6 ms·

The orbital data center thing is really strange. Without some kind of massive technological breakthrough the physics of an orbital data center make no sense. Na

The orbital data center thing is really strange. Without some kind of massive technological breakthrough the physics of an orbital data center make no sense. Napkin math for a single data center including solar panels, radiators, compute and structure is somewhere on the order of ~6500 tonnes. Let's say Starship can put 100-150 tonnes into orbit per launch, that is somewhere between 40-65 launches for just one single orbital data center.

jiggawatts 4mo ago
The actual “plan” is to just put a couple of GPUs in each Starlink satellite for inference. They’re not launching something the size of a building!
- kldavis4 4mo ago
  That just doesn't seem to justify anywhere near the valuation though does it?
  - jbxntuehineoh 4mo ago
    shhhhhh the line WILL go up, whether you like it or not
  - jiggawatts 4mo ago
    Disclaimer: I suspect "data centers in space" is just blatant market manipulation by Elon, exactly the same as he'd done dozens of times before with self-driving, etc. Having said that... it might justify the valuation if every other data centre build-out gets blocked by insufficient power supply. Might.
    - fc417fc802 4mo ago
      Bear in mind that you could take the solar panels that you would have launched into orbit, use the launch costs to purchase additional solar panels, batteries, and some additional land, and build a data center plus solar farm plus grid scale battery bank on the ground for probably (almost certainly) less than the combined launch costs. I think the only way compute in space works out financially is if there's so much bulk data already up there that downlink bandwidth becomes a serious bottleneck.
- SwellJoe 4mo ago
  Which is irrelevant to SpaceX bottom line. Launching GPUs into space, whether by twos or by tons is not going to be a profitable venture. It's just a wildly expensive bad idea, and it is obvious to anyone that understands how much it costs to put things in space. A man who runs a rocket company knows how much it costs. He knows it's dumb as hell. But, he also knows the average investor is even dumber, because TSLA still trades at ~357 PE.
credit_guy 4mo ago
> Let's say Starship can put 100-150 tonnes into orbit per launch, that is somewhere between 40-65 launches for just one single orbital data center. Ok. And why does it follow from this that the physics of an orbital data center makes no sense?
- adgjlsfhk1 4mo ago
  Because 50 rocket launches seems hard to make cheaper than a building.
  - tekla 4mo ago
    The cheapness of the building is not the problem that is being dealt with. The construction of the building w/ zoning and the political fights and utilities arguments and years of time and whatever is what is being dealt with by putting it in orbit.
    - ink_13 4mo ago
      I bet you could build a fully off-grid DC that didn't guzzle water for less money than launching a rocket today, and there would be thousands of people lining up down the block to sell you more than enough land to do it a thousand times for cheap. This just isn't happening yet because it is still quite possible to build on-grid DCs supplied with fresh water for cooling despite what some people would have you believe. And then when you build on the ground you could even send people to it to swap hard drives and GPUs when they inevitably fail or upgrade them to keep them current. At lower rates of failure than they would in space because we have a planetary magnetosphere protecting us from cosmic rays.
    - kaashif 4mo ago
      It would be extremely funny if putting things in space is cheaper and faster than dealing with zoning and local politics. It implies that China, which can cut through much red tape and has great (and improving) utilities and infrastructure, lots of energy, can just build normal datacenters and save the cost of dozens of space flights.
hparadiz 4mo ago
The video they posted today outlines their specs. They are gonna be smaller. About 100T. Based on Starlink architecture but with way larger radiators and solar panels. Apparently the design is simpler than existing Starlinks because it has fewer different parts. Specs: https://x.com/SawyerMerritt/status/2064108916611420273?s=20 https://x.com/SawyerMerritt/status/2064108916611420273?s=20
- pryce 4mo ago
  I feel like we are going to relive the hyperloop-decline with the specs of proposed orbital datacentres. But the hyperloop was in one regard a success, in that it built temporary hype. Maybe it was even named after that.
  - SwellJoe 4mo ago
    It also achieved Musk's actual goal: derailing and delaying mass transit initiatives, the California High-speed Rail project, in particular. He knew it was bullshit. He's dumber than most people realize, but he's not dumb enough to actually believe all the bullshit he spouts.
    - hparadiz 4mo ago
      He's sending the weirdest mixed signals. If we want to hit anywhere near 1 on the Kardashev scale we're gonna need a planet wide high speed rail system. They should just give the major tech companies naming rights to the stations for 35 years for like 2-3 billion a pop and scale up construction 5x. I don't get the slow roll on this thing. The stations in LA and SF are gonna end up sort of like Tokyo station for the Shinkansen. A giant mall area with a huge amount of commerce. Why isn't this thing done yesterday?
      - nine_k 4mo ago
        > Why isn't this thing done yesterday? Land rights. Environmental reviews. Various suits attempting to exert extra compensations for tangential (at best) issues. Basically the California around.
datadrivenangel 4mo ago
They'll do smaller satellites, and if they can get an order of magnitude improvement on cooling and power generation to weight ratios, it'll be close to the same order of magnitude cost-wise as a terrestrial datacenter. 10x the cost is likely not enough to make it all work, so it's a bad idea, but it's possibly less bad than using lead ballast for starship launches... maybe.
- toomuchtodo 4mo ago
  “Supervised Full Self Driving.” Buy the hope, sell reality.
- jmalicki 4mo ago
