蒂姆·多德：SpaceX、星艦、火箭發動機與太空旅行的未來

Lex Fridman Podcast #356 – Tim Dodd: SpaceX, Starship, Rocket Engines, and Future of Space Travel Machine transcription by Qwen3-ASR 0.6B (MLX, local, Apache-2.0). May contain recognition errors. The following is a conversation with Tim Dodd, host of the Everyday Astronaut YouTube channel, where he educates and inspires all of us with detailed but accessible explanations of rocket engines and all things space travel. And now a quick few second mention of each sponsor. Check them out in the description. It's the best way to support this podcast. We got BetterHelp for mental health, MasterClass for online learning, Shopify for e commerce, and ExpressVPN for privacy and security. Choose wisely, my friends. Also, if you want to work with our team, we're always hiring. Go to lexfreeman dot com slash hiring. And now onto the full ad reads. As always, no ads in the middle. I try to make these interesting, but if you skip them, please still check out our sponsors. 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There is a big sexy button you press it it just works on any operating system on any device. That's the thing you want from software is it just works? It does this thing. It doesn't do a million extra features. It does this thing. It does it for an affordable price. Anywhere you want to use it, it works. And obviously for VPN, what's also important—the bandwidth is super fast. It's fast. It just works. I don't know. I love great design and engineering in the software space, so that's one of the many reasons I love ExpressVPN. Go to expressvpn dot com slash lex pod for an extra three months free. This is a lexfreeman podcast to support it. Please check out our sponsors in the description. And now, dear friends, here is Tim Dodd. Can you give a brief history of SpaceX rockets? So we got Falcon One, Falcon Nine. There is different versions of those Falcon Heavy, Starship, and also the the Dragon capsules and so on. Well, yeah, Falcon One is where it all started. The original intent and the original idea of SpaceX was Elon wanted to try to get something to Mars. You know, he saw that NASA didn't have a current Mars plan, and he wanted to go to Mars. So he decided, "How do I best do this?" He literally wanted to at first purchase a rocket from from Russia. Then on the after a foiled attempt at doing that, he decided he was going to try to develop his own rocket. And the Falcon One is what came out of that process. And he developed a pretty incredible team. Like I don't know how exactly he stumbled upon the team that he stumbled upon that quickly, but the people that he assembled were amazing and they built the Falcon One, which was a single Merlin engine followed by an upper stage engine called the Kestrel engine. Pretty small compared to the things they're working on today, but that Merlin engine continued to evolve into being the power plant for the Falcon Nine. They went from a small lift launch vehicle up into the medium class launch vehicle, so they could provide services for NASA. That's one of the big things they first kind of hung their hat up was they got the opportunity to fly cargo to the International Space Station under originally was called the COTS program, the Commercial Orbital Transportation Services. For NASA, which evolved into the Commercial Resupply Contracts, and that's when SpaceX developed both their Dragon capsule, which is a uncrewed at first spacecraft that can dock to the ISS, and the Falcon Nine rocket that can take it to the International Space Station. The Dragon rides on it's the thing up top that rides on the big booster thing that that launches it into orbit. Exactly, yep. The Falcon Nine's the the semi truck, the Dragon capsule is the payload. You know it's the thing being dropped off basically at a destination, and in this case, the destination is the International Space Station. And yes, so they developed those relatively quickly and became a commercial success before you know it. They're now the number one launch provider in the world, launching more mass to to orbit than anybody else, launching more frequently than. Countries like the entire country of China who's going crazy right now with launches. Granted, China beat them by two launches this last in twenty twenty two, but prior prior year SpaceX beat the entire country of China. I mean, it's it's nuts. And just like you said, SpaceX still beats China even this year in terms of the amount of payload. Those so the mass to orbit, yeah, the mass to orbit right that China had like sixty something, a couple more launches, but the there was just like small cubesat type of launches. Exactly, some of them were literally like one hundred kilograms or something, you know, like not not large payloads. And so SpaceX customers are different and different. So whoever wants to send payloads up into space, yes, but right now their biggest customer is actually themselves with Starlink. With Starlink, one of the biggest reasons they've launched so much mass to orbit is because Starlink has designed around the payload fairing and the payload capabilities of the Falcon Nine rocket. So you know because they're vertically integrated because they build their own satellites because they're building their own rocket, they can literally design a system that's you know another manufacturer might have made a more square satellite that was heavier or something, but SpaceX looked at it from a blank slate and said, "Here is our constraints, our payload mass constraints, our volume constraints, and they made a funky looking