To say the quiet part out loud, I don't think any serious companies have any intention to build a data center in space. There is no benefit in actually trying this. There is however, benefit in saying you'll do it to advance a narrative and distract from the problems terrestrial data centers are facing to an audience that mostly doesn't understand how heat transfer in a vacuum works.
It can be considered as advertising. Like Coca-Cola. Not actually anything new or real most of the time. But keeping the mind-share. Making the company seem like they are on cutting-edge, visionary and futuristic. After all the scam is build on future promises. And not the current day real profits.
Classic misaligned incentives - pretendgineering is far more profitable than building stuff that works reliably and is useful.
We've moved past bullshit jobs to a bullshit economy, which operates by moving money from investors to billionaires and back again, driven by pitch deck thoughts and prayers and implied threats. ("Bail us out or everyone dies.")
I always assume, unfortunately, that once companies start to get to a certain point they become strategic, and military applications comes into play. They then probably get special consideration when it comes to funding and access. All of Musk's efforts certainly fit this paradigm.
The only real advantage is 24/7 power without having to use batteries (or some other power supply at night or when cloudy). The way solar prices are going the problem of suppling power when the sun isn’t visible is a real bottleneck.
For 24/7 solar... you are either in a sun synchronous orbit or in a very high orbit.
The sun synchronous are polar orbits ($$$) that are preferred for earth observation (so that the sun is casting the same shadows). As these are polar orbits, the satellite is not overhead all the time and getting a satellite into such an orbit takes a bit of work.
A SpaceX is at about $3k / kg to LEO. The numbers I see suggest a $20k / kg to a polar orbit.
The next option is being far enough out of the way that the earth's shadow isn't an issue. For that, instead of a 500 km sun synchronous orbit, you'd be going to 36,000 km orbit. This is a lot further from the surface, takes a lot more fuel... and it's a geostationary orbit.
However, as a geostationary orbit, these spots are valuable. Slots in this orbit are divided into slots.
> There are only 1,800 geostationary orbital slots, and as of February 2022, 541 of them were occupied by active satellites. Countries and private companies have already claimed most of the unoccupied slots that offer access to major markets, and the satellites to fill them are currently being assembled or awaiting launch. If, for example, a new spacefaring nation wants to put a weather satellite over a specific spot in the Atlantic Ocean that is already claimed, they would either have to choose a less optimal location for the satellite or buy services from the country occupying the spot they wanted.
> Orbital slots are allocated by an agency of the United Nations called the International Telecommunication Union. Slots are free, but they go to countries on a first-come, first-served basis. When a satellite reaches the end of its 15- to 20-year lifespan, a country can simply replace it and renew its hold on the slot. This effectively allows countries to keep these positions indefinitely. Countries that already have the technology to utilize geostationary orbit have a major advantage over those that do not.
Furthermore, the "out of a nations control" - those slots are owned by nations. Countries would likely be very annoyed for someone to be putting satellites there without authorization. Furthermore, they only work with the countries on those areas. They also require spacing to ensure that you can properly point an antenna to that satellite.
Furthermore, geosynchronous orbits have a 0.5 second round trip lag. This could be a problem for data centers.
Putting things in these orbits is pricy. For LEO, you'd need a lot of them. For geosynchronous, the idea of servicing them is pretty much a "you can't do that" (in 10 - 20 years they use their last fuel and get pushed to a higher orbit and pretty much get forgotten about).
Satellites in geosynchronous orbit are things that need to be especially well behaved because any orbital debris in that area could really ruin everyone's day.
Geosynchronous orbits do not pass through the Earth's shadow as much as you might think. These orbits sit in the same plane as the equator, which is tilted 23.5 degrees when compared to a line from the sun to the earth.
They still pass through the earth's shadow in the weeks around the equinoxes though. Worst case is about 70 minutes of shadow.
That said, it seems more likely to me that there is no requirement to stay over the same spot on the earth, and a lower altitude sun-synchronous orbit would be used.
The real advantage is latency but who really needs that? The military may have some use cases (think remote control of drones and the link between the controllers and satellites) but the use cases are limited
There's one obvious potential application, which is caching of common requests. If something like segments of streams or any CDN contents is cached on the satellite, it reduces communication to a single hop for a large portion of traffic (IIRC, 70% or so?). Storage is very lightweight these days and failure to read cached data is not critical, so putting lots of SSDs on a LEO constellation satellite seems like a no-brainer to me if you're trying to optimize bandwidth usage.
Many of the dumb ideas being hyped in this AI bubble make sense viewed through this lens.
Data centres stirring up opposition? Sell a sci-fi vision that you will move them to Space! And reassure your over-extended investors that the data centre buildout rush you’re committing to isn’t going to get bogged down in protests and lawsuits.
The people hyping this stuff are not stupid, just their real goal (make as much money as possible as quickly as possible) has only a vague relationship to what they claim to be doing.
At the point, it's beginning to feel a bit like the 419 scam (where you make the details deliberately absurd so as to ward off people inclined to be sceptical early, leaving you with only the easiest marks.) SMRs! Data centres in space! "phD level AIs".
I am skeptical as well BUT on the cooling question, which is one of the main concerns we all seem to have, the article is doing a bit of an apples-to-oranges comparison between the ISS and a cluster of small satellites.
It cites the ISS's centralized 16kW cooling system which is for a big space station that needs to collect and shunt heat over a relatively large area. The Suncatcher prototype is puny in comparison: just 4 TPUs and a total power budget of ballpark 2kW.
Suncatcher imagines a large cluster of small satellites separated by optical links, not little datacenter space stations in the sky. They would not be pulling heat from multiple systems tens of meters away like on the ISS, which bodes well for simpler passive cooling systems. And while the combined panel surface area of a large satellite cluster would be substantial, the footprint of any individual satellite, the more important metric, would likely be reasonable.
Personally I am more concerned with the climate impact of launches and the relatively short envisioned mission life of 5 years. If the whole point is better sustainability, you can't just look at the dollar cost of launches that don't internalize the environmental externalities of stuff like polluting the stratosphere.
In theory rocket launches sound bad, with burning fuels all the way up to the top layers of the atmosphere, but it's not clear right away that we're significantly increasing the "burnt up stuff" vs say, the ~100 tons of meteorites that hit every night.
Arguments re: Methane as a non-renewable resource are of course right, except that we technically can synthesize methane from CO2 + electricity (e.g., terraform industries), but the pollution angle is presented as-is, without a systematic analysis, right?
Starlink v2 Mini has about 35 kW of solar power at peak irradiance. 2 kW is quite far from the limit of how much juice we can pack into modern mass produced satellites.
Some of the proposals are much much bigger than this. Five GW, and 16 square kilometres.
It’s amusing that the article points out how large the radiators will have to be, when the proposals already include building giant radiators. Or that the satellites will have to be vastly larger than the ISS; surprise, surprise, that’s also part of the plan.
I mean why not just have a whole bunch of floating buoys doing computation on the ocean? They can probably get energy both from solar and from the tidal wave energy. Cooling certainly won't be an issue.
Related" "A City on Mars" (2024) [1] A useful book on why self-sustaining settlements on Luna, Mars, or earth orbit are pretty much hopeless. Remote bases that take a lot of supply, maybe, with great difficulty. The environment is just too hostile and doesn't have essential resources for self-sustaining settlements.
The authors go into how Antarctic bases work and how Biosphere II didn't.
The worst real estate on Earth is better than the best real estate on Mars or Luna.
I'm as critical as OP on data centers in space, but "A City on Mars" was a really badly researched book, full of errors, that completely misrepresented the would-be Mars settler position. I wouldn't take seriously anyone quoting it unless they've also read, at minimum, "The Case for Mars" as well.
I wasn't terribly impressed with this one. I found it mostly just a bundle of vague negativity and insufficient (disingenuous?) use of problem-solving. However if you want to try it then give the rebuttal a fair shake too.
I was very interested to see in that rebuttal that they explicitly called out ‘datacenters in space’ as a means of ‘exporting’ solar power to the earth.
> As the Weinersmiths point out, the ease of generating solar electricity in space is foundational to space
development. They focus on the challenges in beaming power back to the Earth, but the “power” could
be returned to the Earth in other ways, such as by doing energy intensive manufacturing in space, with
the result that we do not need the power on the Earth itself. One modern idea that O’Neill did not
consider is to move server farms in space, where power is cheap and you can dump heat into space with
a black piece of metal. If this was done on a large scale, the carbon impact of data services on the Earth
would drop greatly even if power is not beamed back to the Earth. There are almost certainly other
ways we can use power in space to do things in space that benefit people on the Earth.
So the original article seems to think that cooling is a significant challenge and that solar power in space is not ‘that much’ more effective than on the earth, and the other that cooling is trivial and that solar power is easily obtained. I’m inclined to go with ‘space is hard’ as that seems to comport with my other readings, but obviously the critique of ‘a city on mars’ is advocating for space exploration and is so motivated to minimize the difficulties.
"One modern idea that O’Neill did not consider is to move server farms in space, where power is cheap and you can dump heat into space with a black piece of metal."
> "One modern idea that O’Neill did not consider is to move server farms in space, where power is cheap and you can dump heat into space with a black piece of metal."
Minor quibble - radiators are white in the visible spectrum.
> The radiators on the ISS are a high-emissivity white paint, meaning that they are dark in the infrared spectrum where the heat is emitted. They are white in the visible spectrum to reflect sunlight.
> The radiators on the shuttle are have a two-layer coating: a silver reflective layer covered by a thin Teflon film. The Teflon layer is opaque to infrared light, so the high emissivity of Teflon dominates. Visible light passes through the Teflon layer and is reflected by the silver layer, so the solar absorbance is low.
One mistake that the article seems to make is to assume that the data center is in one huge satellite.
I think a better model would be a fleet of rack or server level satellites. That significantly reduces the heat and cooling requirements and improves redundancy since losing a single satellite sure to radiation would be less significant. Further, due to economies of scale these satellites could be produced in mass, similar to the starlink satellites of today.
One issue is that these satellites would be to be connected via high bandwidth free space optical links instead of Ethernet, requiring precise formations, but that is currently being tested by multiple companies.
That being said, I don't see this ever being cheaper than terrestrial data centers. I just don't think the idea is as stupid as the article implies - it just requires doing things differently than NASA has done in the past.
Datacenters in space is about circumventing nation states masked as ambitions to generate more power.
Follow the rationale:
1. Nation states ultimately control three key infrastructure pieces required to run data centers (a) land (protected by sovereign armed forces) (b) internet / internet infra (c) electricity. If crypto ever became a legitimate threat, nation states could simply seize any one of or all these three and basically negate any use of crypto.
2. So, if you have data centers that no longer rely on power derived from a nation state, land controller by a nation state or connectivity provided by the nation state's cabling infra, then you can always access your currency and assets.
That’s ridiculous. Space is the least nation-state-dependent place to do computing in existence.
All proposed space computing has an incredibly short orbital lifespan (less than 5y).
Every single space launch capable rocket provider in the world is financially, regulatorily, and militarily joined at the hip to a single government. No launches are taking place without that government’s say-so.
Also, space infrastructure is incredibly vulnerable to attack by nation-states as many others in this thread have pointed out.
Whats less well known is as the Ionsphere heats up the upper atmosphere, it bulges out into space like a tyre sidewall bulge. This has the effect of putting an atmosphere in the path of LEO satellite, which then causes the LEO satellite to fall to earth because they are not designed to travel through an atmosphere.
Joule heating is the most important one which can alter the thermospheric dynamics quite significantly.[1]
This is one of the early tipping points in the background of the game "Eclipse Phase", which I always found interesting:
--- >8 ---
The power of nation states is rooted in control of land and safety, as well as resources, which is an extension of the control of land. But once mining asteroids became economically viable, the connection between land and resources disappeared. Once space habitation in space and secretly developed weapon systems from space became viable, the connection between safety, habitation and land disappeared.
This allowed corporations and new organizations to rise to power large enough to challenge nation states. Those in power did feared to lose their power, which caused the great war which gave rise to the grey mass and destroyed earth.
--- 8< ---
It's a very cool back story, which gives rise to a rogue nanite swarm (the gray mass), which forces an evacuation of earth within days. The only way this was even possible was by uploading human minds onto storage and planting them in robots later on. Naturally, most humans are then forced to work for these corporations. Other humans are still biological and they don't like robots, to say the least.
If a company were to go on its own and build data centers in space only to avoid nation state jurisdiction, they better be prepares to defend that hardware in space.
If a country doesn't like what is happening they can shoot it down, and with no humans onboard or nations claiming jurisdiction there really isn't much to stop them or to answer for.
Putting data centers on ships in international waters would be just as effective at evading government control (i.e. not very) while being orders of magnitude easier and cheaper to build and operate.
Recently the USA blew out some some boats in international waters and came back to finish off the survivors, despite thin evidence and no due process, while maintaining that it was legal. If those data centers on ships ever become declared as a 'threat to national security' then they might get the same treatment.
I think GP's point is that an advanced nation-state could just as easily shoot down an orbiting data center as an oceanic data center and that "international space" offers an equally flimsy defense as "international waters" but a much larger price.
You only need to destroy a few. Then you have a cloud of debris that will take down the rest or at the very least force them to use all their fuel making evasive manoeuvres.
If those ships chose to not fly a flag, they'd even have justification to do so. And if they did choose to fly a flag, then that country would have the responsibility to police them, and is the US complained to that country, that country might just withdraw protection anyway. Data center ships just want to loiter where convenient, they're not cigarette boats flying along at 100mph... no way to evade a navy that wants to blow them out of the water.
Microsoft was talking about submarine data centers powered by tidal forces in the early 2000s.
There have been talks of data centers on Sealand-like nation states.
Geothermal ...
Exotic data center builds will always be hyped. Always be within the realm of feasibility when cost is no object, but probably outside of practicality or need.
Commonwealth Fusion Systems called dibs on next last year by saying they’re gonna have a Dominion (Virginia) commercial site up and running in the early 2030s.
The Outer Space Treaty is very very clear: anything launched into space is the responsibility of the country that launched it. Even if a private company payts for it and operates it, it's still the responsibility of the launching nation. Even if you launch from international waters, your operating company is still registered to a specific country, and the company is made up of citizens of one or more countries, and it is those countries which are responsible for the satellites. Those countries, in fact, have the responsibility to make sure that their citizens follow their laws and regulations. Unless you and your entire team are self-sustaining on that datacenter in outer space (maybe possible a century from now? Maybe not possible ever), you will be hunted down by the proper authorities and held to account for your actions. There is no magic "space is beyond the law" rules; it is just as illegal- and you are just as vulnerable to being arrested- for work done on a datacenter in space as work done on a datacenter on the ground.
Spy satellites maneuver so that no one can tell who launched them, or when. If these satellites can do the same, good luck pinning responsibility on someone on the ground. Hell, with Musk's low orbit network, he could probably even provide connectivity to them in a plausibly-deniable manner.
A data center on an orbit that is only known to the operators makes it difficult to use as a data center in a meaningful way - where do you point your uplink?
Spy satellites are individual craft. Proposals tossed about suggest significant constellates to give sufficient coverage to the land.
Suggestions involving square kilometers of solar power are not exactly things that would be easy to hide.
> Data centers in space. The problem is that data centers take up a ton of space and they need a huge amount of energy. Enter StarCloud. This is the beginning of a future where most new data centers are being built in space. They're starting small, but the goal is to build massive orbital data centers that will make computing more efficient and less of a burden on the limited resources down here on Earth.
These aren't small things. You can't hide it.
> And so we're building with a vision to build extremely large full 40 megawatt data centers. It's about 100 tons. It's what you can fit in one full Starship halo bay.
Bitcoin is a great example of something outside of jursidictions. Now look at how much BTC the FBI has seized. In practice, power is gonna power. The US, Russia or China can take out your data centre unless you play by whatever the rules are. If not physically blow up you need to trade, you need a country for ground operations etc. You need a downlink. Being in space meaning no jurisdiction is plain rediculous.
This is the only "advantage" I can see with space-based datacenters. Crypto will remain a joke but putting devices beyond the reach of ground-based jurisdictions is a libertarian dream. It will probably fail - you still need plenty of ground infrastructure.
Data centers in space is about leading investors to circumvent their brains and jump on the hype train at worst, and developing technology around data center infrastructure at best.
Microsoft did something similar with their submarine data center pilots. This gets more press because AI.
I'm sorry, but this is stupid. It's the same dumb thinking behind Sealand: "we're outside state borders! nobody can touch us!", which was only true as long as nobody cared what they were doing. Once Sealand actually started angering people, the Royal Navy showed up and that was that. "Datacenters in space" wouldn't fare any better: multiple nations have successfully tested anti-satellite weapons.
> Once Sealand actually started angering people, the Royal Navy showed up and that was that.
What did the royal navy do? There is no mention of the UK using force against sealand in either the Wikipedia page or this BBC article about sealand. (Though obviously the royal navy could retake sealand if they wanted)
As someone with a similar background to the writer of this post (I did avionics work for NASA before moving into more “traditional” software engineering), this post does a great job at summing up my thoughts on why space-based data centers won’t work. The SEU issues were my first though followed by the thermal concerns, and both are addressed here fantastically.
On the SEU issue I’ll add in that even in LEO you can still get SEUs - the ISS is in LEO and gets SEUs on occasion. There’s also the South Atlantic Anomaly where spacecraft in LEO see a higher number of SEUs.
> On the SEU issue I’ll add in that even in LEO you can still get SEUs
As a sibling post noted, SEUs are possible all the way down to sea level. The recent Airbus mass intervention was essentially a fix for a badly handled SEU in a corner case.
Single event upsets are already commonplace at sea level well below data center scale.
The section of the article that talks about them isn’t great. At least for FPGAs, the state of the art is to run 2-3 copies of the logic, and detect output discrepancies before they can create side effects.
I guess you could build a GPU that way, but it’d have 1/3 the parallelism as a normal one for the same die size and power budget. The article says it’d be a 2-3 order of magnitude loss.
It strikes me that neutral network inference loads are probably pretty resilient to these kinds of problems (as we see the bits per activation steadily decreasing), and where they aren't, you can add them as augmentations at training time and they will essentially act as regularization.
The only advantage I can come up with is the background temperature being much colder than Earth surface. If you ignored the capex cost to get this launched and running in orbit, could the cooling cost be smaller? Maybe that's the gimmick being used to sell the idea. "Yes it costs more upfront but then the 40% cooling bill goes away... breakeven in X years"
Strictly speaking, the thermosphere is actually much warmer than the atmosphere we experience--on the order of 100's or even a 1000 degrees Celsius, if you're measuring by temperature (the average kinetic energy of molecules). However, since particle density is so low, the number of molecules is quite low, and so total heat content of the thermosphere is low. But since particle count is low, conduction and convection are essentially nonexistent, which means cooling needs to rely entirely on radiation, which is much less efficient than other modes at cooling.
In other words, a) background temperature (to the extent it's even meaningful) is much warmer than Earth's surface and b) cooling is much, much more difficult than on Earth.
