HerbertAll right, well, hello everybody and welcome. Hang out. I got Elon and Ian Doll with our Starlink team. Figured we'd check in. It's been a typical SpaceX year. Launched a brand new vehicle. Acquired XAI, now SpaceX AI. Announced a terra-sized chip-building project. And so...
Elon MuskYeah, never a dull moment.
HerbertYeah, never a dull moment. Typical year. And so, kind of wanted to connect some of the dots on how this all feeds into making life multi-planetary, starting to climb up the Kardashev scale. Maybe show off some cool new AI sat stuff. Let's kind of start galaxy-sized and bring people in with the Kardashev scale. What's the big picture?
Elon MuskWhat's the big picture? What is the Kardashev scale? Like, how do you decide what progress a civilization has made? That's the most objective metric that any alien species, say visiting us, would use to calibrate how much progress we've made as a civilization. And one of the most objective ways to do that is the amount of power that any given civilization has been able to harness.
Elon MuskAnd there was a Russian physicist, actually, by the name of Kardashev, who thought about this, and it's a good way to characterize it, which is: you can assess how well a civilization is harnessing the power available on the planet. That's type one. And then type two would be how much of the star's power are you harnessing? And then type three would be how much of the galaxy's power are you harnessing? These are very objective and measurable numbers.
Elon MuskSo right now we're very low on the Kardashev one scale. Like, if you say what proportion of our planet's power are we harnessing, it's a very, very tiny number. And basically we're harnessing almost nothing of our star's power. So the sun is truly an immense thing. It is difficult with words to characterize just how immense the sun is, but this gives you sort of a sense of scale.
HerbertYeah, it's a big difficulty jump going from level one to level two.
Elon MuskVery big difficulty jump, yes. And level three, we don't even know how to do level three, really.
HerbertYeah, exactly. AI will figure it out, I suppose.
Elon MuskOne way to appreciate the size of the sun is to think about how heavy is the sun compared to all the rest of the mass in the solar system. So the sun is about 99.86% of all mass in the solar system. Everything, and then all the remaining 0.14%, most of that is Jupiter. One planet.
HerbertSo we're still lightweight.
Elon MuskYes. The entire mass of Earth is in the tiny miscellaneous category. Earth is a tiny dust mote compared to the sun.
HerbertWell, then how much energy are we talking, like coming from the sun, especially compared to what we're using here on Earth? It feels like...
Elon MuskYeah. The incident solar energy on the cross-section of the Earth is roughly a half billionth of the sun's power output. And the vast majority of that we cannot use because, you know, 70% of Earth is water, which technically our planet should be called Water, because it is 70% water. I think an alien civilization visiting us would be like, "Why are they calling it Earth when it is mostly water?"
HerbertWe're the Greenland's-not-green of the galaxy, of the solar system.
Elon MuskYeah. Exactly. You know, we're 70% water. And then of the 30% that's land, a bunch of it is Antarctica or Siberia type of thing, very northern Canada type of thing. Not places people typically want to live, and you're not going to get a lot of solar power at the poles. So the actual usable area of land where you can get solar power is quite small.
Elon MuskAnyway, in order to ascend the Kardashev scale, or in order to get to any meaningful percentage of the sun's energy harnessed, you have to go to space. If you want to get to, say, a millionth of the power output of the sun, you would have to increase civilizational energy harnessed by much more than a million. So we currently use much less than a trillionth of the power output of the sun. And a trillion is a million times a million. So basically there's... we're practically nowhere on the sort of Kardashev two scale. Practically nowhere.
HerbertSo on the Kardashev scale, we're all still... we're still non-existent.
Elon MuskWe're non-existent. We're like not even... we're not even... yeah, we're so... we're not registering.
HerbertNot even a micro soul.
Elon MuskYeah. No. And so to actually... a soul would be an epic, epic achievement relative to where we are right now.
HerbertSomething to aspire to.
Elon MuskYeah, that's our goal. And I think this was simultaneously an incredibly adventurous goal relative to where we are, and yet not particularly adventurous as a percentage of the sun's energy to try to achieve, power harnessed being one millionth of what the sun outputs.
HerbertA micro soul.