satellite. " Things like the size of a you know like a table folded up, which isn't anything I've you know really ever seen before. So but it's purpose built to fit as efficiently as possible inside their fairing and inside the capabilities of that rocket. So therefore, because they're launching those like an insane amount you know dozens you know forty fifty times a year or whatever. They're they're just putting up insane amounts of mass like we've never seen before. What about the different versions of Falcon Nine? So we can linger on that. What are some interesting memories to you of the different developments in Falcon Nine? The very first Falcon Nine had a square array of engines. It had like a three by three by three grid of their Merlin one engines—the one Ds. And I think it only lasted—I don't remember—it was two or four flights before they went into this octa web configuration where there is eight like a ring of eight engines with a center engine in the middle. Still in the same diameter that the rocket was, the fuselage was more or less the same three point seven meter wide diameter, but the the actual thrust structure changed. And one of the big efficiency gains was you no longer have you know a corner engine and then like a edge engine and then another corner engine. You can just make eight of the same you know kind of part of the octa web it's called you know the same shape and then your interchangeability and your manufacturability becomes a lot simpler. So that was kind of one of the bigger upgrades at first, and they kept stretching it. Every time they like touch this thing, it got longer and like are taller and taller technically. And then the next big feature that you saw in twenty fourteen would have been they added landing legs to a Falcon Nine rocket, which was I was at that was the first launch I ever went to, was actually to see. It was CRS three, so Commercial Resupply Mission three, and it was probably their god I don't remember what that was like their fourteenth or fifteenth launch or something like pretty early on. And people were literally laughing at the idea of them putting landing legs on it. They just thought it was stupid. They're like, "Why are they wasting? Why is this billionaire Elon Musk guy wasting his time trying to land a rocket? It's not going to work." So you said the Mars plan was there in the beginning. What about the reusability of rockets? Was that there in the beginning? I think reusability definitely you know it's it's a necessary part of making any kind of interplanetary mission you know in order to actually do that just financially you have to start reusing these things. In terms of the development of the Falcon One and Falcon Nine, how early on did the goal of reusing the rocket having the rocket actually land? How early did that goal creep in? I can't speak for Elon and SpaceX, but it was pretty you know immediately they wanted to try to recover and as a matter of fact I think the very first two Falcon Nine rockets and Falcon One I think they even wanted to try to recover using parachutes to recover the first stage. And now fast forward you know almost twenty years later and Rocket Lab is actually doing a concept like that where they're pulling a parachute after the first stage is reentering and they actually are trying to recover it with a helicopter. He's going to try to snatch it out of the air. They've actually done it. They've actually done it successfully once. How does the helicopter grab the the rocket with this giant like drag line and a hook? Oh, and then literally just like grabs, snags onto the parachute. Wow, it's pretty amazing. And but this is a small rocket. Their rocket's only about a metric ton. The the booster is empty, so the rocket releases parachutes. Yep, like really high up. I'd love to see this. Yeah, it's an interesting idea. There is so many interesting ideas and possibilities like SpaceX basically just innovated. A lot of different weird ideas, just in in the pursuit of making things more efficient, reusable—all of that. So basically thinking from first principles how to solve this problem, and so what you find is like you'll get all these kind of crazy kind of solutions. And with SpaceX, they weren't even getting to the point of the booster surviving reentry long enough to be able to pull the parachutes. Yeah, you know their mass fractions, you know and and that varies. Every single rocket's different, you know. All the you know for instance, Rocket Lab uses carbon composite fuselage and tanks, or you know same thing and that's very very lightweight has really good mass fractions and therefore their drag coefficients and things like that. They were able to survive reentry of the first stage, which is something that SpaceX wasn't able to do at the time. What's what the kind of the big I think breakthrough for SpaceX with reusing the booster? Is they they realized we have to basically slow down before we hit the atmosphere. So they actually do what they used to call a reentry burn, which I still think is the correct term because it is reentering the atmosphere. But now they call it the entry burn and they light up three of the nine Merlin engines not only to slow it down but actually even while those engines are firing it creates like a a literal like force field as it's falling through the through the atmosphere. Interesting and but it also decreases the velocity by almost half or around half and then that therefore decreases the amount of you know the biggest thing with the atmosphere is that as it gets compressed against the the