Why are planetary orbits quasi-circular?

You may have seen this funny little applet. It is practically a poster child for Scalable Vector Graphics (SVG). But the conclusions that the page tries to get you to are interesting. Essentially: the moon cannot have gotten into orbit if you follow newtonian mechanics.

That got me thinking. There is a good question in this little applet after all: why are planetary orbits so circular? Consider the solar system data (or, in a more picturesque form, at solar system animations), it is quite apparent that the eccentricities of the various planets are pretty small. There is nothing necessary to this fact. As a matter of fact, if you look at the comets in the animation above, their orbits are very obviously not circular. So why would the planets be different?

You see, this is another reason why I believe that Laurent Nottale is a genius: in my humble opinion, his theory provides a very neat explanation to this fact. The reason is that, under relatively reasonable conditions, the position of planets is no longer arbitrary. It obeys a probability structure very similar to Schrödinger’s equation. If a central potential dominates, the peaks of this probability distribution are on spheres centered around the main massive body. This means that the accumulation of large amounts of matter necessary to form a planet is highly likely to happen on a quasi-circle. I would find it quite difficult to explain this using only Newtonian mechanics or general relativity. Actually, Google did not help me.

Please comment if you know better.

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