  Is there some reason significant improvement on cooling and power generation to weight generation ratios is even remotely possible?
  - datadrivenangel 4mo ago
    Better integration allows for a lot of potential improvements, so if the cooling and power and compute are tightly integrated and use structural materials it may be plausible. Still not going to be cheaper, but if you get moderately optimistic it's cheap enough to maayyyybe start looking like a source of demand for starship if you can find suckers (government) to pay 10x the price per compute.
- amluto 4mo ago
  I still don’t see it. The equipment is very, very expensive, is subject to shortages, and has residual value after five years. But these very low Earth orbit satellites literally burn up when they run out of fuel for station keeping. Even if you pay a bit more to position them in a higher, more stable orbit, you still can’t physically get to them to repurpose equipment. Check this datacenter gadget out: https://www.marvell.com/blogs/sustainable-computing-with-cxl.html https://www.marvell.com/blogs/sustainable-computing-with-cxl... That trick is a complete nonstarter if the modules you’re trying to reuse are in space.
overgard 4mo ago
I'm pretty sure he's full of shit and has zero real intention of building orbital data centers. It makes for a good headline, which is what these AI companies are in the business of. The math doesn't math and the logistics of maintaining and building the datacenter seem insane.
- ericd 4mo ago
  They claim they want to get to a gigawatt per year by the end of next year, so we won't have to wait long to see.
  - bandrami 4mo ago
    He also claimed in 2015 that nobody would be driving their own cars by 2018. Meanwhile I've seen a driverless car once in my life.
    - ericd 4mo ago
      Sure, I think everyone knows he's not batting 1000. I've used Waymos and FSD, and they were both great, so I don't think we're too far off now.
      - Sammi 4mo ago
        My man, it's 2026. How long will you have to wait for the spacex claims to become "not too far off now"?
        ericd 4mo ago
        Which claims? I’ve been a SpaceX investor for about 8 years now, I’m completely satisfied with their progress, even despite the Starship setbacks, they’ve done astounding work on all fronts. I’m not holding my breath for humans on Mars or us becoming a Kardashev 2 civilization, if that’s what you’re asking.
        4mo ago
JoshTko 4mo ago
It's a litmus test of who understand basic physics and thermodynamics
vagab0nd 4mo ago
I think it comes down to scaling and removing the bottlenecks. If you build one data center on earth, you did just that. If you build one in space and make it work and cost effective, you can scale infinitely (which is why SpaceX is uniquely positioned), until you hit the next bottleneck (which is why Tesla is building a fab). Tangential: If you play Factorio or Satisfactory, this is _all_ you do. Removing bottlenecks.
- lenerdenator 4mo ago
  > If you build one in space and make it work and cost effective, you can scale infinitely "If we can just keep consuming massive amounts of capital, at some point, we'll turn a profit. Maybe even a big one." It's not 2019 anymore, but this mindset acts like it still is. SpaceX, along with its wanna-IPO classmates OpenAI and Anthropic, are going public because there's basically no more private investor money left and there's no political will (outside of whatever the hell is going on in Donald Trump's head) to lower interest rates to what they were in the golden age of blitzscaling. They have to ask the public for more money. They just don't have enough humility to do it on decent terms, as evidenced by the IPO deals they're floating. If this fails to produce what you're talking about - which is likely given things like "speed of radio transmissions", "thermal conductivity in a vacuum" and other things governed by those pesky laws of physics - the game's over.
numpad0 4mo ago
There are people arguing it has to be a signal processing backend for a realtime radar system based on Starlink Direct-to-Cell antennas. IMO, that lines up with a weird remark from Musk around stealth jet obsolescence few years ago, and makes sense.
wmf 4mo ago
I see it as a hedge against NIMBYs. If terrestrial data centers literally can't be built then orbital is cheaper by definition. If not, just don't build them.
- Atotalnoob 4mo ago
  Worse, it’s “don’t worry, the next data centers will be in space, so it’s okay if the ones we are building right now destroy the environment, there won’t be anymore!” It’s the exact tactic he used with California HSR
  - wmf 4mo ago
    I don't see anyone making that argument and we shouldn't allow it. The "temporary" generators are bad enough.
fc417fc802 4mo ago
I think that's looking at it the wrong way. Just view it as a fleet of satellites with computers in them that exist for the purpose of selling capacity. I don't see any issues with the physical fundamentals but the economics in terms of dollars either per flop or per bit transferred is where I don't understand how it's supposed to work. Satellites are really expensive and electricity on the surface is relatively cheap. What hypothetical prospective customers are willing to pay the necessary rates? I understand that bandwidth back to the surface is expensive but are we really expecting so much raw data to be trapped in space that it justifies sending computers into orbit in order to crunch it at the source?
- queenkjuul 4mo ago
  The physical fundamentals don't work. Radiating exhaust heat is exponentially harder in space than in the atmosphere.
  - fc417fc802 4mo ago
    What is the equilibrium temperature of a panel of black sheet metal hanging out at an orbit of 1 AU? Because if the thing is solar powered then it cannot exceed that temperature on average (ie across the entire mass) due to energy being conserved. You can do goofy things like using solar power coupled with a heating element (such as a GPU) to shift more heat to one part of the panel or another (ie employ an insufficient heat spreader design) but you fundamentally cannot exceed the equilibrium temperature on average.
    - queenkjuul 4mo ago
      Well the equilibrium temperature of outer space is roughly 0K. So how do you remove megawatts of heat in 0K?

