Generators, so far as I know, have ALWAYS contained magnets, either permanent ones or electromagnets. Is this some sort of generator you are talking about?
The thing about Pluto was that more was learned, not just about Pluto, but about other smaller orbiting planetoids, and it turns out that at least one of them was bigger than Pluto. Basically they simply redefined a planet as being something larger than Pluto and other planetoids. Pluto has not changed at all, we have just learned more about it.