I guess I'm still learning all the strange practices on this ,essage board.
O well, despite the thread being a few years old, I'll just say that the solar system did not come about by an accidental collision, whatever accident means in this context.
Long story short, there are things called nebulae and in a lot of these there is star formation going on. All the gasses and dust floating around gets pretty close and some of it coalesces into "piles" so to speak. Collections of things tend toward the shapes of disks in space. The huge disk of matter continues to fall toward the middle, so much so that the middle starts to glow with incandescence. Then one day it just can't take it anymore and a fusion reaction kicks off, the birth of the star. There is still a lot of stuff floating around in chunks. The chunks keep banging into each other and sticking. Soon larger and larger chunks form, especially in regions where orbits tend to be pretty stable. These large chunks continue to sweep out regions in the "minefield" and continue to grow. They keep getting pelted with material until they are the size of the planets we see today.
Sp planets are the result of many many many collisions, but the solar system as a whole is not the result of one collision.
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