As with a lot of things, it isn't the initial outlay, it's the maintenance costs. Terrestrial datacenters have parts fail and get replaced all the time. The mass analysis given here -- which appears quite good, at first glance -- doesn't including any mass, energy, or thermal system numbers for the infrastructure you would need to have to replace failed components.
As a first cut, this would require:
- an autonomous rendezvous and docking system
- a fully railed robotic system, e.g. some sort of robotic manipulator that can move along rails and reach every card in every server in the system, which usually means a system of relatively stiff rails running throughout the interior of the plant
- CPU, power, comms, and cooling to support the above
- importantly, the ability of the robotic servicing system toto replace itself. In other words, it would need to be at least two fault tolerant -- which usually means dual wound motors, redundant gears, redundant harness, redundant power, comms, and compute. Alternately, two or more independent robotic systems that are capable of not only replacing cards but also of replacing each other.
- regular launches containing replacement hardware
- ongoing ground support staff to deal with failures
The mass analysis also doesn't appear to include the massive number of heat pipes you would need to transfer the heat from the chips to the radiators. For an orbiting datacenter, that would probably be the single biggest mass allocation.
Failure rates tend to follow a bathtub curve, so if you burn-in the hardware before launch, you'd expect low failure rates for a long period and it's quite likely it'd be cheaper to not replace components and just ensure enough redundancy for key systems (power, cooling, networking) that you could just shut down and disable any dead servers, and then replace the whole unit when enough parts have failed.
Side: Thanks for sharing about the "bathtub curve", as TIL and I'm surprised I haven't heard of this before especially as it's related to reliability engineering (as from searching on HN (Algolia) that no HN post about the bathtub curve crossed 9 points).
on one hand, I imagine you'd rack things up so the whole rack/etc moves as one into space, OTOH there's still movement and things "shaking loose" plus the vibration, acceleration of the flight and loss of gravity...
> The company only lost six of the 855 submerged servers versus the eight servers that needed replacement (from the total of 135) on the parallel experiment Microsoft ran on land. It equates to a 0.7% loss in the sea versus 5.9% on land.
6/855 servers over 6 years is nothing. You'd simply re-launch the whole thing in 6 years (with advances in hardware anyways) and you'd call it a day. Just route around the bad servers. Add a bit more redundancy in your scheme. Plan for 10% to fail.
That being said, it's a complete bonkers proposal until they figure out the big problems, like cooling, power, and so on.
My feeling is that, a bit like starlink, you would just deprecate failed hardware, rather than bother with all the moving parts to replace faulty ram.
Does mean your comms and OOB tools need to be better than the average american colo provider but I would hope that would be a given.
And once you remove all the moving parts, you just fill the whole thing with oil rather than air and let heat transfer more smoothly to the radiators.
Not sure this is such a great idea.
Repair robots
Enough air between servers to allow robots to access and replace componentry.
Spare componentry.
An eject/return system.
Heatpipes from every server to the radiators.
Second: you still need radiators to dissipate heat that is in oil somehow.
It just seems funny, I recall when servers started getting more energy dense it was a revelation to many computer folks that safe operating temps in a datacenter should be quite high.
I’d imagine operating in space has lots of revelations in store. It’s a fascinating idea with big potential impact… but I wouldn’t expect this investment to pay out!
I won't say it's a good idea, but it's a fun way to get rid of e-waste (I envision this as a sort of old persons home for parted out supercomptuers)
On Earth we have skeleton crews maintain large datacenters. If the cost of mass to orbit is 100x cheaper, it’s not that absurd to have an on-call rotation of humans to maintain the space datacenter and install parts shipped on space FedEx or whatever we have in the future.
Consider that we've been at the point where layers of monitoring & lockout systems are required to ensure no humans get caught in hot spots, which can surpass 100C, for quite some time now.
It's all contingent on a factor of 100-1000x reduction in launch costs, and a lot of the objections to the idea don't really engage with that concept. That's a cost comparable to air travel (both air freight and passenger travel).