HerbertTo actually start getting there though, we're not just going to throw solar arrays in space, try to soak up a bunch of the sun. Like, there has to be a need. We want to go up there and do something meaningful. And obviously until this point in human history, there hasn't really been a need. What has changed to make us think that maybe now's the time to start trying to notch our percentage point or two?
Elon MuskI mean, getting to a percent of the sun's energy... maybe not a percent.
HerbertLet's move the decimal point back a couple years.
Elon MuskIt's an extremely kick-ass civilization if you get to 1% of the sun's energy. I'm like, wow. That civilization is going to be vastly more powerful than us, to say the least.
Elon MuskSo in order to start to make some progress on the Kardashev scale, we need to launch satellites to orbit Earth and capture solar power. That avoids the need to build massive power plants on Earth and deal with cooling, because cooling is actually much easier in space than it is on Earth. You can just radiate to the vacuum.
Elon MuskAnd so what we're proposing here, and what we intend to do, is to try to climb the Kardashev scale to kind of like a respectable civilization. So when the aliens, hopefully there are aliens out there, and they maybe finally decide to talk to us, you know, we have some respectable amount of the sun's energy being used. That's not, like, totally pathetic, which is the current situation.
HerbertAnd so before we start sending data centers, sending all this to space, there are some limiting factors that we got to get through that would traditionally make it so like this is almost impossible. What does it take to scale?
Elon MuskYeah. So things it takes to scale are: you need to have a large mass-to-orbit capability, which is what Starship will give us. That large mass... you know, we ultimately need to send millions of tons to orbit and beyond. And you need the power associated with that. So if you want to put 100 gigawatts, or ultimately a terawatt, into space from Earth, you will at some point need a terawatt of solar.
Elon MuskAnd then you're going to need a terawatt of AI chips. So the three things you need are mass to orbit, a lot of solar power, and radiators of course. And a lot of chips.
HerbertAll right, well, let's start ticking down the list. So mass to orbit, that's where Starship comes in. Yeah, we just had first flight V3, it's awesome. I know you were there. It was crazy to see that rocket launch. And, like, long time coming. What's Starship's kind of purpose of being? What is it going to be doing?
Elon MuskYeah, so Starship is going to revolutionize space, really. It's the first rocket design that is capable of full and rapid reusability. Now, reusability is the fundamental breakthrough that is necessary to make life multi-planetary, as well as to ascend the Kardashev scale. You simply cannot ascend the Kardashev scale unless you have a reusable spacecraft, and you cannot extend life to the moon, to Mars, and to the rest of the solar system without a reusable rocket. The cost is simply prohibitive. You can't make enough rockets unless you can re-fly them.
Elon MuskJust like any other mode of transport, you can imagine that if we had to throw away airplanes every time we flew, flying would be far too expensive and basically no one would be flying airplanes. You'd be doing a whole lot more driving.
HerbertRapid reusability.
Elon MuskYes. (Laughter) Every mode of transport is reusable, without which it's simply not viable as a transport system. So cars, planes, boats, horses, bicycles are all obviously reusable. With rockets, it's much harder to make a rocket reusable because Earth has a deep gravity well and a thick atmosphere. And these make it just barely possible to achieve reusability with a rocket.
Elon MuskAnd there've been, you know, many prior attempts to create a fully reusable rocket. And most of those attempts have been abandoned halfway through because they didn't think they could succeed. In order to achieve full reusability, everything's got to be perfect. It's the engines, the structure, the avionics, the choice of propellants. You've got to go to extreme measures for mass optimization, which is why we have the tower catch the rocket instead of putting on landing legs, which are heavy. The rocket can simply be caught by the tower.
Elon MuskAnd we haven't achieved full reusability yet, but we do expect to achieve that hopefully later this year with Starship. And then you've got to go a step beyond that, which is make it rapidly reusable, such that the rocket lands, it gets caught by the tower, gets put back on the launch stand, and can be flown again without any refurbishment or laborious inspection, like an aircraft. This is incredibly difficult. This is the first time that there's ever been a rocket where that is possible.
Elon MuskThat's what makes Starship so profound. I mean, it also happens to be the largest flying object ever made, the heaviest flying object ever made, the most powerful moving object of any kind. You know, Starship V3 is more than double the thrust of the Saturn V moon rocket. By version 4 it will be pretty much three times the thrust of the Saturn V moon rocket. And we expect Starship to be flying more than once per hour down the road.
