Proteus gets plastered

I've been doing a project for Greely's planetary geology class on micrometeorite bombardment of outer planet satellites. This is a challenge because the micrometeorite dust particles are gravitational focused (same principle as a spacecraft doing a gravity assist) and speed up quite a bit, depositing kinetic energy, and crystallizing the surface amorphous ice. The results that I'm getting indicate that the closer in the sat is, the more it gets plastered by these dust particles. Proteus is very close in, so it get alot of impacts. Curiously, the spectra of Proteus shows very little water ice. This may mean the plastering has removed the surface ice, plasticizing the surface. Fun stuff!