https://starcloudinc.github.io/wp.pdf
huh? I was under the impression that cooling in space is an absolute nightmare since radiating heat into vacuum is super hard?
Even the comparatively small and decidedly H100-free ISS needed giant radiators
https://en.wikipedia.org/wiki/External_Active_Thermal_Contro...
Starcloud is developing a lightweight deployable radiator design with a very large area - by far the largest radiators deployed in space - radiating primarily towards deep space, which has an average temperature of about 2.7 Kelvin or -270°C. The radiators can be positioned in-line with the solar arrays as shown in Figure 3, with one side exposed to sunlight.
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Figure 3. A data center in Sun Synchronous Orbit, showing a 4km x 4km deployed solar array and radiators.
https://en.wikipedia.org/wiki/Spacecraft_thermal_control?wpr...
> Most spacecraft radiators reject between 100 and 350 W of internally generated electronics waste heat per square meter.
Radiative cooling works by exploiting the fact that hot objects emit electromagnetic radiation (glow), and hot means everything above absolute zero. The glow carries away energy which cools down the object. One complication is that each glowy object is also going to be absorbing glow from other objects. While the sun, earth, and moon all emit large amounts of glow (again, heat radiation), empty space is around 2.7 Kelvin, which is very cold and has little glow. So the radiative coolers typically need to have line of sight to empty space, which allows them to emit more energy than they absorb.
We should train AI in space [pdf] - >>41478241 - Sept 2024 (93 comments)
A bit more here:
Lumen Orbit - >>42790424 - Jan 2025 (2 comments)
VCs wanted to get into Lumen Orbit's $11M seed round - >>42518284 - Dec 2024 (2 comments)
> Their design calls for a cluster of shipping container-style boxes packed with high-speed AI chips. These would be anchored at the centre of a 16 sq km array of solar panels generating up to five gigawatts of power — about 25 per cent more than Drax, Britain’s biggest power station. The mammoth structure would circle the Earth in “sun synchronous” orbit so that it is never in shade
> As conduction and convection to the environment are not available in space, this means the data center will require radiators capable of radiatively dissipating gigawatts of thermal load. To achieve this, Starcloud is developing a lightweight deployable radiator design with a very large area - by far the largest radiators deployed in space - radiating primarily towards deep space...
They claim they can radiate "633.08 W / m^2". At that rate, they're looking at square kilometers of radiators to dissipate gigawatts of thermal load, perhaps hectares of radiators.
They also claim that they can "dramatically increase" heat dissipation with heat pumps.
So, there you have it: "all you have to do" is deploy a few hectares of radiators in space, combined with heat pumps that can dissipate gigawatts of thermal load with no maintenance at all over a lifetime of decades.
This seems like the sort of "not technically impossible" problem that can attract a large amount of VC funding, as VCs buy lottery tickets that the problem can be solved.
FWIW there's a reason that Sweden has a bunch of datacenters in the north that are peanuts compared to hosting in Virginia.
They're "poorly" connected (by virtue of being a bit out of the way), but the free cooling and power from renewables make them extremely attractive. There was a time where they were the favourite of crypto-miners for the same reason as they would be attractive to AI training farms.
Fortlax has some I believe; https://www.fortlax.se
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As for the meat of the paper. Anyone with a passing understanding of space will be quick to point out that:
A) Heat is a problem in space, it's either way-way-way to hot (IE; you're in the path of the Sun) or it's way-way-way too cold (IE; you're out of the sun) and the shift between the two means you need to build for both. You also can't dissipate heat as there's no air to take the heat away.
B) Power is not so abundant and solar panels degrade; a huge amount of satellite building is essentially managing a decline in the capability of hardware. That's part of why there are so many up there.
C) Getting reasonably sized hardware up there is beyond improbable, though I'll grant you that most of the weight in a computer is the cooling components and chassis.
D) Cosmic Rays. No electromagnetic barrier from earth and extremely tight lithographies. I mean... there's a reason NASA is still using CPU's measured in the megahertz range.
"Please don't fulminate."
"Don't be curmudgeonly. Thoughtful criticism is fine, but please don't be rigidly or generically negative."
This plan seems about as realistic as Bluthton though. https://www.reddit.com/r/arresteddevelopment/comments/1gtyvv...
https://www.youtube.com/watch?v=EsUBRd1O2dU
TL;DR... cooling in space isn't passive, you're on the "inside" of an enormous vacuum flask. And radiative coupling with space is possible from the ground, if that's what you're interested in:
https://www.skycoolsystems.com
But god bless crazy entrepreneurs. Don't ask whether we can, definitely don't ask if we should, just ask whether it makes for good headlines...
The whitepaper shows a 4km x 4km solar array, which is 1600 hectares (3200 International Space Stations). Would assume the array they're proposing would be cheaper since its structurally more homogenous, but $480 trillion dollars is a whole lot of money.
it's going to take the management of our shared resources and spaces (orbit) for instance to leave earth, and this becomes especially important as Kessler syndrome risk rises with increasing debris in orbit
private companies launching without public oversight and controls are a recipe for cluttering earth's orbit and leaving us earth-bound for far into the future (same if the public sector launches without care but that seems less likely imo)
Kessler Syndrome: https://en.wikipedia.org/wiki/Kessler_syndrome
> Additionally, deep space is cold, which is accurate in that the "effective" ambient temperature is around -270°C, corresponding to the temperature of the cosmic microwave background.