HerbertOne of the fun facts from flight 12, that was actually the heaviest payload SpaceX has ever flown, and that's still just a fraction of what V3 can do. So...
Elon MuskYes. I mean, once we're flying massive amounts really rapidly... I mean, we already fly the majority of payload to space with Falcon.
HerbertDo people even really understand what mass to orbit becomes once Starship is flying?
Elon MuskIt's many orders of magnitude greater than what is the case today. So even with Falcon 9, Falcon Heavy, SpaceX delivers almost 90% of all Earth mass to orbit. I think it's somewhere between 85 and 90% right now. And then most of the remaining mass, I think, is launched by China, and then the rest of the world, including the rest of the US, is the remaining, I don't know, 5 to 7%.
Elon MuskNow with Starship, we'll be aiming to go from somewhere around 2,500 tons a year to orbit to millions of tons per year to orbit. And to do so in a pretty short period of time. So we think probably we can get to a million tons to orbit per year in about 3 years, thereabouts.
HerbertStarship is going to take care of the mass-to-orbit limiting factor.
Elon MuskYes.
HerbertAnd then power generation. So first... and Ian, maybe you can help.
Ian DollSure.
HerbertPeople probably struggle to visualize a little bit when you say, like, data center in space. Like, we're not going to slap engines on a building and fly it up. These actually look pretty different. And so kind of walk through how you take something that's in a giant building on the ground and turn it into something that's functional in space.
Ian DollYeah, I think it's pretty interesting. A lot of people don't actually know what the inside of a data center even looks like, right?
HerbertYeah.
Ian DollAnd it's some, like, mythical place where the internet's in the cloud or something.
Ian DollYeah, some people envision wires, some people envision boxes, but effectively it comes down to a set number of chips. And the things that we need to launch into space are actually quite small when we look at it. The more challenging part is figuring out how do you get the power for it? And that's where a lot of what we've worked on for existing Starlink technology, the solar arrays, are what we want to utilize—that expertise—to be able to build a satellite that can actually launch the critical components of the data center into space itself.
Ian DollWe like to look at this and say, like, what is the actual engineering problem here? And it's really a combination of delivering power and then taking the waste heat and energy away and sending it into the vacuum of space, as you mentioned.
Elon MuskYeah. The AI satellite is actually much simpler than a Starlink satellite. A Starlink satellite has gigantic phased array antennas. It's got parabolic antennas, it's got a lot of laser links. It's much more complicated than an AI satellite. An AI satellite is essentially a lot of solar cells, a radiator, and you still need some laser links, but you don't have all of the super complex antennas that you have on a Starlink satellite. So, given the two, the easier one to design for is the AI satellite.
Ian DollYeah. It's just a little bit bigger.
Elon MuskIt's bigger. Just make stuff bigger, yeah.
HerbertI was like, so we've got this, this is our AI one. If you guys want to walk us through.
Ian DollYeah, so the first thing that we're really looking at here is, like, first you got to make something compelling, right? And we thought that the right place to start is around the 150 kW peak power level. But as we look at the workloads, with our experience with XAI, we get to actually see... we can also support about 120 kW of average compute. There's a difference.
Elon MuskYes. And what we're showing here is kind of a draft version of version one of the SpaceX AI satellite. The AI one, I guess you could call it. And seems like a reasonable place to start is 150 kW peak power, 120 kW sustained power.
Ian DollAnd to give you a sense of what does that actually look like in terms of the size of the radiators, size of the solar panels: the assumptions here are 250 W per square meter for the solar array, and about 1,400 W per square meter for the radiators. So the radiators—these are double-sided. Radiators are radiating both sides. They're oriented knife-edge to the sun. And 1,400 W per square meter is a very achievable goal.
Ian DollOver time, we think we can probably do above 250 watts per square meter and above 1,400 watts per square meter for the solar panels and radiators respectively. But this gives you, like, pretty much what the satellite's going to look like. It's a lot of solar panels, radiator, and then everything else is pretty small by comparison. And these are like evolutions of things that we have actually already launched in our Starlink constellation to date.
Ian DollYeah. That's really, I think, the cool part to me, is that we're looking at solar technology that we already are going to use on the V3 Starlink vehicle. So I'm really excited to then just take those and make it bigger.