(Especially irritating is the continued assertion that thermal radiation is really hard, and not like something that every satellite already seems to deal with just fine, with a radiator surface much smaller than the solar array.)
It is really fucking hard when you have 40MW of heat being generated that you somehow have to get rid of.
Are there any unique use-cases waiting to be unleashed?
Keep in mind economics is all about allocation of scarce resources with alternative uses.
Also, making something suitable for humans means having lots of empty space where the human can walk around (or float around, rather, since we're talking about space).
I agree that it may be best to avoid needing the space and facilities for a human being in the satellite. Fire and forget. Launch it further into space instead of back to earth for a decommission. People can salvage the materials later.
1. Satellites are mostly run at room temperature. It doesn't have to be that way but it simplifies a lot of things.
2. Every satellite is a delicately balanced system where heat generation and actively radiating surfaces need to be in harmony during the whole mission.
Preventing the vehicle from getting too hot is usually a much bigger problem than preventing it from getting too cold. This might be surprising because laypeople usually associate space with cold. In reality you can always heat if you have energy but cooling is hard if all you have is radiation and you are operating at a fixed and relatively low temperature level.
The bottom line is that running a datacenter in space makes not much sense from a thermal standpoint and there must be other compelling reasons for a decision to do so.
Traditionally in European papers it used to be 18°C, so if Einstein and Schrödinger talk about room temperature it is that.
I've heard in chemistry and stamp collecting they use 25°C but that is heresy.
Even The Expanse, even them! Although they are otherwise so realistic, that I have to say I started doubting myself a bit. I wonder what would really would happen and how fast...
People even complained that Leia did not freeze over (in stead of complaining about her sudden use of the force where previously she did not show any such talents.)
But I think what people/movies don't understand is that there's almost no conductive thermal transfer going on, because there's not much matter to do it. It's all radiation, which is why heat is a much bigger problem, because you can only radiate heat away, you can't conduct it. And whatever you use to radiate heat away can also potentially receive radiation from things like the Sun, making your craft even hotter.
Free cooling?
Doesn't make much sense to me. As the article points out the radiators need to me massive.
Access to solar energy?
Solar is more efficient in space, I'll give them that, but does that really outweigh the whole hassle to put the panels in space in the first place?
Physical isolation and security?
Against manipulation maybe, but not against denial of service. Willfully damaged satellite is something I expect to see in the news in the foreseeable future.
Low latency comms?
Latency is limited by distance and speed of light. Everyone with a satellite internet connections knows that low latency is not a particular strength of it.
Marketing and PR?
That, probably.
EDIT:
Thought of another one:
Environmental impact?
No land use, no thermal stress for rivers on one hand but the huge overhead of a space launch on the other.
Not being physically located the US, the EU, or any other sovereign territory, they could plausably claim exemption from pretty much any national regulations.
A lot of these is a supercomputing Dyson swarm.
Also do chips in space need casing or could the wafers be just exposed on that back layer?
edit: I think the optimal packing could be a simple rolled-up scroll, that unfurls in space into a ribbon. A very lazy design where the ribbon has no orientation control, randomly furls and knots; and only half of it is (randomly) facing the sun at any given time. And the compute units are designed work under those conditions—as they are to be robust against peers randomly disappearing to micrometeorites, to space radiation, and so forth.
Because, you could make up for everything in quantity. A small 3x5 meter cylinder of rolled-up foil stores—at the mm-thickness scale, 10's of gigawatts of compute; at the micron scale, 10's of terawatts. Of course that end is far-future sci-fi stuff!
1. YOLO. Yeet big data into orbit!
2. People will pay big bucks to keep their data all the way up there!
3. Profit!
It could make sense if the entire DC was designed as a completely modular system. Think ISS without the humans. Every module needs to have a guaranteed lifetime, and then needs to be safely yet destructively deorbited after its replacement (shiny new module) docks and mirrors the data.
Doesn't this massively surface area also mean a proportionately large risk of getting damaged by orbital debris?
Cooling is one of the main challenges in designing data centers.
