The real issue with space-based data centers isn’t just whether they’re a “bad idea” from an engineering perspective; it’s that they represent the ultimate transition toward a vertically integrated, unregulated monopoly. While everyone is focused on the technical hurdles, we need to look at who actually benefits from this shift. For someone like Elon Musk, this isn’t just a project—it’s a way to own the entire global internet stack. Because he owns the “truck” (SpaceX) and the “road” (Starlink), he can launch and link these data centers essentially for free. This creates a market that is so tightly locked into one ecosystem that it can never be challenged by a terrestrial competitor.
From a purely operational standpoint, space turns every earthly liability into a superpower. Data centers on the ground are a nightmare of land taxes, massive water consumption for cooling, and constant strain on local power grids. In orbit, those costs vanish. Heat is radiated into the vacuum for free, and solar power is available 24/7 without weather or night cycles getting in the way. Even the physical security is inherently top-notch because the hardware is literally unreachable. When you combine that with a mesh network like Starlink, the need for laying fiber lines disappears entirely. The user just needs an antenna, and the “gatekeeper” handles everything else in the sky.
The terrifying downside is that this creates a jurisdictional black hole. If a server is orbiting 500km above the Earth, whose laws actually apply to the data stored on it? We’re talking about a “gated community” where the ownership, pricing, surveillance policies, and privacy standards are all controlled by a single entity with zero competition or government oversight.
Once we stop building ground infrastructure and rely solely on the “space cloud,” we lose all leverage. It’s an engineering miracle for the person who owns it, but it’s a democratic nightmare for the rest of us. It’s not just a bad idea; it’s the construction of a digital kingdom that sits physically and legally beyond our reach.
When you combine that with a mesh network like Starlink, the need for laying fiber lines disappears entirely
Citation needed.
And on water usage, I will point out that gas generators and evaporative cooling are only used on Earth because other methods (geothermal, big radiators, heatpumps) are somewhat more expensive… Not, like, orders of magnitude more expensive like pure radiative cooling in space.
We already radiate heat away just fine in space, it’s just a matter of how much space do you need to use to do it and all the implications of what that would mean for any given satellite. I wouldn’t call it free, because you need the hardware to do it and the extra weight reduces the payload capacity of whatever you’re sending up, but we can do it.
Starlink also uses laser links to talk to each other which these satellites would also use. How they work can depend, but generally they bounce around in space until they can’t, and they might come back down to land, to move somewhere else over fiber to another ground station until they can go back up to reach you. But the more laser links the less they have to come down for technical reason, but they might still come down for bandwidth reason. I don’t really know how likely it is that any given connection is point to point.
Example of what could happen.
Your dish -> starlink -> starlink -> ground station -> Google -> ground station -> starlink -> ground station -> starlink -> groundstation -> starlink -> starlink -> your dish.
Fiber is still the better option on land if you can get it there, but there are a lot of places it’s never going to get laid, and will never be in the air, or on bodies of water.
Edit: Corrections on the laser links with an example.
I get a circular radiator at least a kilometer wide, assuming the radiator is quite efficient, a rather modest datacenter, and very hot coolant (70C).
…Realistically, the coolant temperature would need to be much lower. See how it’s a power of four in the formula? That means the radiator area gets very large real quick.
I cannot emphasize how expensive a functional 1km+ radiator would be in space. It’s mind bogglingly expensive.
If a space datacenter is in LEO like Starlink, then it’s in Earth’s shadow a lot of the time, and would have to be “part” of the starlink network constantly zooming over the ground. If it’s geosynchronous, then laser communication (or any communication) gets real tricky, and latency is limited by the speed of light. I’m not saying it’s impossible, but reliable high data rates would be an expensive engineering challenge.
For 100kW? I’m not going to try and figure things out from that massive site. A pre made calculator would have been nice if they had one.
edit: It is going to be LEO and likely connected to starlink with the same laser link they use.
Edit: Looking at orbits they might use sun synchronous orbits? It might not be in sun 100% of the time, but they are nearly always in sun.