Technically radiation cooling is 100% efficient. And remarkably effective, you can cool an inert object to the temperature of the CMBR (4K) without doing anything at all. However it is rather slow and works best if there's no nearby planets or stars.
Fun fact though, make your radiator hotter and you can dump just as much if not more energy then you would typically via convective cooling. At 1400C (just below the melting point of steel) you can shed 450kW of heat per square meter, all you need is a really fancy heat pump!
I dont have firm numbers for you since it would depend on environmental conditions. As an educated guess though, I would say a fucking shit ton. You wouldn't want to be anywhere near the damn thing.
A car's "radiator" doesn't actually lose heat by radiation though. It conducts heat to the air rushing through it. That's absolutely nothing like a radiator in a vacuum.
Is it an advantage though ? One of the main objections in the article is exactly that.
There's no atmosphere that helps with heat loss through convection, there's nowhere to shed heat through conduction, all you have is radiation. It is a serious engineering challenge for spacecrafts to getting rid of the little heat they generate, and avoid being overheated by the sun.
A typical CPU heatsink dissipates 10-30% of heat through radiation, and the rest through convection. In space you're in a vacuum so you can't disipated heat through convection.
You need to rework your physical equipment quite substantially to make up for the fact you can't shed 70-90% of the heat in the same manner as you can down here on Earth
Pardon, but the question of "could the operational cost be smaller in space" is almost not touched at all in the article. The article mostly argues that designing thermal management systems for space applications is hard, and that the radiators required would be big, which speaks to the upfront investment cost, not ongoing opex.
Ok, sure, technically. To be fair you can't really assess the opex of technology that doesn't exist yet, but I find it hard to believe that operating brand new, huge machines that have to move fluid around (and not nice fluids either) will ever be less than it is on the surface. Better hope you never get a coolant leak. Heck, it might even be that opex=0 still isn't enough to offset the "capex". Space is already hard when you're not trying to launch record-breaking structures.
Even optimistically, capex goes up by a lot to reduce opex, which means you need a really really long breakeven time, which means a long time where nothing breaks. How many months of reduced electricity costs is wiped out if you have to send a tech to orbit?
Oh, and don't forget the radiation slowly destroying all your transistors. Does that count as opex? Can you break even before your customers start complaining about corruption?
Maintenance will be impossible or at least prohibitively expensive. Which means your only opex is ground support. But it also means your capex depreciates over whatever lifetime these things will have with zero repairs or preventive maintenance.
But ground support will not be cheap. You need to transfer a huge amount of data, which means you need to run and maintain a network of ground stations. And satellite operations are not as cheap as people like to think either.
But the cooling cost wouldn’t be smaller. There’s no good way to eliminate the waste heat into space. It’s actually far far harder to radiate the waste heat into space directly than it would be to get rid of it on Earth.
I don't know about that. Look at where the power goes in a typical data center, for a 10MW DC you might spend 2MW just to blow air around. A radiating cooler in space would almost eliminate that. The problem is the initial investment is probably impractical.
>99.999% of the power put into compute turns into heat, so you're going to need to reject 8 MW of power into space with pure radiation. The ISS EATCS radiators reject 0.07 MW of power in 85 sq. m, so you're talking about 9700 sq. m of radiators, or bigger than a football field/pitch.
Things on earth also have access to that coldness for about half of each day. How many data centers use radiative cooling into the night sky to supplement their regular cooling? The fact that the answer is “zero” should tell you all you need to know about how useful this is.
Look up Tech Ingredients episode on Radiative Paint.
The fact that people aren’t using something isn’t evidence that it’s not possible or even a great idea, it could be that a practical application didn’t exist before or someone enterprising enough hasn’t come along yet.
The atmosphere is in the way even at night, and re-radiates the energy. The effective background temperature is the temperature of the air, not to mention it would only work at night. I think there would need to be like 50-ish acres of radiators for a 50MW datacenter to radiate from 60 to 30C. This would be a lot smaller in space due to bigger temp delta. Either way opex would be much much less than average Earth DC (PUE almost 1 instead of run-of-the mill 1.5 or as low as 1.1 for hyperscalers). But yeah the upfront cost would be immense.
I think you’re ignoring a huge factor in how radiative cooling actually works. I thought the initial question was fine if you hadn’t read the article but understand the downvotes due to doubling down. Think of it this way. Why do thermoses have a vacuum sealed chamber between two walls in order to insulate the contents of the bottle? Because a vacuum is a fucking terrible heat convector. Putting your data center into space in order to cool it is like putting a computer inside of a thermos to cool it. It makes zero fucking sense. There is nowhere for the heat to actually radiate to so it stays inside.
I think by far the most mass in this kind of setup would go into the heat management, which could probably last a long time and could be amortized separately from the electronics.
How would the radiators be useful if the electronics no longer are? Unless you can repurpose the radiators once the electronics are useless, which you can't in space, then the radiators' useful lifetime is hard limited by the electronics' lifetime.
There are lots of reasons why keeping data centers on the ground might be cheaper but the article seems to be skipping over a few things.
1) ISS is about 30 years old. It's hardly the state of the art in solar technology. Also, it's much easier to get light to solar panels far a larger part of the time. Permanently in some orbits. And of course there is 0% chance of clouds or other obstructions.
2) We'll have Starship soon and New Glenn. Launching a lot of mass to orbit is a lot cheaper than launching the Space Station was.
3) The article complains about lack of bandwidth. Star Link serves millions of customers with high speed, low latency internet via thousands of satellites.
4) There have been plans for large scale solar panels in space for the purpose of beaming energy down in some form. This is not as much science fiction as it used to be anymore.
5) Learning effects are a thing. Based on thirty years ago, this is a bad idea. Based on today, it's still not great. But if things continue to improve, some things become doable. Star link works today and in terms of investment it's not a lot worse than a lot of the terrestrial communication networks it replaces. The notion would have been ridiculous a few decades ago but it no longer is.
In short, counter arguments to articles like this almost write themselves.
Solar panel performance is not the limiting factor in space. Thermal management is. Better solar panels don't help you here. Neither does permanent sunshine -- without the capability to radiate more heat at night, you've made the thermal management problem immensely worse.
Rockets: Launching no mass to orbit is even cheaper still.
Bandwidth: You do realize that even starlink speeds are crazy slow and high latency compared to data center optical connections? Fiber and copper always win out over wifi. With space, you are stuck with wifi. (Oversimplified, but accurate.)
Space solar power: there has been talk of this for half a century, yes. It never materialized because, like space data centers, it doesn't make economic sense.
1) ISS is about 30 years old. It's hardly the state of the art in solar technology.
Domestic solar panels are heavy, and dont need to deal with hypersonic sand blasting. even at that height, you are in shadow every 90 minutes.
> 3) The article complains about lack of bandwidth. Star Link serves millions of customers with high speed, low latency internet via thousands of satellites.
Right. First power and heat are a massive pain to deal with. You need megawatts to run a datacentre. A full rack of GPUs (48u, 96 GPUs) is around 40-70kw. It also weighs a literal ton.
You also need to be able to power that in the time when you are in darkness. BUT! when you are zooming around the earth every 90 minutes, you can't maintain a low latency connection, because the distance between you and the datacentre.
That means geostationary, as that solves most of your power issues, but now you have latency and bandwidth issues. (oh and power, inverse square law and bandwidth are related)
> Special cases of the Sun-synchronous orbit are the noon/midnight orbit, where the local mean solar time of passage for equatorial latitudes is around noon or midnight, and the dawn/dusk orbit, where the local mean solar time of passage for equatorial latitudes is around sunrise or sunset, so that the satellite rides the terminator between day and night.
The dawn dusk orbit is in constant sunlight. The noon-midnight orbit isn't.
Those orbits (and their corresponding constellations) lack 100% availability for a ground station.
Furthermore, a polar orbit launch is quite a bit more expensive since it requires a significant change in inclination.
It’s not about things improving. This isn’t a great idea that’s not yet feasible, the way ubiquitous satellite communication was. This is a fundamentally bad idea based on the physics, not the technology.
Satellites are so much more expensive than just running a wire, so why is satellite communication desirable? Because one satellite can serve many remote places for less than it costs to run a wire to all of them, it can serve the middle of the ocean, it can serve moving vehicles. These are fundamental advantages that make it worthwhile to figure out how to make satellite communication viable.
Data centers in space offer no fundamental advantages. They have some minor advantages. Solar power is somewhat more available. They can reach a larger area of ground with radio or laser communication. And that’s about it. Stack those advantages against the massive disadvantages in cooling, construction, and maintenance. Absent breakthroughs in physics that allow antigravity tech or something like that, these advantages are fundamental, not merely from insufficient technology.
It is not a good idea listening to experts tell you what can't be done. Science and technology progresses one funeral at at time. Einstein's ideas were crazy for classical scientists and Heisenberg's for Einstein.
The most important thing is making space access ten to one hundred times cheaper with reusable rockets. Then a lot of the problems in the article will not be problems at all.
E.g ISS was designed and created when access to space was extremely expensive. Solar technology and batteries was extremely bad but also super expensive.
You can not use convention but radiation works incredibly well and you can also use the thermal technology of mobile devices.
The most important thing being cheap is that access to the Space become possible for way more people with creativity. Not just a few people with academic titles but people with practical engineering and scientific mastery (that certainly run circles around them on real projects).
There are so many opportunities to use creativity in space, with possibilities that do not exist on earth. For example you can spin or rotate things super fast and so you could have convention inside the machines that rotate.
Interesting point actually. yeah, when spacex was trying to build a reusable rockets, many traditional rocket scientists said that even if you are able to recover stages of the rocket, you still need to refurbish and test a great number of parts, and it just isn’t this panacea for lowering rocket costs (for example, the space shuttle, which was reusable spacecraft, but was super expensive to launch).
When spacex finally got falcon 9 reusability working (and am no expert in this) but from what I read, the pundits were partially right and partially wrong. Yes, refurbishment and testing on the Falcon 9 does cost a lot, but it still brings down the cost significantly (just looked it up, their saying nowadays, the cost savings is something like 70%, which actually is huge). And as importantly, you don’t have to build a new rocket for every launch, and once you get your refurbishment process down like clockwork, you can relaunch them quite often.
So maybe data centers in space won’t be like ones on earth, but they still might be very useful… One idea is that they could become true “space” data centers, that supply powerful computing for satellites near by. This way satellites could get access to much more powerful computing, while still being small themselves (but again, am no expert in this, so maybe this idea also has many holes, for example why not just offload processing to ground based data centers).
Science is very very very rarely disrupted by a small group of visionaries in the same way business or technology are.
Substitute “perpetual motion machines” for “datacenters in space”. For very Heisenberg and Einstein there are thousands of crackpots who wasted huge amounts of (often other people’s) money trying to build perpetual motion machines. None of them were remembered.
The overwhelming majority of real scientific advancement is slow, grinding, difficult, incremental, and group-based.
Substitute “perpetual motion machines” for “datacenters in space”.
This is an absurd strawman. A datacenter in space doesn't violate any fundamental physical laws. Science would not be "disrupted" if engineers made it economically feasible for certain use-cases.
It's totally reasonable to doubt that e.g. >1% of Vera Rubins are going to wind up deployed in space, but fundamentally this is a discussion about large profitable companies investing in (one possible) future of business and technology, not a small group of crackpot visionaries intending to upend physics.
Starlink sounded fairly nuts when it was first proposed, but now there's thousands of routers in space.
I think it's a great article that should discourage a lot of people to waste resources.
To really do it you have to treat this article as a to-do list of challenges to overcome. If you have no ideas on how to address those challenges you should not start.
The idea that science progresses by lone wolf geniuses disrupting the status quo is simply false. It makes a good story for low budget documentaries, but it is basically never true.
What are the fundamental advantages of space-based data centers over terrestrial ones? Certainly not cooling or radiation shielding. Those are almost free on Earth. A Zero-G environment could have some benefits regarding the total size of the construction, but of course being in Earth orbit means Zero-G but does not mean no gravity. Anything in LEO will require constant station-keeping maneuvers, and the more massive the data centers, the more fuel required. Power generation could theoretically be better, but even if you had a 100% efficient PV solar shield, you still need to radiate away the same amount of energy at a rate at least equal to that to maintain thermal equilibrium.
You could say this is all just a question of materials science, and maybe it is, but it’s not anything that makes any sense at all today, nor is it something I think anyone should expect to be up and running in the next century.
> The most important thing being cheap is that access to the Space become possible for way more people with creativity. Not just a few people with academic titles but people with practical engineering and scientific mastery (that certainly run circles around them on real projects).
Agreed! Real estate is incredibly cheap in space until Saudi money and private equity figure out a way to make it a scarce resource. Also, we can build massive single suburban homes in space! No need to build vertical and public transit. Just give everyone a rocketship to travel to the nearest space McDs drive through!
I always believed thermal conductivity to be one of the hardest problems in space.
Today the way we diffuse temperature is via the air itself, and without air to carry heat away from components we don’t really have very much to work with.
I know space is cold, but diffusing the cold onto the warm is an ongoing problem as far as I understood it.
Which is why for example of nuclear submarines would not bode well in space, the internal temperature would just continue to rise until eventually the thing will become an oven floating through the solar system.
Even diffusion into air is too slow for some use cases. The whole complaint of datacentres "consuming" water is due to heating it and dumping it back or evaporating it for cooling. This is done because mass air cooling is much less efficient and requires lots of energy to run the fans to force the air through the heat exchangers, which is also extremely loud. And that is, in turn, much more effective than passive radiation, even if you have a ~3K background.
The ISS ammonia-based active heat rejection system is Two units, each 13x3 metres in size and each unit can radiate 35kW.
So to radiate a "mere" 1MW, you need a quarter-acre of radiator. A square km per GW.
The engineering is obviously more than tricky because you have lots of plumbing, gigantic flat structures, and you can't have the radiators facing each other or the sun. Moreover, unlike the ISS, if you want to run the system at full whack the whole time on solar power, it's never in shadow. Which you presumably do want, as that's the putative point of the whole thing. You also can't be sending up service missions without the cost exploding even further, so hopefully you can design everything to last the 5 years despite each handful of fully loaded GPU racks requiring a structure somewhere around the size of the ISS, humankind's crowning glory of high technology, to support.
The comment you were replying to mentioned this. Yes you cant remove heat via convection, but you can use radiators to emit heat as radiation into space.
There are 8,000+ Starlink satellites in orbit right now. Each one has about 30 square-meters of solar panels. That's 240,000 square meters. ISS has 25,000 square meters, so SpaceX has already launched almost 10-times the solar panels of ISS.
The next generation Starlink (V3) will have 250 square meters of solar panels per satellite, and they are planning on launching about 10,000 of them, so now you're at 2.5 million m^2 of panels or 100 times ISS.
All those satellites have their own radiators to manage heat. True, they lose some heat by beaming it to the ground, but data center satellites would just need proportionally larger radiators.
And, of course, all those satellite have CPUs and memory chips; they are already hardened to resist space radiation (or else they wouldn't function).
Almost every single objection to data centers in space has already been overcome at a smaller scale with Starlink. The only one that might apply is cost: if it's cheaper to build data centers on Earth, then space doesn't make sense (and it won't happen). But prices are always coming down in space, and prices on Earth keep going up (because of environmental restrictions).
> The only one that might apply is cost: if it's cheaper to build data centers on Earth, then space doesn't make sense (and it won't happen).
So the only problem left to be solved is that space datacenters would be millions of times more expensive per unit of compute than a ground based datacenter. And cost millions of times more to maintain.
Starlink cost maybe $10 billion. A 100,000 gpu data center costs between $20 and $40 billion to build.
Also remember that data centers last for about 5 years; after that the gpus are obsolete. That’s no different than the lifetime of a Starlink satellite.
Starlink solar panels generate at best 200 W/sqm on average. Even with 2.5 million square metres, that is a total of half a gigawatt. And the cost is not to be ignored! Most of the cost of these data centres is in the GPUs themselves, so you need to add that to the cost of building out the constellation. Unless you are arguing that the cost of supporting infrastructure (cooling, power, etc) costs $10bn to support half a gigawatt of GPUs in the typical data centre, then your numbers are simply way off.
> Starlink is already a small data center! It has power, radiators, and compute!
It is not. This is like saying your phone is already a small data centre. While technically true, we're not talking about the same scale here. StarLink's compute power is a tiny fraction of a modern data centre GPU/TPU. Most of the power budget goes into communication (i.e. its purpose!).
The facts you quoted just made me even more convinced that space-based datacenters will not be cost effective any time soon. If an entire generation of satellites costing many billions of dollars can't power more GPUs than a single terrestrial datacenter, how could it possibly be cost effective?
I think it's important to be distinct here... These "Space DC" companies are not showing up on some Techy-Shark-Tank (or walking into VC meetings) with a promise to investors that they have an established strategy which will pay off.
IMO, they are just answering the question: "If we pour 100B into R&D, could it have a reasonable chance at succeeding?".
For Nvidia (or these other massive companies) the investment is chump change.
Always remember the magic words: dual use technology. The people pushing these aren't saying to you that they want to build data centers in space because conventional data centers are at huge risk of getting bombed by foreign nations or eventually getting smashed by angry mobs. But you can bet they're saying that to the people with the dual-use technology money bag. Or even better, let them draw that conclusion themselves, to make them think it was their idea - that also has the advantage of deniability when it turns out data centers in space was a terrible solution to the problem.
It is far easier to build them at remote places and bunkers (or both). Even at the middle of the ocean will make more sense and provide better cooling (See Microsoft attempt at that).
The only vaguely valid dual use technology I can see coming out of this is improving space-rated processing enough that deep space probes sent out to Uranus or whatever can run with more processing power than a Ti-82 and thus can actually do some data processing rather than clogging up the deep space network for three weeks on an uplink with less power than a lightbulb
At this point I wouldn't be surprised if a non zero number of pitch meetings start with, "in order to not disrupt your life too much as the mobs of the starving and displaced beat down your door"
Nah, they are pretty similar in difficulty for interception - the first US ASAT program used essentially the same Nike Zeus missiles used for ABM duty during the late 50s
not really. Suborbital vehicles achieve orbital heights. It's actually probably easier since you don't need a payload. The velocity alone will do the trick.
In addition to the ludicrous unworkable physics, as it turns out, datacenters need people servicing things all the time. Even if you could get those measly three racks into space, they'd function about a month before some harddisks were failing, network switches were down, some crap breaks in the cooling system, power system short, breakers trip, etc, and on and on.
So obviously we're not going to be some SREs into space to babysit the machines. Have everything fail in place? Have robots do it? What about the regular supply missions to keep replacing all the failing hardware (there's only so many spare HDDs you can have on hand).
> So obviously we're not going to be some SREs into space to babysit the machines.
Shut up! This is the chance for one of us to go into space! I don't care if all I'm doing is swapping 1U pizza boxes in the cold hard vacuum of space, I'm down!
Plus, in space, their electronic components would experience much more radiation (and the effects on components). They could build with rad-hardened components but those are both more expensive and several generations older than SOTA found in the habitable zone.
