I am unaware if Hanson has written about this. Panspermia could happen by the first replicators happening in space perhaps on comets and then spreading to planets. As Hanson has pointed out, if life is extremely rare it is strange that life would originate on earth when there are almost certainly super-earths on which you would think life would be much more likely to develop. A solution to this paradox is that life did develop on such an Eden and then spread to earth billions of years ago from a star system that is now far away. Our sun might have been very close to the other star system when life spread, or indeed in the same system at the time.
I am unaware if Hanson has written about this. Panspermia could happen by the first replicators happening in space perhaps on comets and then spreading to planets. As Hanson has pointed out, if life is extremely rare it is strange that life would originate on earth when there are almost certainly super-earths on which you would think life would be much more likely to develop. A solution to this paradox is that life did develop on such an Eden and then spread to earth billions of years ago from a star system that is now far away. Our sun might have been very close to the other star system when life spread, or indeed in the same system at the time.