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A bank run happens when everyone tries to withdraw all their money at the same time and the bank runs out of cash. Not really possible in the stock market where companies literally can create/destroy shares and there is a whole secondary pricing layer to it.
1. https://www.reuters.com/business/finance/alphabets-spacex-be...
I'm not sure that's truly the case here, but it does seem like the tech Project Suncatcher is working on has at least some overlap with requirements for military SIGINT and in-orbit imagery processing.
Both of those are expensive as hell, by the way.
Cooling via radiation follows Stefan–Boltzmann: P = εσAT⁴. Let's assume a good surface (emissivity ~0.9) at 300 K (27 °C) at 400 W per square meter per side. A flat panel radiating from both faces into deep space gets 800 W/m, not including the losses from, say, the Sun, or from IR coming off the Earth. Now, input power. Sunlight in orbit ~1,360 W/m², assume ~22% cell efficiency, we got 300 W/m². So each 1 MW compute, 3,300 m² of solar panel and minimum 1,200–1,500 m² of radiator.
In case ya didn't know - 1 MW is tiny from a present-day-datacenter perspective. It's like 8 racks. So we're talking orbital megastructures here, many many many square kilometers, and this is with all the best case assumptions, and magic radiator panels that never see the sun, or the earth, or the moon.
This is just the basic numbers here, by the way. There's a garbage truck full of other unsolvable problems if you poke your head in there.
Aside from the "Avoid Regulations" aspect, and the "Everything That Burns Deorbiting is Depreciation" aka "The Starlink Trick", I'm not sure what the hell the draw is.
For that you might need more advanced stuff like liquid droplet radiators (https://en.wikipedia.org/wiki/Liquid_droplet_radiator), heat sinks & pulsed operation. Still, it should be eventually doable.
As for space data centers - I think the main issue is the complete lack of in space infrastructure for resource mining, processing and manufacturing & maintenance. It is kinda like building your first practical steam locomotive & the deciding to build directly an airliner. No suitable materils, experience, work force, material sources, etc.
We eventually went from locomotives to airliner, in an incremental manner & expanding the supporting infrastructure to support the ever more ambitious projects.
We need > 2x more solar panels than we need radiators. Doesn't this imply radiation isn't really the limiting factor here?
That's thumping the Carnot limit: [[T_cold / (T_hot − T_cold)]].
2.5, while rejecting at 500 K, cold side's at least 357 K (eeehhhhhhh 84 °C) . . . and that's an absolutely perfect Carnot machine. At 50% Carnot -- a pretty good heat pump, real world performance is 40-60 -- cold side's at 417 K (144 °C). 417k, feeding your GPU coolant loops.
Though I do wonder if it would be possible to have some kind of internal heat pump driven by electrical power to juice up the temperature of the radiators to increase the power being radiated away? E.g., run a heat pump to increase the temperature of a working fluid and then run high temperature radiators? I think it would work and I don't immediately see that it would violate the laws of thermodynamics? (this is ignoring all practically, I'm sure the engineering would be devilishly hard, although if you're already shooting for the moon you might as well throw in some artificial gravity to boot, it's not like the robots get motion sickness)
Luckily, there are almost no rock in space.
one is marketing.
the other is that you could make tiny datacenters and flood the sky with them. in effect, not datacenters at all, but some kind of dataswarm coordinating at literal lightspeed via lasers.
they'd still be wildly expensive to deploy, and probably litter the orbit zone with fast-moving debris.
You want to go smaller and go one rack only sure, it's still hundreds of square meters. Check the size of current orbital structure for a point of reference, you can't dwarf those and call it a "dataswarm of tiny datacenters flooding the sky".
“ We’re working on a number of different approaches for this, including a combination of heat pipes and radiators to cool the chips. So far, our team has tested the technology in a thermal vacuum chamber that simulates both the thermal and vacuum environment in space. We’ll see how our new TPU cooling system works in space and refine our designs as we learn more.”
(I guess you could try to capture the radiative photons via the photoelectric effect?? but I don't think it works.)
TPU: 100,000+ watts/square-meter
Radiator: ~300 watts/square-meter
https://youtu.be/ktdbUIZKeSE?t=76
> The biggest challenge was how to cool the A.I. chips, which heat up when they perform calculations and process information. Fans, which typically help dissipate the heat, do not work in space. So the Silicon Valley company instead developed a cooling system that uses layers of conductive material to expel the heat into space.
> The bottom layer is made up of Google’s A.I. chips, which sit on a green motherboard. The next layer consists of “thermal interface material,” a pale green putty that comes in sheets like Fruit Roll-Ups and connects the chips to layers of aluminum and copper, radiating heat away from the motherboard. Finally, there is a radiator panel, which projects heat into space.
> The chips can operate for about 15 minutes in space before needing to be shut down so they can cool off, said Travis Beals, Google’s senior director of product management for Project Suncatcher.
I will take it as a given that the Google engineers know what they are doing, and their first version can only run for 15 minutes before it needs to shut down to cool.
*Profitability requiring that other Musk controlled companies do not pay for the service at elevated rates in a classic self dealing scheme.
Are you not aware that's exactly what SpaceX is doing?? https://www.spacex.com/spacexai/starmind Sure, it's now SpaceXAI or whatever, but how is that any different than Google sending up sats and selling the compute via Gemini?