front of any anything flying through the atmosphere, the compressed atoms just get hot and they can get so hot they turn into a plasma and they get so hot they can just absolutely destroy anything. So they slow down enough that the air molecules don't end up you know destroying the vehicle on reentry. And then they then they realized I think at some point it's probably a similar crossover. They're like, "Well, if we're lighting the engines already to slow down in the atmosphere, we can just use that same engine to land." And so like, well, what if we just stuck landing legs on it and just landed the thing vertically? And next thing you know is December twenty first, twenty fifteen they did exactly that for the first time. The first time, so you were there before that then, right? Yeah, yeah, in twenty fourteen, yep, early twenty fourteen. So that and for me like that was so fun watching. You know that was like the peak of me just becoming obsessed with with this idea. I am watching with like and back in the day it was like months between launches, you know. So a launch was like a big idea. I'd wake up at three AM to watch this landing attempt or whatever you know. And every you know there was CRS four almost almost landed, CRS five almost landed, CRS six, CRS seven blew up. I was watching that on I think it was like a Saturday morning or maybe a Sunday morning and I remember watching that and watch it blow up and I was like, oh my god, now what you know and. It blew up on ascent. It was their first failure, so it was their eighteenth flight, I believe. CRS seven, the upper stage had a one of the t here is bottles inside the tanks that are filled with helium and one of those bottles broke off on ascent and actually just completely over pressured the upper stage and the upper stage blew up and the whole rocket went kaboom. In an uncontrolled manner, and so so then they came back with vengeance. When they came back, the first mission back is the first time that they landed a rocket, which was awesome. So the return to flight after the anomaly was was yeah was was landing a rocket and stuck the landing. Yep, well actually the first time. So the first time you were there, what was that like? What do you remember from that from that day? Just I was surprised at how much bigger the rocket was than I imagined. I was I originally when I was going down to Kennedy Space Center, I was disappointed that I wasn't seeing like a you know I didn't know a ton about rockets. I knew enough to like know what a space shuttle was, what like the Saturn Five was, you know, but that was probably about the end of my knowledge. I just remember being disappointed that I wasn't seeing a big quote unquote NASA rocket flying. You know, I was thinking in my head like, oh, I am going to see this launch. It's probably going to be like you know three stories tall or something. You know, just some little skinny little stick and some little firecracker and yay, you know. And I think I'd almost been pitched that too. I think the the people that I was working for at the time, I think they kind of were downplaying it. It's like, well, it's not a big rocket here. It's not going to be that exciting, you know. But we get out there to the pad and I am like, this thing's huge. This is not a small rocket. Like this is, it's you know it's seventy meters tall, two hundred and twenty feet tall. It's huge. And I think people forget like the scale of that. You know it might look skinny and tall and all this stuff, but it's still a very very large piece of machinery. It's physically about as large as you can ship. The booster is about as big as you can ship across the country. Period, without like completely shutting down highways. You know it is made within those exact specifications of of like having you know lane privileges and bridges and everything. It's you know twelve feet wide, three point seven meters wide, and it's forty five meters long. So it's like exactly what you can fit with a pretty standard. You know like before you start getting into crazy amounts of of problems shipping the rocket and it's huge. It's huge and people just don't understand that. And so when I saw with my own eyes, I remember just being like, this is so much cooler than I thought. It's hard to believe that that thing is going to have to lift off the ground and launch up into the air. Maybe that's the most humbling aspect of it that something that size humans have come up with a way to take something that size and launch it up into the air. Yeah, there is certainly a very humbling aspect when you watch it actually leave. Was was there a sound to it? Was there like a feeling? What were the different experiences you first remember? Well, ironically, I didn't end up getting to see that one fly. Oh, I went home. My camera saw it. I left my camera out there like a remote triggered camera. My first images as a launch photographer at the time was was CRS three, but I went home. It scrubbed too many times. This is back in the day they were scrubbing like often and they'd be like a three day, five day, seven day. You just never knew. So I go home and I watch the live stream of it. So I didn't even get to experience my first launch. And any anyone that's ever tried to you know go to a launch is can probably empathize because yeah, scrubs are very common in the spaceflight world. So that one I didn't get to see, but since then obviously I've been able to attend very many launches. How much do you understand the control involved in the landing? How difficult is that problem? I couldn't tell