jiggawatts 4mo ago

The actual “plan” is to just put a couple of GPUs in each Starlink satellite for inference. They’re not launching something the size of a building!

kldavis4 4mo ago
That just doesn't seem to justify anywhere near the valuation though does it?
- jbxntuehineoh 4mo ago
  shhhhhh the line WILL go up, whether you like it or not
- jiggawatts 4mo ago
  Disclaimer: I suspect "data centers in space" is just blatant market manipulation by Elon, exactly the same as he'd done dozens of times before with self-driving, etc. Having said that... it might justify the valuation if every other data centre build-out gets blocked by insufficient power supply. Might.
  - fc417fc802 4mo ago
    Bear in mind that you could take the solar panels that you would have launched into orbit, use the launch costs to purchase additional solar panels, batteries, and some additional land, and build a data center plus solar farm plus grid scale battery bank on the ground for probably (almost certainly) less than the combined launch costs. I think the only way compute in space works out financially is if there's so much bulk data already up there that downlink bandwidth becomes a serious bottleneck.
SwellJoe 4mo ago
Which is irrelevant to SpaceX bottom line. Launching GPUs into space, whether by twos or by tons is not going to be a profitable venture. It's just a wildly expensive bad idea, and it is obvious to anyone that understands how much it costs to put things in space. A man who runs a rocket company knows how much it costs. He knows it's dumb as hell. But, he also knows the average investor is even dumber, because TSLA still trades at ~357 PE.

credit_guy 4mo ago

> Let's say Starship can put 100-150 tonnes into orbit per launch, that is somewhere between 40-65 launches for just one single orbital data center. Ok. And why does it follow from this that the physics of an orbital data center makes no sense?

