Comment by svantana
7 hours ago
How hot do you think black objects in space get? Something like 10°C. Look up thermal equilibrium of an ideal black body.
7 hours ago
How hot do you think black objects in space get? Something like 10°C. Look up thermal equilibrium of an ideal black body.
In the vicinity of the Earth, they get to about the temperature of the Earth. That’s not a coincidence. Hotter if they are actively generating heat.
So you can have datacenters in space, you are just not allowed to use them
Not using them would also solve all issues with cosmic radiation.
Nobody (sane) is talking about putting nuclear reactors on Satellites in close Earth orbit so we don't have to worry about them generating heat. They've got solar panels that move some of the solar energy they absorb to a central location which presents problems in moving the waste heat back out so that spot doesn't get too hot. But that doesn't change the overall equilibrium temperature.
Running a data center generates heat.
But are they doing work internally that generates heat? Genuine question.
They are. But only as much heat as they get from the solar radiation that's hitting them anyway. Exactly that amount.
Except you aren't leaving that heat in place.
You're concentrating it into a very small area of compute.
If you don't spread that heat back out, it's going to find a much higher thermal equilibrium than the solar panels themselves would find just absorbing the sunlight and radiating the energy back into space.
It's like you've pointed a magnifying glass at your compute, except with electricity, which means you can reach temperatures higher than you can with a magnifying glass.
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If you gather 1kW of power from the sun then you have to reject 1kW of heat once you are done with whatever computation you are doing. There’s a bit more heat absorbed from the environment since some sunlight strikes parts of your satellite that are not solar panels, but it’s not too bad. Starlink satellites, just to pick a relevant example, do not need a radiator at all because they stay mostly edge–on to the sun and they can radiate all the heat through their own surface area. The ISS needs big radiators because they want it to be comfortable for humans, but electronics can run significantly hotter than that.