you a single thing about like the code and like the avionics behind it, but I can tell you all the hardware that makes it happen. If that helps. Well, that I mean to me, it seems like whenever I talk to people, they they say it's not that big of a deal in terms of the the level of intelligence in the control, but to me it's just like when you observe it. It seems incredible because all the variables involved, all the uncertainties involved, all the. Um, because there is aerodynamics, I mean, like there is different temperatures, there's so so much going on with the fuel, the burning, the the combustion, just everything that's going on to be able to do perform control at such high stakes effectively. Like you know, I that code is probably not written in JavaScript, I guess is what I'm saying. Actually, no, I don't. It if I remember, I again this is well outside of my domain. Um, but um, they they code in a common language. It's is it's probably going to be C. Yeah, I'm pretty sure it is, and that was one of the things that was weird is that Elon when he you know started SpaceX was like, we're just going to code in the most common language so that we don't have to like have people learn this archaic you know weird thing and we can just literally pull people off the streets and be like, you write it you know and. Yeah, it's probably C plus plus. I mean, it'd be epic if it was like Python or something, but I don't. I think like reliable systems have to be written in C C plus plus probably, which is a common language, which is something. I imagine like NASA engineers would probably have to use some kind of proprietary language in in the olden days for for security for privacy all that kind of stuff. Well, in the old old old days, like they were inventing code and language from scratch. For sure, but still it's just still incredible that it's able to do that. Like just the feat of engineering involved is just it's truly. It's like one of the marvels to observe about these rockets coming back to Earth that they're able to land. Like the drama of it is just incredible to see. Yeah, well, the one of the fun things to remember too with specifically with the Falcon Nine and the Falcon Nine or Falcon Heavy boosters. I mean, it's the same thing basically. Um, they shut down all but one of the nine engines, and even with that one engine at its minimum throttle setting, it's still too much thrust to hover. So as this rocket's coming down, if they start a little bit too early, if they light that engine too early, it will actually stop above the ground and will not be able to lower itself. It will literally stop like say stay say it stop 200 feet above the ground. Their only option is to kill the engine and then it's just going to fall those 200 feet. So they it's what we call like a suicide burn or a hover slam kind of interchangeable terms because your thrust to weight ratio is never below one. So they have to actually literally be riding the throttle. So what you do is you kind of start ideally you know you kind of start like in the middle of your window of of throttle range. So let's pretend your engine can throttle down to 40 percent of its maximum rated thrust. You might start at like 70 percent of thrust in the middle of that like window of where it could burn. So that so if all of a sudden it's kind of coming in too hot, you have room to throttle up. If you're coming in too, you actually you know a little too early, you throttle it down, you have a little bit of wiggle room. It's just amazing how smoothly and how perfectly they're able to still control that thing even though they're down to one engine out of the nine and they're still riding like the finest margin of what's possible and they're they're continually playing with that to try to get it because every every bit of fuel they're using and propellant they're using to land is propellant they weren't using to put something into space. Yeah, so they want that to be as efficient as possible. They're really like watching them hone that in and and just continue to evolve and edit that and and just get it to be the workhorse. We're coming up on a hundred consecutive landings, perfect landings. A hundred, I think they've done like 150 something landings altogether, 160 altogether. But we're talking like in a row without blowing up, which at you know five years ago was completely experimental and insane. And now we're coming up to the point where we're 100 in a row. It's like this is becoming more reliable in the landing, which is not the primary mission. This is purely for SpaceX's like gain is to recover the booster. It has nothing to do with the effect of getting the payload on orbit, you know, most of the time. And the landing is really only for their their benefit and their gain. Long term gain, like it's a long term investment in in being able to recover the the boosters. Can you believe all this was done basically 10 years? So we've seen this development over a period of 10 years. So like we started commercial space flight at scale to today, where it's almost almost starting to be mundane. Yeah, Falcon Nine is able to do. Yeah, I can't really believe it. I mean, obviously, even just in the I I think I'm a fairly fair weather fan really didn't start paying attention to like 2014. Yeah, and just seeing what it was like back then to what it's like like I don't watch every launch at all anymore like I'll catch the big ones, I'll stream some of the really big ones but like back in the day I like I said would wake up in the middle of the night to catch these streams or you