So many ideas involving AI just seems to be built off of sci-fi (not in a good way), including this one. Like sci-fi, there are little practical considerations made.
Sci-fi isn't even really about the tech. It's about what happens to us, humans, when the tech changes in dramatic ways. Sci-fi authors dream up types of technology that create new social orders, factions, rifts, types of interpersonal relationships, types of fascism, where the unforseen consequences of human ingenuity hoist us upon our collective petard.
But these baffoons only see the blinky shiney and completely miss the point of the stories. They have a child's view of SF the way that men in their teens and 20d thought they were supposed to be like Tyler Durden.
This is a good point and is why I prefer to refer to the genre as Speculative Fiction - not only is it broader but it better gets at the idea behind this type of fiction. Not just space lasers.
> The RAD5545 processor employs four RAD5500 cores, achieving performance characteristics of up to 5.6 giga-operations per second (GOPS) and over 3.7 GFLOPS. Power consumption is 20 watts with all peripherals operating.
That's kind of neat... but not exactly data center performance.
Back to the older RAD750...
> The RAD750 system has a price that is comparable to the RAD6000, the latter of which as of 2002 was listed at US$200,000 (equivalent to $349,639 in 2024).
That isn't exactly price performance. Well, unless you're constrained by "it costs millions to replace it."
So... I'm not really sure what devices they'd be putting up there.
The "data centers in space" is much more a "space launch is a hot technology, AI and data centers are a hot technology... put the two together and its too the moon!" (Or at least that's what we tell the investors before we try to spend all their money)
I think the last time they put commodity hardware in orbit was via the HPE[1] project and the results were quite mixed with failure rates for components that were quite high. In addition to running the system in a twin config to get any meaningful work done.
Best case scenario custom ASICs for specialised workloads either for edge computing of orbital workloads or military stuff.That would be with ability to replace/upgrade components rather than a sealed sat like environment.
Its similar to the hype for spacelink type sats for internet connectivity rather than a proper fiber buildout that would solve most of the issues at less cost.After the last couple of years seeing the deployment in UKR,Sahel its mostly a mil tool.
>The first reason for doing this that seems to come up is abundant access to power in space. This really isn't the case. You basically have two options: solar and nuclear.
I guess that rules our any funding from US govt or Saudi money. Unless someone figures out a way to use fossil fuels to run the data centers! It has to be private equity or a new data center coin offering. Offered to the public and take away the pain and suffering of carrying their current paper currency. We need a new messiah (SBF + Musk + WeWork guy) to craft this narrative.
If you think about it, all the existing data centers are in space already. They're just attached to a big ball of rock, water, and air that acts as a support system for them, simplifying cooling and radiation protection.
If humans are going to expand beyond the Earth, we'll certainly need to get much better at building and maintaining things in space, but we don't need to put data centers in space just to support people stuck on the ground.
It’s not about putting data centers into orbit. It’s about the cost-yield inversion to data centers cooling infrastructure that happens at terawatt scale. All things being equal - a chilled circuit performs better and produces less heat than a hot one. There is a high up front cost to pre-cooling but if you can get in the -60C range, and stay there, you can increase performance and cut energy costs.
When they say data centers in space - they mean data centers you can’t get to because they are flooded with ultra cold dielectric fluid and it costs tens of millions of dollars to bring them back up to human temperatures.
Right now it’s not worth the hassle. At terawatt scale it’s almost mandatory.
When you walk down that line it’s pretty close to putting them in space. No access. Super cold. No air. Tiny, insulated capsule. Thermal management hell. They’ll be buried in mines though, not launched into orbit.
It’s just corporate propaganda to simplify an otherwise insane situation.
You literally just need to be in space, because no typical laws apply if you are there. That little detail outweights all sorts of costs.
So, yeah. There will be datacenters in space. Probably unlike any on the ground. Smaller, very likely not running typical datacenter stuff, weirder, operating on a different set of regulations.
If we're lucky, it will be like Antarctica (research focused, still disputed but not armed, probably not lots of shady stuff happening there, costly but still pays off to be there).
>You literally just need to be in space, because no typical laws apply if you are there.
That makes no sense. Unless you are going to use the data in space (what for?), you need to import it into a country, and it is at that point the crime will have been committed. You can't, for example, circumvent GDPR laws just by sending the data into space first.
This makes no sense. The company will still be on the ground in some country and it has to connect to the Earth internet on the ground in some country. Unless you are talking about actual space pirate station, but in that case it better come equipped with missile defense because it will be attacked sooo fast.
> The company will still be on the ground in some country
But the data won't. That is literally how people launder money. They live in one country and keep their money in another with laxed laws and enforcement. Those people get away a lot.
> it has to connect to the Earth internet
Why? This is only true if the datacenter is directly serving people. As I mentioned previously, I don't believe space datacenters will be serving React apps or anything like that. Those will be weird, non-typical servers.
Want some zero internet use cases?
- Training a cyber-ops LLM without poking eyes and reduced risk of leaks.
- Illegal data-heavy research (bio, weaponry).
- Storing data for surveillance satellites.
All of those can use private links, can be built by private companies under classified contracts, and you would not dare attack an NRO-launched satellite.
There are wayyyy easier ways to just get some private calculations. You can spin up an encrypted memory VM or wire up an eager physical kill switch. Launching satellites would bring a lot of attention and requires skills, money, multiple people with access. But I can do the former just fine by myself.
Really the only potential upside to this, and it's a niche one, is for time or security sensitive compute tasks where the raw data originates in orbit. Every happens over inter satellite link and there's no downlink to Earth until the end of the process (downlink is still a problem as Earth is mostly ocean and wilderness)
E.g. one satellite's wide area sensor payload is processed and "potential wildfire detected". The result is passed to another satellite with finer grained sensing capabilities which is due to pass over in the next X minutes which then tees up a capture.
> roughly 200 GPUs. This sounds like a lot, but lets keep some perspective: OpenAI's upcoming Norway datacenter is intending to house 100,000 GPUs, probably each more power hungry than the H200
So.. 500 reusable rocket travels in space to match an on-ground datacenter? If this is the central argument then it doesn't hold.
Don't get me wrong. I too think whole idea is so outlandish it's likely to never happen, but mostly because the complexity of the whole project is too high.
Google’s paper [1] does talk about radiation hardening and thermal management. Maybe their ideas are naive and it’s a bad paper? I’m not an expert so I couldn’t tell from a brief skim.
It does sound to me like other concepts that Google has explored and shelved, like building data centers out of shipping container sized units and building data centers underwater.
The only sentence in the whole "paper" about cooling is
> Cooling would be achieved through a thermal system of heat pipes and radiators while operating at nominal temperatures
Which is kind of similar to writing a paper about building a bridge over the Pacific and saying "The bridge would be strong enough by being built out of steel". Like you can say it, but that doesn't magically make it true.
It didn't work, it was an utterly terrible idea and they are almost certainly lying about the sentiment that it "worked". No ability to perform maintenance is a complete nonstarter. Communications and power is a nightmare to get right. The thermal management story sucks - just because you have metal touching water doesn't mean you have effective radiation of heat. Actually scaling it up is nearly impossible because you need thicker and more expensive vessels the bigger it gets. The problems go on and on.
> Among the components crated up and sent to Redmond are a handful of failed servers and related cables. The researchers think this hardware will help them understand why the servers in the underwater datacenter are eight times more reliable than those on land.
> “We are like, ‘Hey this looks really good,’” Fowers said. “We have to figure out what exactly gives us this benefit.”
> The team hypothesizes that the atmosphere of nitrogen, which is less corrosive than oxygen, and the absence of people to bump and jostle components, are the primary reasons for the difference. If the analysis proves this correct, the team may be able to translate the findings to land datacenters.
> “Our failure rate in the water is one-eighth of what we see on land,” Cutler said. “I have an economic model that says if I lose so many servers per unit of time, I’m at least at parity with land,” he added. “We are considerably better than that.”
I don't think MS ever revealed enough information to answer that. For example, I haven't seen any explanation of how heat is transferred from the servers to the skin of the container. I can guess how they did it but I don't want to make any judgement based on guesses.
Related (posted just 2hours before this article) : https://news.ycombinator.com/item?id=46086833
"Blimps lifting quantum data centers to the stratosphere? (newatlas.com)"
"... blimps, to lift quantum computers to the stratosphere. There, at an altitude of about 20 km (12.4 miles), temperatures are in the -50 °C range (about -58 °F) and would be cold enough to allow the qubits to function correctly."
Not a space geek but would have guessed at all these things. Feels like common sense. How is anything easier in space? None of it makes sense to me either.
The only thing I could think of is maybe 24h sunlight if far enough away from earth.
Maybe is anothet bubble to grab investor money. A bored ape larping as science.
Only legit thing I can see this being used for is redundant archival storage or just general research into hardening equipment to radiation or micrograv (eg for liquid cooling). But anything that generates significant amounts of heat seems like it'd be a huge problem.
Then again there's lots of space in space, perhaps it's possible to isolate racks/aisles into their own individual satellites, each with massive radiant heatshedding panels? It's an interesting problem space that would be very interesting to try to solve, but ultimately I agree with OP when we come back around to "But, why?" Research for the sake of research is a valid answer, but "For prod"? I don't see it.
Orbital data centers are very hard but this isn't a good explanation of why. There really is more light in space since certain orbits are always in daylight. Radiators are no larger than the solar panels so if you can build multi square kilometer solar arrays you can probably also build massive radiators.
So if the big idea is to have a data center outside of legal jurisdictions why not build a floating data center in the Southern Pacific Ocean? You can power it with floating solar panels provide data via Starlink or a regular communication satellite and still be outside of the law. You might say that it will be vulnerable to pirates, but practically speaking nobody is going down there. Sure you will have to deal with weather, but overall the problems are way easier to solve than building an orbital data center.
But the real reason they won't work is because they're investor scams that were never serious in the first place.
It probably shouldn't be so hard to find military application for more compute in space. Especially give the global surveillance and communication networks like starlink and intelligence sats.
What better way to cover up such space compute capabilities than the AI madness.
Shhh, I'm begging people, if brain-dead VCs want to waste their money on things that are obviously farcical (and not actively destructive), please let them and stop doing their due diligence for them. The alternative is that they turn their impossible amounts of capital towards societally-destructive acts like buying up all the real estate in the world and turning us back into land-slaves.
I asked Google for more information about AI datacenter in space. This was the first sentence, 'AI data centers are being developed in space to handle the massive energy demands of AI, using solar power and the vacuum of space for cooling.'
> After laughing at "the vacuum of space for cooling" I closed the page because there was nothing serious there. Basic high school physics student would be laughing at that sentence.
I tried Google and it pointed me to a ycombinator video about Starcloud https://youtu.be/hKw6cRKcqzY They launched a satellite with one H100 in on Nov 2nd.
>I mean, when you tell people that within 10 years it could be the case that most new data
centers are being built in space, that
sounds wacky to a lot of people, but not
to YC. (8:00)
To be fair, they have mirror surfaces inside. A more realistic prototype would be ultra-black for something like 10-50x better radiative heat transfer. Of course it would still be more like shitty insulation than like good conduction.
I absolutely don't understand how vacuum works. So I absolutely cannot model how a Dewar flask which has 15 billion light year thickness between the inner and outer wall - a wall that is very close to absolute zero will behave.
No, you can't. You need to radiate away all the heat being received from the sun facing half, AND excess heat from the compute. Even in theory, the non-sun-facing part doesn't give you any benefit. It's already part of the system that accounted for the temperature of the sun-facing side.
I wonder if there should be levels of "in theory". Yes theoretically black body radiation exist and well stuff cools down to near background radiation via that. But the next level is theoretical implementation. Like actually moving around the heat from source and so on. Maybe this could be the spherical cow step...
Reminds me of the hyperloop. Well yes, things in vacuum tube go fast. Now does enough things go fast to make any sense...
Heat conduction requires a medium, but radiation works perfectly fine in a vacuum. Otherwise the Sun wouldn't be able to heat up the Earth. The problem for spacecraft is that you're limited by how much IR radiation is passively emitted from your heat sinks, you can't actively expel heat any faster.
Hot objects emit infrared light no matter the conditions. The hotter the object, the more light it throws off. By radiating this light away, thermal energy is necessarily consumed and transformed into light. It's kind of wild actually
There is some medium in low Earth orbit. Not all vacuums are created equal. However, LEO vacuum is still very, very sparse compared to the air and water we use for cooling systems.
Yes. And it's an absolutely terrible way to get rid of heat. Cooling in space is a major problem because the actually effective ways to do it are not available.
I man you totally can radiate excess heat energy on earth, but your comment implies that the parents idea of radiating off excess "energy", specifically HEAT energy in space is possible, which it isn't.
You can radiate excess energy for sure, but you'd first have to convert it away from heat energy into light or radio waves or similar.
I don't think we even have that tech at this point in time, and neither do we have any concepts how this could be done in theory.
I see, yes. I was thinking more along the lines of radiating heat energy at a scale that's useable for cooling, not at the more extreme levels of over 500°C/1k fahrenheit
That's technically correct I guess, at some temperature threshold it becomes possible to bleed some fractions of energy while the material is exceedingly hot.
There's no air and negligible thermal medium to convect heat away. The only way heat leaves is through convection from the extremely sparse atmosphere in low Earth orbit (less than a single atom per cubic millimeter) and through thermal radiation. Both of which are much, much slower than convection with water or air.
Space stations need enormous radiator panels to dissipate the heat from the onboard computers and the body heat of a few humans. Cooling an entire data center would require utterly colossal radiator panels.
If you would kindly consult your Human HR Universal Handbook (2025 Edition) and navigate to section 226.8.2F, you’ll be gently reminded that it’s the responsibility of any and all employees to train their replacements.
Please consult your Human HR Universal Handbook (2025 Edition) on how to request a new copy of the Human HR Universal Handbook (2025 Edition). I believe it's in Volume III Section 9912.64.1 or thereabouts.
Typically, these sorts of things are located in the bottom of a locked filing cabinet stuck in a disused lavatory with a sign on the door saying ‘Beware of the Leopard'.
Interestingly, this comment gets a lot of downvotes.
If you don't want to help improve the world, then how are you expecting things to become better?
I understand that people don't like it that this will give Google an advantage. But what is the proper alternative? We have no non-profit organizations who could muster the money to build these systems. I suppose those who are critical of large companies would also be critical of governments building these systems.
So is what you (downvoters) propose here to just complain and do nothing about it? I'd be curious to hear what alternatives you propose.
Of course it’s stupid and it’s never going to work. The same is true for Carbon Capture and Storage, blue hydrogen, etc. It’s nonsense from the start, but it didn’t stop governments around the world to spend billions on it.
It works like this: companies spend a few millions on PR to market a sci-fi project that’s barely plausible. Governments who really want to preserve the status quo but are pressured to “do something” can just announce that they’re sinking billions in it and voila! They’re green, they’re going to save the world.
Building datacenters in the arctic also has the added benefit that sysadmins would have to take polar bear safety lessons, which would be pretty funny.
Risky/untried things aren't dumb because they're hard, they're dumb when they're more expensive/harder than cheaper/easier alternatives that already exist that do the same thing.
Even if they are a terrible idea, we should try it out. Specially if paid with private equity. Imagine the things we will learn, the STEM jobs this will create[^1], and the fact we will bootstrap other industries.
[^1]: Provided that ChatGPT doesn't hoard all of them :-)
None of these problems seem intractable, just really hard and probably not being solved soon, but one has to start somewhere... so at least the billionaires will fund some scientists and engineers who will do that work?
I know Silicon Valley runs on out there ideas and outright BS because 0.1% of the ideas pan out and pay for the other 99.9%, but this is just laughable for the reasons pointed out in the article.
Regardless of how terrible an idea it is, I wouldn't mind some billionaires funding R&D that advances the state of the art in thermal management in space.
What about on the Moon? My understanding is that heat is the killer. There you could sink pipes into the surface and use that as a heat sink. There are “peaks of eternal light” near the poles where you could get 24/7 solar power.
Latency becomes high but you send large batches of work.
Probably not at all economical compared to anywhere on Earth but the physics work better than orbit where you need giant heat sinks.
It's not a viable heat sink because it's a thermal insulator that doesn't support transport of heat. The thermal conductivity of lunar regolith is lower than rock-wool insulation,
(Imagine, for entertainment purposes, what would happen if you wrapped a running server rack in a giant ball of rock-wool insulation, 50 meters in radius).
Only way to dissipate large amounts of heat on the moon is with sky-facing radiators.
We have robust, space-worthy electronics. They're discussed in the article. You just can't get SOTA performance from them, because of fundamental physics-driven compromises.
Not if you bury it in regolith. That’s an idea for a Lunar base too. The design is called “Hobbit holes.” Bury the occupied structures in piles of basically any local mass you can bury them in.
It’s another huge problem for orbit though. Shielding would add a ton of mass and destroy the economics.
You'd have most of the problems of building in space, an abrasive quasi-atmosphere of dust, half a month of darkness every month, and not as good of a heat sink as the Earth's atmosphere.
I had this same thought and mentioned it on an ArsTechnica forum. There was reply that suggested that lunar regolith wouldn't be a good heat sink and a bit of googling makes me think this is probably true.
That said anything has to be better then almost literally nothing so I'm still holding out for datacenters on the moon.
One thing I haven't seen talked about at all: how quickly would space heat up?
I presume Earth's gravity largely keeps the exosphere it has around it. With some modest fractional % lost year by year. There is a colossal vast volume out there! But given that there's so little matter up in space, what if any temperature rise would we expect from say a constant 1TW of heat being added?
The sun’s radiation hitting earth is 44,000 terawatts. I think we’re fine with an “extra” terawatt. (It’s not even extra, because it would be derived from the sun’s existing energy.)
"Mind-bogglingly poorly thought out to the degree of a cynical money-grubbing scheme worthy of the finest cambodian slave camp" was taken and is disrespectful to the hard work and education of said slave camp's operators.
Additionally, their distributions were different. People who read Dijkstra circa 1968 started using the phrase in their own publications within a decade, whereas people who read Viorst (or had it read to them) in 1972 and following years had at least a few decades of further delay before publishing anything using the corresponding phrase.
Except you don’t build a data center, you add a GPU to an individual starlink node. If you can do that a couple hundred or thousand times you’ve got a lot of compute in space. The next question is how would you redesign compute around your distributed power and cooling profiles?
The article doesn’t talk about the actual engineering challenges. (Such as scaling down the radiative cooling design, matching compute node to the maximum feasible power profile, etc)
I’m not arguing it’ll be easy or will ultimately work, but articles like this are unhelpful because they don’t address the fundamental insight being proposed.
Starlink satellites would be pointless for doing computation because they are spread across the Earth resulting in horrible latency. AI companies spend lots of money on super fast connects within a datacenter.
Starlink with GPU might have some advantage for running edge GPU. But most Starlink customers are close to ground station and it makes a lot more sense to have GPUs there. It is a lot easier to manage them than launching new satellites which could take years.
I agree with most of this post and think the problems are harder than the proponents are making them seem.
