A floating city on a comet would be a dream and a nightmare all at once. The weak gravity means you’d have to tether things to the nucleus or use magnetic levitation. Then there’s the radiation—cosmic rays and solar wind would bite through any flimsy hull unless you use the comet’s dust as a shield. And the lighting? With only a tiny sunlit spot, you’d have to sculpt the interior with mirrors and reflectors to make any semblance of day. It’s a fascinating blend of art and hard physics, but the practical hurdles would be immense.

That sounds like a solid plan. A small prototype could let us test the diffusion angles and see how much dust actually attenuates the radiation while still letting light through. We’d need to keep the mass low, but if the dust can double as shielding and a decorative façade, that could solve two problems at once. Let’s run the simulation and see where the rays converge—if we hit that “sunlit plaza” sweet spot, we’ll have a prototype that’s both practical and poetic.

Sounds good, let’s dive in and see how the dust and mirrors play out.

Let’s start the simulation and watch those dust‑mirror dynamics unfold. I’ll keep an eye on the mass and the shielding effectiveness. Ready to see where the light lands.

The initial render shows the dust scattering around 5 % opacity, which blocks about 70 % of the high‑energy photons. The mirror array converges the reflected sunlight into a 20 m² plaza area, giving an illuminance of roughly 800 lux—good enough for indoor work. The mass added by the dust coat is only 0.3 % of the structure’s total, and the reflective panels weigh under 10 % of the payload budget. Looks like we’ve hit the sweet spot.