know catch these launches and watch them because they were such a big deal and there's maybe only five of them a year you know and so it's a really big deal nowadays it's like oh yeah there's literally like two a week on average now it's insane from SpaceX alone. Let alone you know United Launch Alliance Rocket Lab any of the Chinese missions you know I mean all there's countless it's it's insane it's hard to really really really hard to keep up with I wonder at which point in the future the number of launches to orbit will exceed the number of launches of airplanes like on the surface of Earth. Yeah, I have to admit I kind of have a hard time extrapolating out that far. You know, there's a lot of people that are like big futurists and really do think about like interplanetary stuff and think about colonizing Mars and stuff. I have a hard time predicting like when Starship's going to fly the orbital launch. You know, and that's like imminent ish like month or two scale time frame. And yet I'm still like I can't tell you when that's going. I can't tell you anything about like when we're going to land on Mars or what that's what that economy and what that you know the scale of launch operations is going to look like in order to do that because it's just so hard to I wouldn't have predicted where we're at today five years ago you know it's it's insane it's so hard to predict and. Yeah, but it's it's funny because there's so many like new companies starting up trying to predict that, and it's a really exciting you know startup culture right. I think when you make certain engineering decisions and hiring decisions and like what you focus on in terms of both business and engineering, it's good to think on the scale of 10, 20, 50, 100 years. That's one of the things that Elon is exceptionally good at, which is asking. The question: Okay, this might seem impossible right now, but what's the obvious way to do this if we look out 20 years? And then you start to make decisions. You start to make decisions about robotics, about brain computer interfaces, about space travel that are that make a lot of sense when you look at the scale of 10, 20, 50, 100 years and don't make any sense if you if you look at the scale of of just months. So but of course the actual work of day to day is focused on the next few months because there's deadlines, there's missions they have to accomplish. Anyway, we are returning back to the brief history of SpaceX rockets. Falcon Heavy. So what what else is there? So we talked about Falcon Nine and the rapid development there. What other flavors of a Falcon is there and how does that take us to Starship? Yeah, realistically, the Falcon Nine evolved more or less kind of like just got more powerful and a little bit longer and more capable. But nowadays they fly what's called the Block Five, even though it's like the eighth or ninth iteration of the of the Falcon Alpha. They call Block Five. It's the one that has the black landing legs, the black inner stage. They have a fleet of roughly 10 or so that are doing the majority of the leg work these days, and they're flying you know up to 15 times I think right now as the current booster leader. They're also recovering the fairings, so the nose cone of the rockets are frequently if not every time being recovered. Same with yeah, same with the booster for the most part, and the only thing being expended is the upper stage, and that's kind of where the Falcon Nine is ending. It really doesn't make sense to develop that infrastructure any longer. So they went with the next step, which is go even bigger. Physically, so they have more margin for upper stage usability, and that's what we see with Starship and Super Heavy. So the Super Heavy booster, the whole system is confusing. The whole system's kind of considered Starship, but technically the Starship is just the upper stage, which is also like the spaceship, which is also the upper stage, and then the booster itself is considered the Super Heavy booster. And that's what they've been working on. Publicly, it came out in 2016 as the at the time it was the ITS, the interplanetary transportation system. Later, and I think about 20 by the end of that year, 2017, it kind of became known as the BFR, the big Falcon rocket. Yes, yeah, and then I think it was about end of 2018 they started calling it Starship. But that is the that is where we're at today, and that's what they're working full steam ahead on. And what about Dragon? We mentioned Dragon, crew dragon, cargo dragon. Yeah, so they went from the cargo version of Dragon that flew about 20 times successfully to the International Space Station, except for that one CRS-7 where the rocket blew up in the capsule. Obviously didn't make it to the ISS. Then they went into the Dragon two, which has two variants. It has a crew variant, so we just call it crew dragon, and then there's the cargo version of of Dragon two, and that's just an updated, sleeker, sexier version of Dragon, and it's ironically it's heavier altogether. So it. You'll never see those those cool return to launch site landing. The boosters coming back to land for CRS missions anymore like we used to, but they landed on the drone ship anyway. And and yeah, that's been flying successfully. That's kind of the so there's yeah Starlink, Dragon, Falcon Nine, Falcon Heavy, and Starship system is kind of the whole. The whole SpaceX world really in terms of the the the spaceships involved. What do you are some of the major milestones in that history? We kind of mentioned a few. Yeah, sticking the landing is