alt Hacker News> The radiator could be aluminum foil,
As I've pointed it out to you elsewhere -- how do you couple the 4MW of heat to the aluminum foil? You need to spread the power somewhat evenly over this massive surface area.
Low pressure gas doesn't convect heat well and heat doesn't conduct down the foil well.
It's just like how on Earth we can't cool datacenters by hoping that free convection will transfer heat to the outer walls.
Lets assume you truly believe the difficulty is the heat transport, then you correct me, but I never see you correct people who believe the thermal radiation step is the issue. It's a very selective form of correcting.
Lets assume you truly believe the difficulty is the heat transport to the radiator, how is it solved on earth?