> Sure it varies a bit
No, not just a bit. It varies by hundreds of degrees depending on the materials α/ε ratio.
Your mental model is off: materials that good absorbers but poor emitters will get very hot, and the flip-side stay cool, and are used to make the cooling elements in the ISS . The temperature of ball of black nickel at 1 AU will settle at balmy 239C - not -18C. Polished Aluminum -> roughly 145C.
Re:SpaceX – Starfall
by robotresearcher on Thursday November 05, 2026 @11:23PM
(#50388163)
I’ve made a note not to make my space data center a black nickel sphere, and instead to make it like we generally make satellites.
My nickel guy is gonna be so disappointed.
Why keep pushing back on this point? The total available energy from the sun in LEO averages about 1.36KW/m^2, and more than this can be radiated away by current deployed technology.
Solar powered space data centers probably make no economic sense. But not because we can’t cool them. We wouldn’t be able to run them very hot because there isn’t enough power there to do so.