Reliable energy? Possible, but difficult -- need plenty of batteries
Cooling? Very difficult. Where does the heat transfer to?
Latency? Highly variable.
Equipment upgrades and maintenance? Impossible.
Radiation shielding? Not free.
Decommissioning? Potentially dangerous!
Orbital maintenance? Gotta install engines on your datacenter and keep them fueled.
There's no upside, it's only downsides as far as I can tell.
... and then you realize that because it is space, there's almost nothing out there to absorb the heat ...
new vc rule: no investing in space startups unless their founders have 1000 hours in KSP and 500 hours in children of a dead earth
Radiators work great in space. Stefan-Boltzmann's law. The ISS's solar panels are MUCH smaller than the radiators. Considering datacenters on Earth have to have massive heat exchangers as well, I really think the bUt wHaT aBoUt rAdiAtOrs is an overblown gotcha, considering every satellite still has to dump heat and works just fine.
Even here on earth, contemporary GPU racks for AI have had to move to liquid cooling because it is the only way to extract enough heat. At 120 kW for 18x 1U servers (GB200 NVL72), the power density is waaay beyond what you can do with air even.
The last time Starcloud was doing the rounds on HN, I estimated that they need to be pumping water at a flow rate of 60 000 liters per second, if you use the numbers in their whitepaper. That's a tenth of the Sacramento river, flowing in space through a network with a million junctions and hoping nothing leaks.
If YC is hell bent on lighting piles of money on fire, I can think of some more enjoyable ways.
The whitepaper also says that they're targeting use cases that don't require low latency or high availability. In short: AI model training and other big offline tasks.
For maintenance, they plan to have a modular architecture that allows upgrading and/or replacing failed/obsolete servers. If launch costs are low enough to allow for launching a datacenter into space, they'll be low enough to allow for launching replacement modules.
All satellites launched from the US are required to have a decommissioning plan and a debris assessment report. In other words: the government must be satisfied that they won't create orbital debris or create a hazard on the ground. Since these satellites would be very large, they'll almost certainly need thrusters that allow them to avoid potential collisions and deorbit in a controlled manner.
Whether or not their business is viable depends on the future cost of launches and the future cost of batteries. If batteries get really cheap, it will be economically feasible to have an off-the-grid datacenter on the ground. There's not much point in launching a datacenter into space if you can power it on the ground 24/7 with solar + batteries. If cost to orbit per kg plummets and the price of batteries remains high, they'll have a chance. If not, they're sunk.
I think they'll most likely fail, but their business could be very lucrative if they succeed. I wouldn't invest, but I can see why some people would.
This is hiding so, so much complexity behind a simple hand wavy “modular”. I have trained large models on thousands of GPUs, hardware failure happen all the time. Last example in date: an infiniband interface flapping which ultimately had to be physically replaced. What do you do if your DC is in space? Do you just jettison the entire multi million $ DGX pod that contains the faulty 300$ interface before sending a new one? Do you have an army of astronauts + Dragons to do this manually? Do we hope we have achieve super intelligence by then and have robots that can do this for us ?
Waving the “Modular” magic key word doesn’t really cut it for me.
I was implying an unspoken obvious "but why would you?"
But of course the answer I missed was you don't, you make money from people who, for whatever reason, want to drink from shoes.
They will calm down.
Any purported advantages have to contend with the fact that sending the modules costs millions of dollars. Tens to hundred millions
This is true even if your company moves the actual launching to, say, a platform in international waters- you (either a corporation or an individual) are still regulated by your home country, and that country is responsible for your actions and has full enforcement rights over you. There is no area beyond legal control, space is not a magic "free from the government" area.
To escape the law you need to hide or protect something on earth (your ground station(s), downlinks). If you can hide or protect that infrastructure on earth, why bother putting the computers in space?
Unless you go up there with it and a literal lifetime supply? Although I guess if you don't take much it's still a lifetime supply...
Nations come and go. In my lifetime, the world map has changed dozens of times. Incorporate in a country that doesn't look like it's going to be around very long. More than likely, the people running it will be happy to take your money.
