OT: Ceres more interesting than previously thought

[douglas]

Kamog said:
I thought depleted uranium emits its own radiation, doesn't it? So although it may stop outside radiation, it probably won't be very healthy to live inside walls made of the material.

Uranium has an extremely long half-life under normal conditions (4.47 billion years), so it really doesn't emit much radiation. What little it does emit can probably be blocked by a very thin layer of something else. The primary health concern with uranium is about its chemical properties.

Kamog said:
Also, I don't understand why radiation that passes through the human body won't do any damage. Wouldn't it still do damage as it passes through, just like a bullet that passes through the body?

A bullet passes through the body because it's massive and fast enough to push the body out of its way. An atomic or smaller scale particle would pass through the body because it's so small or interacts so little with most matter that the body is effectively empty space as far as that particle is concerned. For example, there are trillions upon trillions upon trillions of neutrinos passing through your body every second, but they are so miniscule, light, and electromagnetically neutral that they don't actually "hit" anything on their way through. If you sent a stream of neutrinos straight through the Earth, going directly through the core, the vast majority of them would go all the way through and come out the other side without interacting with any of the matter in the way in the process.