But, 1) literally the smartest people and AI in the world will be working on this and 2) man I want to see us get to a type 2 civilisation bad.
The layout of this blog post is also very interesting, it presents a bunch of very hard items to solve and funny enough the last has been solved recently with starlink. So we can approach this problem, it requires great engineering but it’s possible. Maybe it’s as complicated as CERNs LHC but we have one of those.
Next up then is the strong why? When you’re in space, if you set the cost of electricity to zero, the equation gets massively skewed.
Thermal is the biggest challenge but if you have unlimited electricity, lots of stuff becomes possible. Fluorinert cooling, piezoelectric pumps and dual/multi stage cooling loops with step ups. We can put liquid cooling with piezos on phones now, so that technology is moving in the right direction.
For a thought experiment, if launch costs were $0/kg, would this be possible? If the answers yes, then at some point above $0/kg it becomes uneconomical, the challenge is then to beat that number.
I don't agree with the logic that "something is hard/can't be done right now" is equivalent to "this is a terrible idea and won't work."
There are dozens of companies solving each problem outlined here; if we never attempt the 'hard' thing we will never progress. The author could have easily taken a tone of 'these are all the things that are hard that we will need to solve first' but actively chose to take the 'catastrophically bad idea' angle.
From a more positive angle, I'm a big fan of Northwood Space and they're tackling the 'Communications' problem outlined in this article pretty well.
It's not that it's hard, it's that it's stupid - it's based on a misunderstanding of the physics involved which completely negates any of the benefits.
It's the opposite of engineering, where you understand a problem space and then try to determine the optimal solution given the constraints. This starts with an assumption that the solution is correct, and then tries to engineer fixes to gaps in the solution, without ever reevaluating the solution choice.
Unless thermodynamics suddenly changes, how exactly is the cooling problem being solved? Yeeting hot chunks of matter out the back? On a planetary body you have an entire massive system of matter to reject your heat into. In space, you have nothing.
The obvious solution is for half of the hardware to run on dark energy, counteracting the heat generated by the other half. Venture capitalists, use my gofundme site to give me the millions needed to research this, thanks.
That's not the argument though. The argument is "it can be done, the methods to do it are known, but the claims about space being an optimal location to locate our AI datacenters are false and the tradeoffs and unit economics of doing it makes no sense compared with building a data centre on earth somewhere with power and water, preferably not too hot.
(TLDR: the actual use cases for datacentres in space rely on the exact opposite assumption from visions of space clouds for LLMs: most of space is far away and has data transmission latency and throughput issues so you want to do a certain amount of processing for your space data collection and infrastructure and autonomous systems on the edge)
What reason is there to build datacenters in space, though? Literally, what limitation do we face in building datacenters on Earth would building them in space improve?
The surface area of the earth is the limit (which only gets sunlight half the time) and only gets 1 billionth the energy emitted by the sun vs relatively unlimited surface area of solar panels in space
There are things which are difficult and have unsolved problems, and there are things that just fundamentally make no sense.
Nobody is proposing data centers at the South Pole. This isn’t because it’s difficult. It is difficult, but that’s not the reason it’s not being looked at. Nobody’s doing it because it’s pointless. It’s a massive hassle for very little gain. It’s never going to be worth the cost no matter what problems get solved.
Data centers in space are like that. It’s not that it’s difficult. It’s that the downsides are fundamentally much worse than the advantages, because the advantages aren’t very significant. Ok, you get somewhat more consistent solar power and you can reach a wider ground area by radio or laser. And in exchange for that, you get to deal with cooling in a near perfect insulator, a significantly increased radiation environment, and difficult-to-impossible maintenance. Those challenges can be overcome, sure, but why?
This whole thing makes no sense. Maybe there’s something we just aren’t seeing, or maybe this is what happens when people are able to accumulate far too much money and nobody is willing to tell them they’re being stupid.
The one thing that space has going for itself is space. You could have way bigger datacenters than on Earth and just leave them there, assuming Starship makes it cheap enough to get them there. I think it would maybe make sense if 2 things:
- We are sure we will need a lot of gpus for the next 30-40 years.
- We can make the solar panels + cooling + GPUs have a great life expectancy, so that we can just leave them up there and accumulate them.
Latency wise it seems okay for llm training to put them higher than Starlink to make them last longer and avoid decelerating because of the atmosphere. And for inference, well, if the infra can be amortized over decades than it might make the inference price cheap enough to endure additional latencies.
Concerning communication, SpaceX I think already has inter-starlinks laser comms, at least a prototype.
You can't just "leave them there" though. They orbit at high speed, which effectively means they actually take up vastly more space, with other objects orbiting at high speed intersecting those orbits. The orbits that are most useful are relatively narrow bands shared with a lot of other satellites and a fair amount of debris, and orbits tend to decay over time (which is a problem if you're in low earth orbit because they'll decay all the way into the atmosphere, and a problem if you're in geostationary orbit because you'll lose the advantage of stationary bit for maintaining comms links). This is a solvable problem with propulsion, but that entails bringing the propellant with you and end-of-life (or an expensive refuelling operation) when it runs out. The cost of maintaining real estate space is vastly more than out right owning land.
Similarly, making stuff have a great life expectancy is much more expensive than having it optimized for cost and operational requirements instead but stored somewhere you can replace individual components as and when they fail, and it's also much easier to maximise life expectancy somewhere bombarded by considerably less radiation.
There is lots and lots and lots of space on Earth where hardly anyone is living. Cheap rural areas can support extremely large datacenters, limited only by availability of utilities and workers.
We also have to build a lot more solar and nuclear in addition of the datacenters themselves, which we need to do anyway but it would compound the land we use for energy production.
Yet a colossal number of servers on satellites would require the same energy-production facilities to be shipped into orbit (and to receive regular maintainence in orbit whenever they fail), which requires loads of land for launch facilities as well as processing for fuel and other consumable resources. Solar might be somewhat more efficient, but not nearly so much so as to make up for the added difficulty in cooling. One could maybe postulate asteroid mining and space manufacturing to reduce the total delta-V requirement per satellite-year, but missions to asteroids have fuel requirements of their own.
If anything, I'd expect large-scale Mars datacenters before large-scale space datacenters, if we can find viable resources there.
It makes sense, I would be curious to see the price computations done by the different space GPUs startups and Big Tech, I wonder how they are getting a cheaper cost, or maybe it is marketing.
Space is not much of an issue for datacenters. For one thing, compute density is growing; it's not uncommon for a datacenter to be capacity limited by power and/or cooling before space becomes an issue; especially for older datacenters.
There are plenty of data centers in urban centers; most major internet exchanges have their core in a skyscraper in a significant downtown, and there will almost always be several floors of colospace surrounding that, and typically in neighboring buildings as well. But when that is too expensive, it's almost always the case that there are satellite DCs in the surrounding suburbs. Running fiber out to the warehouse district isn't too expensive, especially compared to putting things in orbit; and terrestrial power delivery has got to be a lot less expensive and more reliable too.
According to a quick search, StarLink has one 100g space laser on equipped satellites; that's peanuts for terrestrial equipment.
Falcon heavy is only $1,500/kg to LEO. This rate is considerably undercut here on Earth by me, a weasley little nerd, who will move a kilogram in exchange for a pat on the head (if your praise is desirable) or up to tens of dollars (if it isn't).
Launching a datacenter like that carries an absurd cost even with Starship type launchers. Unless TSMC moves its production to LEO it's a joke of a proposal.
Underwater [0] is the obvious choice for both space and cooling. Seal the thing and chuck it next to an internet backbone cable.
> More than half the world’s population lives within 120 miles of the coast. By putting datacenters underwater near coastal cities, data would have a short distance to travel
> Among the components crated up and sent to Redmond are a handful of failed servers and related cables. The researchers think this hardware will help them understand why the servers in the underwater datacenter are eight times more reliable than those on land.
Starship is on a fast track to failure. It is not a cheaper way to get to orbit and will never get there at the current pace. And even if it were, it would not make getting to orbit so cheap that it would somehow make it economically viable to put a datacenter there.
You still have to build the GPUs, etc for the datacenter whether it’s on Earth or in orbit. But to put it in space you also need massive new cooling solution, radiation shielding, orbital boosting, data transmission bandwidth, and you have to launch all of that.
And then, there are zero benefits to putting a datacenter in space over building it on Earth. So why would you want to add all that extra expense?
It will make getting to orbit cheaper, significantly so, but I can't see it being rapidly reusable. Rapidly refurbishable perhaps if Starship were modular and the heat shield could be quickly swapped out on site where necessary. But being able to top off the methalox and fly again? That's a pipe dream. Orbital spaceflight isn't like air travel in any sense.
"[..] deploying a solar array with photovoltaic cells – something essentially equivalent to what I have on the roof of my house here in Ireland, just in space. It works, but it isn't somehow magically better than installing solar panels on the ground – you don't lose that much power through the atmosphere"
As an armchair layman, this claim intuitively doesn't feel very correct.
Of course AI is far from a trustworthy source, but just using it here to get a rough idea of what it thinks about the issue:
"Ground sites average only a few kWh/m²/day compared to ~32.7 kWh/m²/day of continuous, top-of-atmosphere sunlight." .. "continuous exposure (depending on orbit), no weather, and the ability to use high-efficiency cells — all make space solar far denser in delivered energy per m² of panel."
(1) Solar panels can be made much lighter in space. On Earth, panels have to withstand wind and gravity loads, flying debris, and precipitation including hail. The PV material itself doesn't have to be thick: thin film CdTe cells can be ~1 micron thick (the absorption length of the relevant photons in CdTe is something like 0.1 microns.) There has to be a protective layer to prevent solar wind ions from degrading the cells but this doesn't have to be very thick. It's not like shielding against high energy particles.
(2) Heat dissipation can be addressed by refrigeration. Yes, this takes energy, and yes that extra energy also has to be radiated. But the area of the radiator goes down as the fourth power of its absolute temperature. If you radiate 2x as much heat but at 2x the absolute temperature, the area of the radiator declines by a factor of 8. Even with inefficiencies one should be able to come out ahead by pumping the waste heat to higher temperature before radiating it.
(3) Ionizing radiation is dealt with by shielding. The amount of shielding per unit of capacity declines as you make your installation larger, by the square cube law. So this is really just a matter of scale. We're talking about potentially enormous amounts of capacity here so shielding shouldn't be a problem at scale.
Datacenters in space may not work now but in the future when we get the robots a bit better who knows? From the Google blog:
>The Sun is the ultimate energy source in our solar system, emitting more power than 100 trillion times humanity’s total electricity production. In the right orbit, a solar panel can be up to 8 times more productive than on earth, and produce power nearly continuously, reducing the need for batteries. In the future, space may be the best place to scale AI compute.
To say the quiet part out loud, I don't think any serious companies have any intention to build a data center in space. There is no benefit in actually trying this. There is however, benefit in saying you'll do it to advance a narrative and distract from the problems terrestrial data centers are facing to an audience that mostly doesn't understand how heat transfer in a vacuum works.
It can be considered as advertising. Like Coca-Cola. Not actually anything new or real most of the time. But keeping the mind-share. Making the company seem like they are on cutting-edge, visionary and futuristic. After all the scam is build on future promises. And not the current day real profits.
Classic misaligned incentives - pretendgineering is far more profitable than building stuff that works reliably and is useful.
We've moved past bullshit jobs to a bullshit economy, which operates by moving money from investors to billionaires and back again, driven by pitch deck thoughts and prayers and implied threats. ("Bail us out or everyone dies.")
I always assume, unfortunately, that once companies start to get to a certain point they become strategic, and military applications comes into play. They then probably get special consideration when it comes to funding and access. All of Musk's efforts certainly fit this paradigm.
The only real advantage is 24/7 power without having to use batteries (or some other power supply at night or when cloudy). The way solar prices are going the problem of suppling power when the sun isn’t visible is a real bottleneck.
For 24/7 solar... you are either in a sun synchronous orbit or in a very high orbit.
The sun synchronous are polar orbits ($$$) that are preferred for earth observation (so that the sun is casting the same shadows). As these are polar orbits, the satellite is not overhead all the time and getting a satellite into such an orbit takes a bit of work.
A SpaceX is at about $3k / kg to LEO. The numbers I see suggest a $20k / kg to a polar orbit.
The next option is being far enough out of the way that the earth's shadow isn't an issue. For that, instead of a 500 km sun synchronous orbit, you'd be going to 36,000 km orbit. This is a lot further from the surface, takes a lot more fuel... and it's a geostationary orbit.
However, as a geostationary orbit, these spots are valuable. Slots in this orbit are divided into slots.
https://www.astronomy.com/space-exploration/wealthy-nations-...
> There are only 1,800 geostationary orbital slots, and as of February 2022, 541 of them were occupied by active satellites. Countries and private companies have already claimed most of the unoccupied slots that offer access to major markets, and the satellites to fill them are currently being assembled or awaiting launch. If, for example, a new spacefaring nation wants to put a weather satellite over a specific spot in the Atlantic Ocean that is already claimed, they would either have to choose a less optimal location for the satellite or buy services from the country occupying the spot they wanted.
> Orbital slots are allocated by an agency of the United Nations called the International Telecommunication Union. Slots are free, but they go to countries on a first-come, first-served basis. When a satellite reaches the end of its 15- to 20-year lifespan, a country can simply replace it and renew its hold on the slot. This effectively allows countries to keep these positions indefinitely. Countries that already have the technology to utilize geostationary orbit have a major advantage over those that do not.
Furthermore, the "out of a nations control" - those slots are owned by nations. Countries would likely be very annoyed for someone to be putting satellites there without authorization. Furthermore, they only work with the countries on those areas. They also require spacing to ensure that you can properly point an antenna to that satellite.
Furthermore, geosynchronous orbits have a 0.5 second round trip lag. This could be a problem for data centers.
Misbehaving satellites in the geosynchronous orbit are also of concern ( https://en.wikipedia.org/wiki/Galaxy_15 ).
----
Putting things in these orbits is pricy. For LEO, you'd need a lot of them. For geosynchronous, the idea of servicing them is pretty much a "you can't do that" (in 10 - 20 years they use their last fuel and get pushed to a higher orbit and pretty much get forgotten about).
Satellites in geosynchronous orbit are things that need to be especially well behaved because any orbital debris in that area could really ruin everyone's day.
Compute in space doesn't make sense.
Is there an orbit which has 24/7 sun and a visibility to same location?
Geosynchronous orbits do not pass through the Earth's shadow as much as you might think. These orbits sit in the same plane as the equator, which is tilted 23.5 degrees when compared to a line from the sun to the earth.
They still pass through the earth's shadow in the weeks around the equinoxes though. Worst case is about 70 minutes of shadow.
That said, it seems more likely to me that there is no requirement to stay over the same spot on the earth, and a lower altitude sun-synchronous orbit would be used.
The real advantage is latency but who really needs that? The military may have some use cases (think remote control of drones and the link between the controllers and satellites) but the use cases are limited
There's one obvious potential application, which is caching of common requests. If something like segments of streams or any CDN contents is cached on the satellite, it reduces communication to a single hop for a large portion of traffic (IIRC, 70% or so?). Storage is very lightweight these days and failure to read cached data is not critical, so putting lots of SSDs on a LEO constellation satellite seems like a no-brainer to me if you're trying to optimize bandwidth usage.
Many of the dumb ideas being hyped in this AI bubble make sense viewed through this lens.
Data centres stirring up opposition? Sell a sci-fi vision that you will move them to Space! And reassure your over-extended investors that the data centre buildout rush you’re committing to isn’t going to get bogged down in protests and lawsuits.
The people hyping this stuff are not stupid, just their real goal (make as much money as possible as quickly as possible) has only a vague relationship to what they claim to be doing.
If Arthur C Clarke was still alive, he would be much in demand as sci-fi frontperson for these.
I think that he had more sense...
At the point, it's beginning to feel a bit like the 419 scam (where you make the details deliberately absurd so as to ward off people inclined to be sceptical early, leaving you with only the easiest marks.) SMRs! Data centres in space! "phD level AIs".
You can short the publicly traded companies that do this.
No, because to do that and not ruin myself I need to know roughly when the double will burst. Just knowing it is a bubble is not enough.
The market can, as always, remain irrational longer than you can remain solvent, or certainly for longer than _I_ can.
Like, come on, you must understand what a stupid response this is? “There is a bubble” is not a sufficient thesis to, well, do much of anything on.
> There is however, benefit in saying you'll do it to advance a narrative
Its almost as if there is good money to be made promoting bad ideas! Theranos, Wework, Tesla, NFTs, Crypto.
I am skeptical as well BUT on the cooling question, which is one of the main concerns we all seem to have, the article is doing a bit of an apples-to-oranges comparison between the ISS and a cluster of small satellites.
It cites the ISS's centralized 16kW cooling system which is for a big space station that needs to collect and shunt heat over a relatively large area. The Suncatcher prototype is puny in comparison: just 4 TPUs and a total power budget of ballpark 2kW.
Suncatcher imagines a large cluster of small satellites separated by optical links, not little datacenter space stations in the sky. They would not be pulling heat from multiple systems tens of meters away like on the ISS, which bodes well for simpler passive cooling systems. And while the combined panel surface area of a large satellite cluster would be substantial, the footprint of any individual satellite, the more important metric, would likely be reasonable.
Personally I am more concerned with the climate impact of launches and the relatively short envisioned mission life of 5 years. If the whole point is better sustainability, you can't just look at the dollar cost of launches that don't internalize the environmental externalities of stuff like polluting the stratosphere.
In theory rocket launches sound bad, with burning fuels all the way up to the top layers of the atmosphere, but it's not clear right away that we're significantly increasing the "burnt up stuff" vs say, the ~100 tons of meteorites that hit every night.
Arguments re: Methane as a non-renewable resource are of course right, except that we technically can synthesize methane from CO2 + electricity (e.g., terraform industries), but the pollution angle is presented as-is, without a systematic analysis, right?
What's the actual atmospheric burden here?
This essentially says "We dont know"
https://news.climate.columbia.edu/2025/03/04/rockets-affect-...
Starlink v2 Mini has about 35 kW of solar power at peak irradiance. 2 kW is quite far from the limit of how much juice we can pack into modern mass produced satellites.
Some of the proposals are much much bigger than this. Five GW, and 16 square kilometres.
It’s amusing that the article points out how large the radiators will have to be, when the proposals already include building giant radiators. Or that the satellites will have to be vastly larger than the ISS; surprise, surprise, that’s also part of the plan.
I mean why not just have a whole bunch of floating buoys doing computation on the ocean? They can probably get energy both from solar and from the tidal wave energy. Cooling certainly won't be an issue.
Communication might be a bit rough.
Related" "A City on Mars" (2024) [1] A useful book on why self-sustaining settlements on Luna, Mars, or earth orbit are pretty much hopeless. Remote bases that take a lot of supply, maybe, with great difficulty. The environment is just too hostile and doesn't have essential resources for self-sustaining settlements. The authors go into how Antarctic bases work and how Biosphere II didn't.
The worst real estate on Earth is better than the best real estate on Mars or Luna.
