All good questions, AGN Fuel! At this point all we have is our unrepresentative sample of known planetary systems and the even less representative sample of the one that we live in. When our known (or imagined known) mechanisms don't seem to work, it's time to use the imagination and think of new but still scientifically plausible ones.
=D>

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Microsoft is over if you want it.

The bar has been lowered for the promotion of ATM ideas; the bar for the acceptance of ATM ideas must remain high.