adgjlsfhk1 4mo ago
Because 50 rocket launches seems hard to make cheaper than a building.
- tekla 4mo ago
  The cheapness of the building is not the problem that is being dealt with. The construction of the building w/ zoning and the political fights and utilities arguments and years of time and whatever is what is being dealt with by putting it in orbit.
  - ink_13 4mo ago
    I bet you could build a fully off-grid DC that didn't guzzle water for less money than launching a rocket today, and there would be thousands of people lining up down the block to sell you more than enough land to do it a thousand times for cheap. This just isn't happening yet because it is still quite possible to build on-grid DCs supplied with fresh water for cooling despite what some people would have you believe. And then when you build on the ground you could even send people to it to swap hard drives and GPUs when they inevitably fail or upgrade them to keep them current. At lower rates of failure than they would in space because we have a planetary magnetosphere protecting us from cosmic rays.
  - kaashif 4mo ago
    It would be extremely funny if putting things in space is cheaper and faster than dealing with zoning and local politics. It implies that China, which can cut through much red tape and has great (and improving) utilities and infrastructure, lots of energy, can just build normal datacenters and save the cost of dozens of space flights.

hparadiz 4mo ago

The video they posted today outlines their specs. They are gonna be smaller. About 100T. Based on Starlink architecture but with way larger radiators and solar panels. Apparently the design is simpler than existing Starlinks because it has fewer different parts. Specs: https://x.com/SawyerMerritt/status/2064108916611420273?s=20 https://x.com/SawyerMerritt/status/2064108916611420273?s=20

pryce 4mo ago
I feel like we are going to relive the hyperloop-decline with the specs of proposed orbital datacentres. But the hyperloop was in one regard a success, in that it built temporary hype. Maybe it was even named after that.
- SwellJoe 4mo ago
  It also achieved Musk's actual goal: derailing and delaying mass transit initiatives, the California High-speed Rail project, in particular. He knew it was bullshit. He's dumber than most people realize, but he's not dumb enough to actually believe all the bullshit he spouts.
  - hparadiz 4mo ago
    He's sending the weirdest mixed signals. If we want to hit anywhere near 1 on the Kardashev scale we're gonna need a planet wide high speed rail system. They should just give the major tech companies naming rights to the stations for 35 years for like 2-3 billion a pop and scale up construction 5x. I don't get the slow roll on this thing. The stations in LA and SF are gonna end up sort of like Tokyo station for the Shinkansen. A giant mall area with a huge amount of commerce. Why isn't this thing done yesterday?
    - nine_k 4mo ago
      > Why isn't this thing done yesterday? Land rights. Environmental reviews. Various suits attempting to exert extra compensations for tangential (at best) issues. Basically the California around.

datadrivenangel 4mo ago

They'll do smaller satellites, and if they can get an order of magnitude improvement on cooling and power generation to weight ratios, it'll be close to the same order of magnitude cost-wise as a terrestrial datacenter. 10x the cost is likely not enough to make it all work, so it's a bad idea, but it's possibly less bad than using lead ballast for starship launches... maybe.

toomuchtodo 4mo ago
“Supervised Full Self Driving.” Buy the hope, sell reality.
jmalicki 4mo ago
Is there some reason significant improvement on cooling and power generation to weight generation ratios is even remotely possible?
- datadrivenangel 4mo ago
  Better integration allows for a lot of potential improvements, so if the cooling and power and compute are tightly integrated and use structural materials it may be plausible. Still not going to be cheaper, but if you get moderately optimistic it's cheap enough to maayyyybe start looking like a source of demand for starship if you can find suckers (government) to pay 10x the price per compute.
amluto 4mo ago
I still don’t see it. The equipment is very, very expensive, is subject to shortages, and has residual value after five years. But these very low Earth orbit satellites literally burn up when they run out of fuel for station keeping. Even if you pay a bit more to position them in a higher, more stable orbit, you still can’t physically get to them to repurpose equipment. Check this datacenter gadget out: https://www.marvell.com/blogs/sustainable-computing-with-cxl.html https://www.marvell.com/blogs/sustainable-computing-with-cxl... That trick is a complete nonstarter if the modules you’re trying to reuse are in space.

overgard 4mo ago

I'm pretty sure he's full of shit and has zero real intention of building orbital data centers. It makes for a good headline, which is what these AI companies are in the business of. The math doesn't math and the logistics of maintaining and building the datacenter seem insane.