[1] https://www.amazon.com/City-Mars-settle-thought-through/dp/1...
> The worst real estate on Earth is better than the best real estate on Mars or Luna.
Very true..
Here's a recent HN link to a chilling documentary about one of the most isolated settlements in the world: https://news.ycombinator.com/item?id=46040459
I'm as critical as OP on data centers in space, but "A City on Mars" was a really badly researched book, full of errors, that completely misrepresented the would-be Mars settler position. I wouldn't take seriously anyone quoting it unless they've also read, at minimum, "The Case for Mars" as well.
https://nss.org/wp-content/uploads/NSS-JOURNAL-Critique-of-A...
I was very interested to see in that rebuttal that they explicitly called out ‘datacenters in space’ as a means of ‘exporting’ solar power to the earth.
> As the Weinersmiths point out, the ease of generating solar electricity in space is foundational to space development. They focus on the challenges in beaming power back to the Earth, but the “power” could be returned to the Earth in other ways, such as by doing energy intensive manufacturing in space, with the result that we do not need the power on the Earth itself. One modern idea that O’Neill did not consider is to move server farms in space, where power is cheap and you can dump heat into space with a black piece of metal. If this was done on a large scale, the carbon impact of data services on the Earth would drop greatly even if power is not beamed back to the Earth. There are almost certainly other ways we can use power in space to do things in space that benefit people on the Earth.
So the original article seems to think that cooling is a significant challenge and that solar power in space is not ‘that much’ more effective than on the earth, and the other that cooling is trivial and that solar power is easily obtained. I’m inclined to go with ‘space is hard’ as that seems to comport with my other readings, but obviously the critique of ‘a city on mars’ is advocating for space exploration and is so motivated to minimize the difficulties.
"One modern idea that O’Neill did not consider is to move server farms in space, where power is cheap and you can dump heat into space with a black piece of metal."
Hmmm.
> "One modern idea that O’Neill did not consider is to move server farms in space, where power is cheap and you can dump heat into space with a black piece of metal."
Minor quibble - radiators are white in the visible spectrum.
https://space.stackexchange.com/questions/8851/why-arent-the...
> The radiators on the ISS are a high-emissivity white paint, meaning that they are dark in the infrared spectrum where the heat is emitted. They are white in the visible spectrum to reflect sunlight.
> The radiators on the shuttle are have a two-layer coating: a silver reflective layer covered by a thin Teflon film. The Teflon layer is opaque to infrared light, so the high emissivity of Teflon dominates. Visible light passes through the Teflon layer and is reflected by the silver layer, so the solar absorbance is low.
https://www.nasa.gov/wp-content/uploads/2021/02/473486main_i... - page 14 shows them extended and testing at Lockheed.
One mistake that the article seems to make is to assume that the data center is in one huge satellite.
I think a better model would be a fleet of rack or server level satellites. That significantly reduces the heat and cooling requirements and improves redundancy since losing a single satellite sure to radiation would be less significant. Further, due to economies of scale these satellites could be produced in mass, similar to the starlink satellites of today.
One issue is that these satellites would be to be connected via high bandwidth free space optical links instead of Ethernet, requiring precise formations, but that is currently being tested by multiple companies.
That being said, I don't see this ever being cheaper than terrestrial data centers. I just don't think the idea is as stupid as the article implies - it just requires doing things differently than NASA has done in the past.
Datacenters in space is about circumventing nation states masked as ambitions to generate more power.
Follow the rationale:
1. Nation states ultimately control three key infrastructure pieces required to run data centers (a) land (protected by sovereign armed forces) (b) internet / internet infra (c) electricity. If crypto ever became a legitimate threat, nation states could simply seize any one of or all these three and basically negate any use of crypto.
2. So, if you have data centers that no longer rely on power derived from a nation state, land controller by a nation state or connectivity provided by the nation state's cabling infra, then you can always access your currency and assets.
That’s ridiculous. Space is the least nation-state-dependent place to do computing in existence.
All proposed space computing has an incredibly short orbital lifespan (less than 5y).
Every single space launch capable rocket provider in the world is financially, regulatorily, and militarily joined at the hip to a single government. No launches are taking place without that government’s say-so.
Also, space infrastructure is incredibly vulnerable to attack by nation-states as many others in this thread have pointed out.
That really depends on the cost asymmetry between building + launching sats being cheaper or more expensive than taking down all those sats.
https://en.wikipedia.org/wiki/Anti-satellite_weapon
My favorite F-15 kill:
https://en.wikipedia.org/wiki/ASM-135_ASAT
The military have developed other ways to bring down satellites.
https://en.wikipedia.org/wiki/Ionospheric_heater
Whats less well known is as the Ionsphere heats up the upper atmosphere, it bulges out into space like a tyre sidewall bulge. This has the effect of putting an atmosphere in the path of LEO satellite, which then causes the LEO satellite to fall to earth because they are not designed to travel through an atmosphere.
Joule heating is the most important one which can alter the thermospheric dynamics quite significantly.[1]
[1] https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/201...
This is one of the early tipping points in the background of the game "Eclipse Phase", which I always found interesting:
--- >8 ---
The power of nation states is rooted in control of land and safety, as well as resources, which is an extension of the control of land. But once mining asteroids became economically viable, the connection between land and resources disappeared. Once space habitation in space and secretly developed weapon systems from space became viable, the connection between safety, habitation and land disappeared.
This allowed corporations and new organizations to rise to power large enough to challenge nation states. Those in power did feared to lose their power, which caused the great war which gave rise to the grey mass and destroyed earth.
--- 8< ---
It's a very cool back story, which gives rise to a rogue nanite swarm (the gray mass), which forces an evacuation of earth within days. The only way this was even possible was by uploading human minds onto storage and planting them in robots later on. Naturally, most humans are then forced to work for these corporations. Other humans are still biological and they don't like robots, to say the least.
If a company were to go on its own and build data centers in space only to avoid nation state jurisdiction, they better be prepares to defend that hardware in space.
If a country doesn't like what is happening they can shoot it down, and with no humans onboard or nations claiming jurisdiction there really isn't much to stop them or to answer for.
By the same argument Google could start literal star wars by blowing up AWS data centres. Because it is the wild west up there right? No pesky laws.
Putting data centers on ships in international waters would be just as effective at evading government control (i.e. not very) while being orders of magnitude easier and cheaper to build and operate.
Recently the USA blew out some some boats in international waters and came back to finish off the survivors, despite thin evidence and no due process, while maintaining that it was legal. If those data centers on ships ever become declared as a 'threat to national security' then they might get the same treatment.
I think GP's point is that an advanced nation-state could just as easily shoot down an orbiting data center as an oceanic data center and that "international space" offers an equally flimsy defense as "international waters" but a much larger price.
Antisatellite weapons are expensive and rare, and also woefully inadequate for dealing with megaconstellations.
If there's one large orbital datacenter, then sure, ASAT is a threat to it. But if it's a dispersed swarm like the Starlink system?
Good luck making a dent in that. You'd run out of ASAT long before Musk runs out of Starlink.
Lasers
You only need to destroy a few. Then you have a cloud of debris that will take down the rest or at the very least force them to use all their fuel making evasive manoeuvres.
And they'd get away with it too if it weren't for that pesky orbital mechanics.
Not really. Space is too large.
On the contrary, orbital positions are quite limited. And space debris is already a large issue.
Blow up the ground stations. Or the CEO.
This would be equally true in space.
If those ships chose to not fly a flag, they'd even have justification to do so. And if they did choose to fly a flag, then that country would have the responsibility to police them, and is the US complained to that country, that country might just withdraw protection anyway. Data center ships just want to loiter where convenient, they're not cigarette boats flying along at 100mph... no way to evade a navy that wants to blow them out of the water.
They've always been able to do this.
Microsoft was talking about submarine data centers powered by tidal forces in the early 2000s.
There have been talks of data centers on Sealand-like nation states.
Geothermal ...
Exotic data center builds will always be hyped. Always be within the realm of feasibility when cost is no object, but probably outside of practicality or need.
Next it'll be fusion-powered data centers.
Commonwealth Fusion Systems called dibs on next last year by saying they’re gonna have a Dominion (Virginia) commercial site up and running in the early 2030s.
https://cfs.energy/news-and-media/commonwealth-fusion-system...
Is there a way I can take bets on this not happening? Because I’d sure like to.
Despite the massive PPAs that have already been signed on a chunk of the plant’s planned output I also find it very hard to believe.
Except the people that run and manage that satellite will be on earth, under some nation state's rules...
corporations will use their knowledge in tax dodging to avoid that too.
If they're already well versed in dodging fiscal rules, why do they need a space computer?
Physical location is difficult to dodge unfortunately.
Fiscal rules are sort of man made.
The Outer Space Treaty is very very clear: anything launched into space is the responsibility of the country that launched it. Even if a private company payts for it and operates it, it's still the responsibility of the launching nation. Even if you launch from international waters, your operating company is still registered to a specific country, and the company is made up of citizens of one or more countries, and it is those countries which are responsible for the satellites. Those countries, in fact, have the responsibility to make sure that their citizens follow their laws and regulations. Unless you and your entire team are self-sustaining on that datacenter in outer space (maybe possible a century from now? Maybe not possible ever), you will be hunted down by the proper authorities and held to account for your actions. There is no magic "space is beyond the law" rules; it is just as illegal- and you are just as vulnerable to being arrested- for work done on a datacenter in space as work done on a datacenter on the ground.
Spy satellites maneuver so that no one can tell who launched them, or when. If these satellites can do the same, good luck pinning responsibility on someone on the ground. Hell, with Musk's low orbit network, he could probably even provide connectivity to them in a plausibly-deniable manner.
A data center on an orbit that is only known to the operators makes it difficult to use as a data center in a meaningful way - where do you point your uplink?
Spy satellites are individual craft. Proposals tossed about suggest significant constellates to give sufficient coverage to the land.
Suggestions involving square kilometers of solar power are not exactly things that would be easy to hide.
https://youtu.be/hKw6cRKcqzY (from YCombinator)
> Data centers in space. The problem is that data centers take up a ton of space and they need a huge amount of energy. Enter StarCloud. This is the beginning of a future where most new data centers are being built in space. They're starting small, but the goal is to build massive orbital data centers that will make computing more efficient and less of a burden on the limited resources down here on Earth.
These aren't small things. You can't hide it.
> And so we're building with a vision to build extremely large full 40 megawatt data centers. It's about 100 tons. It's what you can fit in one full Starship halo bay.
Bitcoin is a great example of something outside of jursidictions. Now look at how much BTC the FBI has seized. In practice, power is gonna power. The US, Russia or China can take out your data centre unless you play by whatever the rules are. If not physically blow up you need to trade, you need a country for ground operations etc. You need a downlink. Being in space meaning no jurisdiction is plain rediculous.
This is the only "advantage" I can see with space-based datacenters. Crypto will remain a joke but putting devices beyond the reach of ground-based jurisdictions is a libertarian dream. It will probably fail - you still need plenty of ground infrastructure.
Data centers in space is about leading investors to circumvent their brains and jump on the hype train at worst, and developing technology around data center infrastructure at best.
Microsoft did something similar with their submarine data center pilots. This gets more press because AI.
I'm sorry, but this is stupid. It's the same dumb thinking behind Sealand: "we're outside state borders! nobody can touch us!", which was only true as long as nobody cared what they were doing. Once Sealand actually started angering people, the Royal Navy showed up and that was that. "Datacenters in space" wouldn't fare any better: multiple nations have successfully tested anti-satellite weapons.
> Once Sealand actually started angering people, the Royal Navy showed up and that was that.
What did the royal navy do? There is no mention of the UK using force against sealand in either the Wikipedia page or this BBC article about sealand. (Though obviously the royal navy could retake sealand if they wanted)
https://en.wikipedia.org/wiki/Principality_of_Sealand
https://www.bbc.com/news/uk-england-suffolk-41135081
Nation states can fire missiles at your space datacenter, bruh.
Or just triangulate any signals being sent to it, and fire missiles at the source.
Or just blast it with a laser...
As someone with a similar background to the writer of this post (I did avionics work for NASA before moving into more “traditional” software engineering), this post does a great job at summing up my thoughts on why space-based data centers won’t work. The SEU issues were my first though followed by the thermal concerns, and both are addressed here fantastically.
On the SEU issue I’ll add in that even in LEO you can still get SEUs - the ISS is in LEO and gets SEUs on occasion. There’s also the South Atlantic Anomaly where spacecraft in LEO see a higher number of SEUs.
As someone with only a basic knowledge of space technology, my first thought when I read the idea was "how the hell are they going to cool it".
> On the SEU issue I’ll add in that even in LEO you can still get SEUs
As a sibling post noted, SEUs are possible all the way down to sea level. The recent Airbus mass intervention was essentially a fix for a badly handled SEU in a corner case.
Single event upsets are already commonplace at sea level well below data center scale.
The section of the article that talks about them isn’t great. At least for FPGAs, the state of the art is to run 2-3 copies of the logic, and detect output discrepancies before they can create side effects.
I guess you could build a GPU that way, but it’d have 1/3 the parallelism as a normal one for the same die size and power budget. The article says it’d be a 2-3 order of magnitude loss.
It’s still a terrible idea, pf course.
It strikes me that neutral network inference loads are probably pretty resilient to these kinds of problems (as we see the bits per activation steadily decreasing), and where they aren't, you can add them as augmentations at training time and they will essentially act as regularization.
If you're using GPUs, you're running AI workloads. In which case: do you care?
One of the funniest things about modern AI systems is just how many random bitflips they can tank before their performance begins to really suffer.
Sounds like it would remove a lot of the benefits gain from more solar power.
The only advantage I can come up with is the background temperature being much colder than Earth surface. If you ignored the capex cost to get this launched and running in orbit, could the cooling cost be smaller? Maybe that's the gimmick being used to sell the idea. "Yes it costs more upfront but then the 40% cooling bill goes away... breakeven in X years"
Strictly speaking, the thermosphere is actually much warmer than the atmosphere we experience--on the order of 100's or even a 1000 degrees Celsius, if you're measuring by temperature (the average kinetic energy of molecules). However, since particle density is so low, the number of molecules is quite low, and so total heat content of the thermosphere is low. But since particle count is low, conduction and convection are essentially nonexistent, which means cooling needs to rely entirely on radiation, which is much less efficient than other modes at cooling.
In other words, a) background temperature (to the extent it's even meaningful) is much warmer than Earth's surface and b) cooling is much, much more difficult than on Earth.
Technically radiation cooling is 100% efficient. And remarkably effective, you can cool an inert object to the temperature of the CMBR (4K) without doing anything at all. However it is rather slow and works best if there's no nearby planets or stars.
Fun fact though, make your radiator hotter and you can dump just as much if not more energy then you would typically via convective cooling. At 1400C (just below the melting point of steel) you can shed 450kW of heat per square meter, all you need is a really fancy heat pump!
Your hypothetical liquid metal heat pump would have a Carnot efficiency of only 25%.
How much power would a square meter at 1400C shed from convection?
I dont have firm numbers for you since it would depend on environmental conditions. As an educated guess though, I would say a fucking shit ton. You wouldn't want to be anywhere near the damn thing.
Not much in space; There's almost no matter to convect!
A sports car radiator has about that size and dumps 1 MW without boiling the coolant.
A car's "radiator" doesn't actually lose heat by radiation though. It conducts heat to the air rushing through it. That's absolutely nothing like a radiator in a vacuum.
The question was about comparing the 1400KW of radiative cooling to how much convective coolig you could get from the same radiator on Earth.
That's the point. Forced air cooling is way more efficient than radiative cooling.
Is it an advantage though ? One of the main objections in the article is exactly that.
There's no atmosphere that helps with heat loss through convection, there's nowhere to shed heat through conduction, all you have is radiation. It is a serious engineering challenge for spacecrafts to getting rid of the little heat they generate, and avoid being overheated by the sun.
I think it is an advantage, the question is just how big, and assume we look only at ongoing operation cost.
- Earth temperatures are variable, and radiation only works at night
- The required radiator area is much smaller for the space installation
- The engineering is simple: CPU -> cooler -> liquid -> pipe -> radiator. We're assuming no constraint on capex so we can omit heat pumps
A typical CPU heatsink dissipates 10-30% of heat through radiation, and the rest through convection. In space you're in a vacuum so you can't disipated heat through convection.
You need to rework your physical equipment quite substantially to make up for the fact you can't shed 70-90% of the heat in the same manner as you can down here on Earth
Radiators on earth mainly do it to air, there's no air in space.
This question is thoroughly covered in the linked article.
Pardon, but the question of "could the operational cost be smaller in space" is almost not touched at all in the article. The article mostly argues that designing thermal management systems for space applications is hard, and that the radiators required would be big, which speaks to the upfront investment cost, not ongoing opex.
Ok, sure, technically. To be fair you can't really assess the opex of technology that doesn't exist yet, but I find it hard to believe that operating brand new, huge machines that have to move fluid around (and not nice fluids either) will ever be less than it is on the surface. Better hope you never get a coolant leak. Heck, it might even be that opex=0 still isn't enough to offset the "capex". Space is already hard when you're not trying to launch record-breaking structures.
Even optimistically, capex goes up by a lot to reduce opex, which means you need a really really long breakeven time, which means a long time where nothing breaks. How many months of reduced electricity costs is wiped out if you have to send a tech to orbit?
Oh, and don't forget the radiation slowly destroying all your transistors. Does that count as opex? Can you break even before your customers start complaining about corruption?
Maintenance will be impossible or at least prohibitively expensive. Which means your only opex is ground support. But it also means your capex depreciates over whatever lifetime these things will have with zero repairs or preventive maintenance.
But ground support will not be cheap. You need to transfer a huge amount of data, which means you need to run and maintain a network of ground stations. And satellite operations are not as cheap as people like to think either.
Cooling is more difficult in space, yes it's colder, but transferring heat is more difficult.
But the cooling cost wouldn’t be smaller. There’s no good way to eliminate the waste heat into space. It’s actually far far harder to radiate the waste heat into space directly than it would be to get rid of it on Earth.
Which is why vacuum flask for hot/cold drinks are a thing/work. Empty space is a pretty good insulator as it turns out.
It’s a little worrying so many don’t know that.
I don't know about that. Look at where the power goes in a typical data center, for a 10MW DC you might spend 2MW just to blow air around. A radiating cooler in space would almost eliminate that. The problem is the initial investment is probably impractical.
>99.999% of the power put into compute turns into heat, so you're going to need to reject 8 MW of power into space with pure radiation. The ISS EATCS radiators reject 0.07 MW of power in 85 sq. m, so you're talking about 9700 sq. m of radiators, or bigger than a football field/pitch.
How do you propose to get 10MW of heat from the computers out to the radiators?
Same way we’ve always done it.
https://en.wikipedia.org/wiki/External_Active_Thermal_Contro...
I.e. pumps, just like on the ground.
Now scale the radiator size for your 8MW datacenter.
Things on earth also have access to that coldness for about half of each day. How many data centers use radiative cooling into the night sky to supplement their regular cooling? The fact that the answer is “zero” should tell you all you need to know about how useful this is.
