Comment by FloorEgg
9 hours ago
Setting aside the possibility it's window dressing for a financial bailout, there would be two ways compute in space makes sense:
1) new technology improves vacuum heat radiation efficiency
2) new technology reduces waste heat generation from compute
All the takes I've seen have been focused on #1, but I'm starting to wonder about #2... Specifically spintronics and photonic chips.
If you solve 2, heat dissipation goes away on earth too, so what’s the advantage of space
This is true for all of Elon's space ambition, fwiw.
I'm not the best person to make that case as I can only speculate (land cost, permitting, latency, etc). /Shrug
In all the conversations I've seen play out on hacker news about compute in space, what comes up every time is "it's unviable because cooling is so inefficient".
Which got me thinking, what if cooling needs dropped by orders of magnitude? Then I learned about photonic chips and spintronics.
If you're considering only viability, the obvious concern would be cooling, yes; because increasingly large radiative cooling systems dominate launch costs because of all the liquid you need to boost into orbit. And one 100MW installation would be 500 times the largest solar power/radiative cooling system we've ever launched, which is the ISS. So get that down 2 orders of magnitude and you're within the realm of something we _know_ is possible to do instead of something we can _speculate_ is possible.
After that frankly society-destabilizing miracle of inventing competitive photonic processing, your goal of operating data centers in space becomes a tractable economic problem:
Pros:
- You get a continuous 1.37 kW/m^2 instead of an intermittent 1.0 kW/m^2
- Any reasonable spatial volume is essentially zero-cost
Cons:
- Small latency disadvantage
- You have to launch all of your hardware into polar orbit
- On-site servicing becomes another economic problem
So it's totally reasonable to expect the conversation to revolve around cooling, because we know SpaceX can probably direct around $1T into converting methane into delta-V to make the economics work, but the cooling issue is the difference between maybe getting one DC up for that kind of money, or 100 DCs.
2 replies →
> space is called “space” for a reason.
you think we don't have enough space on earth for a few buildings? this seems like a purely western cope. China seems perfectly able to build out large infrastructure projects with a land area smaller than that of the continentenal USA
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1. It's cheaper to make a vacuum on earth around a computer than it is to send a computer into space.
2. That would also presumably work on earth, unless it somehow relied on low-gravity, and would also be cheaper to benefit from on earth.
That’s not what 1 is about.
The problem for 1 is how do you dissipate heat without being in contact with a lower temperature mass.
Creating a vacuum on earth would solve nothing as the heath would still have to escape the vacuum.
> new technology improves vacuum heat radiation efficiency
Isn't this fixed by blackbody radiation equations?
That equation have surface area ? What if new material found to be extremely large surface area to weight ratio to dissipate lots of heat ?