re: Of course...
There are asteriods of mostly nickel-iron, I wonder if there are a small number asteriods which are rich in fissionable ore? I think it's more likely the there are rocks which have thorium in high concentration- and that could be put in a breeder reactor and made reactor fuel- and then made in to bomb material. But wonder if there rocks out there which are highly radioactive [and would this be easy to detect]?