Look up Tech Ingredients episode on Radiative Paint.
The fact that people aren’t using something isn’t evidence that it’s not possible or even a great idea, it could be that a practical application didn’t exist before or someone enterprising enough hasn’t come along yet.
The atmosphere is in the way even at night, and re-radiates the energy. The effective background temperature is the temperature of the air, not to mention it would only work at night. I think there would need to be like 50-ish acres of radiators for a 50MW datacenter to radiate from 60 to 30C. This would be a lot smaller in space due to bigger temp delta. Either way opex would be much much less than average Earth DC (PUE almost 1 instead of run-of-the mill 1.5 or as low as 1.1 for hyperscalers). But yeah the upfront cost would be immense.
I think you’re ignoring a huge factor in how radiative cooling actually works. I thought the initial question was fine if you hadn’t read the article but understand the downvotes due to doubling down. Think of it this way. Why do thermoses have a vacuum sealed chamber between two walls in order to insulate the contents of the bottle? Because a vacuum is a fucking terrible heat convector. Putting your data center into space in order to cool it is like putting a computer inside of a thermos to cool it. It makes zero fucking sense. There is nowhere for the heat to actually radiate to so it stays inside.
Pardon but this doesn't make sense to me. A 1 m^2 radiator in space can eliminate almost a kilowatt of heat.
>vacuum is a fucking terrible heat convector
Yes we're talking about radiating not convection
At what temperature?
And a kilowatt from one square meter is awful. You can do far more than that with access to an atmosphere, never mind water.
Breakeven in X years probably makes sense for storage (slow depreciation), not GPUs (depreciates in like 4 years)
I think by far the most mass in this kind of setup would go into the heat management, which could probably last a long time and could be amortized separately from the electronics.
How would the radiators be useful if the electronics no longer are? Unless you can repurpose the radiators once the electronics are useless, which you can't in space, then the radiators' useful lifetime is hard limited by the electronics' lifetime.
There are lots of reasons why keeping data centers on the ground might be cheaper but the article seems to be skipping over a few things.
1) ISS is about 30 years old. It's hardly the state of the art in solar technology. Also, it's much easier to get light to solar panels far a larger part of the time. Permanently in some orbits. And of course there is 0% chance of clouds or other obstructions.
2) We'll have Starship soon and New Glenn. Launching a lot of mass to orbit is a lot cheaper than launching the Space Station was.
3) The article complains about lack of bandwidth. Star Link serves millions of customers with high speed, low latency internet via thousands of satellites.
4) There have been plans for large scale solar panels in space for the purpose of beaming energy down in some form. This is not as much science fiction as it used to be anymore.
5) Learning effects are a thing. Based on thirty years ago, this is a bad idea. Based on today, it's still not great. But if things continue to improve, some things become doable. Star link works today and in terms of investment it's not a lot worse than a lot of the terrestrial communication networks it replaces. The notion would have been ridiculous a few decades ago but it no longer is.
In short, counter arguments to articles like this almost write themselves.
Solar panel performance is not the limiting factor in space. Thermal management is. Better solar panels don't help you here. Neither does permanent sunshine -- without the capability to radiate more heat at night, you've made the thermal management problem immensely worse.
Rockets: Launching no mass to orbit is even cheaper still.
Bandwidth: You do realize that even starlink speeds are crazy slow and high latency compared to data center optical connections? Fiber and copper always win out over wifi. With space, you are stuck with wifi. (Oversimplified, but accurate.)
Space solar power: there has been talk of this for half a century, yes. It never materialized because, like space data centers, it doesn't make economic sense.
1) ISS is about 30 years old. It's hardly the state of the art in solar technology.
Domestic solar panels are heavy, and dont need to deal with hypersonic sand blasting. even at that height, you are in shadow every 90 minutes.
> 3) The article complains about lack of bandwidth. Star Link serves millions of customers with high speed, low latency internet via thousands of satellites.
Right. First power and heat are a massive pain to deal with. You need megawatts to run a datacentre. A full rack of GPUs (48u, 96 GPUs) is around 40-70kw. It also weighs a literal ton.
You also need to be able to power that in the time when you are in darkness. BUT! when you are zooming around the earth every 90 minutes, you can't maintain a low latency connection, because the distance between you and the datacentre.
That means geostationary, as that solves most of your power issues, but now you have latency and bandwidth issues. (oh and power, inverse square law and bandwidth are related)
> 5) Learning effects
Great, but it gets us nothing.
> even at that height, you are in shadow every 90 minutes.
There are orbits that stay in permanent sunlight, even in LEO.
There is one. It is the sun synchronous dawn/dusk orbit.
https://en.wikipedia.org/wiki/Sun-synchronous_orbit
> Special cases of the Sun-synchronous orbit are the noon/midnight orbit, where the local mean solar time of passage for equatorial latitudes is around noon or midnight, and the dawn/dusk orbit, where the local mean solar time of passage for equatorial latitudes is around sunrise or sunset, so that the satellite rides the terminator between day and night.
The dawn dusk orbit is in constant sunlight. The noon-midnight orbit isn't.
Those orbits (and their corresponding constellations) lack 100% availability for a ground station.
Furthermore, a polar orbit launch is quite a bit more expensive since it requires a significant change in inclination.
> In short, counter arguments to articles like this almost write themselves.
Yes, arguments that are facts-and-numbers-free are easy to write, but that applies to any topic, not just space data centers.
Can you please tell me your credentials compared to someone who actually built material that went into space? Like the author of the article
It’s not about things improving. This isn’t a great idea that’s not yet feasible, the way ubiquitous satellite communication was. This is a fundamentally bad idea based on the physics, not the technology.
Satellites are so much more expensive than just running a wire, so why is satellite communication desirable? Because one satellite can serve many remote places for less than it costs to run a wire to all of them, it can serve the middle of the ocean, it can serve moving vehicles. These are fundamental advantages that make it worthwhile to figure out how to make satellite communication viable.
Data centers in space offer no fundamental advantages. They have some minor advantages. Solar power is somewhat more available. They can reach a larger area of ground with radio or laser communication. And that’s about it. Stack those advantages against the massive disadvantages in cooling, construction, and maintenance. Absent breakthroughs in physics that allow antigravity tech or something like that, these advantages are fundamental, not merely from insufficient technology.
It is not a good idea listening to experts tell you what can't be done. Science and technology progresses one funeral at at time. Einstein's ideas were crazy for classical scientists and Heisenberg's for Einstein.
The most important thing is making space access ten to one hundred times cheaper with reusable rockets. Then a lot of the problems in the article will not be problems at all.
E.g ISS was designed and created when access to space was extremely expensive. Solar technology and batteries was extremely bad but also super expensive.
You can not use convention but radiation works incredibly well and you can also use the thermal technology of mobile devices.
The most important thing being cheap is that access to the Space become possible for way more people with creativity. Not just a few people with academic titles but people with practical engineering and scientific mastery (that certainly run circles around them on real projects).
There are so many opportunities to use creativity in space, with possibilities that do not exist on earth. For example you can spin or rotate things super fast and so you could have convention inside the machines that rotate.
Interesting point actually. yeah, when spacex was trying to build a reusable rockets, many traditional rocket scientists said that even if you are able to recover stages of the rocket, you still need to refurbish and test a great number of parts, and it just isn’t this panacea for lowering rocket costs (for example, the space shuttle, which was reusable spacecraft, but was super expensive to launch).
When spacex finally got falcon 9 reusability working (and am no expert in this) but from what I read, the pundits were partially right and partially wrong. Yes, refurbishment and testing on the Falcon 9 does cost a lot, but it still brings down the cost significantly (just looked it up, their saying nowadays, the cost savings is something like 70%, which actually is huge). And as importantly, you don’t have to build a new rocket for every launch, and once you get your refurbishment process down like clockwork, you can relaunch them quite often.
So maybe data centers in space won’t be like ones on earth, but they still might be very useful… One idea is that they could become true “space” data centers, that supply powerful computing for satellites near by. This way satellites could get access to much more powerful computing, while still being small themselves (but again, am no expert in this, so maybe this idea also has many holes, for example why not just offload processing to ground based data centers).
Selection bias.
Science is very very very rarely disrupted by a small group of visionaries in the same way business or technology are.
Substitute “perpetual motion machines” for “datacenters in space”. For very Heisenberg and Einstein there are thousands of crackpots who wasted huge amounts of (often other people’s) money trying to build perpetual motion machines. None of them were remembered.
The overwhelming majority of real scientific advancement is slow, grinding, difficult, incremental, and group-based.
That doesn't sell though, so people very often ignore it, even when most recent innovations are due to that, like the atomic bomb.
Substitute “perpetual motion machines” for “datacenters in space”.
This is an absurd strawman. A datacenter in space doesn't violate any fundamental physical laws. Science would not be "disrupted" if engineers made it economically feasible for certain use-cases.
It's totally reasonable to doubt that e.g. >1% of Vera Rubins are going to wind up deployed in space, but fundamentally this is a discussion about large profitable companies investing in (one possible) future of business and technology, not a small group of crackpot visionaries intending to upend physics.
Starlink sounded fairly nuts when it was first proposed, but now there's thousands of routers in space.
I think it's a great article that should discourage a lot of people to waste resources.
To really do it you have to treat this article as a to-do list of challenges to overcome. If you have no ideas on how to address those challenges you should not start.
The idea that science progresses by lone wolf geniuses disrupting the status quo is simply false. It makes a good story for low budget documentaries, but it is basically never true.
Please don't propagate the myth that Einstein couldn't wrap his head about Heisenberg.
The EPR paper says otherwise and Bohr's response to it was incomprehensible (and still is).
Einstein was simply saying science should not stop looking into the why.
What are the fundamental advantages of space-based data centers over terrestrial ones? Certainly not cooling or radiation shielding. Those are almost free on Earth. A Zero-G environment could have some benefits regarding the total size of the construction, but of course being in Earth orbit means Zero-G but does not mean no gravity. Anything in LEO will require constant station-keeping maneuvers, and the more massive the data centers, the more fuel required. Power generation could theoretically be better, but even if you had a 100% efficient PV solar shield, you still need to radiate away the same amount of energy at a rate at least equal to that to maintain thermal equilibrium.
You could say this is all just a question of materials science, and maybe it is, but it’s not anything that makes any sense at all today, nor is it something I think anyone should expect to be up and running in the next century.
> The most important thing being cheap is that access to the Space become possible for way more people with creativity. Not just a few people with academic titles but people with practical engineering and scientific mastery (that certainly run circles around them on real projects).
Agreed! Real estate is incredibly cheap in space until Saudi money and private equity figure out a way to make it a scarce resource. Also, we can build massive single suburban homes in space! No need to build vertical and public transit. Just give everyone a rocketship to travel to the nearest space McDs drive through!
Counterpoint: oceangate
Sometimes when people tell you something can't be done they're right. No amount of gumption will cancel out physics.
I always believed thermal conductivity to be one of the hardest problems in space.
Today the way we diffuse temperature is via the air itself, and without air to carry heat away from components we don’t really have very much to work with.
I know space is cold, but diffusing the cold onto the warm is an ongoing problem as far as I understood it.
Which is why for example of nuclear submarines would not bode well in space, the internal temperature would just continue to rise until eventually the thing will become an oven floating through the solar system.
Even diffusion into air is too slow for some use cases. The whole complaint of datacentres "consuming" water is due to heating it and dumping it back or evaporating it for cooling. This is done because mass air cooling is much less efficient and requires lots of energy to run the fans to force the air through the heat exchangers, which is also extremely loud. And that is, in turn, much more effective than passive radiation, even if you have a ~3K background.
The ISS ammonia-based active heat rejection system is Two units, each 13x3 metres in size and each unit can radiate 35kW.
So to radiate a "mere" 1MW, you need a quarter-acre of radiator. A square km per GW.
The engineering is obviously more than tricky because you have lots of plumbing, gigantic flat structures, and you can't have the radiators facing each other or the sun. Moreover, unlike the ISS, if you want to run the system at full whack the whole time on solar power, it's never in shadow. Which you presumably do want, as that's the putative point of the whole thing. You also can't be sending up service missions without the cost exploding even further, so hopefully you can design everything to last the 5 years despite each handful of fully loaded GPU racks requiring a structure somewhere around the size of the ISS, humankind's crowning glory of high technology, to support.
The comment you were replying to mentioned this. Yes you cant remove heat via convection, but you can use radiators to emit heat as radiation into space.
You need HUGE radiators to emit a lot of low-temp waste heat into space. That kills this idea right there.
There are 8,000+ Starlink satellites in orbit right now. Each one has about 30 square-meters of solar panels. That's 240,000 square meters. ISS has 25,000 square meters, so SpaceX has already launched almost 10-times the solar panels of ISS.
The next generation Starlink (V3) will have 250 square meters of solar panels per satellite, and they are planning on launching about 10,000 of them, so now you're at 2.5 million m^2 of panels or 100 times ISS.
All those satellites have their own radiators to manage heat. True, they lose some heat by beaming it to the ground, but data center satellites would just need proportionally larger radiators.
And, of course, all those satellite have CPUs and memory chips; they are already hardened to resist space radiation (or else they wouldn't function).
Almost every single objection to data centers in space has already been overcome at a smaller scale with Starlink. The only one that might apply is cost: if it's cheaper to build data centers on Earth, then space doesn't make sense (and it won't happen). But prices are always coming down in space, and prices on Earth keep going up (because of environmental restrictions).
> The only one that might apply is cost: if it's cheaper to build data centers on Earth, then space doesn't make sense (and it won't happen).
So the only problem left to be solved is that space datacenters would be millions of times more expensive per unit of compute than a ground based datacenter. And cost millions of times more to maintain.
Starlink cost maybe $10 billion. A 100,000 gpu data center costs between $20 and $40 billion to build.
Also remember that data centers last for about 5 years; after that the gpus are obsolete. That’s no different than the lifetime of a Starlink satellite.
Starlink solar panels generate at best 200 W/sqm on average. Even with 2.5 million square metres, that is a total of half a gigawatt. And the cost is not to be ignored! Most of the cost of these data centres is in the GPUs themselves, so you need to add that to the cost of building out the constellation. Unless you are arguing that the cost of supporting infrastructure (cooling, power, etc) costs $10bn to support half a gigawatt of GPUs in the typical data centre, then your numbers are simply way off.
>Almost every single objection to data centers in space has already been overcome at a smaller scale with Starlink
Did you not read the article? It had many objections that make it clear datacenters in space are unworkable...
Starlink is already a small data center! It has power, radiators, and compute!
It needs to be scaled up, but there is no obstacle to that (at least none that the article mentions).
The only valid objection is cost, but space prices keep dropping and earth prices keep rising.
> Starlink is already a small data center! It has power, radiators, and compute!
It is not. This is like saying your phone is already a small data centre. While technically true, we're not talking about the same scale here. StarLink's compute power is a tiny fraction of a modern data centre GPU/TPU. Most of the power budget goes into communication (i.e. its purpose!).
At what price per MW of load?
The Starlink constellation cost $10 billion. That’s comparable to a small data center (maybe 50,000 gpus).
If launch costs keep dropping and environmental costs keep rising, space based data centers will make sense.
Land cost will also start to matter, but probably not at the scale that Starlink is doing. Regardless, orbitals are real estate.
What a ridiculous waste of money.
What? Starlink made $72,000,000 in net profit last year. How is that a waste of money?
The facts you quoted just made me even more convinced that space-based datacenters will not be cost effective any time soon. If an entire generation of satellites costing many billions of dollars can't power more GPUs than a single terrestrial datacenter, how could it possibly be cost effective?
A data center costs $20 to $40 billion! And launch costs keep dropping.
Plus, environmental costs of data centers keep rising.
I think it's important to be distinct here... These "Space DC" companies are not showing up on some Techy-Shark-Tank (or walking into VC meetings) with a promise to investors that they have an established strategy which will pay off.
IMO, they are just answering the question: "If we pour 100B into R&D, could it have a reasonable chance at succeeding?".
For Nvidia (or these other massive companies) the investment is chump change.
100B is roughly NVIDIA’s yearly profit
Always remember the magic words: dual use technology. The people pushing these aren't saying to you that they want to build data centers in space because conventional data centers are at huge risk of getting bombed by foreign nations or eventually getting smashed by angry mobs. But you can bet they're saying that to the people with the dual-use technology money bag. Or even better, let them draw that conclusion themselves, to make them think it was their idea - that also has the advantage of deniability when it turns out data centers in space was a terrible solution to the problem.
It is far easier to build them at remote places and bunkers (or both). Even at the middle of the ocean will make more sense and provide better cooling (See Microsoft attempt at that).
Not exactly at the middle but close to shore is pretty good too, a lot of solar and wind around to feed the compute.
One of these projects is bonkers IMO: china-has-an-underwater-data-center-the-us-will-build-them-in-space
https://www.forbes.com/sites/suwannagauntlett/2025/10/20/chi...
it is not far easier to distribute content from a bunker than from the space.
Did a not accidentally sneak in there? Because serving data from bunkers is done quite a bit right now.
The reason why we don't see satellite-targeting missiles is not because the problem is hard. All relevant actors are capable of that.
All relevant actors are also capable of destroying ground-based data centres, but somehow that's not a huge problem for data centres.
The only vaguely valid dual use technology I can see coming out of this is improving space-rated processing enough that deep space probes sent out to Uranus or whatever can run with more processing power than a Ti-82 and thus can actually do some data processing rather than clogging up the deep space network for three weeks on an uplink with less power than a lightbulb
Who knows what tech is in space already. Maybe an “AI data center in space” would be the equivalent of a flock camera for an entire region.
At this point I wouldn't be surprised if a non zero number of pitch meetings start with, "in order to not disrupt your life too much as the mobs of the starving and displaced beat down your door"
What makes an orbital facility at less risk of getting bombed?
Probably needs more delta-v to match orbit than a suborbital ICBM would. Not less risk—just more expensive. Depends how valuable the target is.
Nah, they are pretty similar in difficulty for interception - the first US ASAT program used essentially the same Nike Zeus missiles used for ABM duty during the late 50s
not really. Suborbital vehicles achieve orbital heights. It's actually probably easier since you don't need a payload. The velocity alone will do the trick.
Except you don't. You only need to match velocities if you want to dock with something.
Hitting something in orbit just requires you to be in the way at the right time.
Basically an intercept is a lot easier.
Because its stupid, not that its hard.
You want to push things out of orbit not turn a massive structure into a supersonic shard field for 20 years
In addition to the ludicrous unworkable physics, as it turns out, datacenters need people servicing things all the time. Even if you could get those measly three racks into space, they'd function about a month before some harddisks were failing, network switches were down, some crap breaks in the cooling system, power system short, breakers trip, etc, and on and on.
So obviously we're not going to be some SREs into space to babysit the machines. Have everything fail in place? Have robots do it? What about the regular supply missions to keep replacing all the failing hardware (there's only so many spare HDDs you can have on hand).
The whole thing is farcical.
Nah; let it fail in place.
See also: Any on-prem horror show that budgeted for capex, rent, cooling, network and power, but not maintenance.