ericd 4mo ago
They claim they want to get to a gigawatt per year by the end of next year, so we won't have to wait long to see.
- bandrami 4mo ago
  He also claimed in 2015 that nobody would be driving their own cars by 2018. Meanwhile I've seen a driverless car once in my life.
  - ericd 4mo ago
    Sure, I think everyone knows he's not batting 1000. I've used Waymos and FSD, and they were both great, so I don't think we're too far off now.
    - Sammi 4mo ago
      My man, it's 2026. How long will you have to wait for the spacex claims to become "not too far off now"?
      - ericd 4mo ago
        Which claims? I’ve been a SpaceX investor for about 8 years now, I’m completely satisfied with their progress, even despite the Starship setbacks, they’ve done astounding work on all fronts. I’m not holding my breath for humans on Mars or us becoming a Kardashev 2 civilization, if that’s what you’re asking.
        4mo ago

JoshTko 4mo ago

It's a litmus test of who understand basic physics and thermodynamics

vagab0nd 4mo ago

I think it comes down to scaling and removing the bottlenecks. If you build one data center on earth, you did just that. If you build one in space and make it work and cost effective, you can scale infinitely (which is why SpaceX is uniquely positioned), until you hit the next bottleneck (which is why Tesla is building a fab). Tangential: If you play Factorio or Satisfactory, this is _all_ you do. Removing bottlenecks.

lenerdenator 4mo ago
> If you build one in space and make it work and cost effective, you can scale infinitely "If we can just keep consuming massive amounts of capital, at some point, we'll turn a profit. Maybe even a big one." It's not 2019 anymore, but this mindset acts like it still is. SpaceX, along with its wanna-IPO classmates OpenAI and Anthropic, are going public because there's basically no more private investor money left and there's no political will (outside of whatever the hell is going on in Donald Trump's head) to lower interest rates to what they were in the golden age of blitzscaling. They have to ask the public for more money. They just don't have enough humility to do it on decent terms, as evidenced by the IPO deals they're floating. If this fails to produce what you're talking about - which is likely given things like "speed of radio transmissions", "thermal conductivity in a vacuum" and other things governed by those pesky laws of physics - the game's over.

numpad0 4mo ago

There are people arguing it has to be a signal processing backend for a realtime radar system based on Starlink Direct-to-Cell antennas. IMO, that lines up with a weird remark from Musk around stealth jet obsolescence few years ago, and makes sense.

wmf 4mo ago

I see it as a hedge against NIMBYs. If terrestrial data centers literally can't be built then orbital is cheaper by definition. If not, just don't build them.

Atotalnoob 4mo ago
Worse, it’s “don’t worry, the next data centers will be in space, so it’s okay if the ones we are building right now destroy the environment, there won’t be anymore!” It’s the exact tactic he used with California HSR
- wmf 4mo ago
  I don't see anyone making that argument and we shouldn't allow it. The "temporary" generators are bad enough.

fc417fc802 4mo ago

I think that's looking at it the wrong way. Just view it as a fleet of satellites with computers in them that exist for the purpose of selling capacity. I don't see any issues with the physical fundamentals but the economics in terms of dollars either per flop or per bit transferred is where I don't understand how it's supposed to work. Satellites are really expensive and electricity on the surface is relatively cheap. What hypothetical prospective customers are willing to pay the necessary rates? I understand that bandwidth back to the surface is expensive but are we really expecting so much raw data to be trapped in space that it justifies sending computers into orbit in order to crunch it at the source?

queenkjuul 4mo ago
The physical fundamentals don't work. Radiating exhaust heat is exponentially harder in space than in the atmosphere.
- fc417fc802 4mo ago
  What is the equilibrium temperature of a panel of black sheet metal hanging out at an orbit of 1 AU? Because if the thing is solar powered then it cannot exceed that temperature on average (ie across the entire mass) due to energy being conserved. You can do goofy things like using solar power coupled with a heating element (such as a GPU) to shift more heat to one part of the panel or another (ie employ an insufficient heat spreader design) but you fundamentally cannot exceed the equilibrium temperature on average.
  - queenkjuul 4mo ago
    Well the equilibrium temperature of outer space is roughly 0K. So how do you remove megawatts of heat in 0K?