This principle was established when Nazis were convicted for war crimes at Nuremburg for violating treaties that their predecessor state the Weimar Republic signed, even after the Nazi's repudiated those treaties and claimed they were signed by an illegitimate state, and that they were a new Reich, not like the Wiemar Republic.
Basically if territory changes hand to an existing state that state will obviously still have obligations, and if a new state is formed, then generally it is assumed to still carry the obligations of the previous state. There is no "one weird trick" to avoid international law. I assure you that the diplomats and lawyers 80 years ago thought of these possibilities. They saw what resulted from the Soviet and Nazi mutual POW slaughters, and set up international law so no one could ignore it.
And more critically - they have successor states.
The Russian Federation is treated as the successor to the USSR in most cases (much to the chagrin of the rest of the CIS) and Serbia is treated as the successor to Yugoslavia (much to the chagrin of the rest)
But if international waters isn't enough (and much cheaper) then I don't think space will either. Man's imagination for legal control knows no bounds.
You wait (maybe not, it's a long wait...), if humankind ever does get out to the stars, the legal claims of the major nations on the universe will have preceded them.
> Servers outside any legal jurisdiction
Others have weighed in on the accuracy of this, with a couple pointing out that the people are still on the ground. There's a thread in _Critical Mass_ by Daniel Suarez that winds up dealing with this issue in a complex set of overlapping ways.
Pretty good stuff, I don't think the book will be as good as the prior book in the series. (I'm only about halfway through.)
Plus you can just have a couple of politicians from each major power park their money on that satellite.
unless everybody is angry at satellite in which case it is a price everybody is even eager to pay.
>Plus you can just have a couple of politicians from each major power park their money on that satellite.
I've long had the idea that there are fashions in corruption and a point at which to be corrupt just becomes too gauche and most politicians go back to being honest.
This explains the highly variant history of extreme corruption in democracies.
At any rate while the idea that the cure for any government interference is to be sufficiently corrupt sounds foolproof in theory I'm not sure it actually works out.
If I was a major politician and you had my competitors park their money on your satellite it would become interesting for me to get rid of it. Indeed if you had me and my competitors on the satellite I might start thinking how do I conceal getting my money out of here and then wait for best moment to ram measure through to blow up satellite.
See: https://unusualwhales.com/politics. Some of these politicians on both sides are very good and consistent stock pickers indeed.
2026, we will get ransomware from space!
The RaaS groups have hundreds of millions of dollars so in theory they actually could get something like that setup if they wanted.
Ahem, cloud ransomware.
But what about when we’re making multi-year journeys to Mars and we need a relay network of “space data centers” talking to each other, caching content, etc?
We may as well get ahead of the problems we’ll face and solve them in a low-stakes environment now, rather than waiting to discover some novel failure scenario when we’re nearing Mars…
How would this work? Planets orbit at different speeds, so you can't build a chain of relays to another planet. I can imagine these things orbiting planets, but is that worth it compared to ground-based systems?
Cooling isn't actually any more difficult than on Earth. You use large radiators and radiate to deep space. The radiators are much smaller than the solar arrays. "Oh but thermos bottles--" thermos bottles use a very low emissivity coating. Space radiators use a high emissivity coating. Literally every satellite manages to deal with heat rejection just fine, and with radiators (if needed) much smaller than the solar arrays.
Latency is potentially an issue if in a high orbit, but in LEO can be very small.
Equipment upgrades and maintenance is impossible? Literally, what is ISS, where this is done all the time?
Radiation shielding isn't free, but it's not necessarily that expensive either.
Orbital maintainence is not a serious problem with low cost launch.
The upside is effectively unlimited energy. No other place can give you terawatts of power. At that scale, this can be cheaper than terrestrially.
Modern solar panels are way more efficient than the ancient ones in ISS, at least 10x. The cooling radiators are smaller than solar panels because they are stacked and therefore effectively 5x efficient.