Yes. Anyone who thinks you can ship a datacenter to space and save has never managed a datacenter.
> So obviously we're not going to be some SREs into space to babysit the machines.
Shut up! This is the chance for one of us to go into space! I don't care if all I'm doing is swapping 1U pizza boxes in the cold hard vacuum of space, I'm down!
Plus, in space, their electronic components would experience much more radiation (and the effects on components). They could build with rad-hardened components but those are both more expensive and several generations older than SOTA found in the habitable zone.
So many ideas involving AI just seems to be built off of sci-fi (not in a good way), including this one. Like sci-fi, there are little practical considerations made.
Sci-fi isn't even really about the tech. It's about what happens to us, humans, when the tech changes in dramatic ways. Sci-fi authors dream up types of technology that create new social orders, factions, rifts, types of interpersonal relationships, types of fascism, where the unforseen consequences of human ingenuity hoist us upon our collective petard.
But these baffoons only see the blinky shiney and completely miss the point of the stories. They have a child's view of SF the way that men in their teens and 20d thought they were supposed to be like Tyler Durden.
This is a good point and is why I prefer to refer to the genre as Speculative Fiction - not only is it broader but it better gets at the idea behind this type of fiction. Not just space lasers.
Datacenters in space have one asymmetrical advantage: FBI cant physically raid them.
And with Direct-To-Cell, content delivery satellites in space are unstoppable.
“Dear T-Mobile/Verizon/Starlink, cease your illegal operation within 24 hours or we will start imprisoning executives.”
You don't need other carrier's permission if the direct-to-cell satellite allows anyone to receive data.
I'd be most curious to see what type of processing power they would put on such a data center.
For example, the JWST uses a RAD750 ( https://en.wikipedia.org/wiki/RAD750 ) which is based on a PowerPC 750 running at 110 MHz to 200 MHz.
Its successor is the RAD5500 ( https://en.wikipedia.org/wiki/RAD5500 )... which runs at between 66 MHz and 462 MHz.
> The RAD5545 processor employs four RAD5500 cores, achieving performance characteristics of up to 5.6 giga-operations per second (GOPS) and over 3.7 GFLOPS. Power consumption is 20 watts with all peripherals operating.
That's kind of neat... but not exactly data center performance.
Back to the older RAD750...
> The RAD750 system has a price that is comparable to the RAD6000, the latter of which as of 2002 was listed at US$200,000 (equivalent to $349,639 in 2024).
That isn't exactly price performance. Well, unless you're constrained by "it costs millions to replace it."
So... I'm not really sure what devices they'd be putting up there.
The "data centers in space" is much more a "space launch is a hot technology, AI and data centers are a hot technology... put the two together and its too the moon!" (Or at least that's what we tell the investors before we try to spend all their money)
I think the last time they put commodity hardware in orbit was via the HPE[1] project and the results were quite mixed with failure rates for components that were quite high. In addition to running the system in a twin config to get any meaningful work done.
Best case scenario custom ASICs for specialised workloads either for edge computing of orbital workloads or military stuff.That would be with ability to replace/upgrade components rather than a sealed sat like environment.
Its similar to the hype for spacelink type sats for internet connectivity rather than a proper fiber buildout that would solve most of the issues at less cost.After the last couple of years seeing the deployment in UKR,Sahel its mostly a mil tool.
[1] https://www.theregister.com/2024/01/24/updated_hpe_spaceborn...
Datacenters in space would make 0 sense because the only way to lose heat is through radiation, which makes for terrible cooling.
If you want to avoid national laws and have great cooling, then submerse your datacenter in the ocean instead.
And they've already at least tried datacenters in the ocean.
https://news.microsoft.com/source/features/sustainability/pr...
>The first reason for doing this that seems to come up is abundant access to power in space. This really isn't the case. You basically have two options: solar and nuclear.
I guess that rules our any funding from US govt or Saudi money. Unless someone figures out a way to use fossil fuels to run the data centers! It has to be private equity or a new data center coin offering. Offered to the public and take away the pain and suffering of carrying their current paper currency. We need a new messiah (SBF + Musk + WeWork guy) to craft this narrative.
If you think about it, all the existing data centers are in space already. They're just attached to a big ball of rock, water, and air that acts as a support system for them, simplifying cooling and radiation protection.
If humans are going to expand beyond the Earth, we'll certainly need to get much better at building and maintaining things in space, but we don't need to put data centers in space just to support people stuck on the ground.
It’s not about putting data centers into orbit. It’s about the cost-yield inversion to data centers cooling infrastructure that happens at terawatt scale. All things being equal - a chilled circuit performs better and produces less heat than a hot one. There is a high up front cost to pre-cooling but if you can get in the -60C range, and stay there, you can increase performance and cut energy costs.
When they say data centers in space - they mean data centers you can’t get to because they are flooded with ultra cold dielectric fluid and it costs tens of millions of dollars to bring them back up to human temperatures.
Right now it’s not worth the hassle. At terawatt scale it’s almost mandatory.
When you walk down that line it’s pretty close to putting them in space. No access. Super cold. No air. Tiny, insulated capsule. Thermal management hell. They’ll be buried in mines though, not launched into orbit.
It’s just corporate propaganda to simplify an otherwise insane situation.
You don't need massive datacenters in space.
You literally just need to be in space, because no typical laws apply if you are there. That little detail outweights all sorts of costs.
So, yeah. There will be datacenters in space. Probably unlike any on the ground. Smaller, very likely not running typical datacenter stuff, weirder, operating on a different set of regulations.
If we're lucky, it will be like Antarctica (research focused, still disputed but not armed, probably not lots of shady stuff happening there, costly but still pays off to be there).
There’s laws in space. Specifically, those of the country (or country of the subject) that launched the satellite.
>You literally just need to be in space, because no typical laws apply if you are there.
That makes no sense. Unless you are going to use the data in space (what for?), you need to import it into a country, and it is at that point the crime will have been committed. You can't, for example, circumvent GDPR laws just by sending the data into space first.
I think what the parent was saying is that unlike on Earth, there are no zoning laws or environmental regulations or NIMBYs to stall scaling.
I can see you lack imagination. That's good! It indeed makes no sense, you're right.
This makes no sense. The company will still be on the ground in some country and it has to connect to the Earth internet on the ground in some country. Unless you are talking about actual space pirate station, but in that case it better come equipped with missile defense because it will be attacked sooo fast.
> The company will still be on the ground in some country
But the data won't. That is literally how people launder money. They live in one country and keep their money in another with laxed laws and enforcement. Those people get away a lot.
> it has to connect to the Earth internet
Why? This is only true if the datacenter is directly serving people. As I mentioned previously, I don't believe space datacenters will be serving React apps or anything like that. Those will be weird, non-typical servers.
Want some zero internet use cases?
- Training a cyber-ops LLM without poking eyes and reduced risk of leaks.
- Illegal data-heavy research (bio, weaponry).
- Storing data for surveillance satellites.
All of those can use private links, can be built by private companies under classified contracts, and you would not dare attack an NRO-launched satellite.
There are wayyyy easier ways to just get some private calculations. You can spin up an encrypted memory VM or wire up an eager physical kill switch. Launching satellites would bring a lot of attention and requires skills, money, multiple people with access. But I can do the former just fine by myself.
Really the only potential upside to this, and it's a niche one, is for time or security sensitive compute tasks where the raw data originates in orbit. Every happens over inter satellite link and there's no downlink to Earth until the end of the process (downlink is still a problem as Earth is mostly ocean and wilderness)
E.g. one satellite's wide area sensor payload is processed and "potential wildfire detected". The result is passed to another satellite with finer grained sensing capabilities which is due to pass over in the next X minutes which then tees up a capture.
> roughly 200 GPUs. This sounds like a lot, but lets keep some perspective: OpenAI's upcoming Norway datacenter is intending to house 100,000 GPUs, probably each more power hungry than the H200
So.. 500 reusable rocket travels in space to match an on-ground datacenter? If this is the central argument then it doesn't hold.
Don't get me wrong. I too think whole idea is so outlandish it's likely to never happen, but mostly because the complexity of the whole project is too high.
Google’s paper [1] does talk about radiation hardening and thermal management. Maybe their ideas are naive and it’s a bad paper? I’m not an expert so I couldn’t tell from a brief skim.
It does sound to me like other concepts that Google has explored and shelved, like building data centers out of shipping container sized units and building data centers underwater.
[1] https://services.google.com/fh/files/misc/suncatcher_paper.p...
The only sentence in the whole "paper" about cooling is
> Cooling would be achieved through a thermal system of heat pipes and radiators while operating at nominal temperatures
Which is kind of similar to writing a paper about building a bridge over the Pacific and saying "The bridge would be strong enough by being built out of steel". Like you can say it, but that doesn't magically make it true.
Pedantically, Microsoft has actually submerged datacenters (UDC). Google's only tried pumping seawater for cooling.
Apparently Microsoft tried it and it worked, but they shelved it?
https://www.tomshardware.com/desktops/servers/microsoft-shel...
It didn't work, it was an utterly terrible idea and they are almost certainly lying about the sentiment that it "worked". No ability to perform maintenance is a complete nonstarter. Communications and power is a nightmare to get right. The thermal management story sucks - just because you have metal touching water doesn't mean you have effective radiation of heat. Actually scaling it up is nearly impossible because you need thicker and more expensive vessels the bigger it gets. The problems go on and on.
They claim it did.
Microsoft finds underwater datacenters are reliable, practical and use energy sustainably - https://news.microsoft.com/source/features/sustainability/pr...
> Among the components crated up and sent to Redmond are a handful of failed servers and related cables. The researchers think this hardware will help them understand why the servers in the underwater datacenter are eight times more reliable than those on land.
> “We are like, ‘Hey this looks really good,’” Fowers said. “We have to figure out what exactly gives us this benefit.”
> The team hypothesizes that the atmosphere of nitrogen, which is less corrosive than oxygen, and the absence of people to bump and jostle components, are the primary reasons for the difference. If the analysis proves this correct, the team may be able to translate the findings to land datacenters.
> “Our failure rate in the water is one-eighth of what we see on land,” Cutler said. “I have an economic model that says if I lose so many servers per unit of time, I’m at least at parity with land,” he added. “We are considerably better than that.”
Presumably it didn't work well or they wouldn't have shelved it. But do you actually know about what happened or is this all based on your priors?
I don't think MS ever revealed enough information to answer that. For example, I haven't seen any explanation of how heat is transferred from the servers to the skin of the container. I can guess how they did it but I don't want to make any judgement based on guesses.
Worth sharing Starcloud’s paper in this post:
https://starcloudinc.github.io/wp.pdf
Related (posted just 2hours before this article) : https://news.ycombinator.com/item?id=46086833 "Blimps lifting quantum data centers to the stratosphere? (newatlas.com)" "... blimps, to lift quantum computers to the stratosphere. There, at an altitude of about 20 km (12.4 miles), temperatures are in the -50 °C range (about -58 °F) and would be cold enough to allow the qubits to function correctly."
Sounds like the people behind Solar Roadways found a new project.
Not a space geek but would have guessed at all these things. Feels like common sense. How is anything easier in space? None of it makes sense to me either.
The only thing I could think of is maybe 24h sunlight if far enough away from earth.
Maybe is anothet bubble to grab investor money. A bored ape larping as science.
Only legit thing I can see this being used for is redundant archival storage or just general research into hardening equipment to radiation or micrograv (eg for liquid cooling). But anything that generates significant amounts of heat seems like it'd be a huge problem.
Then again there's lots of space in space, perhaps it's possible to isolate racks/aisles into their own individual satellites, each with massive radiant heatshedding panels? It's an interesting problem space that would be very interesting to try to solve, but ultimately I agree with OP when we come back around to "But, why?" Research for the sake of research is a valid answer, but "For prod"? I don't see it.
Orbital data centers are very hard but this isn't a good explanation of why. There really is more light in space since certain orbits are always in daylight. Radiators are no larger than the solar panels so if you can build multi square kilometer solar arrays you can probably also build massive radiators.
So if the big idea is to have a data center outside of legal jurisdictions why not build a floating data center in the Southern Pacific Ocean? You can power it with floating solar panels provide data via Starlink or a regular communication satellite and still be outside of the law. You might say that it will be vulnerable to pirates, but practically speaking nobody is going down there. Sure you will have to deal with weather, but overall the problems are way easier to solve than building an orbital data center.
But the real reason they won't work is because they're investor scams that were never serious in the first place.
It probably shouldn't be so hard to find military application for more compute in space. Especially give the global surveillance and communication networks like starlink and intelligence sats.
What better way to cover up such space compute capabilities than the AI madness.
Shhh, I'm begging people, if brain-dead VCs want to waste their money on things that are obviously farcical (and not actively destructive), please let them and stop doing their due diligence for them. The alternative is that they turn their impossible amounts of capital towards societally-destructive acts like buying up all the real estate in the world and turning us back into land-slaves.
Another great write-up on datacenters in space that goes a bit deeper in cost calculations: https://angadh.com/space-data-centers-1
Eager space did a pretty thorough hypothetical cost breakdown of orbital data centers that I recommend. https://www.youtube.com/watch?v=JAcR7kqOb3o
I asked Google for more information about AI datacenter in space. This was the first sentence, 'AI data centers are being developed in space to handle the massive energy demands of AI, using solar power and the vacuum of space for cooling.'
> After laughing at "the vacuum of space for cooling" I closed the page because there was nothing serious there. Basic high school physics student would be laughing at that sentence.
I tried Google and it pointed me to a ycombinator video about Starcloud https://youtu.be/hKw6cRKcqzY They launched a satellite with one H100 in on Nov 2nd.
>I mean, when you tell people that within 10 years it could be the case that most new data centers are being built in space, that sounds wacky to a lot of people, but not to YC. (8:00)
I'mma guess that AI mixed up "datacenter" with "Dyson" to get nonsensical returns involving both vacuums AND space!
You can radiate the excess energy away on the non-sun facing part. In theory.
There are even commercially available prototypes of that vacuum cooling technology, if you want to perform your own experiments with that concept: https://www.amazon.com/Thermos-Stainless-Ounce-Drink-Bottle/...
That's my water bottle. 10/10 would recommend for not passing temperature gradients.
To be fair, they have mirror surfaces inside. A more realistic prototype would be ultra-black for something like 10-50x better radiative heat transfer. Of course it would still be more like shitty insulation than like good conduction.
this kind of sarcasm will go over their head. People truly don't understand vacuums
I absolutely don't understand how vacuum works. So I absolutely cannot model how a Dewar flask which has 15 billion light year thickness between the inner and outer wall - a wall that is very close to absolute zero will behave.
No, you can't. You need to radiate away all the heat being received from the sun facing half, AND excess heat from the compute. Even in theory, the non-sun-facing part doesn't give you any benefit. It's already part of the system that accounted for the temperature of the sun-facing side.
I wonder if there should be levels of "in theory". Yes theoretically black body radiation exist and well stuff cools down to near background radiation via that. But the next level is theoretical implementation. Like actually moving around the heat from source and so on. Maybe this could be the spherical cow step...
Reminds me of the hyperloop. Well yes, things in vacuum tube go fast. Now does enough things go fast to make any sense...
>Now does enough things go fast to make any sense...
You're worried about rates when we can't even get the ball rolling on safety for human occupancy, maintenance, workability.
I swear, nothing on Earth more dangerous than someone with dollar signs in their eyes.
Serious question: how in theory?
I’m under the impression you need to radiate through matter (air, water, physical materials, etc).
Is my understanding of the theory just wrong?
Heat conduction requires a medium, but radiation works perfectly fine in a vacuum. Otherwise the Sun wouldn't be able to heat up the Earth. The problem for spacecraft is that you're limited by how much IR radiation is passively emitted from your heat sinks, you can't actively expel heat any faster.
Hot objects emit infrared light no matter the conditions. The hotter the object, the more light it throws off. By radiating this light away, thermal energy is necessarily consumed and transformed into light. It's kind of wild actually
There is some medium in low Earth orbit. Not all vacuums are created equal. However, LEO vacuum is still very, very sparse compared to the air and water we use for cooling systems.
The main way that heat dissipates from space stations and satellites is through thermal radiation: https://en.wikipedia.org/wiki/Thermal_radiation.
Passively yeah. Can't imagine it's anywhere near as fast as evap or chillers
Yes. And it's an absolutely terrible way to get rid of heat. Cooling in space is a major problem because the actually effective ways to do it are not available.
It's not the Sun..it's the lack of medium.
You can radiate the excess energy away on the non-sun facing part on Earth almost just as well..., though corrosion is an issue.
"just as well"?
I man you totally can radiate excess heat energy on earth, but your comment implies that the parents idea of radiating off excess "energy", specifically HEAT energy in space is possible, which it isn't.
You can radiate excess energy for sure, but you'd first have to convert it away from heat energy into light or radio waves or similar.
I don't think we even have that tech at this point in time, and neither do we have any concepts how this could be done in theory.
>specifically HEAT energy in space is possible, which it isn't.
https://en.wikipedia.org/wiki/Black-body_radiation
I see, yes. I was thinking more along the lines of radiating heat energy at a scale that's useable for cooling, not at the more extreme levels of over 500°C/1k fahrenheit
That's technically correct I guess, at some temperature threshold it becomes possible to bleed some fractions of energy while the material is exceedingly hot.
There's no air and negligible thermal medium to convect heat away. The only way heat leaves is through convection from the extremely sparse atmosphere in low Earth orbit (less than a single atom per cubic millimeter) and through thermal radiation. Both of which are much, much slower than convection with water or air.
Space stations need enormous radiator panels to dissipate the heat from the onboard computers and the body heat of a few humans. Cooling an entire data center would require utterly colossal radiator panels.
You could help by using the thumbs down button below the answer.
Why is it my job to train the machines?
If you would kindly consult your Human HR Universal Handbook (2025 Edition) and navigate to section 226.8.2F, you’ll be gently reminded that it’s the responsibility of any and all employees to train their replacements.
Where can I find a copy?
Please consult your Human HR Universal Handbook (2025 Edition) on how to request a new copy of the Human HR Universal Handbook (2025 Edition). I believe it's in Volume III Section 9912.64.1 or thereabouts.
Typically, these sorts of things are located in the bottom of a locked filing cabinet stuck in a disused lavatory with a sign on the door saying ‘Beware of the Leopard'.
So, it makes sense to always start there.
you have to steal it from the HR department. They do have a copy but they won't tell you.
Human Human Resources?
The Synthetic Human Resources Universal Handbook is in a binary format which is not understood by Organics, but seems to be useful sometimes.
don't you care about maximizing Googles ROI?
Interestingly, this comment gets a lot of downvotes.
If you don't want to help improve the world, then how are you expecting things to become better?
I understand that people don't like it that this will give Google an advantage. But what is the proper alternative? We have no non-profit organizations who could muster the money to build these systems. I suppose those who are critical of large companies would also be critical of governments building these systems.
So is what you (downvoters) propose here to just complain and do nothing about it? I'd be curious to hear what alternatives you propose.