Elon MuskYeah. Part of what we want to convey here is that there's not some magic that's necessary that doesn't exist for the AI satellites. As Ian said, a lot of this is technology that we've already made for the Starlink V3 satellites. So we basically don't think this is a super hard problem compared to things we already do.
Elon MuskThere would also be probably something on the order of a terabit of laser link connectivity from the satellite. The 150 kilowatt peak power level roughly matches what an Nvidia GB300 rack would do. So if you've got a GB300 with 72 GPUs, its peak power, I think, is around 140 kilowatts. But it's almost impossible to get it to be at that peak power. A more reasonable operating envelope would be around 120 kilowatts average power. But it can peak up to 150.
Elon MuskSo basically think of it as a rack of compute in space. And then you can connect these racks of compute either to each other by the laser links, or directly to the Starlink constellation. So you can close the link with the Starlink constellation, and then Starlink can then send that data to the ground using the existing KA and KU antennas on the vehicle. It also has laser-to-laser links to the ground as well.
Elon MuskAnd this would not be at a particularly high latency. You know, we're talking about maybe being around 600 to 800 km above the Earth, and light travels 300 km per millisecond. So that's about, you know, 3 milliseconds away basically. It's not very far.
HerbertWon't worry about that too much then. Sometimes people worry, think it's going to be some, like, high latency. I'm like...
Elon MuskYeah, it's no, speed of light moves pretty fast.
HerbertLight moves pretty fast. It's all one.
Elon MuskYeah.
Ian DollI think the cool thing also is the radiators themselves are about the same size as the existing solar arrays for the V3 vehicle. Kind of in that realm where we're flying today.
HerbertYeah. So, I mean, they got about a 70 m wingspan. So these are fairly large. We're talking about building a lot of them and putting them up there, but, like you say, space is in the name. There's a lot of space up there. And so even when you're talking thousands or even, you know, up to a million satellites, you got plenty of room to move around up there.
Elon MuskYeah, space is really big. So it's not like space is going to get crowded. Space is enormous. If you zoom in close to the satellite, it looks big, but if you actually look at it relative to the Earth, these satellites are so tiny, you can't even see them. They're very, very tiny compared to Earth.
HerbertAnd, I mean, we have about 10,000 Starlinks in orbit right now. We've got a pretty good idea of how to operate just really large constellations and do it safely now, right?
Ian DollWe are the only operator that has any experience at that scale. It's a great thing that, you know, we have this background, so we know how tightly we can pack the satellites and fly them safely. That's a number one goal when we look at the constellation.
HerbertWe're going to be building a lot of satellites, and we're going to be building them here in Bastrop, right? So we've got this, which...
Ian DollYeah.
HerbertSo we're in that building kind of in the middle, which...
Ian DollYeah, we're sitting in that building right now.
HerbertThis is my first time here. The building is massive. Like, you come around the corner, you see it through the trees and you're like, "Oh, wow." But we're about to kind of put this building to shame, aren't we?
Ian DollUh, yes, we're going to...
Elon MuskIn fact, we already have the solar manufacturing facility, satellite construction already. And then we will be building out the AI sat production building soon. So we expect to have the AI sat production, the solar production, and all of that operating at some reasonable volume by the end of next year.
Ian DollSo if anybody wants to work on AI satellites, this is kind of going to become the hub of that. We're also... So, I mean, like, right behind us the machines are humming. We're still making all of our user terminals for Starlink here. That's not going anywhere. In fact, we're turning on new production lines for new units, right?
Elon MuskUh, yes. In fact, these are the new Starlink terminals, which we made in much higher volume than the current terminals. You know, ultimately we think there's probably going to be a few hundred million Starlink terminals out there. And then our Starlink direct-to-cell constellation will connect directly to people's cell phones and enable high-bandwidth communication directly from your phone to space.
HerbertAll right. We're two limiting factors down. We've got mass to orbit. Got putting solar in the few... third one's chips.
Elon MuskYes. So at least in the beginning we can obviously launch the chips that are already being made. So our current reference design is for Nvidia Rubin chips, or could be either GB300 or Rubin chips. And we'll also have a reference design for TPUs, and essentially you can put up any existing chips into orbit.
