[dhs12345]

Learned the other day that water makes a good insulator from neutron radiation. I presume that the same will happen with ice?

Hey, if you are going to freezie pop the astronauts why not flood the tank with water and free the whole thing?

[Telepathic Intruder]

There is this unfortunate thing that happens with water when it freezes—it expands. Freeze a human body and every cell explodes like they’re glass bottles.

[Tijeras_Slim]

Light atoms are what does the trick, such as hydrogen. Beryllium works well if you need a more solid material. Polyethelene (C2H4) is also good.

[Wonder Warthog]

"Learned the other day that water makes a good insulator from neutron radiation. I presume that the same will happen with ice?"

It is actually the hydrogen (protons) in the water that does the shielding. Paraffin wax, polyethylene, and similar compounds are also good neutron shielding materials.