Edit: I have no way to know if this is right, but a couple AI responses are saying for 100kW it would be ~150-170 square meters with temperatures around 70c
100kW? Nvidia BGX 200 servers are 14kW each, not counting the interconnect, or anything else. According to nuggets I’ve read online, we’re talking 200 megawatts for an Earth-based AI datacenter these days, without something exotic like underclocked Cerebras WSEs (which would be pretty neat, actually…)
I get about 0.46 square kilometers, depending on the coolant temperature, and ultimate efficiency of the system (with how you orient the thing relative to solar panels, how you circulate coolant…)
I have no clue what the construction of such a huge structure would look like, but if it was a simple 0.5 inch aluminum sheet, it would weigh like 15,000 metric tons. Even much thinner, that’s still on the order of “mass of a cargo ship”
Why is that, though?
Well, something like the ISS doesn’t generate much heat, and hypothetical rockets that need big radiators have very hot coolant to dissipate heat quickly. But space data centers are the sinister combination of “tons of waste heat” and “needs a low coolant temperature.”
They aren’t making a datacenter like on earth. They’re putting up a ton of satellites that will each generate about 100kW.
Everyone keeps thinking they’re putting these massive things up there, they are not doing that.
Edit: Oh I missed your tool this time was a real calculator this time, thank you! That says 127 square meters, with black body, 70c and 1 (but no idea if those are good values)
That’s interesting, but what’s the point? If it’s like 2 DGX boxes in each satellite, spaced out, the interconnect between them is going to be very slow, and the individual computational power of each satellite will not be that impressive.
And if you connect them all in one constructed mesh and wire them together, well, you’ve made a 200MW datacenter! The economies remain the same.
If hardware gets more power efficient, well… Then why do you need to go to space anymore?
Ya, the economies of how much total space / material for the global network is similar, although lets say higher due to losses in efficiency in distributing it over so many dishes, but in terms of how big any individual radiator is and how much space each one is going to take, the smaller sizes make it easier to manage. Trying to figure out a 150-200m2solarpanel radiator is a lot easier than trying to figure out a 1km2
The individual power of each satellite having to use a mesh network to train might not be fast enough, maybe they’ll still use land based ones for training, but no single person needs more compute than what a satellite can provide. So from the inference / customer computation side of things, it isn’t a problem.
edit: I meant radiator, not solar panel
edit: looks like blackwells can run sunstained at 88c, so that will help a bit more as well on size, the calculator now says 103m2 instead of 127m^2
Granted I never made it further than freshman level physics in college but doesn’t heat needs a media to radiate away. Otherwise it just stays in place? So there would be nothing to move the heat away from installation? The ISS uses these big radiators the emit the waste heat as infrared light. That seems like a plausible method to exhaust waste heat. But I don’t have any clue if that can scale up to the level of a huge data center compared to the systems on the ISS
Heat is energy as “vibration of molecules”. It spreads to adjacent molecules by conduction, unless we have other interesting things going on. Easy stuff.
Vacuum is the absence of molecules to conduct heat to.
Pardon my potential ignorance, but I’m under the assumption that radiating heat in vacuum is NOT easy. Normally, heat escapes from sources into the surrounding atmosphere, whereas in space, only radiant heat (IR?) can bleed off into vacuum. The conductive heat from, say, a cycling loop of water still needs a radiator that vents into surrounding volume. Without atmosphere, radiators can’t conduct efficiently, right?
Your thoughts were really well written. I’m glad you took the time to explain your viewpoints organically instead of taking an easy way out to avoid having to do it yourself.
How about this for what my post was trying to say…
It’s a good idea to the person who can pull it off. It will be highly profitable and they will monopolize that ecosystem. For the rest of us, if this were ever to become adopted wide spread, it has the potential to make something that normal people can no longer compete with and can’t easily avoid (assuming it is significantly subsidized initially to offset cost and get users to adopt it)
I’m no expert, but I feel like a data center in space is a super niche use case. Bandwidth seems like it would be a major issue. Heat seems like it would as well. And as you said, jurisdiction would be a problem that many businesses wouldn’t necessarily want to contend with.
While the devices are difficult to get to physically, should an adversarial state actor send something up, it’s not like we could stop them from accessing the devices in a way we could if they were within the borders of a country. They’re harder to reach for smaller adversaries, and significantly easier for bigger ones. Not to mention significantly harder for us to repair if something goes wrong.
I’m not saying data centers in space are a bad idea in general, but I am not seeing a huge benefit to them right now.
