Comment by typ
1 day ago
Assuming that we place an iron ball (ideal sphere-shaped and thermal conductivity) on the SSO (solar synchronous orbit), how hot can the object be?
Given the solar constant 1361 W/m^2, you can calculate the temperature range based on the emissivity and absorptivity. With the right shape and “color”, the equilibrium temperature can be cooler than most people thought.
I suppose that a space data center powered 100% by solar is no different than this iron ball in principle.
The ideal shape would be a shaded, flat panel perpendicular to the sun right?
That should be better than a sphere. Though I imagine there could be some fancier 3D geometry designs.
Even for a simple sphere, if we give it different surface roughnesses on the sun-facing side and the "night" side, it can have dramatically different emissivity.
About 120 degC.