Sure. Now do cooling. That this isn't in the "key challenges" section makes this pretty non-serious.
A surprising amount of the ISS is dedicated to this, and they aren't running a GPU farm. https://en.wikipedia.org/wiki/External_Active_Thermal_Contro...
More seriously though, the paper itself touches on cooling and radiators. Not much, but that's reasonable - cooling isn't rocket science :), it's a solved problem. Talking about it here makes as much sense as taking about basic attitude control. Cooling the satellite and pointing it in the right direction are solved problems. They're important to detail in full system design, but not interesting enough for a paper that's about "data centers, but in space!".
It's solved on Earth because we have relatively easy (and relatively scalable) ways of getting rid of it - ventilation and water.
Sure, in the same sense that I could build a bridge from Australia to Los Angeles with "no new tech". All I have to do is find enough dirt!
We're past the point of every satellite being a custom R&D job resulting in an entirely bespoke design. We're even moving past the point where you need to haggle about every gram; launch costs have dropped a lot, giving more options to trade mass against other parameters, like more effective heat rejection :).
But I think the first and most important point for this entire discussion thread is: there is a paper - an actual PDF - linked in the article, in a sidebar to the right, which seemingly nobody read. It would be useful to do that.
Now ask them to do the Australia / Los Angeles one.
"lol no"
The where and the scale matter.
Scale: Lots of small satellites.
I.e. done to death and boring. Number of spacecraft does not affect the heat management of individual spacecraft.
Much like number of bridges you build around the world does not directly affect the amount of traffic on any individual one.
Challenging!
> Scale: Lots of small satellites.
So we're getting cheaper by ditching economies of scale?
There's a reason datacenters are ever-larger giant warehouses.
> Much like number of bridges you build around the world does not directly affect the amount of traffic on any individual one.
But there are places you don't build bridges. Because it's impractical.
Thus, if launch costs to LEO reach $200/kg, then the cost of launch amortized over spacecraft lifetime could be roughly comparable to data center energy costs, on a per-kW basis.
If the [SpaceX] learning rate is sustained—which would require∼180 Starship launches/year—launch prices could fall to <$200/kg by∼2035.
Realizing these projected launch costs is of course dependent on SpaceX and other vendors achieving high rates of reuse with large, cost-effective launch vehicles such as Starship.
The economy of scale here is count, not size. This is also why even data centres are made from many small identical parts, such as server racks, which are themselves made from many smaller identical parts.
What makes LEO cheaper than it used to be, has been reuse. We'll see if "bigger" actually plays out as Starship continues.
> But there are places you don't build bridges. Because it's impractical.
What is and isn't practical changes as technology develops.
Look, I am skeptical of space based beamed power and space based compute, but saying any given proposal must still be bad in 2035 because it would be bad with today's tech is like betting against the growth of EVs or PV in 2015, or against the internet in 1990.
(The reverse mistake is to say that it must succeed, like anyone in 1970 who was expecting a manned Mars mission by 1980).