> he mass of radiation shielding scales linearly with the container surface area, whereas the compute per container scales with the volume
> Therefore the mass of shielding needed per compute unit decreases linearly with container size.
m = ρV.
Let's simplify and assume we're using a sphere since this is the most efficient, giving V = 4/3r^3. Your shield is going to be approximately constant density since you need to shield from all directions (can optimize by using other things in your system).
m ∝ ρr^3
I'm not sure what here is decreasing nor what is a linear relationship. To adjust this to a shell you just need to consider the thickness so you can do Δr = r_outer - r_inner and that doesn't take away the cubic relationship.
https://en.wikipedia.org/wiki/Thermal_radiation#Characterist...
https://en.wikipedia.org/wiki/Black-body_radiation
https://www.nasa.gov/smallsat-institute/sst-soa/thermal-cont...
https://ocw.mit.edu/courses/16-851-satellite-engineering-fal...
Seriously! There is just so much wrong and some of is trivial.
> radiating primarily towards deep space, which has an average temperature of about 2.7 Kelvin or -270°C.
In these locations you have to deal with cooling AND heating. On the moon you swing from -130C (LRO got down to -250C) on the dark side and 121C on the light side. The ISS swings from -160C to 120C. These are too cold for most electronics. Not to mention that these temperature swings create a lot of physical stress on parts, and we're talking about putting up up some of the smallest objects we commercially make? They will rip right off the circuit-board if you don't get it right.
Not to mention that radiating into space is quite difficult. There's a reason we use convection ovens and why we put fans in our computers. It isn't about the temperature of the atmosphere nor the thermal efficiency, it is because convection is just a hell of a lot more efficient. Thermal radiation is like shedding your heat via a lightbulb.
Their claim here is that they can radiate 633W/m2. For supercomputers we're talking on the order of 10s of MW of waste heat. That's 10^7! These are going to be BY FAR the largest radiators in space and going to cost tons of money for the mass alone.
Not to mention the size of the solar panels they'll need... But at least they mention this one: "A 5 GW data center would require a solar array with dimensions of approximately 4 km by 4 km," These are GIGANTIC structures and far larger than anything we've put into space.
> The mass of radiation shielding scales linearly with the container surface area, whereas the compute per container scales with the volume. Therefore the mass of shielding needed per compute unit decreases linearly with container size.
Density (ρ) is mass (m) divided by volume (V): m = ρV. We'll assume a sphere due to its efficient surface area. You use Δr as the shell's thickness: V = 4/3(Δr)^3
Let: m = ρV
Let: V = 4/3(Δr)^3
∴ m ∝ ρ(Δr)^3
> This effect, combined with the shielding afforded by the cooling blocks, means that radiation shielding is proportionally a much smaller concern compared to electronics on typical satellites today.
But also you have to remember that you can't shield your solar panels. To do so would prevent light from reaching them. That leads to a weird constraint here and I would not expect these machines to be meaningfully long lived. The alternative is you could go repair them, but that's expensive too.
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https://ocw.mit.edu/courses/16-851-satellite-engineering-fal...
https://www.jpl.nasa.gov/nmp/st8/tech/eaftc_tech1.php
https://www.nature.com/articles/s41597-024-03913-w
[0] I know this because I've research for NASA on radiation shields. I got multiple SBIR and STTR grants for this work. Material choices still do matter but the right material is proportional to the radiation level. But the higher the energy level, the less atomic properties matter and the more density does. You can get benefits from the electromagnetic properties of protons and electrons (beta-), but these don't help you with neutrons. That is, until after you slow these things down, which is why there is typically layering.
"Dr. Glaser is best known as the inventor of the Solar Power Satellite concept, which he first presented in the journal Science for November 22, 1968 (“Power from the Sun: It’s Future”). In 1973 he was granted a U.S. patent on the Solar Power Satellite to supply power from space for use on the Earth."
One thing that always struck me was that you wouldn't want to be living near the "collectors". A very small angular error in beaming could result in being literally microwaved.
https://www.youtube.com/watch?v=4CrTJEY8zNs
Such fun.
>Presumably the real purpose of this company is to refute people who said "We'll just walk over to the superintelligence and pull the plug out", without MIRI needing to argue with them
https://xcancel.com/ESYudkowsky/status/1831899029690839549#m
I can help explain why. On earth, we are surrounded by stuff. Radiative cooling relies on thermal radiation leaving an object. Crucially, it also requires the object to absorb less thermal radiation than it emits. On earth we are surrounded by stuff, including air, that emits thermal radiation. There is a window of wavelengths, called the atmospheric window[0], that will allow parts of the thermal radiation out into space, rather than returned back. Imagine shining a flashlight on tinted glass, the light will get through depending on the color. If the light gets through, it has escaped. If not, the light is returned and heats up your surroundings again.
Also on earth the other methods (conduction, convection, and phase changes) are more effective. The earth can be used as a very big heat sink. On a spaceship or satellite, you don't have the extra mass to store the energy, so radiative is the only option.