pluto simulation

Well today i was a bit bored and tried to simulate a visual-future i see on the planet Pluto that’s regular in the news now. I noted the white area, how it seams to have sharp edge and some kind of vague raw ending on the other side. Like if a giant snowball had hit the dwarf-planet, exploded on it and some smeared out over the surface.

So i create a large icosphere put collision on it, disabled gravity in the scene, instead used a point force for the planet.
Then created another sphere.
This sphere was just a particle system 10000 particles, volume based (not surface), to start at frame 1 and to end at frame 2 with a lifetime of 250, and used the xyz as velocity vector. Resulting in volume of that sphere filled with particles.
Later i tuned it a bit more and made it fluid particles, with high viscosity.
Then i played a lot to get the right values for particle friction and planet collision.
Well in the end i got something, that i liked and resulted into similar visual features.

But there was a strange thing, that didn’t seam to be correct.
Because i aimed at the north of my Pluto with my particle ball, after the impact, then the top of my snowball grazed, and some bounced off. Together that part of the ball, followed a trajectory circulating my Pluto.

Well i was thinking that must be wrong, an unwanted artifact in my render.
I tried to adjust it a bit more, and eventually stopped it and closed blender, i gave up on it.

Then…
This evening i was watching TV; discovery channel, it was about the Pluto mission, and long story short, it seams pluto has irregular moons, and they think they must be formed as a result of some collision debris left over.
i should have saved my work …