Elon MuskBut the current industry seems like it's going to get to maybe around a hundred gigawatts a year of AI compute. But that doesn't answer the question of, well, how do you get to a terawatt? That's why you need the terafab.
HerbertAlways looking a step bigger. Yeah.
Elon MuskYeah, in order to get to the next order of magnitude you need a gigantic chip factory. To give you a sense of scale here, we expect that the terafab is going to be around a hundred million square feet, which is ten times the size of the Tesla Gigafactory Texas.
HerbertAnd aside from just, you know—I'm going to need Starship point-to-point to get from one end to the other—aside from just the size, what's going to make this unique, different from any other chip-building operation on the planet?
Elon MuskWell, I think over time there's going to be a lot of technology evolution with the terafab. But fundamentally, it's about scale. So even if there were no fundamental technology breakthroughs, you could simply scale the existing chip-making technology, with a lot of difficulty, to a terawatt of chip output per year. If you look at it just from the logic die standpoint, that's equivalent to having a billion chips per year with a kilowatt per reticle. So there's a billion full-reticle-equivalent chips, each doing a kilowatt. And then you're going to need a lot of memory to go with that.
HerbertA lot of people today even think orbital data centers were, like, a decade away.
Elon MuskYeah, I think we want to try to give people a sense of the time frame. At least the time frame we're aiming for. I mean, you know, people should take this with a grain of salt to some degree, because this is just our best guess. So this is not a promise of what we'll do. This is what we are going to try to do and think we probably can do.
Elon MuskWhich is to get to roughly an annualized rate of a gigawatt per year by the end of next year in terms of space AI compute. And then, aspirationally, scale that by an order of magnitude per year. So in two and a half years, hitting an annualized rate of 10 gigawatts a year to space; in three and a half years, maybe 100 gigawatts; and then, depending upon what progress there is in chip-making in the rest of the world, and with the terafab, going beyond that to scale to a terawatt per year, which is 1,000 gigawatts.
HerbertWhich is twice the current electricity consumption of the United States.
Elon MuskYeah. I think there will be an appetite for that, but we'll see. It's a lot of satellites. I don't know what he's going to think about, but we need to do a lot of simulations or something.
HerbertYeah. So, after we've, you know, worked through all the limiting factors, we've kind of topped out what we can do on Earth, what is the next step to, again, try and actually notch maybe some percentage points towards becoming Kardashev level two?
Elon MuskWhy stop there? Why think small? Because a terawatt actually is very small.
HerbertThink small. Let's not think small.
Elon MuskSo there is, in order to get to another three orders of magnitude, to 1,000X from a terawatt per year, the only way that we can really see that you can achieve that is on the moon with a mass driver. Essentially, where you do local production of photovoltaics and solar and radiators on the moon. Maybe you bring the chips from Earth, or you could conceivably make the chips on the moon. But you need most of the mass to be made on the moon, so you don't have to transport it to the moon from Earth.
Elon MuskAnd then, because the moon has no atmosphere and only 1/6 Earth's gravity, you can accelerate the AI satellites into deep space without a rocket. So you can basically shoot them into space using an electromagnetic gun, like a rail gun type... I mean, it's basically a linear electric motor is the way to think about it. As a way, I think we can show people.
HerbertI mean, if that doesn't get you excited for the future, I don't really know what will. I'm fired up to see a mass driver on the moon. That'd be very cool.
Elon MuskYeah.
HerbertSci-fi future.
Elon MuskYeah. It would also mean that if we're bringing that amount of mass to the moon, it would mean that anyone who wants to go to the moon will be able to go to the moon. And I think that would be pretty cool.
HerbertYeah. I'm going to be jumping first in line to get up there for that.
Elon MuskI think everyone should go to the moon at least once, I think.
HerbertJust once, yeah.
Elon MuskYou can move there if you want. You can go live on the moon.
HerbertWe'll see. Thanks, guys, for chatting with me for a little bit.
Elon MuskAll right.
HerbertMan, excited to see a whole new tech, whole new kind of satellite, whole bunch more Starship launches, more chips, more solar, more, more everything. It's a big future, but I'm excited to see everybody at this company go out and build.
Elon MuskAll right, sounds good. It's exciting. Thanks, guys.