Similarly, if it is dusty or there are a lot of other larger particles in the air, this will filter out larger wavelengths, resulting in a red sky and red sun.

They can be any protected space, provided that the walls and roof are thick and dense enough to absorb the radiation given off by fallout particles.

Light pollution is made worse with air pollution, as the small particles that float in the air serve to scatter and reflect the light, compounding the problem.

The polymer spheres and carbon particles arrange themselves spontaneously into the correct crystal structure when encouraged by a little heat, so manufacturing opalescent film should be easy.

The movie almost gets this one right - Earth' s magnetosphere does protect us from blasts of subatomic particles from the sun.