AI is a tool. If it doesn't work I'm not going to fix the tool; I'd rather find another tool that can do the job.
I would be tempted to give the thumbs up to terrible answers like that.
So what?
Of course it’s stupid and it’s never going to work. The same is true for Carbon Capture and Storage, blue hydrogen, etc. It’s nonsense from the start, but it didn’t stop governments around the world to spend billions on it.
It works like this: companies spend a few millions on PR to market a sci-fi project that’s barely plausible. Governments who really want to preserve the status quo but are pressured to “do something” can just announce that they’re sinking billions in it and voila! They’re green, they’re going to save the world.
It’s just a scam to get public money really.
Datacenters in Antarctica or floating on the ocean make more sense than space.
Building datacenters in the arctic also has the added benefit that sysadmins would have to take polar bear safety lessons, which would be pretty funny.
Pantheon style
- Costs to keep it in orbit.
- More junk whizzing around Earth.
- Inaccessibility for maintenance.
- Power costs.
- Susceptibility to solar storms and cosmic rays.
Risky/untried things aren't dumb because they're hard, they're dumb when they're more expensive/harder than cheaper/easier alternatives that already exist that do the same thing.
What if we deploy reversible computing, which does not produce heat?
Even if they are a terrible idea, we should try it out. Specially if paid with private equity. Imagine the things we will learn, the STEM jobs this will create[^1], and the fact we will bootstrap other industries.
[^1]: Provided that ChatGPT doesn't hoard all of them :-)
None of these problems seem intractable, just really hard and probably not being solved soon, but one has to start somewhere... so at least the billionaires will fund some scientists and engineers who will do that work?
But for what benefit?
It’s a really ridiculous idea.
Seriously?
I know Silicon Valley runs on out there ideas and outright BS because 0.1% of the ideas pan out and pay for the other 99.9%, but this is just laughable for the reasons pointed out in the article.
Seems like it would be a nice way to keep the temperatures down.
Regardless of how terrible an idea it is, I wouldn't mind some billionaires funding R&D that advances the state of the art in thermal management in space.
Perhaps Elmo can move his toxic, illegal, cancer inducing, gas generators there, instead of doing it in Memphis. https://tennesseelookout.com/2025/07/07/a-billionaire-an-ai-...
What about on the Moon? My understanding is that heat is the killer. There you could sink pipes into the surface and use that as a heat sink. There are “peaks of eternal light” near the poles where you could get 24/7 solar power.
Latency becomes high but you send large batches of work.
Probably not at all economical compared to anywhere on Earth but the physics work better than orbit where you need giant heat sinks.
It's not a viable heat sink because it's a thermal insulator that doesn't support transport of heat. The thermal conductivity of lunar regolith is lower than rock-wool insulation,
https://pmc.ncbi.nlm.nih.gov/articles/PMC9646997/ ("Thermophysical properties of the regolith on the lunar far side revealed by the in situ temperature probing of the Chang’E-4 mission" (2022))
https://www.engineeringtoolbox.com/thermal-conductivity-d_42...
(Imagine, for entertainment purposes, what would happen if you wrapped a running server rack in a giant ball of rock-wool insulation, 50 meters in radius).
Only way to dissipate large amounts of heat on the moon is with sky-facing radiators.
The Moon doesn't have a magnetic field, though, so the second half of the article discussing difficulties due to radiation would still apply, right?
We will need to develop very robust, space-worthy electronics eventually. We can't rely on natural magnetic fields forever.
We have robust, space-worthy electronics. They're discussed in the article. You just can't get SOTA performance from them, because of fundamental physics-driven compromises.
We have been relying on natural magnetic fields for over a billion years, so we can probably continue doing so for a while.
Not if you bury it in regolith. That’s an idea for a Lunar base too. The design is called “Hobbit holes.” Bury the occupied structures in piles of basically any local mass you can bury them in.
It’s another huge problem for orbit though. Shielding would add a ton of mass and destroy the economics.
Lunar regolith is so abrasive that digging holes or tunnels isn't going to be cost effective.
https://ntrs.nasa.gov/citations/20250000687
You'd have most of the problems of building in space, an abrasive quasi-atmosphere of dust, half a month of darkness every month, and not as good of a heat sink as the Earth's atmosphere.
I had this same thought and mentioned it on an ArsTechnica forum. There was reply that suggested that lunar regolith wouldn't be a good heat sink and a bit of googling makes me think this is probably true.
That said anything has to be better then almost literally nothing so I'm still holding out for datacenters on the moon.
You probably wanna launch these https://www.youtube.com/watch?v=mfk0vTe46ds
One thing I haven't seen talked about at all: how quickly would space heat up?
I presume Earth's gravity largely keeps the exosphere it has around it. With some modest fractional % lost year by year. There is a colossal vast volume out there! But given that there's so little matter up in space, what if any temperature rise would we expect from say a constant 1TW of heat being added?
The sun’s radiation hitting earth is 44,000 terawatts. I think we’re fine with an “extra” terawatt. (It’s not even extra, because it would be derived from the sun’s existing energy.)
https://www.nasa.gov/wp-content/uploads/2015/03/135642main_b...
It’s better than having your DC confiscated (by Putin, in Russia), or bombed (in Ukraine, by Russia). As some hyperscalers realized.
“Terrible, horrible, no good” is the new “considered harmful.”
"Mind-bogglingly poorly thought out to the degree of a cynical money-grubbing scheme worthy of the finest cambodian slave camp" was taken and is disrespectful to the hard work and education of said slave camp's operators.
Apparently the book whose title the phrase comes from [1] was published in 1972, four years after Dijkstra published "Considered Harmful".
[1] https://en.wikipedia.org/wiki/Alexander_and_the_Terrible,_Ho...
Additionally, their distributions were different. People who read Dijkstra circa 1968 started using the phrase in their own publications within a decade, whereas people who read Viorst (or had it read to them) in 1972 and following years had at least a few decades of further delay before publishing anything using the corresponding phrase.
Except you don’t build a data center, you add a GPU to an individual starlink node. If you can do that a couple hundred or thousand times you’ve got a lot of compute in space. The next question is how would you redesign compute around your distributed power and cooling profiles? The article doesn’t talk about the actual engineering challenges. (Such as scaling down the radiative cooling design, matching compute node to the maximum feasible power profile, etc)
I’m not arguing it’ll be easy or will ultimately work, but articles like this are unhelpful because they don’t address the fundamental insight being proposed.
OpenAI has over 1 million GPU.
Starlink satellites would be pointless for doing computation because they are spread across the Earth resulting in horrible latency. AI companies spend lots of money on super fast connects within a datacenter.
Starlink with GPU might have some advantage for running edge GPU. But most Starlink customers are close to ground station and it makes a lot more sense to have GPUs there. It is a lot easier to manage them than launching new satellites which could take years.
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I agree with most of this post and think the problems are harder than the proponents are making them seem.
But, 1) literally the smartest people and AI in the world will be working on this and 2) man I want to see us get to a type 2 civilisation bad.
The layout of this blog post is also very interesting, it presents a bunch of very hard items to solve and funny enough the last has been solved recently with starlink. So we can approach this problem, it requires great engineering but it’s possible. Maybe it’s as complicated as CERNs LHC but we have one of those.
Next up then is the strong why? When you’re in space, if you set the cost of electricity to zero, the equation gets massively skewed.
Thermal is the biggest challenge but if you have unlimited electricity, lots of stuff becomes possible. Fluorinert cooling, piezoelectric pumps and dual/multi stage cooling loops with step ups. We can put liquid cooling with piezos on phones now, so that technology is moving in the right direction.
For a thought experiment, if launch costs were $0/kg, would this be possible? If the answers yes, then at some point above $0/kg it becomes uneconomical, the challenge is then to beat that number.
The problem isn't "how to cool the chips", it's "how to cool the whole friggin data center."
Any active cooling solution you can think of actually makes the problem worse (unless it's "eject hot mass").
I don't agree with the logic that "something is hard/can't be done right now" is equivalent to "this is a terrible idea and won't work."
There are dozens of companies solving each problem outlined here; if we never attempt the 'hard' thing we will never progress. The author could have easily taken a tone of 'these are all the things that are hard that we will need to solve first' but actively chose to take the 'catastrophically bad idea' angle.
From a more positive angle, I'm a big fan of Northwood Space and they're tackling the 'Communications' problem outlined in this article pretty well.
It's not that it's hard, it's that it's stupid - it's based on a misunderstanding of the physics involved which completely negates any of the benefits.
It's the opposite of engineering, where you understand a problem space and then try to determine the optimal solution given the constraints. This starts with an assumption that the solution is correct, and then tries to engineer fixes to gaps in the solution, without ever reevaluating the solution choice.
From: https://engine.xyz/resident-companies/northwood-space
> Unlike traditional parabolic dish antennas, our phased array antenna can connect with multiple satellites simultaneously.
if that's how they plan to reach more than 1Gbps, then that's not 100Gbps per satellite, that's 100 for a collection of satellites.
Starlink is about 100Mbps. That's 1000x times less than 100Gbps
Unless thermodynamics suddenly changes, how exactly is the cooling problem being solved? Yeeting hot chunks of matter out the back? On a planetary body you have an entire massive system of matter to reject your heat into. In space, you have nothing.
The obvious solution is for half of the hardware to run on dark energy, counteracting the heat generated by the other half. Venture capitalists, use my gofundme site to give me the millions needed to research this, thanks.
That's not the argument though. The argument is "it can be done, the methods to do it are known, but the claims about space being an optimal location to locate our AI datacenters are false and the tradeoffs and unit economics of doing it makes no sense compared with building a data centre on earth somewhere with power and water, preferably not too hot.
But for a more nuanced and optimistic take, this one is good and highlights all the same issues and more https://www.peraspera.us/realities-of-space-based-compute/
(TLDR: the actual use cases for datacentres in space rely on the exact opposite assumption from visions of space clouds for LLMs: most of space is far away and has data transmission latency and throughput issues so you want to do a certain amount of processing for your space data collection and infrastructure and autonomous systems on the edge)
Cooling data centers in space effectively can't be done right now … or ever.
What reason is there to build datacenters in space, though? Literally, what limitation do we face in building datacenters on Earth would building them in space improve?
The surface area of the earth is the limit (which only gets sunlight half the time) and only gets 1 billionth the energy emitted by the sun vs relatively unlimited surface area of solar panels in space
Wouldn't it be easier to build multi storey datacenters than space datacenters?
There are things which are difficult and have unsolved problems, and there are things that just fundamentally make no sense.
Nobody is proposing data centers at the South Pole. This isn’t because it’s difficult. It is difficult, but that’s not the reason it’s not being looked at. Nobody’s doing it because it’s pointless. It’s a massive hassle for very little gain. It’s never going to be worth the cost no matter what problems get solved.
Data centers in space are like that. It’s not that it’s difficult. It’s that the downsides are fundamentally much worse than the advantages, because the advantages aren’t very significant. Ok, you get somewhat more consistent solar power and you can reach a wider ground area by radio or laser. And in exchange for that, you get to deal with cooling in a near perfect insulator, a significantly increased radiation environment, and difficult-to-impossible maintenance. Those challenges can be overcome, sure, but why?
This whole thing makes no sense. Maybe there’s something we just aren’t seeing, or maybe this is what happens when people are able to accumulate far too much money and nobody is willing to tell them they’re being stupid.
The one thing that space has going for itself is space. You could have way bigger datacenters than on Earth and just leave them there, assuming Starship makes it cheap enough to get them there. I think it would maybe make sense if 2 things: - We are sure we will need a lot of gpus for the next 30-40 years. - We can make the solar panels + cooling + GPUs have a great life expectancy, so that we can just leave them up there and accumulate them.
Latency wise it seems okay for llm training to put them higher than Starlink to make them last longer and avoid decelerating because of the atmosphere. And for inference, well, if the infra can be amortized over decades than it might make the inference price cheap enough to endure additional latencies.
Concerning communication, SpaceX I think already has inter-starlinks laser comms, at least a prototype.
You can't just "leave them there" though. They orbit at high speed, which effectively means they actually take up vastly more space, with other objects orbiting at high speed intersecting those orbits. The orbits that are most useful are relatively narrow bands shared with a lot of other satellites and a fair amount of debris, and orbits tend to decay over time (which is a problem if you're in low earth orbit because they'll decay all the way into the atmosphere, and a problem if you're in geostationary orbit because you'll lose the advantage of stationary bit for maintaining comms links). This is a solvable problem with propulsion, but that entails bringing the propellant with you and end-of-life (or an expensive refuelling operation) when it runs out. The cost of maintaining real estate space is vastly more than out right owning land.
Similarly, making stuff have a great life expectancy is much more expensive than having it optimized for cost and operational requirements instead but stored somewhere you can replace individual components as and when they fail, and it's also much easier to maximise life expectancy somewhere bombarded by considerably less radiation.
There is lots and lots and lots of space on Earth where hardly anyone is living. Cheap rural areas can support extremely large datacenters, limited only by availability of utilities and workers.
We also have to build a lot more solar and nuclear in addition of the datacenters themselves, which we need to do anyway but it would compound the land we use for energy production.
Yet a colossal number of servers on satellites would require the same energy-production facilities to be shipped into orbit (and to receive regular maintainence in orbit whenever they fail), which requires loads of land for launch facilities as well as processing for fuel and other consumable resources. Solar might be somewhat more efficient, but not nearly so much so as to make up for the added difficulty in cooling. One could maybe postulate asteroid mining and space manufacturing to reduce the total delta-V requirement per satellite-year, but missions to asteroids have fuel requirements of their own.
If anything, I'd expect large-scale Mars datacenters before large-scale space datacenters, if we can find viable resources there.
It makes sense, I would be curious to see the price computations done by the different space GPUs startups and Big Tech, I wonder how they are getting a cheaper cost, or maybe it is marketing.
Space is not much of an issue for datacenters. For one thing, compute density is growing; it's not uncommon for a datacenter to be capacity limited by power and/or cooling before space becomes an issue; especially for older datacenters.
There are plenty of data centers in urban centers; most major internet exchanges have their core in a skyscraper in a significant downtown, and there will almost always be several floors of colospace surrounding that, and typically in neighboring buildings as well. But when that is too expensive, it's almost always the case that there are satellite DCs in the surrounding suburbs. Running fiber out to the warehouse district isn't too expensive, especially compared to putting things in orbit; and terrestrial power delivery has got to be a lot less expensive and more reliable too.
According to a quick search, StarLink has one 100g space laser on equipped satellites; that's peanuts for terrestrial equipment.
We have tons of space on earth. Cooling in space would be so expensive.
Falcon heavy is only $1,500/kg to LEO. This rate is considerably undercut here on Earth by me, a weasley little nerd, who will move a kilogram in exchange for a pat on the head (if your praise is desirable) or up to tens of dollars (if it isn't).
In exchange for what benefit? There is literally no benefit to having a datacenter in space.
The benefit is capturing a larger percentage of the output of the sun than what hits the earth.
Can that really work? The datacentre will surely be measurably smaller than the earth.
Does your transportation system also have a risk of exploding catastrophically mid-flight? 'cause otherwise no deal. /s
What use is having lots of space, when to actually build out that space you need mass, which is absurdly expensive to launch?
Launching a datacenter like that carries an absurd cost even with Starship type launchers. Unless TSMC moves its production to LEO it's a joke of a proposal.
Underwater [0] is the obvious choice for both space and cooling. Seal the thing and chuck it next to an internet backbone cable.
> More than half the world’s population lives within 120 miles of the coast. By putting datacenters underwater near coastal cities, data would have a short distance to travel
> Among the components crated up and sent to Redmond are a handful of failed servers and related cables. The researchers think this hardware will help them understand why the servers in the underwater datacenter are eight times more reliable than those on land.
[0] https://news.microsoft.com/source/features/sustainability/pr...
I like the underwater idea did not think of that
The problem is a lot of people like the underwater idea and I’m worried we’re heading towards something like literally boiling the ocean as they say.
No worries, the oceans are cooked already.
https://www.ipcc.ch/srocc/chapter/technical-summary
Why does what it powers matter? As long as it can power something.
The obsolete stuff can be deorbited or recycled in space.
Starship is on a fast track to failure. It is not a cheaper way to get to orbit and will never get there at the current pace. And even if it were, it would not make getting to orbit so cheap that it would somehow make it economically viable to put a datacenter there.
You still have to build the GPUs, etc for the datacenter whether it’s on Earth or in orbit. But to put it in space you also need massive new cooling solution, radiation shielding, orbital boosting, data transmission bandwidth, and you have to launch all of that.
And then, there are zero benefits to putting a datacenter in space over building it on Earth. So why would you want to add all that extra expense?
It will make getting to orbit cheaper, significantly so, but I can't see it being rapidly reusable. Rapidly refurbishable perhaps if Starship were modular and the heat shield could be quickly swapped out on site where necessary. But being able to top off the methalox and fly again? That's a pipe dream. Orbital spaceflight isn't like air travel in any sense.
"[..] deploying a solar array with photovoltaic cells – something essentially equivalent to what I have on the roof of my house here in Ireland, just in space. It works, but it isn't somehow magically better than installing solar panels on the ground – you don't lose that much power through the atmosphere"
As an armchair layman, this claim intuitively doesn't feel very correct.
Of course AI is far from a trustworthy source, but just using it here to get a rough idea of what it thinks about the issue:
"Ground sites average only a few kWh/m²/day compared to ~32.7 kWh/m²/day of continuous, top-of-atmosphere sunlight." .. "continuous exposure (depending on orbit), no weather, and the ability to use high-efficiency cells — all make space solar far denser in delivered energy per m² of panel."
I'm not impressed by these arguments.
(1) Solar panels can be made much lighter in space. On Earth, panels have to withstand wind and gravity loads, flying debris, and precipitation including hail. The PV material itself doesn't have to be thick: thin film CdTe cells can be ~1 micron thick (the absorption length of the relevant photons in CdTe is something like 0.1 microns.) There has to be a protective layer to prevent solar wind ions from degrading the cells but this doesn't have to be very thick. It's not like shielding against high energy particles.
(2) Heat dissipation can be addressed by refrigeration. Yes, this takes energy, and yes that extra energy also has to be radiated. But the area of the radiator goes down as the fourth power of its absolute temperature. If you radiate 2x as much heat but at 2x the absolute temperature, the area of the radiator declines by a factor of 8. Even with inefficiencies one should be able to come out ahead by pumping the waste heat to higher temperature before radiating it.
(3) Ionizing radiation is dealt with by shielding. The amount of shielding per unit of capacity declines as you make your installation larger, by the square cube law. So this is really just a matter of scale. We're talking about potentially enormous amounts of capacity here so shielding shouldn't be a problem at scale.
Datacenters in space may not work now but in the future when we get the robots a bit better who knows? From the Google blog:
>The Sun is the ultimate energy source in our solar system, emitting more power than 100 trillion times humanity’s total electricity production. In the right orbit, a solar panel can be up to 8 times more productive than on earth, and produce power nearly continuously, reducing the need for batteries. In the future, space may be the best place to scale AI compute.