You don't need civilian scale compute in space, but you absolutely can put miliary application up there and get filthy rich, like Elon, who doesn't care if it ever works, because he's getting paid as taxi service to shoot stuff up.
Sounds very probable: gives a plausible reasons for sending a lot of infra up, absolutely doesn't have to be profitable or even effective, puts the focus on AI instead of the MIC, and is in line with the kind of contracts Big Tech runs after.
To me this model explains a lot of why so many big companies seem to be investing into what every expert I've heard says goes against basic physics. The only thing missing for it to be more than an interesting idea is why China and the EU are not fighting this.
The only valid argument against data centers in space is the economic cost. If the per megatoken price for space datacenters is higher than terrestrial, then this won't work.
But the price for terrestrial datacenters keeps going up and technology keeps dropping the price of space-based.
If you are trying to generate a profit, every extra kg puts you further in the red. It still costs over $1000/kg of mass to get into orbit.
But if it's an economic argument, then you need to do the actual math. How big is the radiator? How low could the price to orbit go? How much can you charge per million tokens in 2030?
The reason this is a fake argument is because the validity depends on the math, and nobody advancing the "you can't cool stuff in space" argument is actually doing the math.
So... not easy? I don't suppose we're at a point where you could reasonably send a large-enough radiator for a multi-gigawatt cluster into space?
This is all a weird speedrun or race. If something we should be working on setting up resource mining from the Moon & asteroids, materials processing on the Lunar surface & in orbit, simple manufacturing in space, etc.
Instead some people think we can jump straight to a computronium Dyson swarm. :P
You don't need to send a multi-gigawatt satellite to space. You just need to launch a few thousand 250 kW satellites. That's not against the laws of physics.
Convective radiation does not happen in space and this challenge is far more significant than your comment implies. Rather than "a dumb hunk of metal", radiators for spacecraft are often made of ceramics and carbon laminates with higher IR emissivity than convective radiators made of simple metals.
From the article you're commenting on:
> The chips can operate for about 15 minutes in space before needing to be shut down so they can cool off, said Travis Beals, Google’s senior director of product management for Project Suncatcher.
The Thermal Control section on NASA's Small Spacecraft documentation center is quite an interesting read for this subject: https://www.nasa.gov/smallsat-institute/sst-soa/thermal-cont...
ML Infrastructure comes with some pros (larger emissive footprint) and cons (exponentially larger TDP) compared to the concerns there, but if you aren't familiar with the challenges of heat dissipation in space, please give it a read.
There's also a pretty interesting pop-sci article on cooling the Webb telescope, since it needs to be especially cold for its purpose. Not directly related, but may give insight into both challenges and solutions as well as well. https://science.nasa.gov/mission/webb/science-overview/scien...
The equation is:
Where P and T are the dominating factors. Don't worry about emissivity.If you know all that out to 2040 then you must be a time traveler. Please try to fix our timeline rather than wasting time on HN.
Moreover, you can easily calculate how big of a radiator you need for a given power level and temperature. You can use the Stefan–Boltzmann law:
Where For a 1 kW test like Googles, you just need 1 square meter of radiators (assuming two-sided).For SpaceX's 175 kW satellites, they will need ~170 square meters of radiators.
None of this is impossible or even difficult to calculate. That's why I think this is the laziest argument against space data centers. There are so many other more reasonable arguments (like whether they will be economically competitive) but people love to latch on to this one for some reason.
And they never will be because it's always going to be cheaper to build them on the ground.
Swapping out obsolete or failing TPUs. Rewiring or replacing connections. "Listening" for sounds indicating an equipment failure.
What are the proposals to address these needs?
> In the right orbit, a solar panel can be up to 8 times more productive than on earth....
1: There is no night or day.
2: There are no seasons.
3: There is no weather.
Basically, the primary motivating factor of putting AI in space is abundant solar energy. Otherwise, AI in space makes little to no economic sense.
The useful life of cutting edge AI server hardware will require constant rotation of equipment to potentially remain competitive with more accessible solutions.
Heat management ( https://m.youtube.com/watch?v=-w6G7VEwNq0 )
Hardening of equipment for the environment. ECC isn't going to be enough. I would have to defer to experts about the best way to manage it, but it either means custom hardware, weight, or both.
Repairs are impossible. Hopefully a sat can degrade gracefully, but routine repairs on earth become significant outages/decreases in economic value of a sat over time.
Rocket launches have gotten much better, but are not perfect. Insurance is a thing. However, cost of equipment in a failed launch may be eye watering, rivaling a governmental military launch.
* 24 hours of light vs. ~9 hours of light (e.g. winter)
* Panels perfectly perpendicular to sun 100% of the time vs. variable for fixed panels on earth
* No atmosphere
* No clouds
Either it's that weird "space is easier than getting land on earth"(it's not) or the same tortured arguments about heat dissipation, no one is going to run consumer scale compute with consumer scale economics in space ffs. And maintenance and cost does not matter when it comes to strategic military assets, they are a step function useful enough to warrant even a few monthly replacement.
Everyone else with strategic weapons and a space program e.g india china is launching one as well.
It's just far out research experiment like another commented quoted from the text: https://news.ycombinator.com/item?id=49834746
But even in this comment stream there are tons of people saying the cooling problem is insurmountable.
However, I do think avoiding local control (state/city permits) is a reason for this.
It’s very confusing to have a project related to space called a moonshot project.