know, how the long term relationship goes. But so far, I'm pretty optimistic. Well, I'm really excited to see what you I mean.

Last time I had a 12-year-old guest on a similar kind of journey of like, wow, I can't believe you got to where you are now. And I'll say the same thing, like another, let's not make it 11 years, but wow, 11 years from now, who knows what you're going to be building, Todd.

have to assume fusion engine you know fusion warp drives rather sorry warp drives yeah i wouldn't have known then and so yeah i think it's fair to say i don't know now where uh can people find you muon you know your starlight stuff is that stuff online somewhere people can look it up Our old website is very vaporwave and has some cool pictures, but not a lot of useful information. Vaporwave has not persisted, but I enjoy it. I enjoy it.

It hasn't. But if you want a blast from five years ago, StarlightEngines.com is like a picture of some of our stuff. Muonspace.com is where you can find muons. business. They're in Mountain View, California. They're a great company. If you're trying to get into space, you could work at way worse places than you are. For me, I'm actually not really on social media much anymore. but uh i am on you know i am on linkedin um business yes um yeah i don't know if you want to if you ever want to

Anyone who ever wants to talk electronics, that's usually what sort of like electronics. Yeah. Yeah. Great. Great. Great. Great. Yeah. I'm sure, you know, as you build more EP, you'll need more. plucky young engineers that you can mentor as well. So that'll be great. Hopefully some of them listen to this and...

come work for you and build the fusion engine of the future. For sure. Sorry, I keep saying it's fusion engine. It's warp drive for the future. All right. Well, thanks, Todd. Thanks for being back, and we'll chat soon. Thanks, Chris.