3 ms·
Rough estimates give me fairly low surface temperatures for Dyson spheres having the average diameter of Pluto's orbit (~ 5.85e9 km) or the Kuiper Belt (~6e10 k
by ridgeguy 12y ago
Rough estimates give me fairly low surface temperatures for Dyson spheres having the average diameter of Pluto's orbit (~ 5.85e9 km) or the Kuiper Belt (~6e10 km).
The Sun radiates ~ 10e26 Watts, or ~ 1.21e8 W/m^2 at a temperature of ~ 5800°K. Given that radiated power is proportional to (area)*T^4 and making simplifying assumptions about emissivity, etc., I get that a Dyson sphere around our Sun at Pluto's orbit would have a temperature of about 76°K, and a Dyson with a diameter of the Kuiper Belt would have a surface temperature of about 24°K.
So if the radiator is large enough (i.e., if your civilization is sufficiently advanced), you can dump stellar levels of power to space at quite modest temperatures.
- danieltillett 12y agoNice work. You don’t need a solid Dyson sphere of that size, just IR mirrors or Fresnel lenses (these could down to a molecule in thickness) to direct the IR energy into collectors. I would imagine that it would be more efficient to have multiple shells of Dyson spheres with each capturing the waste heat of its immediate inner shell. I read through the original paper and the lowest object temperature they were able to detect was around 150˚K. Any Dyson sphere dumping that amount of energy would be pretty inefficient.