Wow, what did I start? Again I will state that just because we can’t imagine how to do it does not mean it can’t be done. We do not know everything and it may well be that the current solar system could have been produced from a range of origins rather than a small specific set. I don’t think we can assume that we are the desired outcome, but a second generation planet supporting life may have been. The end result may not have been X but Q through Z. There is so much we don’t know take planet number nine, we know about where it must be, and how big it must be but that’s about it. We thought we had Pluto figured out but we were wrong about almost everything. What we think we know is pretty amazing until you realize we are missing about 90% of the universe. It’s like planet 9, we know it’s there and about how much of it there should be, but what it is we still don’t know.
Current cosmographers are able to make pretty good models of how the solar system formed with the computers we have now. If I got it right we have new systems about to come on line that will make current super computers look like toys.
I would be very careful about using words like impossible. Liquid water on Pluto was impossible not long ago. I still think you are overthinking it. Our planetary system is anomalous. We have found none like it. Why? They should be there. I think that one possible answer might be that our solar system is an artifact. Big problems for us yep, but maybe there are others for whom it might not be. I also think you may be looking at this as a problem that must always come out exactly right,but maybe the same thing was tried in a hundred and fifty systems, and we were the lucky ones. Maybe Mars was the desired result and we are just the leftovers from a failed experiment.
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