The real issue with space-based data centers isn’t just whether they’re a “bad idea” from an engineering perspective; it’s that they represent the ultimate transition toward a vertically integrated, unregulated monopoly. While everyone is focused on the technical hurdles, we need to look at who actually benefits from this shift. For someone like Elon Musk, this isn’t just a project—it’s a way to own the entire global internet stack. Because he owns the “truck” (SpaceX) and the “road” (Starlink), he can launch and link these data centers essentially for free. This creates a market that is so tightly locked into one ecosystem that it can never be challenged by a terrestrial competitor.
From a purely operational standpoint, space turns every earthly liability into a superpower. Data centers on the ground are a nightmare of land taxes, massive water consumption for cooling, and constant strain on local power grids. In orbit, those costs vanish. Heat is radiated into the vacuum for free, and solar power is available 24/7 without weather or night cycles getting in the way. Even the physical security is inherently top-notch because the hardware is literally unreachable. When you combine that with a mesh network like Starlink, the need for laying fiber lines disappears entirely. The user just needs an antenna, and the “gatekeeper” handles everything else in the sky.
The terrifying downside is that this creates a jurisdictional black hole. If a server is orbiting 500km above the Earth, whose laws actually apply to the data stored on it? We’re talking about a “gated community” where the ownership, pricing, surveillance policies, and privacy standards are all controlled by a single entity with zero competition or government oversight.
Once we stop building ground infrastructure and rely solely on the “space cloud,” we lose all leverage. It’s an engineering miracle for the person who owns it, but it’s a democratic nightmare for the rest of us. It’s not just a bad idea; it’s the construction of a digital kingdom that sits physically and legally beyond our reach.
Citation needed.
And on water usage, I will point out that gas generators and evaporative cooling are only used on Earth because other methods (geothermal, big radiators, heatpumps) are somewhat more expensive… Not, like, orders of magnitude more expensive like pure radiative cooling in space.
We already radiate heat away just fine in space, it’s just a matter of how much space do you need to use to do it and all the implications of what that would mean for any given satellite. I wouldn’t call it free, because you need the hardware to do it and the extra weight reduces the payload capacity of whatever you’re sending up, but we can do it.
Starlink also uses laser links to talk to each other which these satellites would also use. How they work can depend, but generally they bounce around in space until they can’t, and they might come back down to land, to move somewhere else over fiber to another ground station until they can go back up to reach you. But the more laser links the less they have to come down for technical reason, but they might still come down for bandwidth reason. I don’t really know how likely it is that any given connection is point to point.
Example of what could happen.
Your dish -> starlink -> starlink -> ground station -> Google -> ground station -> starlink -> ground station -> starlink -> groundstation -> starlink -> starlink -> your dish.
Fiber is still the better option on land if you can get it there, but there are a lot of places it’s never going to get laid, and will never be in the air, or on bodies of water.
Edit: Corrections on the laser links with an example.
On radiators, plugging it into this formula:
https://projectrho.com/public_html/rocket/heatrad.php
I get a circular radiator at least a kilometer wide, assuming the radiator is quite efficient, a rather modest datacenter, and very hot coolant (70C).
…Realistically, the coolant temperature would need to be much lower. See how it’s a power of four in the formula? That means the radiator area gets very large real quick.
I cannot emphasize how expensive a functional 1km+ radiator would be in space. It’s mind bogglingly expensive.
If a space datacenter is in LEO like Starlink, then it’s in Earth’s shadow a lot of the time, and would have to be “part” of the starlink network constantly zooming over the ground. If it’s geosynchronous, then laser communication (or any communication) gets real tricky, and latency is limited by the speed of light. I’m not saying it’s impossible, but reliable high data rates would be an expensive engineering challenge.
For 100kW? I’m not going to try and figure things out from that massive site. A pre made calculator would have been nice if they had one.
edit: It is going to be LEO and likely connected to starlink with the same laser link they use.
Edit: Looking at orbits they might use sun synchronous orbits? It might not be in sun 100% of the time, but they are nearly always in sun.
Edit: I have no way to know if this is right, but a couple AI responses are saying for 100kW it would be ~150-170 square meters with temperatures around 70c
100kW? Nvidia BGX 200 servers are 14kW each, not counting the interconnect, or anything else. According to nuggets I’ve read online, we’re talking 200 megawatts for an Earth-based AI datacenter these days, without something exotic like underclocked Cerebras WSEs (which would be pretty neat, actually…)
Plugging 200 megawatts into this:
https://www.calctool.org/quantum-mechanics/stefan-boltzmann-law
I get about 0.46 square kilometers, depending on the coolant temperature, and ultimate efficiency of the system (with how you orient the thing relative to solar panels, how you circulate coolant…)
I have no clue what the construction of such a huge structure would look like, but if it was a simple 0.5 inch aluminum sheet, it would weigh like 15,000 metric tons. Even much thinner, that’s still on the order of “mass of a cargo ship”
Why is that, though?
