For some perspective, the entire heat rejection system on the ISS at peak can do a little less than one rack of dense AI compute power.

All of that plumbing, all of that area, all that stuff to put in orbit just to cool one rack of compute equipment.

How much stuff do we need to put up there for each rack? The External Active Thermal Control System on the ISS is ~20,000lbs, about 10 tons. How many racks are in a single datacenter? The Colossus is allegedly ~1,500 compute racks, ignoring other equipment. So that's like 15,000 tons for just the cooling equipment if its like the ISS. At SpaceX's current public launch costs (which makes a profit for them, so not base costs) to launch that much stuff is somewhere around $40B. Just the launch cost for the cooling equipment alone for just one datacenter building worth of pure compute capacity, that isn't even that big compared to what companies are talking about building.

All of that is very rough back of the napkin math. I don't expect that to be the actual numbers at all, but I'd imagine somewhere in that neighborhood unless they've got something really radical up their sleeve.

They better have a much better way to cool these things than what the ISS is doing.

Current SpaceX design is 75 kW of computer per ton, including solar panels, radiators, everything: https://www.spacex.com/spacexai/starmind

That's ~13 tons per megawatt, or 1,330 tons for 100 MWs. That's 13 launches of Starship (at $10 million per launch, or $130 million). Of course, that's probably 600 individual satellites, at maybe $5 million per, so we're at ~$3 billion to deploy 100 MW to space.

You can sell 100 MW of compute for $3-4 billion per year, so SpaceX would make their money back in 1 year.