Unless there are at least 2x performance improvements on the cooling system, the cooling system would have to be larger than solar panels in a modern deployment.
There will probably be a lot more edge computing in the future. 20 years ago engineers scoffed at the idea of deploying code into a dozen regions (If you didn’t have a massive datacenter footprint) but now startups do it casually like it’s no big deal. Space infrastructure will probably have some parallels.
The Chinese project involves a larger number of less powerful inference-only nodes for edge computing, compared to Starcloud's training-capable hyperscale data centers.
[1] Andrew Jones. "China launches first of 2,800 satellites for AI space computing constellation". Spacenews, May 14, 2025. https://spacenews.com/china-launches-first-of-2800-satellite... [2] Ling Xin. "China launches satellites to start building the world’s first supercomputer in orbit". South China Morning Post, May 15, 2025. https://www.scmp.com/news/china/science/article/3310506/chin... [3] Ben Turner. "China is building a constellation of AI supercomputers in space — and just launched the first pieces". June 2, 2025. https://www.livescience.com/technology/computing/china-is-bu...
Are there many startups actually taking real advantage of edge computing? Smaller B2B places don't really need it, larger ones can just spin up per-region clusters.... and then for 2C stuff you're mainly looking at static asset stuff which is just CDNs?
Who's out there using edge computing to good effect?
If starcloud integrated with something like starlink, using the laser inter satellite links to distribute ground comms across a network of satellites, then the datacenter maintaining a direct link to a base station is probably a non-issue for most purposes.
It's outside of any jurisdiction, this is a dream come true for a libertarian oligarch.
For your other concerns, the risks are worth it for customers because of the main reward: No laws or governments in space! Technically, the datacenter company could be found liable but not for traffic, only for take-down refusals. Physical security is the most important security. For a lot of potential clients, simply making sure human access to the device is difficult is worth data-loss,latency and reliability issues.
https://en.wikipedia.org/wiki/Outer_Space_Treaty
> Article VI of the Outer Space Treaty deals with international responsibility, stating that "the activities of non-governmental entities in outer space, including the Moon and other celestial bodies, shall require authorization and continuing supervision by the appropriate State Party to the Treaty" and that States Party shall bear international responsibility for national space activities whether carried out by governmental or non-governmental entities.
This premise is basically false. Most datacenter hardware, once it has completed testing and burn in, will last for years in constant use.
There are definitely failures but they're very low unless something is wrong like bad cooling, vibration, or just a bad batch of hardware.
https://www.backblaze.com/cloud-storage/resources/hard-drive...
Yes it was ONLY 1,000 out of 300,000. But that is only harddrives not other hardware failures/replacement. But it goes to show that things do fail. And the cost of replacement in space is drastically more expensive. The idea of a DC in space as it stands is a nothing burger.
Allowing the failed equipment to sit there can in fact cut costs because it allows you to design the space without consideration of humans needing to be able to access and insert/remove servers.
The higher the cost of bringing someone in to do maintenance, the more likely it is you will just design for redundancy of the core systems (cooling, power, networking), and accept failures and just disable failed equipment.
so you might have problems if you were to do something that causes a lot of vibration, like launch the entire data center into space?
But does work if I rotate phone to landscape mode.
- lots of cheap power - deploy 100s of ASICs, let each of them fail as they go
Paradoxically the datacenter in LEO is cheaper than on the ground, and have bunch of other benefits like for example physical security.
It's a crowded field, you have to do something to stand out!
More realistically, just drop a thermally conductive cable down to low solar orbit. Absolutely unlimited.
A Falcon Heavy launch is already under $100M, and in the $1400/kg range; Starship’s main purpose is to massively reduce launch costs, so $1000/kg is not optimistic at all and would be a failure. Their current target is $250/kg eventually once full reusability is in place.
Still far from the dream of $30/kg but not that far.
The original “white paper” [1] also does acknowledge that a separate launch is needed for the solar panels and radiators at a 1:1 ratio to the server launches, which is ignored here. I think the author leaned in a bit too much on their deep research AI assistant output.