Hello @leeart!
Satan and his followers were banished from heaven. Before coming to Earth, they went planet to planet but Earth was the place they were "accepted" or sin was allowed.
The fact that they traveled from planet to planet indicates that there was a means of transport and that they could possibly survive other environments. Interesting.
If there are aliens, then that would be an affirmation of that belief. However, we still don't know anything. Everything is just an assumption.
However, each theory brings us closer to the truth.
Thanks for coming by 