Well, something like the ISS doesn’t generate much heat, and hypothetical rockets that need big radiators have very hot coolant to dissipate heat quickly. But space data centers are the sinister combination of “tons of waste heat” and “needs a low coolant temperature.”
They aren’t making a datacenter like on earth. They’re putting up a ton of satellites that will each generate about 100kW.
Everyone keeps thinking they’re putting these massive things up there, they are not doing that.
Edit: Oh I missed your tool this time was a real calculator this time, thank you! That says 127 square meters, with black body, 70c and 1 (but no idea if those are good values)
That’s interesting, but what’s the point? If it’s like 2 DGX boxes in each satellite, spaced out, the interconnect between them is going to be very slow, and the individual computational power of each satellite will not be that impressive.
And if you connect them all in one constructed mesh and wire them together, well, you’ve made a 200MW datacenter! The economies remain the same.
If hardware gets more power efficient, well… Then why do you need to go to space anymore?
Ya, the economies of how much total space / material for the global network is similar, although lets say higher due to losses in efficiency in distributing it over so many dishes, but in terms of how big any individual radiator is and how much space each one is going to take, the smaller sizes make it easier to manage. Trying to figure out a 150-200m2
solarpanelradiator is a lot easier than trying to figure out a 1km2The individual power of each satellite having to use a mesh network to train might not be fast enough, maybe they’ll still use land based ones for training, but no single person needs more compute than what a satellite can provide. So from the inference / customer computation side of things, it isn’t a problem.
edit: I meant radiator, not solar panel
edit: looks like blackwells can run sunstained at 88c, so that will help a bit more as well on size, the calculator now says 103m2 instead of 127m^2
Is it though?
Granted I never made it further than freshman level physics in college but doesn’t heat needs a media to radiate away. Otherwise it just stays in place? So there would be nothing to move the heat away from installation? The ISS uses these big radiators the emit the waste heat as infrared light. That seems like a plausible method to exhaust waste heat. But I don’t have any clue if that can scale up to the level of a huge data center compared to the systems on the ISS
Heat is energy as “vibration of molecules”. It spreads to adjacent molecules by conduction, unless we have other interesting things going on. Easy stuff.
Vacuum is the absence of molecules to conduct heat to.
Wait…
Well, it can also radiate away in the form of EM radiation, typically infrared. That takes time though.
Thoughts?
Pardon my potential ignorance, but I’m under the assumption that radiating heat in vacuum is NOT easy. Normally, heat escapes from sources into the surrounding atmosphere, whereas in space, only radiant heat (IR?) can bleed off into vacuum. The conductive heat from, say, a cycling loop of water still needs a radiator that vents into surrounding volume. Without atmosphere, radiators can’t conduct efficiently, right?
Please set me straight if possible.
I’m no expert, but this is my understanding as well.
These are my thoughts https://distantprovince.by/posts/its-rude-to-show-ai-output-to-people/
Your thoughts were really well written. I’m glad you took the time to explain your viewpoints organically instead of taking an easy way out to avoid having to do it yourself.
How about this for what my post was trying to say…
It’s a good idea to the person who can pull it off. It will be highly profitable and they will monopolize that ecosystem. For the rest of us, if this were ever to become adopted wide spread, it has the potential to make something that normal people can no longer compete with and can’t easily avoid (assuming it is significantly subsidized initially to offset cost and get users to adopt it)
I’m no expert, but I feel like a data center in space is a super niche use case. Bandwidth seems like it would be a major issue. Heat seems like it would as well. And as you said, jurisdiction would be a problem that many businesses wouldn’t necessarily want to contend with.
While the devices are difficult to get to physically, should an adversarial state actor send something up, it’s not like we could stop them from accessing the devices in a way we could if they were within the borders of a country. They’re harder to reach for smaller adversaries, and significantly easier for bigger ones. Not to mention significantly harder for us to repair if something goes wrong.
I’m not saying data centers in space are a bad idea in general, but I am not seeing a huge benefit to them right now.