this post was submitted on 01 Jul 2026
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Two main problems with data centers. Power and cooling. In space the power is doable. The cooling is a major pain in the ass and always has been. There are only three ways to get rid of heat. Conduction, convection, and radiation. The first two don’t work because of the vacuum thing. The third is horribly inefficient. Just look at the ISS and the giant fins that only dumps about 70 kW of waste heat through radiator “wings” that weigh several tons. A single rack in a high density compute rack can generate 100kW by itself.
So yeah given the expensive and how inefficient it is, it’s a terrible idea.
Edit: I’m a system architect so dealing with data center heat is something I’m familiar with.
Basically they'd need about as much in radiator fin surface area as they would have in solar panel area. The ISS has 8 solar array wings, 35m x 12m, that can produce about 30 kW each, or 240 kW total, in sunlight (which is only half the time). The ISS has a complex cooling system, but relies on 4 radiators about 3.1 m x 13.6 m to reject up to 14 kW of heat each (56 kW total) for cooling the solar arrays themselves. The main cooling system uses 6 radiators, each 23.3 m x 3.4 m, to reject 70 kW of heat (from this report it sounds like each radiator may be capable of rejecting more than 1/6 of the heat but that the system as a whole needs to be kept under 70 kW of heat rejection).
So that seems like about 650 square meters of radiators can provide about 120 kW of heat rejection.
Today, a 72-GPU Blackwell server is 130 kW in a single server rack. The next generation rolling out now has 72 Rubin GPUs in a 230 kW server, in a single rack. And that's not even a "data center." That's just a single (albeit very powerful) server. How many can you string together, with networking equipment beaming data connections back down to the ground, before the ratio of solar panels and radiators to the actual ship size becomes unworkable?
That said, it's technically possible, especially if you can radiate the heat at higher temperatures than the ISS does, as the Stefan-Boltzmann law shows that the hotter the radiator, the more heat it can reject. Just completely infeasible from an engineering and economical standpoint, for any data center that hopes to be relevant in an age of 100+ MW data centers.
All they're sending up is 1 server rack. 125kw avg, 150kw peak.
Radiator needs to be ~twice as big as ISS, but we probably have improved their efficiency in recent years so maybe not twice?