Yep. Radiation is deadly to computers, and without the atmosphere to protect you there is a LOT of radiation in space.

Basically the way you would make a stealth spaceship would be by focusing as much as possible on energy efficiency. At every juncture you would try to use as little power as possible, and use every bit of it as efficiently as possible, so that you’re not remitting waste. That waste, in the form of heat, radio waves, etc, is what gets you spotted.

You could also run heatsinks temporarily for enhanced stealth as you suggest, then open up radiators to cool them - or eject them - once it’s safe to do so.

(For the Elite: Dangerous players, yes, that game got it right.)

The entire ISS has 14GW of cooling (and a lot of that just goes towards keeping the sun from cooking it). A single server rack can produce around 72GW of heat.

The ISS cost about $100 billion.

Basically, if you took the entire budget of Sam Altman’s “Stargate” project (money that, to be clear, he does not have and will not get) and put it into space data centres you might, optimistically, put one rack in space.

Most data centres have dozens to hundreds.

You’re absolutely correct, but “quite big” might be the single biggest understatement I’ve seen in my life.

You need to think about how an infrared laser works. You’re taking electricity, converting it into light and then focusing the light.

So you’d need to take the heat from your GPUs, inefficiently convert it into electricity (a lot of it would remain as heat), then inefficiently convert electricity into light (much of the electricity would turn back into heat in this process) and then focus the light away from the space data centre.

Now, we already have a process for moving heat away from things as infrared light, without going through all those steps (which would just reduce the efficiency of the process). It’s called a radiator, and it’s how we cool things in space. That’s literally where the name comes from; they radiate heat away as infrared light. That’s why hot things glow in thermal cameras.

It is incredibly inefficient. Radiation (ie, infrared light) is, by far, the worst way of cooling things. But in space its the only option you have, because there’s no convection or conduction across vacuum.

A top end GPU puts out about 1,000 watts of waste heat. The entire International Space Station has enough cooling for 14 of those, if it was doing nothing else whatsoever. An average server rack contains 72. The ISS cost $100 billion dollars. So at a minimum you’re looking at around $500 billion to put one single server rack in space. And that’s before accounting for the heat from the sun, which we can’t avoid because we need solar power to run this thing. So probably closer to a trillion. In other words, twice the already ludicrous price tag of Sam Altman’s “Stargate” project. For a single server rack.

For anyone who doesn’t know, this is because space is an absolutely terrible place to put computers. Getting power is actually the easiest problem to solve, and is still really hard, because building any kind of infrastructure in space is hard. Then you’ve got all that radiation you have to shield against because you’re no longer protected by the Earth’s atmosphere, and worst of all you’ve got the cooling problem because Jesus fucking Christ, space is not cold!

This is why I get annoyed every time a scifi movie shows people freezing to death in space. Because it leads to this level of mass delusion and then suddenly it matters and everyone just unquestioningly believes the lie that space is cold. Space is a vacuum. A vacuum is what your Contigo travel mug uses to keep your coffee scalding hot after four hours. If vacuums are that good at keeping something hot when it naturally wants to get colder, think about what they’ll do to something that is actively generating heat. All of your components are going to cook.

There are proposals to put data centres at the bottom of the ocean that are substantially more credible than this idiocy.