there something kind of stands out. Yeah, I would say definitely the big ones obviously like any of the first like the first flight of Falcon one, first flight of Falcon Nine, first time they went to the International Space Station. The first time they landed a booster, the first time they reused a booster, which is I think about six months after no, it was a year after it was SES 10, 2017. It was the first time they they reused one of those boosters, you know, and that was a big milestone. Like, can we even yeah, we recovered one we caught one, you know, it's like we got one now what. That was the first time they reflew one. Yeah, then flying humans was a huge one. DM two Bob and Doug for NASA. Bob and Doug, yeah, Bob and Doug. That was incredible. You know that was that was a huge huge step I think for SpaceX with flying people. So it's its first major commercial launching of humans out into space. Yeah, and not just into space because you know there's been people that have done you know space flights with you know like suborbital hops, but going into orbit and especially docking and rendezvous with the International Space Station is a it's a big deal. It's a whole. Until you really understand the physics involved and the scale involved of like just crossing the Carmen line going straight up versus going into orbit like they're just completely different things almost. What about Starship? Are we are we in a place where we can talk about milestones with Starship? Has there been or is it just been an epic journey of failures and successes of testing and and so on? Is there like yeah, what would you classify at this point as as a as a milestone that Starship or BFR whatever the name is was able to achieve. Well, so far the milestones we've seen, I'd say the first one would be the hop of they call it Star Hopper, and it's basically a very rudimentary rocket, but there was the first time they they utilized their new Raptor engine to produce thrust to to fly something. It first flew like literally like three meters off the ground or something like tethered to the ground, then it flew like 15 and then finally it flew 150 meters, and that was in 2019, and that was the first big milestone of Starship. And then after that, we saw SN5, SN6 kind of do the similar like 150 meter hops with a little bit more elegant systems. You know, proving out more of their their tank building, proving out more of their you know a lot of just subsystems, and then the big ones physically were in end end of 2020 and early 2021 when they flew the SN8, 9, 10, 11 and 15. What does the N stand for in SN? I think just serial number or serial number. Yeah, so SN these are just names numbers numerical representations of the different testing efforts. They skip some numbers, right? Yeah, if they if they scratch a test, yeah, and a lot of times it'd be like literally that they're building you know because at Starbase and what SpaceX is working on like the one foot is always in front of someone else's foot and like the arm is not knowing what the leg is doing sometimes. Yeah, they they will have someone working on you know they'll just be like, hurry up and build 40 of these tank sections and you build the bulkhead and you build the downcomer and you build the header tank, blah blah blah, and all of a sudden like oh we actually evolved that we don't use that header tank now so it's going to go onto this one so they'll have like parts of certain rockets built and it's like ah literally scrap it like not scrap it like in the you know joke term but like literally just go scrap it. And they so yeah they they just evolve and iterate so quickly. There were some epic explosions. I think Starship something about it probably just the amount of fuel just leads to some epic epic failures. Would you say Starship is the source of the most epic failures in terms of size of explosion? So you can literally measure in like a yield of explosive power, you know like like you could TNT. Like you can take a look at how much propellant is left over at the at the time of the explosion and you know Starship what's flown so far, even though it's physically one of the largest flying objects ever, just with the upper state alone, they've not filled it more than like 10 or 20 full of propellant. Yeah, and so it actually hasn't been the the failures have been really epic looking big visual fireballs, but in terms of space flight, they're still pretty small explosions, believe it or not. They could still go bigger. Oh, yeah, a lot, a lot. And of course, the test payload of a Tesla Roadster was launched. I forget what year that was. Yeah, that was 2018. That was quite epic. Would you put that on a milestone? Oh, yeah, yeah, Falcon Heavy demo was like definitely a a big, big, big milestone. Yeah, is that funny to you that there's a Roadster floating out there? Do we know the location of that Roadster at this? Oh, yeah, where is Roadster dot com? Yeah, oh yeah, where is it orbiting something? Yeah, it's orbiting the sun. So it's orbiting the sun and its orbit is basically between the Earth's orbit and beyond Mars. So I think of like 2. 5 AU if I remember right. So it's it's beyond Mars's orbit and its highest point and it's back at Earth kind of at its lowest point. I wonder if there's a mission where you're going to somehow connect with it once again and like place extra things into it. I wonder how challenging that is technically. Oh yeah, it could it could absolutely be done. You know the the hard thing at this point because it's on an eccentric orbit would be rendezvousing with it