(the modeled numbers for Callisto are for being behind a bare aluminum hull - but that's roughly at parity with the Chang'e measurements, I think?)

The source for this assertion was a .txt file lesson plan from 2000, so I went a-hunting for better data... and found it! "Radiation analysis for manned missions to the Jupiter system" (G.D. Angelis et al, 2003) models a 1.8 mSv/day dose on Callisto - a shade *higher* than the Moon (1.4 mSv/d).

Metallic snow (or maybe frost, depending on your definition of "snow") is radar-bright material at the tops of Venus’ highest mountains, such as Maxwell Montes (11 km high), possibly made of condensed lead sulfide and bismuth sulfide that sublimate at warmer altitudes and condense on mountaintops ❄️